Sea Level Rise and Storm Surge Projections for the 

National Park Service

Natural Resource Report Series NPS/NRSS/NRR—2018/1648

National Park Service 

U.S. Department of the Interior 

Natural Resource Stewardship and Science 
ON THIS PAGE

Driftwood washed up on the shoreline of Redwood National Park, California. 

Photograph courtesy of Maria Caffrey, University of Colorado.

ON THE COVER

Fort Point National Historic Site and the Golden Gate Bridge, California.

Photograph courtesy of Maria Caffrey, University of Colorado.
Sea Level Rise and Storm Surge Projections for the 

National Park Service

Natural Resource Report Series NPS/NRSS/NRR—2018/1648

Maria A. Caffrey1, Rebecca L. Beavers2, Cat Hawkins Hoffman 3

1 University of Colorado

Geological Sciences Building

UCB 399

Boulder, CO 80309

2National Park Service

Geologic Resources Division

7333 W. Jefferson Avenue

Lakewood, CO 80235

3National Park Service

Climate Change Response Program

1201 Oakridge Drive, #150

Fort Collins, CO 80525

May 2018 

U.S. Department of the Interior

National Park Service

Natural Resource Stewardship and Science 

Fort Collins, Colorado
ii

The National Park Service, Natural Resource Stewardship and Science office in Fort Collins, 

Colorado, publishes a range of reports that address natural resource topics. These reports are of 

interest and applicability to a broad audience in the National Park Service and others in natural 

resource management, including scientists, conservation and environmental constituencies, and the 

public.

The Natural Resource Report Series is used to disseminate comprehensive information and analysis 

about natural resources and related topics concerning lands managed by the National Park Service. 

The series supports the advancement of science, informed decision-making, and the achievement of 

the National Park Service mission. The series also provides a forum for presenting more lengthy 

results that may not be accepted by publications with page limitations.

All manuscripts in the series receive the appropriate level of peer review to ensure that the 

information is scientifically credible, technically accurate, appropriately written for the intended 

audience, and designed and published in a professional manner. 

This report received formal peer review by subject-matter experts who were not directly involved in 

the collection, analysis, or reporting of the data, and whose background and expertise put them on par 

technically and scientifically with the authors of the information.

Views, statements, findings, conclusions, recommendations, and data in this report do not necessarily 

reflect views and policies of the National Park Service, U.S. Department of the Interior. Mention of 

trade names or commercial products does not constitute endorsement or recommendation for use by 

the U.S. Government.

This report is available in digital format from the Climate Change Response Program website and the 

Natural Resource Publications Management website. If you have difficulty accessing information in 

this publication, particularly if using assistive technology, please email irma@nps.gov.

Please cite this publication as:

Caffrey, M. A., R. L. Beavers, and C. H. Hoffman. 2018. Sea level rise and storm surge projections 

for the National Park Service. Natural Resource Report NPS/NRSS/NRR—2018/1648. National Park 

Service, Fort Collins, Colorado.

NPS 909/145268, May 2018
iii

Contents 

Page

Figures...................................................................................................................................................iv

Tables.....................................................................................................................................................v

Photographs...........................................................................................................................................vi

Appendices............................................................................................................................................vi

Executive Summary ............................................................................................................................viii

Acknowledgments..................................................................................................................................x

List of Terms..........................................................................................................................................x

Introduction............................................................................................................................................1

Format of This Report ....................................................................................................................2

Frequently Used Terms .............................................................................................................2

Methods..................................................................................................................................................5

Sea Level Rise Data........................................................................................................................5

Storm Surge Data ...........................................................................................................................8

Limitations....................................................................................................................................11

Land Level Change.......................................................................................................................12

Where to Access the Data.............................................................................................................13

Results..................................................................................................................................................14

Northeast Region..........................................................................................................................17

Southeast Region..........................................................................................................................18

National Capital............................................................................................................................21

Intermountain Region...................................................................................................................22

Pacific West Region .....................................................................................................................25

Alaska Region ..............................................................................................................................25

Discussion............................................................................................................................................27

Conclusions..........................................................................................................................................30

Literature Cited ....................................................................................................................................31
iv

Figures 

Page

Figure 1. Sea level trends for the United States based on Zervas (2009), for all available 

data through 2015 ..................................................................................................................................4

Figure 2. An example of how areas of inundation appear in ArcGIS...................................................8

Figure 3. An example of the extent of an operational basin shown in NOAA’s SLOSH 

display program (http://www.nhc.noaa.gov/surge/slosh.php) .............................................................10

Figure 4. Projected future sea level by NPS region for 2100 under RCP8.5 (the “business 

as usual” climate change scenario) ......................................................................................................14

Figure 5. Projected future sea level rise by NPS region for 2030 under RCP8.5 (the 

“business as usual” climate change scenario)......................................................................................15

Figure 6. Projected future sea level rise by NPS region for 2050 under RCP8.5 (the 

“business as usual” climate change scenario)......................................................................................16

Figure 7. Projected future sea level rise by 2100 for the NPS Northeast Region under all 

of the representative concentration pathways......................................................................................17

Figure 8. Estimated storm surge created by Saffir-Simpson category 3 hurricane 

occurring at high tide near Boston Harbor Islands National Recreation Area.....................................18

Figure 9. SLOSH MOM storm surge maps for a Saffir-Simpson category 1 (left) versus 

category 2 hurricane striking Everglades National Park at mean tide (right)......................................20

Figure 10. A SLOSH MOM map showing storm surge height and extent created by a 

Saffir-Simspon category 2 hurricane striking the Washington D.C. region at high tide .....................21

Figure 11. Projected future sea level rise by 2100 for the NPS Intermountain Region 

under all of the representative concentration pathways.......................................................................23

Figure 12. A SLOSH MOM map showing storm surge height and extent created by a 

Saffir-Simspon category 4 hurricane striking the southwestern Texas region at mean tide................24

Figure 13. Radiative forcing (see list of terms) for each of the Representative 

Concentration Pathways (RCPs)..........................................................................................................27
v

Tables 

Page

Table 1. Observed global mean sea level budget (mm/y) for multiple time periods (IPCC 

2013). .....................................................................................................................................................6

Table 2. Median values for projections of global mean sea level rise and contributions of 

individual sources, for 2100, relative to 1986-2005, in meters (IPCC 2013). .......................................7

Table 3. Saffir-Simpson hurricane categories. ....................................................................................10

Table C1. The nearest long-term tide gauge to each of the 118 national park service units 

used in this report...................................................................................................................................1

Table C2a. Sea level rise numbers by NPS unit for the Northeast Region.........................................12

Table C2b. Sea level rise numbers by NPS unit for the Southeast Region.........................................17

Table C2c. Sea level rise numbers by NPS unit for the National Capital Region ..............................22

Table C2d. Sea level rise numbers by NPS unit for the Intermountain Region .................................26

Table C2e. Sea level rise numbers by NPS unit for the Pacific West Region ....................................27

Table C2f. Sea level rise numbers by NPS unit for the Alaska Region..............................................31

Table C3. IBTrACS data (Knapp et al. 2010) were used to identify the highest recorded 

storm track to have passed within 10 miles of each of the park units..................................................33
vi

Photographs

Page

Photo 1. Looking towards the Gulf of Mexico from Fort Jefferson, Dry Tortugas 

National Park .......................................................................................................................................vii

Photo 2. Basement flooding in the visitor center at Rosie the Riveter WWII Home Front 

National Historical Park........................................................................................................................ix

Photo 3. A National Park Service ranger surveys damage from the aftermath of 

Hurricane Sandy at Statue of Liberty National Monument, NY............................................................3

Appendices

Page

Appendix A........................................................................................................................................A-1

Appendix B........................................................................................................................................B-1

Appendix C........................................................................................................................................B-1
vii

Photo 1. Looking towards the Gulf of Mexico from Fort Jefferson, Dry Tortugas National Park. Photo 

credit: Used with permission from Rachel Sullivan Photography.
viii

Executive Summary

Over one quarter of the units of the National Park System occur along ocean coastlines. Ongoing 

changes in relative sea levels and the potential for increasing storm surges due to anthropogenic 

climate change and other factors present challenges to national park managers. This report 

summarizes work done by the University of Colorado in partnership with the National Park Service 

(NPS) to provide sea level rise and storm surge projections to coastal area national parks using 

information from the United Nations Intergovernmental Panel on Climate Change (IPCC) and storm 

surge scenarios from National Oceanic and Atmospheric Administration (NOAA) models. This 

research is the first to analyze IPCC and NOAA projections of sea level and storm surge under 

climate change for U.S. national parks. Results illustrate potential future inundation and storm surge 

under four greenhouse gas emissions scenarios. In addition to including multiple scenarios, the 

analysis considers multiple time horizons (2030, 2050 and 2100). This analysis provides sea level 

rise projections for 118 park units and storm surge projections for 79 of those parks.

Within the National Park Service, the National Capital Region is projected to experience the highest 

average rate of sea level change by 2100. The coastline adjacent to the Outer Banks Group of parks

in the Southeast Region is projected to experience the highest sea level rise by 2100. The Southeast 

Region is projected to experience the highest storm surges based on historical data and NOAA storm 

surge models.

These results are intended to inform park planning and adaptation strategies for resources managed 

by the National Park Service. Sea level change and storm surge pose considerable risks to 

infrastructure, archeological sites, lighthouses, forts, and other historic structures in coastal units of 

the national park system. Understanding projections for continued change can better guide protection 

of such resources for the benefit of long-term visitor enjoyment and safety. 
ix

Photo 2. Basement flooding in the visitor center at Rosie the Riveter WWII Home Front National 

Historical Park. This photograph was taken on December 5, 2012 —12 years after the establishment of 

the park. Photo credit: Maria Caffrey.
x

Acknowledgments 

This project was awarded funds through the NPS Servicewide Comprehensive Call (FY2013–2015)

and augmented by funds from the Natural Resource Stewardship and Science Directorate’s Geologic 

Resources Division and Climate Change Response Program. We would like to thank the members of 

the communication advisory team (Rebecca Beavers, Lynda Bell, Maria Caffrey, Janet Cakir, Will 

Elder, Stanton Enomoto, Ann Gallagher, Matt Holly, Shawn Norton, Larry Perez, and Ryan 

Stubblebine) and science advisory team (Amanda Babson, Rebecca Beavers, Maria Caffrey, Patrick 

Gonzalez, Steve Nerem, and Rob Thieler) for their time and input into this project. 

We would also like to thank Susan Teel and Caroline Rohe at Gulf Islands National Seashore for 

assistance in designing two wayside exhibits. Likewise, we thank Julie Whitbeck, Aleutia Scott, 

Kristy Wallisch, and Stacy Meyers for helping design, review, and install a wayside at Jean Lafitte 

National Historical Park and Preserve. Elizabeth Rogers and Kathy Krause helped design a wayside 

for Fire Island National Seashore. Doug Wilder, Dorothy Friday, and Neal Jander designed the online 

map viewer. We would also like to thank Jason Kenworthy, Rebecca Port, Michael Barthelmes, Bob 

Glahn, Doug Marcy, Chris Zervas, and Claudia Tebaldi for their assistance in editing and reviewing 

this document. Finally, we thank the National Oceanic and Atmospheric Administration and the 

Intergovernmental Panel on Climate Change for providing the respective storm surge and sea level 

rise data cited throughout this document.

List of Terms

The following list of terms are defined here as they will be used in this report. 

Bathtub model: A simplification of the sea as bathtub of water to simulate a change in water level 

relative to the land. This model does not include other factors such changes in erosion or accretion 

that change alter the geometry of the coastline.

Flooding: The temporary occurrence of water on the land.

Inundation: The permanent impoundment of water on what had previously been dry land.

Isostatic rebound: A change in land level caused by a change in loadings on the Earth’s crust. The 

most common cause of isostatic rebound is the loading of continental ice during the Last Glacial 

Maximum in North America. The North American land surface is still returning to equilibrium after 

the melting of this continental ice in an effort to return to equilibrium with its original pre-loading 

state.

National Park Service unit: Property managed by the National Park Service.

Radiative Forcing: Is the change in the incoming solar radiation minus the outgoing infrared 

radiation: the change in heat at the surface of the Earth. Positive radiative forcing means Earth 

receives more incoming energy from sunlight than it radiates to space. This net gain of energy warms 

the earth, resulting in higher global average temperatures. 
xi

Relative sea level: Where the water level can be found compared to some reference point on land. 

This term is most frequently used in discussion of changes in relative sea level. A change in relative 

sea level could be caused by a change in water volume or a change in land level (or some 

combination of these two factors). 

Sea level: The average level of the seawater surface.

Sea level change: This term is frequently used in reference to relative sea level change. This is the 

product of two main factors, 1) an increase in the volume of ocean water, and 2) a change in land 

level. These two factors can be broken down further into other drivers that will be discussed in 

greater detail in other sections. This term is sometimes mistakenly confused with the term sea level

rise.

Sea level rise: An increase in sea level. This is the result of an increase in ocean water volume caused 

principally by melting continental ice and thermal expansion. This term is not to be confused with 

increasing relative sea level, which can also be caused by decreasing land levels.

Storm surge: An abnormal rise of water caused by a storm, over and above the predicted 

astronomical tide. 
1

Introduction

Global sea level is rising. While sea levels have been gradually rising since the last glacial maximum 

approximately 21,000 years ago (Clark et al. 2009, Lambeck et al. 2014), anthropogenic climate 

change has significantly increased the rate of global sea level rise (Grinsted et al. 2010, Church and 

White 2011, Slangen et al. 2016, Fasullo et al. 2016). Recent analyses reveal that the rate of sea level 

rise in the last century was greater than during any preceding century in at least 2,800 years (Kopp et 

al. 2016, Sweet et al. 2017). Human activities continue to release carbon dioxide (CO2) into the 

atmosphere, causing the Earth’s atmosphere to warm (IPCC 2013, Mearns et al. 2013, Melillo et al. 

2014). Further warming of the atmosphere will cause sea levels to continue to rise, which will affect 

how we protect and manage our national parks. The rate of warming depends on numerous factors 

considered by the Intergovernmental Panel on Climate Change (IPCC) under four different 

representative concentration pathways (RCPs; Moss et al. 2010, Meinshausen et al. 2011). Used as 

the basis for this report, the RCPs are climate change scenarios based on potential greenhouse gas 

concentration trajectories introduced in the fifth climate change assessment report of the 

Intergovernmental Panel on Climate Change (IPCC 2013). The IPCC’s process-based approach for 

estimating future sea levels contrasts with other estimates from semi-empirical techniques that 

commonly generate higher numbers.

This report provides estimates of sea level change due to climate change for 118 National Park 

Service units and estimates of storm surge for 79 of those units. As temperature increases, sea levels 

rise due to a number of factors that will be discussed in greater detail.

The Importance of Understanding Contemporary Sea Level Change for Parks

From rocky headlands to gentle beaches, some of the most splendid and beautiful places in the 

United States are national parks on our ocean shorelines. Over one quarter of all national park units 

are coastal parks, home to nesting shorebirds and sea turtles, historical forts and lighthouses, and 

opportunities for recreation and respite. Many are living witness to our national story – true icons 

of our history (Photo 3). But despite their great diversity, importance, and ability to provide 

windows to the past, changes in sea level affect them all.

Today’s managers of these parks face new challenges—challenges unimagined by builders of the 

forts and lighthouses within them, challenges unprecedented for the species that inhabit them, and 

challenges unanticipated by those who secured these places as part of the National Park System. 

Knowledge of sea level projections must now augment managerial skills in park administration, 

resource protection and conservation, interpretation, and community and civic engagement. To 

support managers of coastal park units, this report provides projections for sea level change and 

storm surge under several scenarios. As a reference for staff, it also summarizes scientific 

understanding of the basis for these changes, and sources from which scientists develop sea level 

rise projections.
2

As sea levels incrementally rise, periods of flooding caused by storms and hurricanes exacerbate the 

growing problem of coastal inundation (see list of terms). Peek et al. (2015) estimated that the value 

of infrastructure at risk in 40 National Park Service units could cost billions of dollars if these units 

were exposed to one-meter of sea level rise. 

The passage of Hurricane Sandy in 2012—and more recently Hurricanes Harvey, Irma, and Maria in 

2017—caused extensive and costly damage to infrastructure and resources in numerous coastal 

national park units. While single storms cannot be wholly attributed to anthropogenic climate change, 

sea level rise associated with climate change exacerbates the effects of associated storm surges, 

which may be even further amplified during the highest astronomical tides as occurred during 

Hurricane Sandy (Kemp and Horton 2013). The impacts of extreme storms can bring extreme costs, 

as tallied through loss of visitor access, impacts to gateway communities and local economies, 

investments in recovery, and/or the irrevocable loss of unique resources. For example, repair of 

damage caused in national parks affected by Hurricane Sandy alone exceeded $370,000,000. Under 

future scenarios of increasing anthropogenic greenhouse gas emissions, models project increasing 

storm intensities (Mann and Emanuel 2006, Knutson et al. 2010, Lin et al. 2012, Ting et al. 2015). 

When this change in storm intensity (and therefore, storm surge) is combined with sea level rise, we 

expect to see increased coastal flooding, the permanent loss of land across much of the United States 

coastline, and in some locations, a much shorter return interval of flooding. For example, when 

Hurricane Sandy struck, it was estimated to have a return period between 398 (Lin et al. 2016) and 

1570 (Sweet et al. 2013) years. Factoring in future sea level rise to these estimates reduces the 

potential return interval of a similar storm surge occurring in New York City by 2100 to between 50 

years (Sweet et al. 2013) and 90 years (Lin et al. 2016).

The aim of this report is to: 1) quantify projections of sea level rise in coastal National Park Service 

units over the next century based on the latest IPCC (2013) models, and 2) show how storm surge 

generated by hurricanes and extratropical storms could also affect these parks.

Format of This Report

This report contains five sections (introduction, methods, results, discussion, and conclusion), and 

presents results per park alphabetically by region. The 118 park units studied for this project cover

six administrative regions: the Northeast, Southeast, National Capital, Intermountain, Pacific West, 

and Alaska. The scope of this project focuses on sea levels. The scope of this project did not include 

projected changes in lake levels, although interior waterways and lakes, especially the Great Lakes, 

are vulnerable to the effects of climate change. Further explanation on how to access the data from 

this project is available in the methods sections and accompanying appendices.

Frequently Used Terms

Definitions of the most basic terms used in this report occur on page ix. However, some terms require 

greater explanation for their use. For example, we follow the advice of Flick et al. (2012) in 

differentiating between the terms flooding and inundation. While many choose to use these terms 

interchangeably, we use the term “flooding” to describe the temporary impoundment of water on 

land. This usually results from storm activity and other short-lived events, such as periodic tidal 

action, and will therefore be used here in reference to the effects of a storm surge on land. 
3

“Inundation” refers to the gradual permanent submergence of land that will occur due to sea level

rise.

The terms sea level rise and sea level change are also used differently. Sea level rise refers only to 

rising water levels resulting from an increase in global ocean volumes. In most parts of the United 

States this increase in water volume will lead to increasing relative sea levels. However, in some 

parts of the country relative sea level is decreasing due to isostatic rebound. Figure 1 shows current 

sea level trends based on tide gauge records for United States that span at least 30-years of data.

For example, Southeast Alaska is experiencing a decrease in relative sea level. Alaska’s crust 

continues to rebound following the melting of large volumes of ice that occurred for centuries to 

millennia on land in the form of glaciers and ice fields. Alaska is tectonically complex with extensive

faults that contribute to this crustal motion. Although the volume of ocean water in this region is 

increasing, the rate of sea level rise is less than the rate of isostatic rebound, resulting in a decrease in 

relative sea level. For this reason, we use the term “sea level change” as it includes regions that will 

experience a decrease in relative sea level (at least in the early part of this century) as well as those 

that will see increasing relative sea levels. 

Photo 3. A National Park Service ranger surveys damage from the aftermath of Hurricane Sandy at 

Statue of Liberty National Monument, NY. Photo credit: National Park Service.
4

Figure 1. Sea level trends for the United States based on Zervas (2009), for all available data through 2015. Each dot represents the location of a 

long-term (>30 years) tide gauge station. Green dots represent stations that are experiencing the average global rate of sea level change. Stations 

depicted by yellow to red dots are experiencing greater than the global average (primarily driven by regional subsidence) and blue to purple dots 

are stations experiencing less than the global average (due to isostatic rebound or other tectonically-driven factors). Source: 

https://tidesandcurrents.noaa.gov/sltrends/slrmap.htm
5

Methods

This report summarizes work of a project initiated in 2013, analyzing sea level change in 118

National Park Service units. Consultation with regional managers regarding units they considered to 

be potentially vulnerable to sea level change and/or storm surge resulted in selection of these 118 

coastal park units (Appendix B). Project activities included the following:

1) Prepare sea level projections over multiple time horizons for each park unit.

2) Estimate potential exposure to storm surge using the National Oceanographic and 

Atmospheric Administration (NOAA) Sea, Lake, and Overland Surge from Hurricanes 

(SLOSH) Model and Tebaldi et al. (2012).

3) Create wayside exhibits1 with information about the impacts of climate change in the coastal 

zone for three National Park Service units.

Based on site recommendations from regional personnel, three National Park Service units now have 

completed wayside exhibits in place: Gulf Islands National Seashore, Jean Lafitte National Historical 

Park and Preserve, and Fire Island National Seashore, each with customized designs that reflect the 

messaging and/or themes of each unit. This report provides results from the first two project 

activities: sea level rise projections, and potential exposure to storm surge.

Sea Level Rise Data

Sea level rise is caused by numerous factors. As human activities release CO2 and other greenhouse 

gases into the atmosphere, mean global temperatures increase (IPCC 2013). Rising global 

temperatures cause ice located on land and in the sea to melt. The melting of ice found on land, such 

as Greenland and Antarctica, is a significant driver of sea level rise.

While the melting of sea ice is problematic from an oceanographic and heat budget perspective 

(primarily because it alters water temperatures and salinity and also because it changes the 

reflectance of solar energy from the surface), melting sea ice does not cause sea level rise. It is the 

melting of ice that is currently stored on land that raises global sea levels. Water level does not 

change when sea ice (ice wholly supported by water) melts. The volume of water in the sea remains 

the same whether it is frozen or liquid. The phase shift of water from solid to liquid does not displace 

an additional volume of water.

As ocean waters warm, the density of these waters also changes, causing thermal expansion. Thermal 

expansion was responsible for two-fifths of sea level rise from 1993 to 2010, while melting ice 

accounted for half (IPCC 2013). Table 1 lists the contribution to sea level rise from several key 

sources.

 

1 A wayside is an exhibit designed to be installed outside for visitors to learn about a particular subject 

(https://www.nps.gov/hfc/products/waysides/).
6

Table 1. Observed global mean sea level budget (mm/y) for multiple time periods (IPCC 2013).

Source 19011990 19712010 19932010

Thermal expansion n/a 0.08 1.1

Glaciers except in Greenland and Antarcticaa 0.54 0.62 0.76

Glaciers in Greenland 0.15 0.06 0.10b

Greenland ice sheet n/a n/a 0.33

Antarctic ice sheet n/a n/a 0.27

Land water storage -0.11 0.12 0.38

Total of contributions n/a n/a 2.80

Observed 1.50 2.00 3.20

Residualc 0.50 0.20 0.40

aData until 2009, not 2010.

bThis is not included in the total because these numbers have already been included in the Greenland ice sheet.

cThis is calculated as observed global mean sea level rise  modeled glaciers  observed land water storage.

See table 13.1 in IPCC (2013) for more details.

The IPCC sea level rise projections used in this analysis follow a process-based model approach, 

which estimates sea level based on the underlying physical processes. This contrasts with semiempirical models that combine past sea level observations with other variables or theoretical 

considerations, including, in some cases, expert opinion (surveys or interviews of professionals)

(Rahmstorf 2010, Orlic and Pasaric 2013). Often the semi-empirical approach yields higher sea level 

estimates. IPCC (2013) uses coupled atmosphere-ocean general circulation models (AOGCMs) to 

simulate the processes of change rather than the statistical inferences of the semi-empirical approach. 

AOGCMs are considered a process-based technique, although some variables derive from semiempirical methods (IPCC 2013).

Sea level rise estimates for 2050 and 2100 were taken directly from the IPCC (2013) regional climate 

models (RCMs) downscaled to a spatial grid resolution of 1 ̊ x 1 ̊ from AOGCMs. Because many 

park units require estimates for shorter time horizons that fit more closely with the expected lifetime 

of various projects, sea level rise projections for 2030 were calculated using IPCC RCM data for 

each sea level rise driver shown in Table 2, interpolated to 2030 for each RCP. All projections are 

reported relative to the period 19862005 (see Appendix B for further discussion). All geographic 

information systems (GIS) maps display the projected sea level on top of mean higher-high water 

(MHHW) using the most recent tidal datum epoch (1983–2001). MHHW is calculated by averaging 

the highest daily water level over a 19-year tidal datum epoch.
7

Table 2. Median values for projections of global mean sea level rise and contributions of individual

sources, for 2100, relative to 1986-2005, in meters (IPCC 2013).

Source RCP2.6 RCP4.5 RCP6.0 RCP8.5

Thermal expansion 0.15 0.20 0.22 0.32

Glaciers 0.11 0.13 0.14 0.18

Greenland ice sheet surface mass balancea 0.03 0.05 0.05 0.10

Antarctic ice sheet surface mass balance -0.02 -0.03 -0.03 -0.05

Greenland ice sheet rapid dynamics 0.04 0.04 0.04 0.05

Antarctic ice sheet rapid dynamics 0.08 0.08 0.08 0.08

Land water storage 0.05 0.05 0.05 0.05

Sea level rise 0.44 0.53 0.55 0.74

aChanges in ice mass derived through direct observation and satellite data.

The standard error (σ) for each site estimate was not calculated because it was beyond the scope of 

this project. However, it can be calculated using the following equation and data available from the 

IPCC (2013, supplementary material):

Eq 1. σtot

2 = (σsteric/dyn + σsmb_a + σsmb_g)

2

+ σglac

2 + σIBE

2 + σGIA

2 + σLW

2 + σdyn_a

2 + σdyn_g2

Where: steric/dyn = the global thermal expansion uncertainty plus dynamic sea surface height; smb_a

= the Antarctic ice sheet surface mass balance uncertainty; smb_g = the Greenland ice sheet surface 

mass balance uncertainty; glac = glacier uncertainty; IBE = the inverse barometer effect uncertainty;

GIA = global isostatic adjustment; LW = the land water uncertainty; dyn_a = Antarctica ice sheet 

rapid dynamics uncertainty; and, dyn_g = Greenland ice sheet rapid dynamics uncertainty.

Initial data were exported as GeoTIFF files for use in ArcGIS. For parks that crossed more than one 

pixel, an average sea level rise was calculated by weighting pixel values by the length of park 

shoreline in each pixel. A standard bathtub model approach was used to identify areas of projected 

inundation and flooding. In this method, projected sea level under climate change was determined by 

adding the IPCC RCM value to the current mean higher high water level. The land that would be at 

or below a projected sea level was then determined by analyzing digital elevation models (DEMs) of

land elevation at spatial resolutions of 500 to 7000 m, depending on data availability for the areas of 

each park. DEM data for most regions were gathered from the NOAA digital coast website

(https://coast.noaa.gov/digitalcoast). Areas of inundation and flooding are denoted in the maps 

(Appendix A) in blue. Additional low-lying areas that could be potentially inundated or flooded are 

shown in green (Figure 2). These low-lying areas do not appear to have any inlet or other pathway 

for water (based on our elevation datasets), although they should still be considered vulnerable to 

exposure to either groundwater seepage or potential flooding via breaching. The lack of highresolution DEMs and time constraints prevented us from attempting a dynamic modeling approach 

(see limitations below). Maps were created to illustrate inundation for all park units for 2050 and 
8

2100 under RCP4.5 and RCP8.5. These two represent a plausible range of scenarios between 

significant policy response (RCP4.5) and business as usual (RCP8.5).

Figure 2. An example of how areas of inundation appear in ArcGIS. In this example for the Toms Cove 

area of Assateague Island National Seashore, areas of inundation (RCP4.5 2050) appear in blue. Green 

shading indicates other low lying areas that are blocked from inundation by some impediment, but 

nonetheless could experience flooding should the physical barrier be removed or breached.

Storm Surge Data

NOAA SLOSH data estimate potential storm surge height at current (most recent tidal datum) sea 

level (NOAA 2016). The NOAA SLOSH model comprises the following three products (P-Surge, 

MEOW, and MOMs) that utilize three different modeling approaches (probabilistic, deterministic, 

and composite) to estimate storm surge. 

P-Surge (also known as the tropical cyclone storm surge probabilities product) uses a probabilistic

approach by examining past events to estimate the storm surge generated by a cyclone that is present 

and within 72-hours of landfall. It statistically evaluates National Hurricane Center data (calculated 

in part using a deterministic approach) including the official projected cyclone track and historical 
9

forecasting errors. It also incorporates astronomical tide calculations and variations in the radius of 

maximum wind into this estimate. These rates of motion variables are then fit to a Cartesian or polar 

(depending on the location) grid (Jalesnianski et al. 1992). 

The Maximum Envelope Of Water (MEOW) calculates flooding using past SLOSH output to create 

a composite estimate of the potential storm surge generated by a hypothetical storm. This product 

generates a worst-case scenario based on a hypothetical storm category that includes forward speed, 

trajectory of the storm when it strikes the coastline, and initial (mean vs. high) tide level that will also 

incorporate any historical uncertainty from previous landfall forecasts.

The final SLOSH product is the MOM (Maximum of MEOWs) model. MOM is a further composite 

approach that uses the forward speed, trajectory, and initial tide level data that is also used by 

MEOW to create a worst-of-the-worst scenario (or “perfect storm”). Storms are simulated for 32 

regions (also known as operational basins, Figure 3) defined by NOAA. Data was imported into 

ArcGIS using the SLOSH display program. Maps were generated showing storm surge for all 

possible Saffir-Simpson hurricane categories for each site. While most sites had data for SaffirSimpson hurricane categories 15 (Table 3), a few sites, such as Acadia National Park, were missing 

the highest category. NOAA did not model this scenario because it is considered extremely unlikely

at a location that far north in the Atlantic Ocean.
10

Figure 3. An example of the extent of an operational basin shown in NOAA’s SLOSH display program 

(http://www.nhc.noaa.gov/surge/slosh.php). The black area is the full extent of the operational basin for 

Chesapeake Bay.

Table 3. Saffir-Simpson hurricane categories.

Saffir-Simpson 

Hurricane Category

Sustained Wind Speed 

(miles per hour, mph; knots, kt; kilometers per hour, km/h)

1 74–95 mph; 64–82 kt; 118–153 km/h

2 96–110 mph; 83–95 kt; 154–177 km/h

3 111–129 mph; 96–112 kt; 178–208 km/h

4 130–165 mph; 113–136 kt; 209–251 km/h

5 More than 157 mph; 137 kt; 252 km/h 

SLOSH MOM was used to estimate potential storm surge in 79 coastal park units. Unfortunately,

MOM data do not exist for the remaining 39 units, so we supplemented this with data from Tebaldi et 

al. (2012) wherever possible. Tebaldi et al. (2012) used 55 long-term tide gauge records to calculate 

potential sea level and storm surge estimates above mean high water levels. We used the current 50-

year and 100-yr return level data from their paper for any parks near a tide gauge. Unfortunately, due 

to insufficient coverage by tide gauges in this area, we were unable to use either Tebaldi et al. (2012) 
11

or SLOSH MOM data for the Alaska, Guam, Saipan, and American Samoa park units. It is important 

to note that the Tebaldi et al. (2012) and SLOSH MOM data differ in their methods of calculation 

making it inadvisable to compare storm surge values from the Pacific West Region to other regions. 

However, this method had to be used due to the lack of SLOSH MOM data for the Pacific West 

Region.

We recommend that parks planning for future hurricanes use information from one hurricane 

category higher than any previous storm experienced. Historical hurricane data from the International 

Best Track Archive for Climate Stewardship (IBTrACS; Knapp et al. 2010) is listed in Appendix D 

(Table D3) to allow staff to determine the highest Saffir-Simpson category hurricane to strike within 

10 miles of each park unit. Applying information from one storm category higher than historical data 

may more closely approximate what could happen in the future, as storms are projected to be more 

intense under continued climate change (Emanuel 2005, Webster 2005, Mendelsohn et al. 2012). 

However, we recommend caution in using this approach for any detailed (site-level) planning due to 

limitations discussed in the following section of this report.

Limitations

All projects of this nature have limitations that should be clearly described to ensure appropriate use 

and interpretation of these data.

Every effort has been made to incorporate any parks established after this project began (e.g. Harriet 

Tubman Underground Railroad National Monument); however, some maps might be missing due to 

lack of available boundary data in new units.

Sea level and storm surge estimates were derived using separate programs from the IPCC and 

NOAA, respectively. These numbers were then imported into GIS maps using the program ArcGIS. 

We used a bathtub modeling approach to map the extent of sea level rise and storm surge over every 

unit. Bathtub modeling simply simulates how high or how far inland water will go under different 

climate change scenarios. It does not recognize changes in topography or other environmental or 

artificial systems that may exist or occur in response to encroaching water. Although the bathtub 

model is the most widely used technique for modeling inundation, it is also a simplistic approach to

simulating how sea level rise will affect a landscape (Storlazzi et al. 2013). Dynamic models could 

simulate changes in flow around buildings or estimate how topographic features such as dune 

systems may migrate in response to inundation and flooding, but dynamic models also vary, which 

can be a severe limitation in trying to standardize data for summary analysis and comparison. 

The maps provided through this analysis vary in horizontal and vertical accuracy depending on 

which digital elevation model (DEM) data were available at the time of mapping. This is discussed in 

more detail in the metadata that accompany each map. DEM data for most regions were gathered 

from the NOAA digital coast website (https://coast.noaa.gov/digitalcoast/) which uses source 

elevation data that either meet or exceed current Federal Emergency Management mapping 

specifications. These NOAA digital coast data were required to have a minimum root mean square 

error of 18.5 cm for low lying areas that were then corrected for MHHW using the NOAA VDatum 

model (Parker et al. 2003). USGS data were used for areas, such as Alaska, where digital coastal data 
12

were not available. We recommend referring to Schmid et al. (2014) for further discussion on 

potential uncertainty of this technique.

Although SLOSH MOM has the widest geographic storm surge coverage of any model in the US,

storm surge data were not available for every part of the coastline. Every effort has been made by this

project to bridge any gaps where SLOSH MOM does not exist. While the Tebaldi et al. (2012) data 

cover the California, Oregon, Washington, and southern Alaskan coastlines, they do not cover

northern Alaskan, American Samoa, Saipan, or Guam coastlines. These coastlines are vulnerable to 

storm surge but we could not find data that satisfied our standards of accuracy sufficiently to be 

included in our mapping efforts.

Furthermore, storm surge maps are only intended as a rough guide of how flooding caused by storm 

surge will look today. As more of the coastline becomes inundated we can expect coastal flooding 

patterns to also change accordingly. The SLOSH model is a multiple scenario approach that uses 

previous storms to estimate future storm surge. It cannot take into account changes in future basin 

morphology that could affect the fluid dynamics and propagation of coastal flooding.

SLOSH MOM is modeled using mean sea level (0 m NAVD88) and what NOAA terms “high tide” 

(which is not tied to the local tidal datum, but is actually a round number based on the modeled 

average high tide for the region). Jalesnianski et al. (1992) estimate surge estimates to be accurate +/-

20%, although Glahn et al. (2009) discuss how others have found the P-Surge model to be more 

accurate than originally estimated. Such factors must be kept in mind when using these numbers for 

mapping.

Land Level Change

It is important to include changes in land level while interpreting changes in sea level. The IPCC 

(2013) includes a limited amount of data regarding changes in relative sea level in their calculations

of sea level change. Our sea level rise results include the IPCC estimates of how changes in land 

level will change over time based on estimates of glacial isostatic adjustment. Land level change is 

an important variable when calculating relative sea level. Land levels have changed over time in 

response to numerous factors. Changes in various land-based loadings—such as ice sheets during the 

last glacial maximum—has been a significant cause of land level change in the U.S. Post-glacial

isostatic rebound is the result of this pressure being released after the removal of ice sheets on the 

Earth’s crust. Land level can also be altered by other factors such as tectonic shifts, particularly along 

the Alaska and continental U.S. Pacific coastlines. These drivers can often prompt a relative increase 

or decrease in land level depending on location. Other factors such as aquifer drawdown and the 

draining of coastal wetlands can create decreases in relative land level. 

Quantifying how land levels are changing is difficult given the paucity of data available prior to 

modern satellite data. An upcoming NASA publication on land-based movement (Nerem pers. 

comm.) will help to address this data need, providing numbers for land-based movement across the 

country. Data from the NASA report can then be incorporated with sea level rise numbers from this 

analysis using the following equation (after Lentz et al. 2016):
13

Eq. 2 ae = E0 – ei + R

Where; ae is the adjusted elevation, E0 is the initial land elevation, ei is the future sea level for either 

2030, 2050, or 2100, and R is the current rate of land movement over time due to isostatic 

adjustments.

In the interim, tide gauges can provide further data regarding changes in land level, but should be 

used cautiously. We have listed tide gauge data for the rate of change in land level for tide gauges 

nearest to all units for this study in Appendix D; however, only Fort Pulaski National Monument and 

Golden Gate National Recreation Area have a long-term tide gauge on site. This lack of nearby longterm data can limit the accuracy of these numbers if they are applied to sea level change projections 

for almost all other parks units. We indicate in Table D1 which of the nearest tides gauges we do not 

recommend using to estimate land movement. This is because in many cases the boundary of the 

park unit is located either too far away or on a different land mass to where the nearest tide gauge is, 

which increases the inaccuracy of this data. Land level changes were only reported for long-term tide 

gauges that had at least thirty years of data in order to ensure a statistically robust dataset. Based on 

these limited records, we estimate that seven park units are currently experiencing decreasing relative 

sea levels (Glacier Bay National Park, Glacier Bay Preserve, Katmai National Park, Kenai Fjords 

National Park, Lake Clark National Park, Sitka National Historical Park), although we cannot be 

certain of this number given that many of the park units are some distance from a tide gauge. 

A discussion of the applicability of these land level numbers (with a natural resources manager or 

similar expert) should accompany use of individual park maps from this analysis to ensure that the 

nearest tide gauge to any particular project site is appropriate. Current rates of subsidence at these 

tide gauges range between +7.6 mm/y (Grand Isle, Louisiana) and -19 mm/y (Skagway, Alaska; 

Table D1). In selecting an appropriate tide gauge to use, variables including oceanographic setting, 

length of the record, completeness of data, and geography of the coastline must be considered. The 

science team for this project decided against setting a threshold for how close a park unit should be to 

a long-term tide gauge based on considerations discussed above.

Where to Access the Data

All GIS data from this project are available at https://irma.nps.gov/Portal for archiving by park.

A website discussing this project is available at the following address:

https://www.nps.gov/subjects/climatechange/sealevelchange.htm

The raw IPCC (2013) data can be downloaded using the following link: 

http://www.ipcc.ch/report/ar5/wg1/docs/ar5_wg1_ch13sm_datafiles.zip
14

Results

Sea level and storm surge maps are in Appendix A. A full list of the 118 park units and a table listing 

sea level projections by park are available in Appendix D. Following the methods outlined above, we 

found that sea level rise projections across the 118 park units average between 0.45 m (RCP2.6) and 

0.67 m (RCP8.5) by 2100. However, this number masks how these projections will vary 

geographically. Figure 4 shows these projections in more detail and provides sea level estimates by 

region. Error bars in Figure 4 denote the standard deviation for each average per region, further 

revealing how these numbers can vary. A high standard deviation and range signals that sea level 

estimates vary between units within regions, whereas a low standard deviation and small range are to 

be expected in smaller regions where sea level rise estimates do not cover such a large geographic 

area.

Figure 4. Projected future sea level by NPS region for 2100 under RCP8.5 (the “business as usual” 

climate change scenario). Black dots indicate the average sea level rise (m) for all units within the 

respective regions. Black bars represent the standard deviation of each mean. Blue bars mark the full 

range of sea level estimates for each region.

Based on the averages per region, we found that the shoreline within the National Capital Region is 

projected to experience the highest sea level rise by 2100 (0.80 m RCP8.5), although this number 

does not include the full extent of changes in land level over the same time interval. The shoreline 

near Wright Brothers National Memorial in the Southeast Region has the highest overall projected 
15

sea level rise (0.82 m, RCP8.5, 2100). Glacier Bay Preserve and Klondike Gold Rush National 

Historical Park are tied for lowest projected sea level rise at 0.33 m using RCP8.5 for 2100. The 

Alaska Region also has the highest standard deviation among park units. The National Capital 

Region conversely has very little standard deviation due to the compact nature of the region

(meaning that all of the parks units fell within the same raster cell). This is not to say that all of the 

parks will experience exactly the same rate of sea level rise, but that the IPCC model projected that 

sea levels could rise up to an average 0.80 m (RCP8.5) for that region by 2100. The sea level rise 

maps (discussed in the National Capital section below) illustrate differences among the National 

Capital parks in more detail.

Comparing RCP8.5 data for 2030 and 2050 (Figures 5 and 6, respectively) shows the Northeast 

Region almost tied with the National Capital Region in 2030 based on average projected sea level 

rise, with the National Capital Region ranked highest. The Alaska Region ranks lowest for all three 

time intervals followed by the Pacific Northwest region, Intermountain Region, and Southeast 

Region. The Northeast Region ranks second highest for 2050 and 2100.

Figure 5. Projected future sea level rise by NPS region for 2030 under RCP8.5 (the “business as usual” 

climate change scenario). Black dots indicate the average sea level rise (m) for all units within the 

respective regions. Black bars represent the standard deviation of each mean. Blue bars mark the full

range of sea level estimates for each region. 
16

Figure 6. Projected future sea level rise by NPS region for 2050 under RCP8.5 (the “business as usual” 

climate change scenario). Black dots indicate the average sea level rise (m) for all units within the 

respective regions. Black bars represent the standard deviation of each mean. Blue bars mark the full 

range of sea level estimates for each region.

Storm surge was mapped for 79 park units. We list data for one storm category higher than the 

highest historical storm in Table D3 in Appendix D. Some (31) park units did not have a historical 

storm path occurrence within 10 miles of their boundaries, so a Saffir-Simpson hurricane 1 was 

simulated for these locations. The lack of a historical storm does not mean that these parks are not 

subject to strong storms. It may merely be that these parks are in regions that either do not have 

extensive historical records or they experience strong storms, such as nor’easters, that behave 

differently and are not part of the NOAA database.

The Southeast Region has the strongest historical hurricanes (average of highest recorded storm 

categories = 2.79), followed by the Intermountain Region (average = 2.33), National Capital Region 

(average = 1.90), and the Northeast (average = 1.03). None of the historical data intersected with the 

10-mile (16.1 km) buffers around the Alaska Region parks. The Pacific West Region has experienced 

some tropical depressions, particularly in Hawaii, but most of their storm surges are driven by other 

phenomena, such as mid-latitude cyclones or extreme tides (sometimes colloquially referred to as 

king tides). The strongest (highest winds) and most intense (lowest pressure at landfall) recorded 

historical storm to have impacted a park unit was the “Labor Day Hurricane” that passed within 10 

miles of Everglades National Park in 1935. While this storm may have been the highest intensity 

storm, it is certainly not the most damaging or costly storm in National Park Service history.
17

Northeast Region

Colonial National Historical Park, Fort Monroe National Monument, and Petersburg National 

Battlefield have the highest projected sea level rise in 2050 and 2100, and, together with Edgar Allen 

Poe National Historic Site, Fort McHenry National Monument and Historic Shrine, Independence 

National Historical Park, and Thaddeus Kosciusko National Memorial (parks near coastlines) they 

also have the highest projected sea level rise for 2030. However, while these parks may have ranked 

highly, caution should be used in applying these results. Many of these parks do not have coastline 

and so these projections are based on sea level rise for the coastline adjacent to these parks. The maps 

in Appendix A show how the projected sea level rise may affect each of these parks. Colonial 

National Historical Park, Fort McHenry, and Fort Monroe National Monument are the only park 

units of this highest rise grouping that contain coastline with their boundaries.

Figure 7 shows the range of sea level projections for the Northeast Region for 2100, averaging 

between 0.49 m (RCP2.6) and 0.74 m (RCP8.5) of sea level rise by the end of the century. Acadia 

National Park had the lowest projected rates of sea level rise for 2030 (0.080.10 m), 2050 

(0.140.19 m), and 2100 (0.280.54 m).

Figure 7. Projected future sea level rise by 2100 for the NPS Northeast Region under all of the 

representative concentration pathways. Black dots indicate the average sea level rise (m) for all units 

within the respective regions. Black bars represent the standard deviation of each mean. Blue bars mark 

the full range of sea level estimates for each category.
18

Regarding storm surge, the highest recorded storm to have travelled within 10 miles of any of the 29 

parks units identified for study was an officially unnamed hurricane in 1869 known colloquially as 

Saxby’s Gale, which was classified as a Saffir-Simpson 3 hurricane. The storm path passed presentday Boston National Historical Park and Roger Williams National Memorial. Figure 8 shows the 

estimated extent and height of a storm surge from category 3 hurricane striking Boston Harbor 

Islands National Recreation Area at mean tide.

Figure 8. Estimated storm surge created by Saffir-Simpson category 3 hurricane occurring at high tide 

near Boston Harbor Islands National Recreation Area. Colored areas represent areas of flooding. Colors 

from green to red show estimated height of a storm surge (see inset legend for estimated range).

Southeast Region

Historically, the Southeast Region has the highest intensity storms (highest Saffir-Simpson storm 

category); Everglades National Park has recorded a category 5 hurricane within 10 miles of its

boundary, the colored areas in Figure 9 indicate the potential height and extent of a storm generated 

by two different categories of hurricane. A category 2 hurricane could completely flood the park.

Future storm surges will be exacerbated by future sea level rise nationwide; this could be especially 

dangerous for the Southeast Region where they already experience hurricane-strength storms. 
19

Moreover, sea level rise projections only include changes in land movement due to glacial isostatic 

adjustment and do not include the full range of drivers of potential changes in land level. Using Table 

D1 from Appendix D as a rough guide, changing land level for parks near tide gauges can be 

evaluated. For example, the Eugene Island, Louisiana tide gauge’s current rate of sea level rise is the 

highest in the country at 9.65 mm/y, owing in part to the large rate of subsidence in the region

(Figure 1). Using the nearest tide gauge to Jean Lafitte National Historical Park and Preserve (Grand 

Isle, Louisiana, gauge 8761724) we can estimate that land will subside by 7.60 mm/y. Applying this 

estimate of subsidence (using a baseline of 1992) to our RCP8.5 projections, the park could 

experience approximately 0.41 m of relative sea level rise by 2030 followed by 0.69 m by 2050 and 

1.50 m by 2100. This is an inexact estimate of the land movement for the park given that Jean Lafitte 

National Historical Park and Preserve is approximately 60 miles (97 km) from the tide gauge; still, 

factoring in changes in land level, we can see that relative change in sea level is more than double the 

projected change in sea level using the IPCC estimates alone.

This analysis projects that, by 2100, the shoreline adjacent to Wright Brothers National Memorial 

may have the greatest sea level rise among the Southeast Region’s parks (0.82 m RCP8.5). Given 

elevations within the park, this may not inundate a large area of the memorial, unless combined with 

other factors such as a storm surge. For example, the park may be almost completely flooded if a 

category 2 or higher hurricane strikes on top of inundation from sea level rise.

Nearby parks in the Outer Banks Group, including Cape Hatteras and Cape Lookout National 

Seashores, are projected to experience sea level rise of up to 0.79 m and 0.76 m, respectively 

(RCP8.5) by 2100, resulting in large areas of inundation. While sea level rise around these national 

seashores may not be as high as what has been projected for Wright Brothers National Memorial, 

they serve as examples of how caution must be used when using these numbers to assess which park 

units are most vulnerable to sea level rise. Other factors, such as percent of exposed land, changes in 

land movement, and adaptive capacity must also be taken into account for vulnerability analyses

(Peek et al. 2015).
20

Figure 9. SLOSH MOM storm surge maps for a Saffir-Simpson category 1 (left) versus category 2 hurricane striking Everglades National Park at 

mean tide (right). Colored areas represent areas of flooding. Colors from green to red show estimated height of a storm surge (see inset legend for 

estimated range).
21

National Capital

National Capital Region has minimal variability in projected sea level rise because all park units 

selected for study are adjacent to the same section of coastline that was modeled. Their proximity

also explains why they share the same storm history. Despite these similarities, projected sea level 

rise may affect each individual park unit differently based on local topography. The strongest storm 

recorded within 10 miles (16.1 km) of the National Capital Region parks was a Saffir-Simpson 

category 2 hurricane that struck the city in 1878. While the 1878 storm caused relatively little 

damage, we can expect a significantly larger amount of damage if a similar storm struck the city 

again given considerable development now existing in the area. Figure 10 shows the extent of 

flooding caused by a Saffir-Simpson category 2 hurricane. A storm surge measuring more than 3 m 

could travel up the Potomac River causing large amounts of flooding. Such a storm surge could be

worse by the end of this century given projected sea level rise around the Capital Region of up to 0.8 

m.

Figure 10. A SLOSH MOM map showing storm surge height and extent created by a Saffir-Simspon 

category 2 hurricane striking the Washington D.C. region at high tide. Colored areas represent areas of 

flooding. Colors from green to red show estimated height of a storm surge (see inset legend for estimated 

range).
22

IPCC/SLOSH models showed either storm surge or sea level rise (or some combination of the two) 

affecting every National Capital Region park included in this analysis, with the exception of Harpers 

Ferry National Historical Park. Our mapping efforts revealed that Harpers Ferry National Historical 

Park (located approximately 149 m above sea level) is unlikely to experience any impacts of sea 

level rise due to its elevation and is unlikely to be damaged by storm surge from a hurricane, given 

its relatively protected location behind several dams along the Potomac and Shenandoah Rivers. 

Sea level rise alone is not expected to spread very far into Washington D.C., although a large section 

on the east side of Theodore Roosevelt Island could be inundated. However, storm surge flooding on 

top of this sea level rise would have widespread impacts.

Intermountain Region

The Intermountain Region covers mostly inland park units stretching from Texas to Montana. Within 

the region, only three park units in Texas are subject to sea level change: Big Thicket National 

Preserve, Palo Alto Battlefield National Historical Park, and Padre Island National Seashore. Of 

these, Padre Island National Seashore may experience the greatest effects of sea level and storm 

surge; sea level is projected to rise 0.460.69 m (RCP2.68.5, Figure 11) by 2100. The same amount 

of sea level rise is projected for the shoreline near Palo Alto Battlefield National Historical Park, but 

inundation is not projected to extend far enough to reach the park. Palo Alto Battlefield National 

Historical Park has no history of being within 10 miles of any hurricane, making the site unlikely to 

be flooded by storm surge. SLOSH MOM models for the park unit show that that the region would 

have to have either a Saffir-Simpson category 4 hurricane striking at high tide or a category 5 

hurricane striking at any tide in order for the park to experience any storm surge. On the other hand, 

Figure 12 shows that Padre Island National Seashore, located to the east of Palo Alto Battlefield 

National Historical Park, historically was within 10 miles of a category 4 hurricane. SLOSH MOM 

data show that should a category 4 hurricane occur here again, it would likely flood almost the entire 

island. 

Storm surge could potentially travel up the Neches River and flood the southernmost part of Big 

Thicket National Preserve, although both artificial and natural storm surge defenses in Beaumont, 

Texas, to the south of the preserve, may buffer it from any surge.
23

Figure 11. Projected future sea level rise by 2100 for the NPS Intermountain Region under all of the 

representative concentration pathways. Black dots indicate the average sea level rise (m) for all units 

within the respective regions. Black bars represent the standard deviation from each mean. Blue bars 

mark the full range of sea level estimates for each category.
24

Figure 12. A SLOSH MOM map showing storm surge height and extent created by a Saffir-Simspon 

category 4 hurricane striking the southwestern Texas region at mean tide. The dark green line around the 

island represents the boundary of Padre Island National Seashore. Colored areas represent areas of 

flooding. Colors from green to red show estimated height of a storm surge (see inset legend for estimated 

range).
25

Pacific West Region

The Pacific West Region identified 24 park units for analysis in this study that could be vulnerable to 

sea level rise and/or storm surge. These units occur over a large area that includes California, 

Oregon, Washington, Hawaii, American Samoa, Saipan, and Guam. War in the Pacific National 

Historical Park in Guam has the highest projected sea level rise at 0.68 m (RCP8.5) by 2100, and 

shares the highest projected sea level rise with almost all of the Hawaiian park units in 2030 and 

2050. The average projected sea level rise range is 0.400.58 m (RCP2.68.5) by 2100 for the whole 

region; high standard deviations (0.04 m and 0.08 m for RCP2.6 and RCP8.5, respectively) indicate

that park-specific projections vary widely across the region.

At the other end of the spectrum, projected sea level rise around Washington’s Olympic Peninsula 

and in the San Juan Islands, affecting Ebey’s Landing National Historical Reserve, Olympic National 

Park, and San Juan Island Historical Park, is expected to occur more slowly, reaching a maximum 

0.46 m (RCP8.5) by 2100. This region is subject to tectonic shifts and continuing land movement due 

to isostatic rebound, further complicating sea level projections. Long-term tide gauge records at Neah 

Bay, Washington (gauge 9443090), and Tofino, British Columbia, Canada (gauge 822-116), show 

relative sea levels currently decreasing while tide gauges in Port Angeles, Washington (gauge 

9444090), Victoria, Canada (gauge 822-101), and Seattle, Washington (gauge 9447130), show it to 

be increasing (Zervas 2009). Our projections indicate rising sea level in this region throughout this 

century, although further investigation of localized changes in land movement could shed more light 

on this matter.

Park units in the Pacific West Region need to be concerned about potential future storms that could 

travel along the eastern Pacific Ocean’s increasingly warmer waters. Because of the relative lack of 

hurricanes in this region historically, we used data from Tebaldi et al. (2012), which includes 

anomalous surges that could be created by storms, and other factors (very high tides sometimes 

referred to as king tides). Based on the Tebaldi et al. (2012) data, La Jolla, California (gauge 

9410230), has the lowest 100-year storm surge (0.95 m) and Toke Point, Washington (gauge 

9440910), has the highest 100-year storm surge (1.96 m) in the Pacific West Region. Tebaldi et al. 

(2012) did not analyze storm data for Hawaii, Guam, Saipan, or American Samoa, although 

IBTrACS (Knapp et al. 2010) does have hurricane records for these areas. Only tropical depressions 

have been recorded within 10 miles of almost all of the Hawaiian park units we analyzed (Haleakala 

National Park, Hawaii Volcanoes National Park, Kalaupapa National Historical Park, KalokoHonokohau National Historical Park, Puukohola Heiau National Historic Site, and World War II 

Valor in the Pacific National Monument).

Alaska Region

The Alaska Region has the lowest average projected sea level rise (0.280.43 m by 2100) compared 

to the five regions described above. Glacier Bay National Park and Preserve and Klondike Gold Rush 

National Historical Park in southeastern Alaska share the lowest projected sea level rise (0.33 m,

RCP8.5, 2100) while Bering Land Bridge National Preserve on the west coast of the state has the 

highest projected sea level rise (0.60 m, RCP8.5, 2100).
26

Figure 1 shows how current relative sea levels vary across the state. Land levels are rapidly rising in 

the southeast of the region due to isostatic rebound and other tectonic shifts. The net result of these 

increasing land levels is decreasing relative sea levels for at least the early part of this century.

Relative sea level in Skagway, Alaska is decreasing at an average rate of 17.6 mm/y (Zervas 2009).

Despite melting ice and other factors outlined in Table 1 that increase ocean water volume, the 

amount of rising water is insufficient to keep up with land level changes. Seven park units (Glacier 

Bay National Park, Glacier Bay National Preserve, Katmai National Park, Kenai Fjords National 

Park, Lake Clark National Park, Sitka National Historical Park) are identified as potentially having 

decreasing relative sea levels based on the nearest tide gauge data to each of these parks. None of 

these parks have long-term tide gauges with data spanning at least thirty years. A great strength of 

using the IPCC (2013) process-based model approach is that, unlike many other semi-empirical 

models, it does not rely on long-term tide gauge records to statistically project future sea levels. 

However, sea level projections in this analysis do not include changes in land level. The estimates 

that we report here represent the expected rise due to water volume expansion alone near to each of 

these park units. Table D1 shows how land levels are changing at long-term tide gauges across the 

country. However, given that all of these park units are located far from a tide gauge and that the 

region is relatively geologically complex, we do not recommend using the land movement numbers 

from the nearest tide gauge for any of the Alaskan parks.

Storm surge is also very difficult to model for this region. Historically, many of the parks had sea ice 

along the coastline that helped protect these parks from storm surge. Consequently, NOAA does not 

have SLOSH MOM models for this region. IBTrACS data (Knapp et al. 2010) show a few storm 

paths that have moved towards the region, but these types of storms typically do not make landfall 

once they move over colder waters. Alaska does hold the record for the highest intensity (lowest 

central pressure) storm (Duff 2015). A downgraded super typhoon, Nuri, struck Adak Island, Alaska,

in 2014 with recorded winds gusting up to 122 mph. It is impossible to determine an average or peak 

historical storm surge without adequate tide gauge data.
27

Discussion

Global mean sea levels have been rising since the last glacial maximum (Lambeck and Chappell 

2001, Clark and Mix 2002, Lambeck et al. 2014). Church and White (2006) estimated that twentieth 

century global sea levels rose at a rate of approximately 1.7 mm/y, although this rate accelerated over 

the latter part of the century. Slangen et al. (2016) found that emissions of greenhouse gases from 

human activities have been the primary driver of global sea level change since 1970 and that the rate 

of sea level rise has increased over time (Table 1). Satellite altimetry data shows that present-day 

global relative sea levels are increasing at approximately 3.3 mm/y (Cazenave et al. 2014, Fasullo et 

al. 2016).

The IPCC (2013) projects that, without greenhouse gas emissions reductions, this rate will increase,

and that global average sea levels could rise by 0.400.63 m (RCP2.68.5) by 2100. We used 

regional sea level projections from the IPCC (2013) generated for 2050 and 2100 in combination 

with our interpolated projections for 2030 to estimate the amount of sea level rise 118 coastal 

national park units could experience in the future. Our projections are based on the new 

representative concentration pathways (Moss et al. 2010, Figure 13), using a process-based model 

approach. 

Figure 13. Radiative forcing (see list of terms) for each of the Representative Concentration Pathways 

(RCPs). An increase in radiative forcing (due to the loading of anthropogenic gases into the atmosphere) 

will result in higher global average temperatures. RCPs replace the IPCC SRES scenarios. Note how 

RCP4.5 (yellow line) projections are slightly higher than RCP6.0 (gray line) in the early part of this 

century. Source: Meinshausen et al. 2011.

Numerous academic articles use mostly semi-empirical models (Rahmstorf 2007) to estimate sea 

level rise regions across the U.S. The IPCC (2013) lists several semi-empirical sea level rise 

estimates, all of which result in projections of future sea level that are higher than the IPCC (2013) 
28

approach. The differences in these approaches can be attributed to many factors. For example, some 

of the older papers may have higher sea level estimates because they are based on the older IPCC 

SRES scenarios (e.g. Vermeer and Rahmstorf 2009, Grinsted et al. 2010, Jevrejeva et al. 2010). 

Other papers may include input from “expert elicitations” in their sea level projections, in which 

experts provide their opinion on how much sea level (or a related factor) could rise in the future (e.g. 

Bamber and Aspinall 2013, Jevrejeva et al. 2014, Horton et al. 2014). Some published articles 

criticize the IPCC sea level estimates as being too conservative or underestimating rates of future sea 

level change (e.g. Kerr 2013, Horton et al. 2014). Church et al. (2013) addresses these criticisms by 

explaining how the IPCC define the probability and likelihood of their estimates, and so they are not 

discussed in detail here. Recent analyses by Clark et al. (2015) further support the findings of the 

IPCC.

A key strength of the methods used in this analysis lies in providing a unified approach to identify 

how sea level change may affect all coastal park units across the National Park System, rather than 

relying on sea level data generated for specific areas. Our analyses revealed that the National Capital 

Region is projected to experience the greatest increase in sea level (not taking into account changes 

in land level). This rise will affect each of the region’s units in different ways depending on the 

elevation of the individual unit, but it could be significant if combined with a storm surge from a 

storm such as the Saffir-Simpson category 2 hurricane in 1878. 

At the individual park level, IPCC projections reveal the sea level along the coastline adjacent to 

Wright Brothers National Memorial could rise up 0.82 m (RCP8.5) by 2100, which could lead to 

significant flooding if the dynamic landforms are not able to keep pace with such high rates of sea 

level rise. In addition, storm surge impacts at this higher sea level would be significant. The 

Southeast Region as a whole is generally susceptible to inundation and flooding due to its low-lying 

nature in many places, particularly in Cape Hatteras and Cape Lookout National Seashores. Our sea 

level rise maps (Appendix A) highlight how much all of these park units may be affected.

These estimates do not include the latest data on changing land levels. The IPCC included estimates 

of global isostatic adjustment (Equation 1) in their predictions, but those do not include changes in 

land level due to other factors, such as earthquakes and groundwater extraction. We can roughly 

estimate relative sea level change for a small number of parks based on current rates of subsidence 

gathered from nearby long-term tide gauge data. We project Jean Lafitte National Historical Park and 

Preserve to have the greatest relative sea level increase based on the current rate of land movement.

Our sea level projections agree with current sea level trends in showing that the southeast Alaska 

region is experiencing the least amount of sea level rise of anywhere in the National Park System.

Sallenger et al. (2012) discussed how changes in Atlantic Ocean temperatures and salinity (resulting 

from changes in circulation) could lead to changes in sea level that could create a 1000-km long 

“hotspot” along the North Atlantic coast from Cape Cod, Massachusetts to Cape Hatteras, North 

Carolina. We estimate that almost all of the coastal park units in this area would be flooded under 

these conditions.
29

It is unknown exactly to what degree future storm surge will affect the Alaskan park units. Accurate 

long-term (>30 years) storm surge data do not exist for the Alaska region. Even if such data did exist,

it would be not be analogous to future conditions in the region because sea ice that had previously 

protected the shores for many of the western Alaska park units melts to reveal an easily erodible 

coastline (Frey et al. 2015). The warming of ocean waters in the Gulf of Alaska and Pacific Ocean

could also make it more conducive for more storms like Typhoon Nuri to travel north without losing 

energy as under historic conditions.

The Pacific West Region shows high variability among parks. War in The Pacific National Historical 

Park in Guam ranks highest in projected sea level rise among units in the Pacific West Region. The 

large area of the region partly explains the relatively high standard deviation in results for the region. 

The tectonically complex setting of many of the region’s parks also complicates future sea level 

estimates. Changes in land movement are somewhat gradual nationwide in comparison to Alaska and 

the Pacific West Region, especially where earthquakes can rapidly change the position of the land 

relative to the sea.

Island park units in general are particularly exposed to the impacts of sea level change and storm 

surge. Many of the barrier island parks, such as Fire Island National Seashore, Assateague Island 

National Seashore, Padre Island National Seashore, Gulf Islands National Seashore, and Cape 

Hatteras National Seashore, are all projected to experience sea level rise of over 0.69 m by 2100 

(RCP8.5). This sea level rise, combined with storm surge, could be especially difficult for isolated 

island park units, such as the Caribbean park units, the National Park of American Samoa, and War 

in the Pacific National Historical Park, where access to aid in the event of a natural disaster may not 

be immediately available. 
30

Conclusions

This report presents projections of sea level change (118 parks) and storm surge (79 parks) in coastal 

park units administered by the National Park Service. Sea level change and storm surge vary 

geographically, resulting in locally-specific challenges for adaptation and management. It is 

important to acknowledge that sea level change will affect some parts of Alaska differently than 

coastal parks in the rest of the country. Northwest Alaska can expect relative sea levels to increase

over time; while in southeast Alaska, relative sea levels may continue to decrease over the first part 

of this century, followed by an increase in relative sea level towards the end of the century.

This project is an important first step in assessing how changes in sea level and storm surge may 

affect national park units. Using sea level rise and storm surge information, parks can begin to plan 

for effects on resources, facilities, access, and other areas of management. While methods used here

are not appropriate for combining the separate sea level rise and storm surge results, parks should be 

aware of the potential for synergistic effects of sea level rise and storm surge causing impacts larger 

than either may cause individually. It is clear that more research can be done on these complex issues 

to assess how these changes may affect parks and regions. These data can inform future projects 

related to both natural and cultural resources as well as the planning and management of 

infrastructure.
31

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A-1

Appendix A 

Links to Data Sources

Maps were created for this project using NOAA DEM data. For further information regarding our 

methods refer to methods section on page 3.

Digital versions of our sea level rise maps will be available at https://irma.nps.gov/Portal

Storm surge maps are also available on https://irma.nps.gov/Portal and 

www.flickr.com/photos/125040673@N03/albums/with/72157645643578558
B-1

Appendix B

Frequently Asked Questions

Q. How were the parks in this project selected?

A. Parks were selected after consultation with regional managers. Regional managers were 

given a list of parks that authors considered to be vulnerable to sea level change and/or storm 

surge. This list was vetted by regional managers and their staff who added or subtracted park 

names based on their knowledge of the region.

Q. What was the process and timeline of this project?

A. This is the culmination of a multi-year project that was initiated in 2013. Collaboration 

between the National Park Service and the University of Colorado Boulder led to development of 

the report, associated data, and GIS files. External peer review of this report was conducted in 

late 2016 and early 2017. Management review extended into early 2018. A data visualization 

viewer is still in development.

Q. In what instance did you use data from Tebaldi et al. (2012)?

A. NOAA’s Sea Lake and Overland Surge from Hurricanes (SLOSH) model does not include 

storm surge predictions for all of the parks used in this study. We used data from Tebaldi et 

al. (2012) where reasonable to provide data for park units in California, Oregon, Washington, 

and southern Alaska. The following parks used Tebaldi et al. (2012) data: Cabrillo National 

Monument, Channel Islands National Park, Ebey’s Landing National Historical Reserve, Fort 

Point National Historic Site, Fort Vancouver National Historic Site, Golden Gate National 

Recreation Area, Klondike Gold Rush National Historical Park, Lewis and Clark National 

Historical Park, Olympic National Park, Port Chicago Naval Magazine National Scenic Trail, 

Point Reyes National Seashore, Redwood National Park, Rosie the Riveter WWII Home 

Front National Historical Park, San Francisco Maritime National Historical Park, San Juan 

Island National Historical Park, and Santa Monica Mountains National Recreation Area.

Q. Why don’t all of the parks have storm surge maps?

A. Unfortunately some parks do not have enough data to complete a storm surge map. These 

were parks that were not modeled by NOAA’s SLOSH MOM model or near any of the tide 

gauges used by Tebaldi et al. (2012). These parks are: Aniakchak Preserve, Bering Land 

Bridge National Preserve, Cape Krusenstern National Monument, Glacier Bay National Park 

and Preserve, Katmai National Park, Kenai Fjords National Park, Lake Clark National Park, 

Sitka National Historical Park, War in the Pacific National Historical Park, and Wrangell –

St. Elias National Park and Preserve.

Q. My park only has storm surge maps covering a few Saffir-Simpson categories. Why is that?

A. Some parks, particularly those in the Northeast Region, were not modeled by NOAA for 

the full range of Saffir-Simpson storm scenarios. This is because it is considered very 

unlikely that a Saffir-Simpson category 4 or 5 hurricane would be able to sustain itself into

the northern latitudes of that region.
B-2

Q. Why are the storm surge maps in NAVD88?

A. That is the default datum for SLOSH data. This was a decision made by NOAA.

Q. What are the effects of NAVD88 on sea level and storm surge projections for some parks?

A. The North American Vertical Datum of 1988 (NAVD88) is a datum that is commonly 

used in North America to refer to the “elevation” of a location. It uses a fixed value for the 

height of North America’s mean sea level. While this is a popular datum for mapping, it has 

the limitation that it is based on the observed mean sea level for a single location: Rimouski, 

Canada. As you move further away from this location you can expect actual sea level to 

differ from the mean sea level at Rimouski. For locations such as California this can result in 

a significant difference between observed mean sea level and NAVD88. Your natural 

resource or GIS specialist will likely have further information about your specific location. 

Alternatively you can look up the differences in your region by checking the datum 

information for your nearest tide gauge station: 

https://tidesandcurrents.noaa.gov/stations.html?type=Datums

Q. Which sea level change or storm surge scenario would you recommend I use?

A. All parks are different, as are all projects. Your choice of scenario may depend on many 

different factors including risk tolerance and expected time horizon of the project. The NPS 

has not yet released any guidance on which climate change scenarios to use for planning. We 

would recommend you contact the appropriate project lead, natural or cultural resource 

manager, or someone from the Climate Change Response Program for further guidance 

depending on your situation.

Q. How accurate are these numbers?

A. The accuracy of these data varies depending on the data source. SLOSH data has +/- 20% 

accuracy, although this is discussed in greater detail by Glahn et al. (2009). Further 

information about storm surge data generated by Tebaldi et al. can be found in Tebaladi et al. 

(2012). IPCC global sea level rise projections range between 0.26 m (RCP2.6 minimum 

likely range) and 0.82 m (RCP8.5 maximum likely range) by 2100. The standard error of the 

IPCC is explained in greater detail in the Chapter 13 supplementary material in AR5 (IPCC 

2013). An explanation on the horizontal and vertical accuracy of the digital elevation models 

used for mapping can be found in the metadata that accompanies the map data on 

https://irma.nps.gov/Portal. DEM data were required to have a ≤18.5 cm root mean square 

error vertical accuracy before they were converted to MHHW. An exception to this was in 

Alaska where these data were not available.

Q. We have had higher/lower storm surge numbers in the past. Why?

A. The numbers given here are meant to represent a maximum based on a typical storm surge 

category. As described above, there is likely to be some deviation around that number. 

Certain periods are also likely to result in higher than average storm surges. For example, 

periodic changes in regional water temperatures (caused by phenomena such as El Niño and 

La Niña) will impact water levels that will add to any storm surge. Likewise, changes in the 

North Atlantic Oscillation and Pacific Decadal Oscillation will also affect ocean conditions. 
B-3

This must be taken into account when using these numbers. All of these factors vary 

temporally and geographically, so contact your natural resource manager if you are unsure 

how this could impact your particular park unit.

Q. What other factors should I consider when looking at these numbers?

A. These projections do not include the impact of all man-made structures, such as flood 

barriers, levees, and dams. They also do not take into account how smaller features, such as 

dune systems or vegetation changes could impact coastal flooding. There are many mesoand micro-scale factors that need to be taken into account such as differences in topography, 

the presence/absence of any wetlands etc. It should also be expected that as sea levels 

change, areas of the shoreline will change accordingly, particularly due to erosion and 

accretion.

Q. Why don’t you recommend that I add storm surge numbers on top of the sea level change 

numbers?

A. Higher sea level and permanent inundation will change the way waves propagate within a 

basin. Sea level change is expected to have a significant impact on the geomorphology of the 

coastline. Changing water levels will lead to areas of greater erosion in some areas as well as 

increasing accretion in other places. As sea level changes, the fluid dynamics of a particular 

region will also change. For example, tidal distance will change as water levels rise, which 

will alter the spatial extent of a storm surge as well as potentially impacting wave height. 

This is not something NOAA takes into account in their SLOSH model.

Q. Where can I get more information about the sea level models used in this study?

A. https://www.ipcc.ch/report/ar5/wg1/

Q. Where can I get more information about the NOAA SLOSH model?

A. http://www.nhc.noaa.gov/surge/slosh.php

Q. So, based on your maps, can I assume that my location will stay dry in the future?

A. No. As explained above, these numbers are accurate within a certain range. Also, these 

maps are based on “bathtub” models where water is simulated as rising over a static surface. 

In reality, your coastline will change in response to storms and other coastal dynamics. These 

numbers are intended for guidance only. 

Q. Why do you use the period 19862005 as a baseline for your sea level rise projections?

A. We are following the standard approach used by the IPCC, USACE, and much of the 

academic literature. If you would like your estimate to start from a specific year you can do 

one of two things: 1) subtract the observed rate of sea level rise since 1992 for your location, 

or 2) contact park, region, or Climate Change Response Program staff for assistance. It may 

be possible to interpolate projections further to estimate the amount of rise the models 

estimate to have taken place between the baseline and whichever year you choose. We must 

caution that if you follow option 1 you will be introducing some inaccuracy to sea level 

projections, especially if you use data from a tide gauge that is not close to your location.

Q. The SLOSH/IPCC projections seem lower/higher than X source I’ve found. Why is that?
B-4

A. Projections can vary depending on a number of factors such as choice of model, approach,

or the age of the study. We would recommend that you speak to a climate specialist when 

choosing sources.

Q. What are other impacts from sea level rise that parks should consider?

A. Impacts from sea level rise could include, but are not limited to, increased erosion, 

damaged cultural resources, damage to above and below ground infrastructure, difficulty 

accessing inundated infrastructure, increased groundwater intrusion, altered groundwater 

salinity, diminished space for recreational activities (possibly leading to conflict between 

different recreational users), and the complete loss or migration of certain coastal ecosystems. 

For more information on the topic, please see the Coastal Adaptation Strategies Handbook at: 

http://www.nps.gov/subjects/climatechange/coastalhandbook.htm
C-1

Appendix C

Data Tables

Table C1. The nearest long-term tide gauge to each of the 118 national park service units used in this report. 

Region Park Unit Nearest Tide Gauge

Is Tide Gauge 

Within The Park 

Boundary?

Length of 

Record Used 

(y)†

Rate of 

Subsidence 

(mm/y)

Northeast Region Acadia National Park Bar Harbor, ME (8413320) N 60 0.750

Assateague Island National 

Seashore‡

Lewes, DE (8557380) N 88 1.660

Boston Harbor Islands National 

Recreation Area

Boston, MA (8443970) N 86 0.840

Boston National Historical Park Boston, MA (8443970) N 86 0.840

Cape Cod National Seashore Woods Hole, MA (8447930) N 75 0.970

Castle Clinton National 

Monument

New York, The Battery, NY 

(8518750)

N 151 1.220

Colonial National Historical Park Sewells Point, VA (8638610) N 80 2.610

Edgar Allen Poe National 

Historic Site

Philadelphia, PA (8545240) N 107 1.060

Federal Hall National Memorial New York, The Battery, NY 

(8518750)

N 151 1.220

Fire Island National Seashore Montauk, NY (8510560) N 60 1.230

†Number of years used by the USACE to calculate sea level change (source: http://www.corpsclimate.us/ccaceslcurves(superseded).cfm)

‡

It is not recommended that you use this tide gauge data to determine land level for this park. The boundary is located either too far away or on a different 

land mass to where the nearest tide gauge is, which increases the inaccuracy of this data. It is strongly recommended that you wait for the forthcoming NASA 

report on land level (Nerem in prep). 

*The park boundary stretches over either large or multiple areas. More than one tide gauge record is appropriate for this park.
C2

Table C1 (continued). The nearest long-term tide gauge to each of the 118 national park service units used in this report. 

Region Park Unit Nearest Tide Gauge

Is Tide Gauge 

Within The Park 

Boundary?

Length of 

Record Used 

(y)†

Rate of 

Subsidence 

(mm/y)

Northeast Region 

(continued)

Fort McHenry National 

Monument and Historic Shrine

Baltimore, MD (8574680) N 105 1.330

Fort Monroe National 

Monument‡

Sewells Point, VA (8638610) N 80 2.610

Gateway National Recreation 

Area*‡

Sandy Hook, NJ (8531680) N 75 2.270

General Grant National 

Memorial

New York, The Battery, NY 

(8518750)

N 151 1.220

George Washington Birthplace 

National Monument‡

Solomons Island, MD (8577330) N 70 1.830

Governors Island National 

Monument‡

New York, The Battery, NY 

(8518750)

N 151 1.220

Hamilton Grange National 

Memorial

New York, The Battery, NY 

(8518750)

N 151 1.220

Harriet Tubman Underground 

Railroad National Monument 

Cambridge, MD (8571892) N 64 1.900

Independence National 

Historical Park

Philadelphia, PA (8545240) N 107 1.060

New Bedford Whaling National 

Historical Park

Woods Hole, MA (8447930) N 75 0.970

†Number of years used by the USACE to calculate sea level change (source: http://www.corpsclimate.us/ccaceslcurves(superseded).cfm)

‡

It is not recommended that you use this tide gauge data to determine land level for this park. The boundary is located either too far away or on a different 

land mass to where the nearest tide gauge is, which increases the inaccuracy of this data. It is strongly recommended that you wait for the forthcoming NASA 

report on land level (Nerem in prep). 

*The park boundary stretches over either large or multiple areas. More than one tide gauge record is appropriate for this park.
C3

Table C1 (continued). The nearest long-term tide gauge to each of the 118 national park service units used in this report. 

Region Park Unit Nearest Tide Gauge

Is Tide Gauge 

Within The Park 

Boundary?

Length of 

Record Used 

(y)†

Rate of 

Subsidence 

(mm/y)

Northeast Region 

(continued)

Petersburg National Battlefield‡ Sewells Point, VA (8638610) N 80 2.610

Roger Williams National 

Memorial

Providence, RI (8454000) N 69 0.300

Sagamore Hill National Historic 

Site

Kings Point, NY (8516945) N 76 0.670

Saint Croix Island International 

Historic Site‡

Eastport, ME (8410140) N 78 0.350

Salem Maritime National 

Historic Site

Boston, MA (8443970) N 86 0.840

Saugus Iron Works National 

Historic Site

Boston, MA (8443970) N 86 0.840

Statue of Liberty National 

Monument‡

New York, The Battery, NY 

(8518750)

N 151 1.220

Thaddeus Kosciuszko National 

Memorial

Philadelphia, PA (8545240) N 107 1.060

Theodore Roosevelt Birthplace 

National Historic Site

New York, The Battery, NY 

(8518750)

N 151 1.220

Southeast Region Big Cypress National Preserve Naples, FL (8725110) N 42 0.270

Biscayne National Park‡ Miami Beach, FL (Inactive –

8723170)

N 51 0.690

†Number of years used by the USACE to calculate sea level change (source: http://www.corpsclimate.us/ccaceslcurves(superseded).cfm)

‡

It is not recommended that you use this tide gauge data to determine land level for this park. The boundary is located either too far away or on a different 

land mass to where the nearest tide gauge is, which increases the inaccuracy of this data. It is strongly recommended that you wait for the forthcoming NASA 

report on land level (Nerem in prep). 

*The park boundary stretches over either large or multiple areas. More than one tide gauge record is appropriate for this park.
C4

Table C1 (continued). The nearest long-term tide gauge to each of the 118 national park service units used in this report. 

Region Park Unit Nearest Tide Gauge

Is Tide Gauge 

Within The Park 

Boundary?

Length of 

Record Used 

(y)†

Rate of 

Subsidence 

(mm/y)

Southeast Region 

(continued)

Buck Island Reef National 

Monument‡

San Juan, Puerto Rico 

(9755371)

N 45 -0.020

Canaveral National Seashore Daytona Beach Shores, FL 

(Inactive – 8721120)

N 59 0.620

Cape Hatteras National 

Seashore*‡

Beaufort, NC (8656483) N 54 0.790

Cape Lookout National 

Seashore

Beaufort, NC (8656483) N 54 0.790

Castillo De San Marcos National 

Monument‡

Mayport, FL (8720218) N 79 0.590

Charles Pinckney National 

Historic Site

Charleston, SC (8665530) N 86 1.240

Christiansted National Historic 

Site‡

San Juan, Puerto Rico 

(9755371)

N 45 -0.202

Cumberland Island National 

Seashore‡

Fernandina Beach, FL 

(8720030)

N 110 0.600

De Soto National Memorial St. Petersburg, FL (8726520) N 60 0.920

Dry Tortugas National Park‡ Key West, FL (8724580) N 94 0.500

Everglades National Park*‡ Miami Beach, FL (Inactive –

8723170)

N 51 0.690

†Number of years used by the USACE to calculate sea level change (source: http://www.corpsclimate.us/ccaceslcurves(superseded).cfm)

‡

It is not recommended that you use this tide gauge data to determine land level for this park. The boundary is located either too far away or on a different 

land mass to where the nearest tide gauge is, which increases the inaccuracy of this data. It is strongly recommended that you wait for the forthcoming NASA 

report on land level (Nerem in prep). 

*The park boundary stretches over either large or multiple areas. More than one tide gauge record is appropriate for this park.
C5

Table C1 (continued). The nearest long-term tide gauge to each of the 118 national park service units used in this report. 

Region Park Unit Nearest Tide Gauge

Is Tide Gauge 

Within The Park 

Boundary?

Length of 

Record Used 

(y)†

Rate of 

Subsidence 

(mm/y)

Southeast Region 

(continued)

Fort Caroline National 

Memorial‡

Fernandina Beach, FL 

(8720030)

N 110 0.600

Fort Frederica National 

Monument‡

Fernandina Beach, FL 

(8720030)

N 110 0.600

Fort Matanzas National 

Monument‡

Daytona Beach Shores, FL 

(Inactive – 8721120)

N 59 0.620

Fort Pulaski National Monument Fort Pulaski, GA (8670870) Y 72 1.360

Fort Raleigh National Historic 

Site‡

Beaufort, NC (8656483) N 54 0.790

Fort Sumter National 

Monument‡

Charleston, SC (8665530) N 86 1.240

Gulf Islands National Seashore 

(Alabama section)*‡

Dauphin Island, AL (8735180) N 41 1.220

Gulf Islands National Seashore 

(Florida section)*‡

Pensacola, FL (8729840) N 84 0.330

Jean Lafitte National Historical 

Park and Preserve‡

Grand Isle, LA (8761724) N 60 7.600

Moores Creek National 

Battlefield‡

Wilmington, NC (8658120) N 72 0.430

†Number of years used by the USACE to calculate sea level change (source: http://www.corpsclimate.us/ccaceslcurves(superseded).cfm)

‡

It is not recommended that you use this tide gauge data to determine land level for this park. The boundary is located either too far away or on a different 

land mass to where the nearest tide gauge is, which increases the inaccuracy of this data. It is strongly recommended that you wait for the forthcoming NASA 

report on land level (Nerem in prep). 

*The park boundary stretches over either large or multiple areas. More than one tide gauge record is appropriate for this park.
C6

Table C1 (continued). The nearest long-term tide gauge to each of the 118 national park service units used in this report. 

Region Park Unit Nearest Tide Gauge

Is Tide Gauge 

Within The Park 

Boundary?

Length of 

Record Used 

(y)†

Rate of 

Subsidence 

(mm/y)

Southeast Region 

(continued)

New Orleans Jazz National 

Historical Park‡

Grand Isle, LA (8761724) N 60 7.600

Salt River Bay National 

Historical Park and Ecological 

Preserve‡

San Juan, Puerto Rico 

(9755371)

N 45 -0.020

San Juan National Historic Site San Juan, Puerto Rico 

(9755371)

N 45 -0.020

Timucuan Ecological and 

Historic Preserve‡

Fernandina Beach, FL 

(8720030)

N 110 0.600

Virgin Islands Coral reef 

National Monument‡

San Juan, Puerto Rico 

(9755371)

N 45 -0.020

Virgin Islands National Park‡ San Juan, Puerto Rico 

(9755371)

N 45 -0.020

Wright Brothers National 

Memorial‡

Sewells Point, VA (8638610) N 80 2.610

National Capital Region Anacostia Park Washington, DC (8594900) N 83 1.340

Chesapeake and Ohio Canal 

National Historical Park

Washington, DC (8594900) N 83 1.340

Constitution Gardens Washington, DC (8594900) N 83 1.340

Fort Washington Park Washington, DC (8594900) N 83 1.340

†Number of years used by the USACE to calculate sea level change (source: http://www.corpsclimate.us/ccaceslcurves(superseded).cfm)

‡

It is not recommended that you use this tide gauge data to determine land level for this park. The boundary is located either too far away or on a different 

land mass to where the nearest tide gauge is, which increases the inaccuracy of this data. It is strongly recommended that you wait for the forthcoming NASA 

report on land level (Nerem in prep). 

*The park boundary stretches over either large or multiple areas. More than one tide gauge record is appropriate for this park.
C7

Table C1 (continued). The nearest long-term tide gauge to each of the 118 national park service units used in this report. 

Region Park Unit Nearest Tide Gauge

Is Tide Gauge 

Within The Park 

Boundary?

Length of 

Record Used 

(y)†

Rate of 

Subsidence 

(mm/y)

National Capital Region 

(continued)

George Washington Memorial 

Parkway

Washington, DC (8594900) N 83 1.340

Harpers Ferry National 

Historical Park

Washington, DC (8594900) N 83 1.340

Korean War Veterans Memorial Washington, DC (8594900) N 83 1.340

Lincoln Memorial Washington, DC (8594900) N 83 1.340

Lyndon Baines Johnson 

Memorial Grove on the Potomac 

National Memorial

Washington, DC (8594900) N 83 1.340

Martin Luther King Jr. Memorial Washington, DC (8594900) N 83 1.340

National Mall Washington, DC (8594900) N 83 1.340

National Mall and Memorial 

Parks

Washington, DC (8594900) N 83 1.340

National World War II Memorial Washington, DC (8594900) N 83 1.340

Piscataway Park Washington, DC (8594900) N 83 1.340

Potomac Heritage National 

Scenic Trail

Washington, DC (8594900) N 83 1.340

President’s Park (White House) Washington, DC (8594900) N 83 1.340

†Number of years used by the USACE to calculate sea level change (source: http://www.corpsclimate.us/ccaceslcurves(superseded).cfm)

‡

It is not recommended that you use this tide gauge data to determine land level for this park. The boundary is located either too far away or on a different 

land mass to where the nearest tide gauge is, which increases the inaccuracy of this data. It is strongly recommended that you wait for the forthcoming NASA 

report on land level (Nerem in prep). 

*The park boundary stretches over either large or multiple areas. More than one tide gauge record is appropriate for this park.
C8

Table C1 (continued). The nearest long-term tide gauge to each of the 118 national park service units used in this report. 

Region Park Unit Nearest Tide Gauge

Is Tide Gauge 

Within The Park 

Boundary?

Length of 

Record Used 

(y)†

Rate of 

Subsidence 

(mm/y)

National Capital Region

(continued)

Rock Creek Park Washington, DC (8594900) N 83 1.340

Theodore Roosevelt Island Park Washington, DC (8594900) N 83 1.340

Thomas Jefferson Memorial Washington, DC (8594900) N 83 1.340

Vietnam Veterans Memorial Washington, DC (8594900) N 83 1.340

Washington Monument Washington, DC (8594900) N 83 1.340

Intermountain Region Big Thicket National Preserve‡ Sabine Pass, TX (8770570) N 49 3.850

Palo Alto Battlefield National 

Historical Park‡

Port Isabel, TX (8779770) N 63 2.160

Padre Island National 

Seashore*

Padre Island, TX (8779750) N 49 1.780

Pacific West Region American Memorial Park‡ Marianas Islands, Guam 

(Inactive – 1630000)

N 46 -2.750

Cabrillo National Monument San Diego, CA (9410170) N 101 0.370

Channel Islands National Park‡ Santa Monica, CA (9410840) N 74 -0.280

Ebey’s Landing National 

Historical Reserve‡

Friday Harbor, WA (9449880) N 73 -0.580

Fort Point National Historic Site San Francisco, CA (9414290) Y 110 0.360

†Number of years used by the USACE to calculate sea level change (source: http://www.corpsclimate.us/ccaceslcurves(superseded).cfm)

‡

It is not recommended that you use this tide gauge data to determine land level for this park. The boundary is located either too far away or on a different 

land mass to where the nearest tide gauge is, which increases the inaccuracy of this data. It is strongly recommended that you wait for the forthcoming NASA 

report on land level (Nerem in prep). 

*The park boundary stretches over either large or multiple areas. More than one tide gauge record is appropriate for this park.
C9

Table C1 (continued). The nearest long-term tide gauge to each of the 118 national park service units used in this report. 

Region Park Unit Nearest Tide Gauge

Is Tide Gauge 

Within The Park 

Boundary?

Length of 

Record Used 

(y)†

Rate of 

Subsidence 

(mm/y)

Pacific West Region 

(continued)

Fort Vancouver National Historic 

Site‡

Astoria, OR (9439040) N 82 -2.100

Golden Gate National 

Recreation Area

San Francisco, CA (9414290) N 110 0.360

Haleakala National Park*‡ Kahului, HI (1615680) N 60 0.510

Hawaii Volcanoes National 

Park*‡

Hilo, HI (1617760) N 80 1.470

Kaloko-Honokohau National 

Historical Park‡

Hilo, HI (1617760) N 80 1.470

Lewis and Clark National 

Historical Park

Astoria, OR (9439040) N 82 -2.100

National Park of American 

Samoa

Pago Pago, American Samoa 

(1770000)

N 59 0.370

Olympic National Park*‡ Seattle, WA (9447130) N 109 0.540

Point Reyes National Seashore‡ San Francisco, CA (9414290) N 110 0.360

Port Chicago Naval Magazine 

National Memorial‡

Alameda, CA (9414750) N 68 -0.780

Pu’uhonua O Honaunau 

National Historical Park*‡

Hilo, HI (1617760) N 80 1.470

†Number of years used by the USACE to calculate sea level change (source: http://www.corpsclimate.us/ccaceslcurves(superseded).cfm)

‡

It is not recommended that you use this tide gauge data to determine land level for this park. The boundary is located either too far away or on a different 

land mass to where the nearest tide gauge is, which increases the inaccuracy of this data. It is strongly recommended that you wait for the forthcoming NASA 

report on land level (Nerem in prep). 

*The park boundary stretches over either large or multiple areas. More than one tide gauge record is appropriate for this park.
C-10

Table C1 (continued). The nearest long-term tide gauge to each of the 118 national park service units used in this report. 

Region Park Unit Nearest Tide Gauge

Is Tide Gauge 

Within The Park 

Boundary?

Length of 

Record Used 

(y)†

Rate of 

Subsidence 

(mm/y)

Pacific West Region 

(continued)

Puukohola Heiau National 

Historic Site*‡

Hilo, HI (1617760) N 80 1.470

Redwood National and State 

Parks

Crescent City, CA (9419750) N 74 -2.380

Rosie the Riveter WWII Home 

Front National Historical Park*

Alameda, CA (9414750) N 68 -0.780

San Francisco Maritime 

National Historical Park

San Francisco, CA (9414290) N 110 0.360

Santa Monica Mountains 

National Recreation Area

Santa Monica, CA (9410840) N 74 -0.280

War in the Pacific National 

Historical Park‡

Marianas Islands, Guam 

(Inactive – 1630000)

N 46 -2.750

World War II Valor in the Pacific 

National Monument‡

Honolulu, HI (1612340) N 102 -0.180

Alaska Region Aniakchak Preserve*‡ Unalaska, AK (9462620) N 50 -7.250

Bering Land Bridge National 

Preserve‡

No data No data No data No data

Cape Krusenstern National 

Monument‡

No data No data No data No data

Glacier Bay National Park*‡ Juneau, AK (9452210) N 71 -14.620

†Number of years used by the USACE to calculate sea level change (source: http://www.corpsclimate.us/ccaceslcurves(superseded).cfm)

‡

It is not recommended that you use this tide gauge data to determine land level for this park. The boundary is located either too far away or on a different 

land mass to where the nearest tide gauge is, which increases the inaccuracy of this data. It is strongly recommended that you wait for the forthcoming NASA 

report on land level (Nerem in prep). 

*The park boundary stretches over either large or multiple areas. More than one tide gauge record is appropriate for this park.
C-11

Table C1 (continued). The nearest long-term tide gauge to each of the 118 national park service units used in this report. 

Region Park Unit Nearest Tide Gauge

Is Tide Gauge 

Within The Park 

Boundary?

Length of 

Record Used 

(y)†

Rate of 

Subsidence 

(mm/y)

Alaska Region 

(continued)

Glacier Bay Preserve*‡ Juneau, AK (9452210) N 71 -14.620

Katmai National Park‡ Seldovia, AK (9455500) N 43 -11.420

Kenai Fjords National Park‡ Seward, AK (9455090) N 43 -3.820

Klondike Gold Rush National 

Historical Park‡

Skagway, AK (9452400) N 63 -18.960

Lake Clark National Park‡ Seldovia, AK (9455500) N 43 -11.420

Sitka National Historical Park‡ Sitka, AK (9451600) N 83 -3.710

Wrangell – St. Elias National 

Park‡

Cordova, AK (9454050) N 43 3.450

Wrangell – St. Elias National 

Preserve‡

Cordova, AK (9454050) N 43 3.450

†Number of years used by the USACE to calculate sea level change (source: http://www.corpsclimate.us/ccaceslcurves(superseded).cfm)

‡

It is not recommended that you use this tide gauge data to determine land level for this park. The boundary is located either too far away or on a different 

land mass to where the nearest tide gauge is, which increases the inaccuracy of this data. It is strongly recommended that you wait for the forthcoming NASA 

report on land level (Nerem in prep). 

*The park boundary stretches over either large or multiple areas. More than one tide gauge record is appropriate for this park.
C-12

Table C2a. Sea level rise numbers by NPS unit for the Northeast Region. Values are reported in meters. See table footnotes for further details.

Park Unit Year RCP2.6 RCP4.5 RCP6.0 RCP8.5

Acadia National Park 2030 0.08 0.09 0.09 0.1

2050 0.14 0.16 0.16 0.19

2100 0.28 0.36 0.39 0.54

Assateague Island National 

Seashore§

2030 0.15 0.15 0.15 0.14

2050 0.26 0.27 0.26 0.28

2100 0.53 0.63 0.66 0.8

Boston Harbor Islands National 

Recreation Area

2030 0.11‡ 0.11 0.11‡ 0.11

2050 0.19‡ 0.2 0.20‡ 0.22

2100 0.37‡ 0.45 0.50‡ 0.62

Boston National Historical Park 2030 0.11‡ 0.11 0.11‡ 0.11

2050 0.19‡ 0.2 0.20‡ 0.22

2100 0.37‡ 0.45 0.50‡ 0.62

Cape Cod National Seashore§ 2030 0.13 0.15 0.13 0.15

2050 0.23 0.27 0.23 0.29

2100 0.45 0.51 0.57 0.69

Castle Clinton National 

Monument*

2030 0.15 0.14 0.14 0.14

2050 0.26 0.25 0.25 0.27

2100 0.52 0.58 0.62 0.77

Colonial National Historical Park 2030 0.16 0.15 0.15 0.15

2050 0.27 0.28 0.27 0.29

2100 0.55 0.64 0.67 0.81

*Parks that do not have shoreline. These numbers are for the nearest shoreline to the park.

†Parks that are likely to be significantly impacted by changes in land level that could result decreasing relative sea level in the short term followed by increased

relative sea level by the end of the century. Refer to section methods for more information.

‡No data was available for this scenario. Data from an adjacent cell was used in lieu.

§Parks that cover two or more cells. Data were averaged between these parks based on percentage of shoreline in each cell. Adjacent cells were used in

cases where boundaries crossed into null data cells.
C-13

Table C2a (continued). Sea level rise numbers by NPS unit for the Northeast Region. Values are reported in meters. See table footnotes for 

further details.

Park Unit Year RCP2.6 RCP4.5 RCP6.0 RCP8.5

Edgar Allen Poe National 

Historic Site*

2030 0.16‡ 0.15 0.15‡ 0.14

2050 0.27‡ 0.27 0.27‡ 0.28

2100 0.54‡ 0.62 0.68‡ 0.79

Federal Hall National Memorial* 2030 0.15 0.14 0.14 0.14

2050 0.26 0.25 0.25 0.27

2100 0.52 0.58 0.62 0.77

Fire Island National Seashore§ 2030 0.14 0.14 0.14 0.14

2050 0.25 0.26 0.25 0.27

2100 0.5 0.58 0.62 0.76

Fort McHenry National 

Monument and Historic Shrine

2030 0.16‡ 0.15 0.15‡ 0.14

2050 0.27‡ 0.27 0.27‡ 0.28

2100 0.54‡ 0.62 0.68‡ 0.79

Fort Monroe National Monument 2030 0.16 0.15 0.15 0.15

2050 0.27 0.28 0.27 0.29

2100 0.55 0.64 0.67 0.81

Gateway National Recreation 

Area

2030 0.15 0.14 0.14 0.14

2050 0.26 0.25 0.25 0.27

2100 0.52 0.58 0.62 0.77

*Parks that do not have shoreline. These numbers are for the nearest shoreline to the park.

†Parks that are likely to be significantly impacted by changes in land level that could result decreasing relative sea level in the short term followed by increased

relative sea level by the end of the century. Refer to section methods for more information.

‡No data was available for this scenario. Data from an adjacent cell was used in lieu.

§Parks that cover two or more cells. Data were averaged between these parks based on percentage of shoreline in each cell. Adjacent cells were used in

cases where boundaries crossed into null data cells.
C-14

Table C2a (continued). Sea level rise numbers by NPS unit for the Northeast Region. Values are reported in meters. See table footnotes for 

further details.

Park Unit Year RCP2.6 RCP4.5 RCP6.0 RCP8.5

General Grant National 

Memorial*

2030 0.15 0.14 0.14 0.14

2050 0.26 0.25 0.25 0.27

2100 0.52 0.58 0.62 0.77

George Washington Birthplace 

National Monument

2030 0.15 0.15 0.15 0.14

2050 0.26 0.27 0.26 0.28

2100 0.53 0.63 0.66 0.8

Governors Island National 

Monument

2030 0.15 0.14 0.14 0.14

2050 0.26 0.25 0.25 0.27

2100 0.52 0.58 0.62 0.77

Hamilton Grange National 

Memorial*

2030 0.15 0.14 0.14 0.14

2050 0.26 0.25 0.25 0.27

2100 0.52 0.58 0.62 0.77

Harriet Tubman Underground 

Railroad National Monument

2030 0.15 0.15 0.15 0.14

2050 0.26 0.27 0.26 0.28

2100 0.53 0.63 0.66 0.8

Independence National 

Historical Park*

2030 0.16‡ 0.15 0.15‡ 0.14

2050 0.27‡ 0.27 0.27‡ 0.28

2100 0.54‡ 0.62 0.68‡ 0.79

*Parks that do not have shoreline. These numbers are for the nearest shoreline to the park.

†Parks that are likely to be significantly impacted by changes in land level that could result decreasing relative sea level in the short term followed by increased

relative sea level by the end of the century. Refer to section methods for more information.

‡No data was available for this scenario. Data from an adjacent cell was used in lieu.

§Parks that cover two or more cells. Data were averaged between these parks based on percentage of shoreline in each cell. Adjacent cells were used in

cases where boundaries crossed into null data cells.
C-15

Table C2a (continued). Sea level rise numbers by NPS unit for the Northeast Region. Values are reported in meters. See table footnotes for 

further details.

Park Unit Year RCP2.6 RCP4.5 RCP6.0 RCP8.5

New Bedford Whaling National 

Historical Park*

2030 0.13 0.13 0.12 0.13

2050 0.22 0.23 0.22 0.25

2100 0.45 0.53 0.55 0.7

Petersburg National Battlefield* 2030 0.16 0.15 0.15 0.15

2050 0.27 0.28 0.27 0.29

2100 0.55 0.64 0.67 0.81

Roger Williams National 

Memorial*

2030 0.13 0.13 0.12 0.13

2050 0.22 0.23 0.22 0.25

2100 0.45 0.53 0.55 0.7

Sagamore Hill National Historic 

Site

2030 0.15 0.14 0.14 0.14

2050 0.26 0.25 0.25 0.27

2100 0.52 0.58 0.62 0.77

Saint Croix Island International 

Historic Site

2030 0.15 0.14 0.14 0.14

2050 0.26 0.26 0.26 0.27

2100 0.52 0.59 0.64 0.76

Salem Maritime National 

Historic Site

2030 0.11‡ 0.11 0.11‡ 0.11

2050 0.19‡ 0.2 0.20‡ 0.22

2100 0.37‡ 0.45 0.50‡ 0.62

*Parks that do not have shoreline. These numbers are for the nearest shoreline to the park.

†Parks that are likely to be significantly impacted by changes in land level that could result decreasing relative sea level in the short term followed by increased

relative sea level by the end of the century. Refer to section methods for more information.

‡No data was available for this scenario. Data from an adjacent cell was used in lieu.

§Parks that cover two or more cells. Data were averaged between these parks based on percentage of shoreline in each cell. Adjacent cells were used in

cases where boundaries crossed into null data cells.
C-16

Table C2a (continued). Sea level rise numbers by NPS unit for the Northeast Region. Values are reported in meters. See table footnotes for 

further details.

Park Unit Year RCP2.6 RCP4.5 RCP6.0 RCP8.5

Saugus Iron Works National 

Historic Site

2030 0.11‡ 0.11 0.11‡ 0.11

2050 0.19‡ 0.2 0.20‡ 0.22

2100 0.37‡ 0.45 0.50‡ 0.62

Statue of Liberty National 

Monument

2030 0.15 0.14 0.14 0.14

2050 0.26 0.25 0.25 0.27

2100 0.52 0.58 0.62 0.77

Thaddeus Kosciuszko National 

Memorial*

2030 0.16‡ 0.15 0.15‡ 0.14

2050 0.27‡ 0.27 0.27‡ 0.28

2100 0.54‡ 0.62 0.68‡ 0.79

Theodore Roosevelt Birthplace 

National Historic Site*

2030 0.15 0.14 0.14 0.14

2050 0.26 0.25 0.25 0.27

2100 0.52 0.58 0.62 0.77

*Parks that do not have shoreline. These numbers are for the nearest shoreline to the park.

†Parks that are likely to be significantly impacted by changes in land level that could result decreasing relative sea level in the short term followed by increased

relative sea level by the end of the century. Refer to section methods for more information.

‡No data was available for this scenario. Data from an adjacent cell was used in lieu.

§Parks that cover two or more cells. Data were averaged between these parks based on percentage of shoreline in each cell. Adjacent cells were used in

cases where boundaries crossed into null data cells.
C-17

Table C2b. Sea level rise numbers by NPS unit for the Southeast Region. Values are reported in meters. See table footnotes for further details.

Park Unit Year RCP2.6 RCP4.5 RCP6.0 RCP8.5

Big Cypress National Preserve§ 2030 0.13 0.13 0.12 0.13

2050 0.23 0.24 0.22 0.24

2100 0.46 0.54 0.55 0.69

Biscayne National Park 2030 0.14‡ 0.13 0.12 0.12

2050 0.24‡ 0.23 0.21 0.24

2100 0.47‡ 0.53 0.53 0.68

Buck Island Reef National 

Monument

2030 0.13 0.12 0.11 0.12

2050 0.22 0.22 0.2 0.23

2100 0.44 0.5 0.51 0.64

Canaveral National Seashore 2030 0.14‡ 0.13 0.13‡ 0.12

2050 0.25‡ 0.24 0.24‡ 0.24

2100 0.50‡ 0.54 0.59‡ 0.68

Cape Hatteras National 

Seashore

2030 0.15‡ 0.15 0.15 0.14

2050 0.26‡ 0.28 0.28 0.28

2100 0.53‡ 0.63 0.68 0.79

Cape Lookout National 

Seashore§

2030 0.15 0.15 0.15 0.14

2050 0.26 0.27 0.26 0.27

2100 0.53 0.61 0.65 0.76

Castillo De San Marcos National 

Monument

2030 0.14 0.13 0.13 0.13

2050 0.24 0.24 0.23 0.25

2100 0.47 0.56 0.56 0.7

*Parks that do not have shoreline. These numbers are for the nearest shoreline to the park.

†Parks that are likely to be significantly impacted by changes in land level that could result decreasing relative sea level in the short term followed by increased

relative sea level by the end of the century. Refer to section methods for more information.

‡No data was available for this scenario. Data from an adjacent cell was used in lieu.

§Parks that cover two or more cells. Data were averaged between these parks based on percentage of shoreline in each cell. Adjacent cells were used in

cases where boundaries crossed into null data cells.
C-18

Table C2b (continued). Sea level rise numbers by NPS unit for the Southeast Region. Values are reported in meters. See table footnotes for 

further details.

Park Unit Year RCP2.6 RCP4.5 RCP6.0 RCP8.5

Charles Pinckney National 

Historic Site*

2030 0.14 0.14 0.13 0.13

2050 0.25 0.25 0.24 0.25

2100 0.49 0.57 0.59 0.72

Christiansted National Historic 

Site

2030 0.13 0.12 0.11 0.12

2050 0.22 0.22 0.2 0.23

2100 0.44 0.5 0.51 0.64

Cumberland Island National 

Seashore

2030 0.14 0.13 0.13 0.13

2050 0.24 0.24 0.23 0.25

2100 0.47 0.56 0.56 0.7

De Soto National Memorial 2030 0.14 0.13 0.13 0.13

2050 0.24 0.24 0.23 0.25

2100 0.48 0.56 0.57 0.72

Dry Tortugas National Park§ 2030 0.14 0.13 0.13 0.13

2050 0.24 0.24 0.23 0.24

2100 0.47 0.54 0.56 0.69

Everglades National Park§ 2030 0.13 0.13 0.12 0.17

2050 0.23 0.23 0.22 0.24

2100 0.46 0.53 0.54 0.68

*Parks that do not have shoreline. These numbers are for the nearest shoreline to the park.

†Parks that are likely to be significantly impacted by changes in land level that could result decreasing relative sea level in the short term followed by increased

relative sea level by the end of the century. Refer to section methods for more information.

‡No data was available for this scenario. Data from an adjacent cell was used in lieu.

§Parks that cover two or more cells. Data were averaged between these parks based on percentage of shoreline in each cell. Adjacent cells were used in

cases where boundaries crossed into null data cells.
C-19

Table C2b (continued). Sea level rise numbers by NPS unit for the Southeast Region. Values are reported in meters. See table footnotes for 

further details.

Park Unit Year RCP2.6 RCP4.5 RCP6.0 RCP8.5

Fort Caroline National Memorial 2030 0.14 0.13 0.13 0.13

2050 0.23 0.24 0.22 0.24

2100 0.47 0.56 0.56 0.7

Fort Frederica National 

Monument

2030 0.14 0.13 0.12 0.12

2050 0.23 0.24 0.22 0.24

2100 0.47 0.54 0.54 0.69

Fort Matanzas National 

Monument

2030 0.14 0.13 0.13 0.13

2050 0.23 0.24 0.22 0.24

2100 0.47 0.56 0.56 0.7

Fort Pulaski National 

Monument§

2030 0.14 0.14 0.13 0.13

2050 0.25 0.25 0.24 0.25

2100 0.49 0.57 0.59 0.72

Fort Raleigh National Historic 

Site

2030 0.15‡ 0.15 0.15 0.14

2050 0.27‡ 0.28 0.28 0.28

2100 0.53‡ 0.63 0.68 0.79

Fort Sumter National Monument 2030 0.14 0.14 0.13 0.13

2050 0.25 0.25 0.24 0.25

2100 0.49 0.57 0.59 0.72

*Parks that do not have shoreline. These numbers are for the nearest shoreline to the park.

†Parks that are likely to be significantly impacted by changes in land level that could result decreasing relative sea level in the short term followed by increased

relative sea level by the end of the century. Refer to section methods for more information.

‡No data was available for this scenario. Data from an adjacent cell was used in lieu.

§Parks that cover two or more cells. Data were averaged between these parks based on percentage of shoreline in each cell. Adjacent cells were used in

cases where boundaries crossed into null data cells.
C-20

Table C2b (continued). Sea level rise numbers by NPS unit for the Southeast Region. Values are reported in meters. See table footnotes for 

further details.

Park Unit Year RCP2.6 RCP4.5 RCP6.0 RCP8.5

Gulf Islands National Seashore§ 2030 0.14 0.13 0.13 0.13

2050 0.24 0.24 0.23 0.25

2100 0.48 0.55 0.57 0.7

Jean Lafitte National Historical 

Park and Preserve†§

2030 0.14 0.13 0.13 0.12

2050 0.24 0.23 0.23 0.24

2100 0.48 0.54 0.56 0.68

Moores Creek National 

Battlefield*

2030 0.15 0.15 0.15 0.14

2050 0.26 0.27 0.26 0.27

2100 0.53 0.61 0.65 0.76

New Orleans Jazz National 

Historical Park*

2030 0.14 0.13 0.13 0.12

2050 0.24 0.23 0.23 0.24

2100 0.48 0.54 0.56 0.68

Salt River Bay National Historic 

Park and Ecological Preserve

2030 0.13 0.12 0.11 0.12

2050 0.22 0.22 0.2 0.23

2100 0.44 0.5 0.51 0.64

San Juan National Historic Site 2030 0.12 0.12 0.11 0.12

2050 0.22 0.22 0.2 0.22

2100 0.43 0.49 0.5 0.64

*Parks that do not have shoreline. These numbers are for the nearest shoreline to the park.

†Parks that are likely to be significantly impacted by changes in land level that could result decreasing relative sea level in the short term followed by increased

relative sea level by the end of the century. Refer to section methods for more information.

‡No data was available for this scenario. Data from an adjacent cell was used in lieu.

§Parks that cover two or more cells. Data were averaged between these parks based on percentage of shoreline in each cell. Adjacent cells were used in

cases where boundaries crossed into null data cells.
C-21

Table C2b (continued). Sea level rise numbers by NPS unit for the Southeast Region. Values are reported in meters. See table footnotes for 

further details.

Park Unit Year RCP2.6 RCP4.5 RCP6.0 RCP8.5

Timucuan Ecological and 

Historic Preserve

2030 0.14 0.13 0.13 0.13

2050 0.24 0.24 0.23 0.25

2100 0.47 0.56 0.56 0.7

Virgin Islands Coral Reef 

National Monument

2030 0.13 0.12 0.11 0.12

2050 0.22 0.22 0.21 0.23

2100 0.44 0.5 0.51 0.64

Virgin Islands National Park§ 2030 0.13 0.12 0.11 0.12

2050 0.22 0.22 0.21 0.23

2100 0.44 0.5 0.51 0.64

Wright Brothers National 

Memorial*

2030 0.15‡ 0.16 0.16 0.15

2050 0.27‡ 0.29 0.28 0.29

2100 0.53‡ 0.65 0.7 0.82

*Parks that do not have shoreline. These numbers are for the nearest shoreline to the park.

†Parks that are likely to be significantly impacted by changes in land level that could result decreasing relative sea level in the short term followed by increased

relative sea level by the end of the century. Refer to section methods for more information.

‡No data was available for this scenario. Data from an adjacent cell was used in lieu.

§Parks that cover two or more cells. Data were averaged between these parks based on percentage of shoreline in each cell. Adjacent cells were used in

cases where boundaries crossed into null data cells.
C-22

Table C2c. Sea level rise numbers by NPS unit for the National Capital Region. Values are reported in meters. See table footnotes for further 

details.

Park Unit Year RCP2.6 RCP4.5 RCP6.0 RCP8.5

Anacostia Park* 2030 0.15 0.15 0.15 0.14

2050 0.26 0.27 0.26 0.28

2100 0.53 0.63 0.66 0.8

Chesapeake & Ohio Canal 

National Historical Park§

2030 0.15 0.15 0.15 0.14

2050 0.26 0.27 0.26 0.28

2100 0.53 0.62 0.66 0.79

Constitution Gardens* 2030 0.15 0.15 0.15 0.14

2050 0.26 0.27 0.26 0.28

2100 0.53 0.63 0.66 0.8

Fort Washington Park* 2030 0.15 0.15 0.15 0.14

2050 0.26 0.27 0.26 0.28

2100 0.53 0.63 0.66 0.8

George Washington Memorial 

Parkway§

2030 0.15‡ 0.15 0.15‡ 0.14

2050 0.26‡ 0.27 0.26‡ 0.28

2100 0.53‡ 0.62 0.66‡ 0.79

Harpers Ferry National 

Historical Park*§

2030 0.15 0.15 0.15 0.14

2050 0.26 0.27 0.26 0.28

2100 0.53 0.62 0.66 0.79

*Parks that do not have shoreline. These numbers are for the nearest shoreline to the park.

†Parks that are likely to be significantly impacted by changes in land level that could result decreasing relative sea level in the short term followed by increased

relative sea level by the end of the century. Refer to section methods for more information.

‡No data was available for this scenario. Data from an adjacent cell was used in lieu.

§Parks that cover two or more cells. Data were averaged between these parks based on percentage of shoreline in each cell. Adjacent cells were used in

cases where boundaries crossed into null data cells.
C-23

Table C2c (continued). Sea level rise numbers by NPS unit for the National Capital Region. Values are reported in meters. See table footnotes 

for further details.

Park Unit Year RCP2.6 RCP4.5 RCP6.0 RCP8.5

Korean War Veterans Memorial* 2030 0.15 0.15 0.15 0.14

2050 0.26 0.27 0.26 0.28

2100 0.53 0.63 0.66 0.8

Lincoln Memorial* 2030 0.15 0.15 0.15 0.14

2050 0.26 0.27 0.26 0.28

2100 0.53 0.63 0.66 0.8

Lyndon Baines Johnson 

Memorial Grove on the Potomac 

National Memorial

2030 0.15 0.15 0.15 0.14

2050 0.26 0.27 0.26 0.28

2100 0.53 0.63 0.66 0.8

Martin Luther King Jr. Memorial* 2030 0.15 0.15 0.15 0.14

2050 0.26 0.27 0.26 0.28

2100 0.53 0.63 0.66 0.8

National Mall* 2030 0.15 0.15 0.15 0.14

2050 0.26 0.27 0.26 0.28

2100 0.53 0.63 0.66 0.8

National Mall & Memorial Parks* 2030 0.15 0.15 0.15 0.14

2050 0.26 0.27 0.26 0.28

2100 0.53 0.63 0.66 0.8

*Parks that do not have shoreline. These numbers are for the nearest shoreline to the park.

†Parks that are likely to be significantly impacted by changes in land level that could result decreasing relative sea level in the short term followed by increased

relative sea level by the end of the century. Refer to section methods for more information.

‡No data was available for this scenario. Data from an adjacent cell was used in lieu.

§Parks that cover two or more cells. Data were averaged between these parks based on percentage of shoreline in each cell. Adjacent cells were used in

cases where boundaries crossed into null data cells.
C-24

Table C2c (continued). Sea level rise numbers by NPS unit for the National Capital Region. Values are reported in meters. See table footnotes 

for further details.

Park Unit Year RCP2.6 RCP4.5 RCP6.0 RCP8.5

National World War II Memorial* 2030 0.15 0.15 0.15 0.14

2050 0.26 0.27 0.26 0.28

2100 0.53 0.63 0.66 0.8

Piscataway Park* 2030 0.15 0.15 0.15 0.14

2050 0.26 0.27 0.26 0.28

2100 0.53 0.63 0.66 0.8

Potomac Heritage National 

Scenic Trail

2030 0.15 0.15 0.15 0.14

2050 0.26 0.27 0.26 0.28

2100 0.53 0.63 0.66 0.8

President’s Park (White House)* 2030 0.15 0.15 0.15 0.14

2050 0.26 0.27 0.26 0.28

2100 0.53 0.63 0.66 0.8

Rock Creek Park 2030 0.15 0.15 0.15 0.14

2050 0.26 0.27 0.26 0.28

2100 0.53 0.63 0.66 0.8

Theodore Roosevelt Island Park 2030 0.15 0.15 0.15 0.14

2050 0.26 0.27 0.26 0.28

2100 0.53 0.63 0.66 0.8

*Parks that do not have shoreline. These numbers are for the nearest shoreline to the park.

†Parks that are likely to be significantly impacted by changes in land level that could result decreasing relative sea level in the short term followed by increased

relative sea level by the end of the century. Refer to section methods for more information.

‡No data was available for this scenario. Data from an adjacent cell was used in lieu.

§Parks that cover two or more cells. Data were averaged between these parks based on percentage of shoreline in each cell. Adjacent cells were used in

cases where boundaries crossed into null data cells.
C-25

Table C2c (continued). Sea level rise numbers by NPS unit for the National Capital Region. Values are reported in meters. See table footnotes 

for further details.

Park Unit Year RCP2.6 RCP4.5 RCP6.0 RCP8.5

Thomas Jefferson Memorial* 2030 0.15 0.15 0.15 0.14

2050 0.26 0.27 0.26 0.28

2100 0.53 0.63 0.66 0.8

Vietnam Veterans Memorial* 2030 0.15 0.15 0.15 0.14

2050 0.26 0.27 0.26 0.28

2100 0.53 0.63 0.66 0.8

Washington Monument* 2030 0.15 0.15 0.15 0.14

2050 0.26 0.27 0.26 0.28

2100 0.53 0.63 0.66 0.8

*Parks that do not have shoreline. These numbers are for the nearest shoreline to the park.

†Parks that are likely to be significantly impacted by changes in land level that could result decreasing relative sea level in the short term followed by increased

relative sea level by the end of the century. Refer to section methods for more information.

‡No data was available for this scenario. Data from an adjacent cell was used in lieu.

§Parks that cover two or more cells. Data were averaged between these parks based on percentage of shoreline in each cell. Adjacent cells were used in

cases where boundaries crossed into null data cells.
C-26

Table C2d. Sea level rise numbers by NPS unit for the Intermountain Region. Values are reported in meters. See table footnotes for further 

details.

Park Unit Year RCP2.6 RCP4.5 RCP6.0 RCP8.5

Big Thicket National Preserve* 2030 0.14‡ 0.12 0.12‡ 0.12

2050 0.23‡ 0.23 0.22‡ 0.23

2100 0.47‡ 0.51 0.55‡ 0.66

Palo Alto Battlefield National 

Historical Park*§

2030 0.13 0.13 0.13 0.12

2050 0.23 0.23 0.22 0.24

2100 0.46 0.53 0.56 0.69

Padre Island National 

Seashore§

2030 0.13 0.13 0.13 0.12

2050 0.23 0.23 0.22 0.24

2100 0.46 0.53 0.56 0.69

*Parks that do not have shoreline. These numbers are for the nearest shoreline to the park.

†Parks that are likely to be significantly impacted by changes in land level that could result decreasing relative sea level in the short term followed by increased

relative sea level by the end of the century. Refer to section methods for more information.

‡No data was available for this scenario. Data from an adjacent cell was used in lieu.

§Parks that cover two or more cells. Data were averaged between these parks based on percentage of shoreline in each cell. Adjacent cells were used in

cases where boundaries crossed into null data cells.
C-27

Table C2e. Sea level rise numbers by NPS unit for the Pacific West Region. Values are reported in meters. See table footnotes for further details.

Park Unit Year RCP2.6 RCP4.5 RCP6.0 RCP8.5

American Memorial Park 2030 0.13 0.12 0.12 0.12

2050 0.22 0.22 0.22 0.24

2100 0.44 0.51 0.54 0.68

Cabrillo National Monument 2030 0.1 0.1 0.09 0.1

2050 0.17 0.17 0.17 0.19

2100 0.35 0.4 0.41 0.53

Channel Islands National Park§ 2030 0.11 0.11 0.1 0.1

2050 0.2 0.19 0.18 0.2

2100 0.39 0.44 0.46 0.57

Ebey’s Landing National 

Historical Reserve

2030 0.1 0.09 0.09 0.08

2050 0.17 0.16 0.16 0.16

2100 0.34 0.37 0.39 0.46

Fort Point National Historic Site 2030 0.11 0.1 0.1 0.1

2050 0.18 0.18 0.17 0.19

2100 0.37 0.41 0.43 0.53

Fort Vancouver National Historic 

Site*

2030 0.12 0.11 0.11 0.1

2050 0.21 0.2 0.19 0.19

2100 0.42 0.45 0.47 0.55

Golden Gate National 

Recreation Area§

2030 0.11 0.1 0.1 0.1

2050 0.19 0.18 0.17 0.19

2100 0.37 0.42 0.43 0.54

*Parks that do not have shoreline. These numbers are for the nearest shoreline to the park.

†Parks that are likely to be significantly impacted by changes in land level that could result decreasing relative sea level in the short term followed by increased

relative sea level by the end of the century. Refer to section methods for more information.

‡No data was available for this scenario. Data from an adjacent cell was used in lieu.

§Parks that cover two or more cells. Data were averaged between these parks based on percentage of shoreline in each cell. Adjacent cells were used in

cases where boundaries crossed into null data cells.
C-28

Table C2e (continued). Sea level rise numbers by NPS unit for the Pacific West Region. Values are reported in meters. See table footnotes for 

further details.

Park Unit Year RCP2.6 RCP4.5 RCP6.0 RCP8.5

Haleakala National Park 2030 0.13 0.12 0.12 0.12

2050 0.22 0.22 0.21 0.24

2100 0.44 0.5 0.52 0.67

Hawaii Volcanoes National Park 2030 0.13 0.12 0.12 0.12

2050 0.22 0.22 0.21 0.24

2100 0.44 0.5 0.52 0.67

Kalaupapa National Historical 

Park§

2030 0.13 0.12 0.12 0.12

2050 0.22 0.22 0.21 0.24

2100 0.44 0.5 0.52 0.66

Kaloko-Honokohau National 

Historical Park

2030 0.13 0.12 0.12 0.12

2050 0.22 0.22 0.21 0.24

2100 0.44 0.5 0.52 0.67

Lewis and Clark National 

Historical Park§

2030 0.12 0.1 0.1 0.1

2050 0.2 0.19 0.18 0.19

2100 0.4 0.44 0.46 0.53

National Park of American 

Samoa

2030 0.13 0.12 0.12 0.12

2050 0.22 0.22 0.21 0.23

2100 0.44 0.5 0.52 0.65

*Parks that do not have shoreline. These numbers are for the nearest shoreline to the park.

†Parks that are likely to be significantly impacted by changes in land level that could result decreasing relative sea level in the short term followed by increased

relative sea level by the end of the century. Refer to section methods for more information.

‡No data was available for this scenario. Data from an adjacent cell was used in lieu.

§Parks that cover two or more cells. Data were averaged between these parks based on percentage of shoreline in each cell. Adjacent cells were used in

cases where boundaries crossed into null data cells.
C-29

Table C2e (continued). Sea level rise numbers by NPS unit for the Pacific West Region. Values are reported in meters. See table footnotes for 

further details.

Park Unit Year RCP2.6 RCP4.5 RCP6.0 RCP8.5

Olympic National Park§ 2030 0.1 0.09 0.09 0.08

2050 0.17 0.16 0.16 0.16

2100 0.34 0.37 0.39 0.46

Point Reyes National Seashore§ 2030 0.11 0.1 0.1 0.1

2050 0.19 0.19 0.18 0.19

2100 0.38 0.43 0.45 0.55

Port Chicago Naval Magazine 

National Memorial

2030 0.11 0.1 0.1 0.1

2050 0.18 0.18 0.17 0.19

2100 0.37 0.41 0.43 0.53

Pu’uhonua O Honaunau 

National Historical Park

2030 0.13 0.12 0.12 0.12

2050 0.22 0.22 0.21 0.24

2100 0.44 0.5 0.52 0.67

Puukohola Heiau National 

Historic Site

2030 0.13 0.12 0.12 0.12

2050 0.22 0.22 0.21 0.24

2100 0.44 0.51 0.52 0.67

Redwood National and State 

Parks

2030 0.12 0.11 0.1 0.1

2050 0.2 0.19 0.18 0.2

2100 0.4 0.44 0.46 0.56

*Parks that do not have shoreline. These numbers are for the nearest shoreline to the park.

†Parks that are likely to be significantly impacted by changes in land level that could result decreasing relative sea level in the short term followed by increased

relative sea level by the end of the century. Refer to section methods for more information.

‡No data was available for this scenario. Data from an adjacent cell was used in lieu.

§Parks that cover two or more cells. Data were averaged between these parks based on percentage of shoreline in each cell. Adjacent cells were used in

cases where boundaries crossed into null data cells.
C-30

Table C2e (continued). Sea level rise numbers by NPS unit for the Pacific West Region. Values are reported in meters. See table footnotes for 

further details.

Park Unit Year RCP2.6 RCP4.5 RCP6.0 RCP8.5

Rosie the Riveter WWII Home 

Front National Historical Park

2030 0.11 0.1 0.1 0.1

2050 0.18 0.18 0.17 0.19

2100 0.37 0.41 0.43 0.53

San Francisco Maritime 

National Historical Park

2030 0.11 0.1 0.1 0.1

2050 0.18 0.18 0.17 0.19

2100 0.37 0.41 0.43 0.53

San Juan Island National 

Historical Park

2030 0.1 0.09 0.09 0.08

2050 0.17 0.16 0.16 0.16

2100 0.34 0.37 0.39 0.46

Santa Monica Mountains 

National Recreation Area§

2030 0.12 0.11 0.1 0.11

2050 0.2 0.2 0.19 0.2

2100 0.4 0.45 0.46 0.58

War in the Pacific National 

Historical Park

2030 0.13 0.12 0.12 0.12

2050 0.22 0.22 0.22 0.24

2100 0.44 0.51 0.54 0.68

World War II Valor in the Pacific 

National Monument§

2030 0.13 0.12 0.12 0.12

2050 0.22 0.22 0.21 0.23

2100 0.44 0.5 0.52 0.67

*Parks that do not have shoreline. These numbers are for the nearest shoreline to the park.

†Parks that are likely to be significantly impacted by changes in land level that could result decreasing relative sea level in the short term followed by increased

relative sea level by the end of the century. Refer to section methods for more information.

‡No data was available for this scenario. Data from an adjacent cell was used in lieu.

§Parks that cover two or more cells. Data were averaged between these parks based on percentage of shoreline in each cell. Adjacent cells were used in

cases where boundaries crossed into null data cells.
C-31

Table C2f. Sea level rise numbers by NPS unit for the Alaska Region. Values are reported in meters. See table footnotes for further details.

Park Unit Year RCP2.6 RCP4.5 RCP6.0 RCP8.5

Aniakchak Preserve§ 2030 0.09‡ 0.09 0.09 0.09

2050 0.15‡ 0.17 0.16 0.18

2100 0.31‡ 0.38 0.4 0.51

Bering Land Bridge National 

Preserve§

2030 0.11 0.11 0.1 0.11

2050 0.18 0.19 0.18 0.21

2100 0.37 0.44 0.45 0.6

Cape Krusenstern National 

Monument§

2030 0.1 0.1 0.1 0.1

2050 0.17 0.18 0.17 0.2

2100 0.35 0.42 0.43 0.58

Glacier Bay National Park†§ 2030 0.07 0.06 0.06 0.06

2050 0.11 0.11 0.11 0.12

2100 0.23 0.25 0.28 0.34

Glacier Bay Preserve† 2030 0.06 0.06 0.06 0.06

2050 0.11 0.11 0.11 0.11

2100 0.22 0.24 0.27 0.33

Katmai National Park§ 2030 0.09 0.08 0.08 0.08

2050 0.15 0.15 0.15 0.16

2100 0.31 0.34 0.37 0.47

Katmai National Preserve†§ 2030 0.09 0.08 0.08 0.08

2050 0.15 0.15 0.14 0.16

2100 0.3 0.33 0.34 0.45

*Parks that do not have shoreline. These numbers are for the nearest shoreline to the park.

†Parks that are likely to be significantly impacted by changes in land level that could result decreasing relative sea level in the short term followed by increased

relative sea level by the end of the century. Refer to section methods for more information.

‡No data was available for this scenario. Data from an adjacent cell was used in lieu.

§Parks that cover two or more cells. Data were averaged between these parks based on percentage of shoreline in each cell. Adjacent cells were used in

cases where boundaries crossed into null data cells.
C-32

Table C2f (continued). Sea level rise numbers by NPS unit for the Alaska Region. Values are reported in meters. See table footnotes for further 

details.

Park Unit Year RCP2.6 RCP4.5 RCP6.0 RCP8.5

Kenai Fjords National Park†§ 2030 0.09‡ 0.08 0.08‡ 0.08

2050 0.15‡ 0.14 0.14‡ 0.15

2100 0.30‡ 0.33 0.34‡ 0.44

Klondike Gold Rush National 

Historical Park*†§

2030 0.06‡ 0.06 0.06‡ 0.06

2050 0.11 0.11 0.11‡ 0.11

2100 0.22 0.24 0.27 0.33

Lake Clark National Park*† 2030 0.08 0.08 0.07 0.08

2050 0.14 0.14 0.13 0.15

2100 0.29 0.32 0.33 0.43

Sitka National Historical Park† 2030 0.08 0.07 0.07 0.07

2050 0.14 0.14 0.13 0.14

2100 0.28 0.31 0.33 0.41

Wrangell - St. Elias National 

Park§

2030 0.07 0.06 0.06 0.07

2050 0.12 0.12 0.11 0.12

2100 0.23 0.26 0.8 0.35

Wrangell – St. Elias National 

Preserve*§

2030 0.07 0.06 0.06 0.06

2050 0.12 0.12 0.11 0.12

2100 0.23 0.26 0.29 0.35

*Parks that do not have shoreline. These numbers are for the nearest shoreline to the park.

†Parks that are likely to be significantly impacted by changes in land level that could result decreasing relative sea level in the short term followed by increased

relative sea level by the end of the century. Refer to section methods for more information.

‡No data was available for this scenario. Data from an adjacent cell was used in lieu.

§Parks that cover two or more cells. Data were averaged between these parks based on percentage of shoreline in each cell. Adjacent cells were used in

cases where boundaries crossed into null data cells.
C-33

Table C3. IBTrACS data (Knapp et al. 2010) were used to identify the highest recorded storm track to 

have passed within 10 miles of each of the park units. 

Region Park Unit

Highest Recorded Hurricane 

Within 10 mi (16.1 km)

Northeast Region Acadia National Park Hurricane, Saffir-Simpson category 1

Assateague Island National Seashore Hurricane, Saffir-Simpson category 1

Boston Harbor Islands National 

Recreation Area

Hurricane, Saffir-Simpson category 2

Boston National Historical Park Hurricane, Saffir-Simpson category 3

Cape Cod National Seashore Hurricane, Saffir-Simpson category 2

Castle Clinton National Monument Hurricane, Saffir-Simpson category 1

Colonial National Historical Park Tropical storm

Edgar Allen Poe National Historic Site Extratropical storm

Federal Hall National Memorial Hurricane, Saffir-Simpson category 1

Fire Island National Seashore Hurricane, Saffir-Simpson category 2

Fort McHenry National Monument and 

Historic Shrine

Tropical storm

Fort Monroe National Monument Tropical storm

Gateway National Recreation Area Hurricane, Saffir-Simpson category 1

General Grant National Memorial Hurricane, Saffir-Simpson category 1

George Washington Birthplace National 

Monument

Extratropical storm

Governors Island National Monument Hurricane, Saffir-Simpson category 1

Hamilton Grange National Memorial Hurricane, Saffir-Simpson category 1

Harriet Tubman Underground Railroad 

National Monument

Tropical storm

Independence National Historical Park Extratropical storm

New Bedford Whaling National Historical 

Park

Extratropical storm

Petersburg National Battlefield Hurricane, Saffir-Simpson category 2

Roger Williams National Memorial Hurricane, Saffir-Simpson category 3

Sagamore Hill National Historic Site Hurricane, Saffir-Simpson category 2

Saint Croix Island International Historic 

Site

Hurricane, Saffir-Simpson category 2

Salem Maritime National Historic Site Hurricane, Saffir-Simpson category 1
C-34

Table C3 (continued). IBTrACS data (Knapp et al. 2010) were used to identify the highest recorded 

storm track to have passed within 10 miles of each of the park units. 

Region Park Unit

Highest Recorded Hurricane 

Within 10 mi (16.1 km)

Northeast Region

(continued)

Saugus Iron Works National Historic Site Hurricane, Saffir-Simpson category 1

Statue of Liberty National Monument Hurricane, Saffir-Simpson category 1

Thaddeus Kosciuszko National Memorial Extratropical storm

Theodore Roosevelt Birthplace National 

Historic Site

Hurricane, Saffir-Simpson category 1

Southeast Region Big Cypress National Preserve Hurricane, Saffir-Simpson category 4

Biscayne National Park Hurricane, Saffir-Simpson category 4

Buck Island Reef National Monument Hurricane, Saffir-Simpson category 2

Canaveral National Seashore Hurricane, Saffir-Simpson category 2

Cape Hatteras National Seashore Hurricane, Saffir-Simpson category 3

Cape Lookout National Seashore Hurricane, Saffir-Simpson category 3

Castillo De San Marcos National 

Monument

Hurricane, Saffir-Simpson category 3

Charles Pinckney National Historic Site Hurricane, Saffir-Simpson category 4

Christiansted National Historic Site Hurricane, Saffir-Simpson category 4

Cumberland Island National Seashore Hurricane, Saffir-Simpson category 4

De Soto National Memorial Hurricane, Saffir-Simpson category 1

Dry Tortugas National Park Hurricane, Saffir-Simpson category 4

Everglades National Park Hurricane, Saffir-Simpson category 5

Fort Caroline National Memorial Hurricane, Saffir-Simpson category 2

Fort Frederica National Monument Hurricane, Saffir-Simpson category 1

Fort Matanzas National Monument Hurricane, Saffir-Simpson category 1

Fort Pulaski National Monument Hurricane, Saffir-Simpson category 2

Fort Raleigh National Historic Site Hurricane, Saffir-Simpson category 2

Fort Sumter National Monument Hurricane, Saffir-Simpson category 4

Gulf Islands National Seashore Hurricane, Saffir-Simpson category 4

Jean Lafitte National Historical Park and 

Preserve

Hurricane, Saffir-Simpson category 2

Moores Creek National Battlefield Hurricane, Saffir-Simpson category 1
C-35

Table C3 (continued). IBTrACS data (Knapp et al. 2010) were used to identify the highest recorded 

storm track to have passed within 10 miles of each of the park units. 

Region Park Unit

Highest Recorded Hurricane 

Within 10 mi (16.1 km)

Southeast Region 

(continued)

New Orleans Jazz National Historical Park Hurricane, Saffir-Simpson category 2

Salt River Bay National Historic Park and 

Ecological Preserve

Hurricane, Saffir-Simpson category 4

San Juan National Historic Site Hurricane, Saffir-Simpson category 3

Timucuan Ecological and Historic 

Preserve

Hurricane, Saffir-Simpson category 2

Virgin Islands Coral Reef National 

Monument

Hurricane, Saffir-Simpson category 3

Virgin Islands National Park Hurricane, Saffir-Simpson category 3

Wright Brothers National Memorial Hurricane, Saffir-Simpson category 2

National Capital Region Vietnam Veterans Memorial Hurricane, Saffir-Simpson category 2

Washington Monument Hurricane, Saffir-Simpson category 2

Intermountain Region Big Thicket National Preserve Hurricane, Saffir-Simpson category 3

Palo Alto Battlefield National Historical 

Park

No recorded historical storm

Padre Island National Seashore Hurricane, Saffir-Simpson category 4

Pacific West Region American Memorial Park Tropical storm

Cabrillo National Monument Tropical depression

Channel Islands National Park No recorded historical storm

Ebey’s Landing National Historical 

Reserve

No recorded historical storm

Fort Point National Historic Site No recorded historical storm

Fort Vancouver National Historic Site No recorded historical storm

Golden Gate National Recreation Area No recorded historical storm

Haleakala National Park Tropical depression

Hawaii Volcanoes National Park Tropical depression

Kalaupapa National Historical Park Tropical depression

Kaloko-Honokohau National Historical 

Park

Tropical depression

Lewis and Clark National Historical Park No recorded historical storm

National Park of American Samoa No recorded historical storm
C-36

Table C3 (continued). IBTrACS data (Knapp et al. 2010) were used to identify the highest recorded 

storm track to have passed within 10 miles of each of the park units. 

Region Park Unit

Highest Recorded Hurricane 

Within 10 mi (16.1 km)

Pacific West Region

(continued)

Olympic National Park No recorded historical storm

Point Reyes National Seashore No recorded historical storm

Port Chicago Naval Magazine National 

Memorial

No recorded historical storm

Pu’uhonua O Honaunau National 

Historical Park

No recorded historical storm

Puukohola Heiau National Historic Site Tropical depression

Redwood National and State Parks No recorded historical storm

Rosie the Riveter WWII Home Front 

National Historical Park

No recorded historical storm

San Francisco Maritime National 

Historical Park

No recorded historical storm

San Juan Island National Historical Park No recorded historical storm

Santa Monica Mountains National 

Recreation Area

No recorded historical storm

War in the Pacific National Historical Park No recorded historical storm

World War II Valor in the Pacific National 

Monument

Tropical depression

Alaska Region Aniakchak Preserve No recorded historical storm

Bering Land Bridge National Preserve No recorded historical storm

Cape Krusenstern National Monument No recorded historical storm

Glacier Bay National Park No recorded historical storm

Glacier Bay Preserve No recorded historical storm

Katmai National Park No recorded historical storm

Katmai National Preserve No recorded historical storm

Kenai Fjords National Park No recorded historical storm

Klondike Gold Rush National Historical 

Park

No recorded historical storm

Lake Clark National Park No recorded historical storm

Sitka National Historical Park No recorded historical storm

Wrangell - St. Elias National Park No recorded historical storm

Wrangell – St. Elias National Preserve No recorded historical storm
The Department of the Interior protects and manages the nation’s natural resources and cultural heritage; provides scientific 

and other information about those resources; and honors its special responsibilities to American Indians, Alaska Natives, and 

affiliated Island Communities.

NPS 909/145268, May 2018
National Park Service

U.S. Department of the Interior

Natural Resource Stewardship and Science

1201 Oakridge Drive, Suite 150

Fort Collins, CO 80525

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