UNITED STATES

DEPARTMENT OF COMMERCE

Donald L. Evans

Secretary

NATIONAL OCEANIC AND

ATMOSPHERIC ADMINISTRATION

VADM Conrad C. Lautenbacher, Jr.

Under Secretary for Oceans

and Atmosphere/Administrator

Oceanic and Atmospheric

Research Laboratories

Richard D. Rosen

Director

NOAA Technical Memorandum OAR PMEL-124

NOAA TIME SEATTLE TSUNAMI MAPPING PROJECT:

PROCEDURES, DATA SOURCES, AND PRODUCTS

Vasily V. Titov1

Frank I. González2

Harold O. Mofjeld2

Angie J. Venturato1

1

Joint Institute for the Study of the Atmosphere and Ocean (JISAO), Seattle, WA

2

Pacific Marine Environment Laboratory, Seattle, WA

Pacific Marine Environmental Laboratory

Seattle, WA

September 2003
NOTICE

Mention of a commercial company or product does not constitute an endorsement by

NOAA/OAR. Use of information from this publication concerning proprietary products

or the tests of such products for publicity or advertising purposes is not authorized.

Contribution No. 2572 from NOAA/Pacific Marine Environmental Laboratory

For sale by the National Technical Information Service, 5285 Port Royal Road

Springfield, VA 22161

ii
Contents iii

Contents

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

2. Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

3. Tsunami Source . . . . . . . . . . . . . . . . . . . . . . . . . . 2

4. Tsunami Model . . . . . . . . . . . . . . . . . . . . . . . . . . 6

5. Discussion of Modeling Results . . . . . . . . . . . . . . . . . 7

5.1 Offshore Dynamics ........................ 7

5.2 Inundation Details ........................ 7

6. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 10

Appendix A: Bathymetry Data and Computational Grids . . . . 13

Appendix B: Modeling Products . . . . . . . . . . . . . . . . . . . 16

List of Figures

1 Study area of the Seattle Tsunami Mapping Project. Broken line

shows surface signature of the Seattle Fault model. Black rectangle

outlines the area for the high-resolution tsunami inundation modeling. 2

2 Distribution of computed vertical deformations used as a tsunami

source for the inundation study. Contours show deformation of the

earth crust due to rupture of the model Seattle Fault. Resulting

sea-surface deformation is shown color-coded in red (uplift) and blue

(subsidence). White triangles show locations of historical deformation measurements. ............................ 5

3 Snapshots of model tsunami propagation in Elliott Bay. Red color

indicates positive wave amplitudes above Mean High Water (MHW),

blue is negative (below MHW). ..................... 8

4 Distribution of the maximum computed wave heights in Elliott Bay

and runup at Seattle coastlines (in meters above MHW). ....... 9

B1 Vector shoreline of the Seattle Area. . . . . . . . . . . . . . . . . . . 17

B2 Digital Elevation Model (DEM) for modeling Seattle Area inundation

(30 m-resolution). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

B3 DEM for modeling propagation in Puget Sound (90 m-resolution). . 18

B4 Source deformation for the Seattle 30 m DEM. . . . . . . . . . . . . 18

B5 Source deformation for the Puget Sound 90 m DEM. . . . . . . . . . 19

B6 Maximum computed wave heights (measured from Mean High Water)

for each node of the Seattle grid. . . . . . . . . . . . . . . . . . . . . 19

B7 Maximum computed inundation depths (depth of water over land

measured from a topography height) for each node of the Seattle grid. 20

B8 Maximum computed flow velocity (m/s) for each node of the Seattle

grid. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

B9 Zones of maximum inundation for the Seattle grid. . . . . . . . . . . 21

B10 Zones of maximum flow velocity for the Seattle grid. . . . . . . . . . 21

List of Tables

1 Sub-fault parameters (from West to East). ............... 4

2 Comparison of the model source vertical displacements with shoreline

uplift data. ................................ 4

A1 Data sources used for grid development. . . . . . . . . . . . . . . . . 14
iv Contents

A2 Grid summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

B1 Product summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
NOAA TIME Seattle Tsunami Mapping Project: Procedures,

data sources, and products

Vasily V. Titov1, Frank I. Gonz ́alez2, Harold O. Mofjeld2, and Angie J. Venturato1

1. Introduction

This report describes the project of the NOAA Center for Tsunami Mapping

Efforts (TIME) to model and map potential tsunami inundation along the

Puget Sound shores of Seattle, Washington (Fig. 1). The source of the

scenario tsunami is a major (magnitude 7.3) earthquake of the Seattle Fault.

The goal of this work is to provide data for creating tsunami inundation

maps for these areas. The maps are prepared as part of the National Hazard

Mitigation Program to aid local governments in designing evacuation plans

for areas at risk from potentially dangerous tsunamis. The details of the

tsunami generation are extremely important, since the tsunami inundation

area is in close proximity to the tsunami source. Hence the latest scientific

evidence about the Seattle Fault structure and seismicity is employed to

design a tsunami source scenario for this study. We apply a high-resolution

tsunami inundation model to estimate details of the runup on land near the

Seattle shoreline.

2. Background

Recent advancements in geological and paleo-tsunami studies have identified

the Seattle Fault Zone as a substantial seismic and tsunami hazard for the

Seattle Area (Fig. 1). Scientists have collected compelling evidence about

earthquakes and tsunami events originated on the Seattle fault (Gower et al.,

1985; Atwater and Moore, 1992; Johnson et al., 1999; Bourgeois and Johnson,

2001; Brocher et al., 2001; Blakely et al., 2002). Estimates of the repeat

period for a large event on this fault are not well established (probably, in

millennia range). Nevertheless, the proximity to a large metropolitan area

makes the risk from such an event very formidable and warrants thorough

scientific assessment.

It is nearly certain that a tsunami will accompany a large rupture on the

Seattle Fault. The geometry of the fault favors large vertical deformations

of the seabed under Puget Sound, which would result in the displacement of

a large amount of water. The disturbed water mass would then propagate

as tsunami waves. The impact of the tsunami around Puget Sound can

be estimated with numerical modeling. Previous modeling studies of the

Seattle Fault tsunami have focused on reproducing the paleo-evidences of

the tsunami of 1100 years ago. Walters and Takagi (1996) and Holmes

1Joint Institute for the Study of the Atmosphere and Ocean (JISAO), University of

Washington, Box 354235, Seattle, WA 98195-4235 2NOAA/Pacific Marine Environmental Laboratory, 7600 Sand Point Way NE, Seattle,

WA 98115
2 V.V. Titov et al.

Figure 1: Study area of the Seattle Tsunami Mapping Project. Broken line shows

surface signature of the Seattle Fault model. Black rectangle outlines the area for

the high-resolution tsunami inundation modeling.

and Dinkelman (1993) have modeled the propagation of the tsunami around

Puget Sound using a simplified source and a coarse numerical grid. They

identified general patterns of tsunami propagation and offshore amplitudes

of propagating waves around Puget Sound. Koshimura et al. (2002) have

developed a refined model of the same event. They have reproduced much

of the paleo-evidence of the tsunami in Cultus Bay with their inundation

model. The source mechanism of their model is based on the interpretation

of Pratt et al. (1997) of the Seattle Fault geometry.

3. Tsunami Source

The tsunami source for this study assumes wave generation by a rupture of

the Seattle Fault. It is designed as a maximum credible event based on the
TIME: Procedures, data sources, and products 3

scientific evidence about the Fault geometry, seismicity, and field evidence

for co-seismic displacements of the Fault.

Many details of the Seattle Fault are still poorly understood. A steady

stream of new scientific information leads to continuous reassessment of the

Seattle Fault structure and potential (e.g., Pratt et al., 1997; Johnson et al.,

1999; Blakely et al., 2002). The tsunami generation, however, depends only

on the surface manifestation (the amount of vertical offset) of the internal

fault rupture. Therefore, the internal fault geometry, though important,

may not be as vital a constraint for the tsunami model as the vertical deformation evidence. The 900 A.D. earthquake on the Seattle fault produced

uplifts of up to 7 m and subsidence of more than 1 m, based on the shoreline displacement data (e.g., Bucknam et al., 1999; ten Brink et al., 2002).

This earthquake generated a tsunami known from several deposits at West

Point (in Seattle), Cultus Bay (at the south end of Whidbey Island) and the

Snohomish River delta near Everett (Atwater and Moore, 1992; Bourgeois

and Johnson, 2001). Hence, this vertical deformation data (+7 meters at

Restoration Point, +4 meters at Alki Point and at least –1 meter at West

Point) that is known to produce a tsunami from the Seattle Fault is used

here as a main constraint for a credible tsunami source model.

The near-surface structure of the Seattle Fault Zone is fairly well determined from the field evidence, seismic reflection studies, aeromagnetic data,

and gravity anomalies (e.g., Bucknam et al., 1992; Pratt et al., 1997; Brocher

et al., 2001; Calvert and Fisher, 2001; Blakely et al., 2002). Koshimura et al.

(2002) have utilized this surface configuration for their source of the 900 A.D.

tsunami simulation. Our study uses a similar surface signature for the model

source—six sub-faults with surface edges following the northern strand of the

Seattle Fault Zone (Fig. 1).

The data about the internal structure of the Seattle Fault is not as

straightforward to interpret as its surface configuration and is subject to

many different interpretations. Pratt et al. (1997) suggested a wide shallow

dipped fault (20◦) that extends from 16 km deep up to 6 km from the surface,

which breaks to the surface with a steeper (35◦–40◦) narrow strand. This

was the model adopted by Koshimura et al. (2002). Later interpretations

favor steeper and deeper faults extending from depths of 20–28 km to the

surface with dip angles varying from 40◦ to 80◦ (Brocher et al., 2001; Calvert

and Fisher, 2001). Others suggest more complex near surface structure with

secondary faults near the surface (ten Brink et al., 2002). Brocher et al.

(2001) also suggest a link between seismicity of the Seattle Fault and the

Tacoma Fault to the south when one fault may trigger movement on the

other.

Taking into account the uncertainties of the Seattle Fault data and differences in interpretations, we have chosen an unambiguous fault model that

is in general agreement with modern interpretations and, most importantly,

can accommodate the measured vertical displacements of the tsunamigenic

event of 1100 years ago. We assume movement only at the Seattle Fault

Zone in this scenario. Our model has a single fault uniformly dipping at a

60◦ angle down to 17.3 km along all its length. The 60◦ dip angle is within

the uncertainty range of many recent fault models (ten Brink et al., 2002;
4 V.V. Titov et al.

Table 1: Sub-fault parameters (from West to East).

Sub-Fault F1 F2 F3 F4 F5 F6

Length 15.2 km 6.3 km 8.9 km 3.3 km 11.5 km 14.9 km

Width 20 km 20 km 20 km 20 km 20 km 20 km

Strike 87.9◦ 86.6◦ 96◦ 128.8◦ 99.3◦ 81◦

Dip 60◦ 60◦ 60◦ 60◦ 60◦ 60◦

Displacement 1 m 1 m 12 m 11 m 4 m 1 m

Table 2: Comparison of the model source vertical displacements with shoreline

uplift data.

Displacements Model Observations

Alki Point 3.9m 4m

Restoration Point 7.1m 7m

West Point −1.3 m −1 ± 0.5 m

Brocher et al., 2001; Calvert and Fisher, 2001; Blakely et al., 2002). The

lower depth of the fault is also a subject of active debate. Different hypotheses put the low boundary of the fault anywhere from 12 to 28 km deep. Then

again, the deeper part of the fault does not contribute as much to the surface

deformation. Therefore, the depth of the low boundary, though important

for the geophysical understanding of the fault structure, is not significant for

the tsunami generation.

The geophysical data suggest that the Seattle Fault is capable of generating an earthquake of Mw greater than 7, with maximum estimates of

Mw 7.6–7.7 (Pratt et al., 1997; Koshimura et al., 2002). We have chosen a

mid-range of magnitude estimates for the model source Mw = 7.3. Using

this magnitude as a constraint, we have distributed the slip values among

the sub-faults to reproduce vertical displacement estimates of the 900 A.D.

event. The resulting slip distribution and sub-fault’s parameters are listed

in Table 1.

The maximum slip values for our source, though large, are consistent

with data for similar type thrust-earthquakes published elsewhere. A welldocumented thrust fault of the 1999, Mw 7.5, Chi-Chi earthquake in Taiwan,

for example, produced up to a 20 m slip in a small area of the fault (within 5

× 5 km2), which, in turn, generated 11 m vertical offset at the surface above

this asperity (e.g., Zhang et al., 2003).

Table 2 shows comparison of the computed vertical displacements with

the most reliable estimates of the 900 A.D. earthquake offsets at three locations.

Vertical displacements for this model were computed using Okada’s formulation of the elastic deformation approximation (Okada, 1985). Figure 2

shows contours of the computed vertical deformations due to the rupture of

the assumed fault configuration from Table 1. The identical displacement

of the sea surface (color-coded on Fig. 2 as red-uplift, dark blue-subsidence)

above the deformed crust would propagate along Puget Sound as a tsunami

wave, and is used as initial conditions for the tsunami propagation and inundation model.
TIME: Procedures, data sources, and products 5

Figure 2: Distribution of computed vertical deformations used as a tsunami source for the inundation study.

Contours show deformation of the earth crust due to rupture of the model Seattle Fault. Resulting sea-surface

deformation is shown color-coded in red (uplift) and blue (subsidence). White triangles show locations of

historical deformation measurements.
6 V.V. Titov et al.

4. Tsunami Model

The tsunami propagation around Puget Sound and wave inundation on dry

land is simulated with the MOST numerical model (Titov and Gonz ́alez,

1997; Titov, 1997; Titov and Synolakis, 1995). MOST is a finite-difference

numerical algorithm based on the long wave approximation. It solves numerically the non-linear shallow water wave equations written in spherical

coordinates as follows:

ht + (uh)λ + (vh cos φ)φ

R cos φ = 0

ut +

uuλ

R cos φ +

vuφ

R + ghλR cos φ = gdλR cos φ + fv − Cfh |u| u

vt +

uvλ

R cos φ +

vvφ

R + ghφR = gdφR − fu − Cfh |v| v,

where λ is longitude, φ is latitude, h = h(λ, φ, t) + d(λ, φ, t), h(λ, φ, t) is

the amplitude, d(λ, φ, t) is the undisturbed water depth, u(λ, φ, t), v(λ, φ, t)

are the depth-averaged velocities in the longitude and latitude directions,

respectively, g is the gravity acceleration, f is the Coriolis parameter (f =

2ω sin φ) and R is the Earth radius, Cf = gn2/h1/3 (n is the Manning

coefficient). In the MOST model, these equations are solved numerically

using a splitting method similar to that described by Titov (1997).

The MOST model has been extensively tested against various laboratory

experiments (Titov and Synolakis, 1998, 1996) and verified by successfully

reproducing field data for many historical tsunamis (Yeh et al., 1995; Titov

and Synolakis, 1997, 1998; Titov and Gonz ́alez, 1997).

The MOST model was applied for the Seattle simulation without Coriolis

terms. This effect—small even for long-distance tsunami propagation (e.g.,

Kowalik and Whitmore (1991))—is negligible at short distances, such as the

ones in the Puget Sound modeling study. The Manning’s formulation of

the bottom friction is used for the inundation computation with constant

Manning coefficient n = 0.025.

The topography used for the simulation does not include buildings and

other structures, so-called “bald earth” digital elevation model (DEM). These

obstacles may change and decrease inundation estimates, especially for large

flat areas. One way of accounting for that increased dissipation in the longwave model is the use of a greater bottom friction parameter (Fujima, 2001).

However, there are not enough data and scientific studies to choose the

proper friction coefficients to account for large structures. In the absence

of proven scientific estimates, we have chosen to use a standard engineering

value for the Manning parameter corresponding to mildly rough surfaces (n

= 0.025). That approach gives credible conservative estimates of the tsunami

inundation.

To reproduce the correct wave dynamic during the inundation computations, a high-resolution grid is required. The MOST model is designed to

use several nested computational grids to telescope into the high-resolution

inundation area. These high-resolution computations require a high-quality
TIME: Procedures, data sources, and products 7

bathymetry and topography data merged into one computational grid. Appendix A describes the procedure to develop DEMs for the Seattle inundation

modeling. It also lists the sources of the bathymetry and topography used

to create the DEM.

5. Discussion of Modeling Results

5.1 Offshore Dynamics

The Seattle Fault tsunami source creates a sharp bottom dislocation along

the fault surface (Fig. 2). There is an upward displacement to the south

of the Fault and a lesser downward displacement to the north. That dislocation goes across Puget Sound from Bainbridge Island to Alki Beach and

further east crosses both Duwamish Waterways. The corresponding gradient of the water surface forms the initial wave front of the tsunami. The

largest amplitudes are generated at Puget Sound between Bainbridge and

Alki Point. The wave from that portion of the fault propagates directly toward the shores of Magnolia Bluff and into Elliott Bay. The first wave crest

forms a bore with amplitudes above 6 m before reaching the Magnolia Bluff

shore only 2 min 20 sec after generation. Within half a minute after that,

this wave crest reaches all the shores around Elliott Bay. The south shores

of Elliott Bay are not inundated by the first crest, not until a large wave

reflected from the northern coasts reaches Harbor Island about 5 min after

the earthquake (Fig. 3).

5.2 Inundation Details

The model predicts extensive inundation by the tsunami waves in some areas around Elliott Bay. Here, we discuss various aspects of the computed

inundation dynamic and contributing factors that explain these results.

The maximum amplitudes of tsunamis approaching shores of Elliott Bay

are very similar around the Bay, fluctuating around 6 m. Significant differences in the inundation amplitudes and penetration distances are, therefore,

explained mainly by variations of local topography near the shore. Inspection of the topography data reveals that some coastal sites have a very flat

and low profile, with large areas near the shore not more than 5–7 m above

mean high water. One of such areas includes Harbor Island, adjacent port

facilities, and industrial areas that are built on filled land. Another low-lying

area runs north from Smith Cove. The model predicts large inundation distances (up to 1 mile) at both of these locations, but not the largest vertical

amplitudes (Fig. 4).

The highest vertical runup (above 10 m) is computed at steep southwest

bluffs of Magnolia Bluff and second highest at Alki Beach, east of Alki Point

(Fig. 4). In both areas, the inundation distances are very small. Such trends

are predictable and expected. Long waves, like tsunamis, tend to flood the

entire area below its shoreline amplitude. Over flat topography such waves

lose their energy via bottom friction, and the inundation depths then slowly

decrease over long penetration distances.
8 V.V. Titov et al.

 

 

 

Figure 3: Snapshots of model tsunami propagation in Elliott Bay. Red color indicates positive wave amplitudes above Mean High Water (MHW), blue is negative

(below MHW).

Many historical tsunamis demonstrated similar inundation patterns. For

example, the 2001 Peru tsunami penetrated up to 1 mile inland over flat

agricultural fields near Camana (Okal et al., 2002). Steep beaches, on the

other hand, would create nearly perfect reflection, effectively doubling the

amplitudes of incoming long waves. It is also confirmed by field data of

historical events. The 1997 Okushiri tsunami produced the highest runup at

steep cliffs on the west coast of Okushiri Island, which was later reproduced

by the MOST model simulation (Titov and Synolakis, 1997).

Figure B7 shows maximum computed inundation depths that illustrate
TIME: Procedures, data sources, and products 9

Figure 4: Distribution of the maximum computed wave heights in Elliott Bay and

runup at Seattle coastlines (in meters above MHW).

those inundation patterns. It demonstrates the decrease of flow depths away

from a shoreline for inundation at large flat areas around Harbor Island and

near Smith Cove, while higher inundation amplitudes are computed at steep

shores with short inundation distances at SW Magnolia Bluff and at eastern

Alki Beach. To present the internal structure of computed inundation, we

have decided to use zones of inundation based on the computed flow depth:

low, medium, and high inundation (Fig. B9). The zoned inundation map

provides a more complete and informative representation of the flooding

than just a single maximum inundation line.

These modeling results are intended for development of the tsunami in-
10 V.V. Titov et al.

undation maps for the Seattle Area. The numerical data from the described

simulation is provided to Washington State officials for development of the

inundation maps and additional products. Appendix B lists all modeling

products prepared as a result of this study.

6. Acknowledgments

This research is funded by the National Tsunami Hazard Mitigation Program

via a grant from the Washington State Emergency Management Division.

We thank George Crawford, Timothy Walsh, Craig Weaver and many other

researchers for helpful discussions regarding Seattle Fault source.

This publication is partially funded by the Joint Institute for the Study of

the Atmosphere and Ocean (JISAO) under NOAA Cooperative Agreement

No. NA67RJ0155, Contribution # 1006.

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(2002): Tidal datum distributions in Puget Sound, Washington, based on

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TIME: Procedures, data sources, and products 13

Appendix A: Bathymetry Data and

Computational Grids

Procedure

The TIME Center has developed data grids for the Seattle inundation mapping project using the following five-step process:

 Data Collection

 Data Assessment

 Grid Computation

 Grid Assessment

 Product Delivery

The best available bathymetric and topographic data were obtained from

government agencies. These sources are listed in the next section. The

data were reformatted and then analyzed for quality using ESRI GIS software. Datasets were converted to the Universal Transverse Mercator Zone

10 projection and the North American Datum of 1983. The data were then

corrected to a vertical datum of Mean High Water using tidal data obtained

over a 19-year period (1960–1978) from the Seattle National Ocean Service

water level station (station number 944-7130). Bathymetric data was corrected from Mean Lower Low Water, and topographic data was corrected

from National Geodetic Vertical Datum of 1929. The mean values were calculated by the National Ocean Service using the 1960–1978 tidal epoch and

were assumed constant throughout the Seattle model region. This approximation is accurate to within ±0.05 m along the Seattle shoreline (Mofjeld

et al., 2002).

A coastline file was generated based on governmental data sources and

local knowledge of the Seattle Area. Some piers with open pile foundations

were eliminated from the coastline data for inundation modeling purposes.

Tsunami waves can freely propagate under these piled piers, therefore the

inundation is better modeled without those piers as part of the reflective

shoreline.

A combined bathymetric and topographic data grid was then generated

using ArcInfo. Various datasets were combined using Triangulated Irregular

Network modeling. The results were converted into a rectangular grid of

30-meter resolution. Two grids were generated from the original 30-meter

grid: a subset of the 30-meter grid focusing on Elliott Bay and a 90-meter

grid using a resampling technique.

The computed grid was analyzed for quality. Comparisons were made

between the original datasets and the grid. Datums were verified and point

errors were removed.

The grids were then converted into geographic coordinates for use by the

MOST numerical model. The grids being distributed to Division of Geology

and Earth Resources are in the State Plane Coordinate System of 1927, Zone

5626 with the North American Datum of 1927.
14 V.V. Titov et al.

Table A1: Data sources used for grid development.

Media Source Media Data Description

National Ocean Service

(NOS)

Digital Elevation

Model

30-meter NOS

bathymetry digital

elevation model

Bathymetric data obtained

from 1934–1982 by NOS

National Geophysical

Data Center (NGDC)

CD-ROM (GEODAS

Version 4.1)

NOS Hydrographic

Surveys

Bathymetric data from 1998

NOS hydrographic survey

USGS Open File Report

OF01-266

ArcInfo Grid 4-meter NOS bathymetry

digital elevation model

Bathymetric data from 2001

NOS hydrographic survey

University of Washington

PRISM Project

ArcInfo Grid 10-meter topography

digital elevation model

Topographic data obtained

from the U.S. Geological

Survey

City of Seattle Arcview Point

Shapefiles

2-foot contour

topography of Seattle

Topographic data obtained

in 1993 from aerial

photogrammetry

Data Sources

The data sources for the grids are described in Table A1. The resolution

of each data source varied from approximately 1–30 meters. Many sources

were in different formats, which may lead to a small conversion error. The

vertical accuracy of the data is based on the root mean square error; approximately 5% of depth for bathymetry and one-half of the contour interval for

topography.

The data sources used for the DEMs are credited to the following groups:

 National Oceanic and Atmospheric Administration, National Geodetic

Database Centers. Hydrographic Surveys, GEODAS Version 4.1 Software. Boulder, Colorado.

Website reference: http://www.ngdc.noaa.gov/mgg/bathymetry/

relief.html.

 National Oceanic and Atmospheric Administration, National Ocean

Service. NOS Estuarine Bathymetry. Silver Spring, Maryland.

Website reference: http://mapfinder.nos.noaa.gov/.

 U.S. Geological Society, Western Region Geology. Open File Report

OF01-266. San Francisco, California.

Website reference: http://geopubs.wr.usgs.gov/open-file/of01-266/.

 Washington State Geospatial Data Archive, University of Washington. U.S. Geological Survey 10-meter Digital Elevation Model. Seattle, Washington.

Website reference: http://duff.geology.washington.edu/data/raster/

tenmeter/.
TIME: Procedures, data sources, and products 15

Table A2: Grid summary.

Region Name Resolution Extents (SW and NE corners)

Puget Sound seattle90 90 meters SW: −122.752, 47.035

NE: −122.175, 48.124

Elliott Bay seattle30 30 meters SW: −122.454, 47.549

NE: −122.321, 47.668

 City of Seattle, Seattle Public Utilities. City of Seattle Topography.

Seattle, Washington.

Website reference: http://www.cityofseattle.net/util/.

 National Oceanic and Atmospheric Administration, Center for Operational Oceanographic Products and Services, Water Level Station

Information for Kodiak Island, Alaska. Silver Spring, Maryland.

Website reference: http://www.co-ops.nos.noaa.gov/.

 Information about ESRI GIS software can be found on the Internet at

http://www.esri.com/.

Products

Two grids are being delivered to the Division of Geology and Earth Resources. Each grid is described in Table A2. The grids are in ArcInfo

exchange format and have the following parameters:

 Grid Generation Software: ArcInfo, Version 8.0.2

 Grid Algorithm: Triangulated Irregular Network

 Horizontal Datum: North American Datum of 1927

 Vertical Datum: Mean High Water

 Projection: State Plane Coordinate System of 1927, Zone 5626

 Units: feet

 Z Units: meters

 Grid accuracy is based on the level of detail of the source and the grid

interval used to sample the source.
16 V.V. Titov et al.

Appendix B: Modeling Products

Three vector files, nine raster grids, and an animation are included on a

CD-ROM with this report.

Each product is summarized in Table B1. All files are in the ESRI

ArcView 3.2 format and have the following parameters as requested by the

Division of Geology and Earth Resources:

 Projection: State Plane Coordinate System

 Zone: 5626 (Washington South)

 XY Units: feet

 Z Units: meters (meters/second for speeds)

 Horizontal Datum: North American Datum of 1927

 Vertical Datum: Mean High Water

Each file has an associated gif image and metadata report. The vector

files and raster grids are displayed in an ArcView 3.2 project file for easy

access and distribution. The animation is in QuickTime format. A NOAA

Technical Memorandum and model output will be distributed at a later date.

Table B1: Product summary.

Item Name Filename Type Image Metadata Resolution (m)

0 (a) Model Output seattle.qt Quick-Time

(b) Animation

(c) Documentation

1 Shoreline shore orig vector shore orig.gif shore orig meta various

2 Pierless Shoreline shoreline vector shoreline.gif shoreline meta various

3 DEM (30 m res.) seattle30 raster seattle30.gif seattle30 meta 30

4 DEM (90 m res.) seattle90 raster seattle90.gif seattle90 meta 90

5 DEM with Source Deformation def30 raster def30.gif def30 meta 30

(30 m res.)

6 DEM with Source Deformation def90 raster def90.gif def90 meta 90

(90 m res.)

7 Source Deformation (30 m res.) src30 raster src30.gif src30 meta 30

8 Source Deformation (90 m res.) src90 raster src90.gif src90 meta 90

9 Maximum Wave Heights maxh raster maxh.gif maxh meta 30

10 Maximum Inundation Depths maxd raster maxd.gif maxd meta 30

11 Maximum Current Speeds maxv raster maxv.gif maxv meta 30

12 Maximum Inundation Depth Lines inundation vector inundation.gif inundation meta 30

13 Maximum Inundation Depth Zones maxd raster maxd zones.gif maxd meta 30

14 Maximum Current Speed Zones maxv raster maxh zones.gif maxv meta 30
TIME: Procedures, data sources, and products 17

Figure B1: Vector shoreline of the Seattle Area.

Figure B2: Digital Elevation Model (DEM) for modeling Seattle Area inundation (30 m-resolution).
18 V.V. Titov et al.

Figure B3: DEM for modeling propagation in Puget Sound (90 m-resolution).

Figure B4: Source deformation for the Seattle 30 m DEM.
TIME: Procedures, data sources, and products 19

Figure B5: Source deformation for the Puget Sound 90 m DEM.

Figure B6: Maximum computed wave heights (measured from Mean High Water) for each node of the

Seattle grid.
20 V.V. Titov et al.

Figure B7: Maximum computed inundation depths (depth of water over land measured from a topography

height) for each node of the Seattle grid.

Figure B8: Maximum computed flow velocity (m/s) for each node of the Seattle grid.
TIME: Procedures, data sources, and products 21

Figure B9: Zones of maximum inundation for the Seattle grid.

Figure B10: Zones of maximum flow velocity for the Seattle grid.