NOAA Technical Memorandum NOS CS 17

VDATUM FOR THE COASTAL WATERS OF 

SOUTHERN CALIFORNIA: TIDAL DATUMS 

AND SEA SURFACE TOPOGRAPHY 

Silver Spring, Maryland 

December 2009 

noaa National Oceanic and Atmospheric Administration 

U.S. DEPARTMENT OF COMMERCE 

National Ocean Service 

Coast Survey Development Laboratory 
ii 

Office of Coast Survey 

National Ocean Service 

National Oceanic and Atmospheric Administration 

U.S. Department of Commerce

The Office of Coast Survey (OCS) is the Nation’s only official chartmaker. As the 

oldest United States scientific organization, dating from 1807, this office has a 

long history. Today it promotes safe navigation by managing the National 

Oceanic and Atmospheric Administration’s (NOAA) nautical chart and 

oceanographic data collection and information programs. 

There are four components of OCS: 

The Coast Survey Development Laboratory develops new and efficient 

techniques to accomplish Coast Survey missions and to produce new and 

improved products and services for the maritime community and other 

coastal users. 

The Marine Chart Division acquires marine navigational data to construct 

and maintain nautical charts, Coast Pilots, and related marine products for 

the United States. 

The Hydrographic Surveys Division directs programs for ship and shorebased hydrographic survey units and conducts general hydrographic 

survey operations. 

The Navigational Services Division is the focal point for Coast Survey 

customer service activities, concentrating predominately on charting 

issues, fast-response hydrographic surveys, and Coast Pilot updates. 
iii 

NOAA Technical Memorandum NOS CS 17 

VDATUM FOR THE COASTAL WATERS OF 

SOUTHERN CALIFORNIA: TIDAL DATUMS 

AND SEA SURFACE TOPOGRAPHY 

Zizang Yang, Edward P. Myers, Emily Dhingra, and Adeline Wong 

Office of Coast Survey, Coast Survey Development Lab, Silver Spring, 

MD 

Stephen A. White 

National Geodetic Survey, Silver Spring, MD 

December 2009

noaa National Oceanic and Atmospheric Administration 

U. S. DEPARTMENT National Oceanic and National Ocean Service 

OF COMMERCE Atmospheric Administration John H. Dunnigan 

Gary Locke Dr. Jane Lubchenco Assistant Administrator 

Secretary Under Secretary of 

 Commerce for Oceans and 

 Atmosphere 

Office of Coast Survey Coast Survey Development 

Captain Steven R. Barnum, NOAA Laboratory 

Director Mary Erickson, Chief 
iv 

NOTICE 

Mention of a commercial company or product does not constitute an 

endorsement by NOAA. Use for publicity or advertising purposes of 

information from this publication concerning proprietary products or 

the tests of such products is not authorized.

 
v 

TABLE OF CONTENTS

LIST OF FIGURES ....................................................................................................................... vi 

LIST OF TABLES ........................................................................................................................ vii 

ABSTRACT ................................................................................................................................... ix 

1. INTRODUCTION .......................................................................................................................1 

2. COASTLINE, BATHYMETRY, AND WATER LEVEL DATA ..............................................3 

2.1. Digital Coastline ...........................................................................................................3 

 2.2. Bathymetric Data ..........................................................................................................3 

2.3. Tidal Datum Data ..........................................................................................................6 

3. TIDAL DATUM SIMILATION ..................................................................................................7 

3.1. Hydrodynamic Model ...................................................................................................7 

 3.2. Model Grid ....................................................................................................................7 

3.3. Bathymetry on Model Grid .........................................................................................11 

3.4. Model Parameters Setup .............................................................................................12 

3.5. Tidal Datum Computation and Results .......................................................................13 

3.6. Verifications and Error Corrections ............................................................................15 

4. CREATION AND POPULATION OF THE MARINE GRID .................................................27 

4.1. Creation of VDatum Marine Grid ...............................................................................27 

 4.2. Population of VDatum Grid with Tidal Datums .........................................................29 

5. TOPOGRAPHY OF THE SEA SURFACE ..............................................................................31 

5.1. Creation of VDatum Marine Grid ...............................................................................32 

 5.2. Quality Control ...........................................................................................................35 

6. SUMMARY ...............................................................................................................................37 

ACKNOWLEDGMENTS .............................................................................................................37

REFERENCES ..............................................................................................................................37 

APPENDIX A. HORIZONTAL AND VERTICAL ACCURACY STANDARDS FOR 

NOAA BATHYMETRY SURVEY ....................................................................41 

APPENDIX B. WATER LEVEL STATION DATA ....................................................................43 

APPENDIX C. CORRECTED TIDAL DATUMS ON MARINE GERID ...................................45 

APPENDIX D. TIDAL GAUGE AND BENCH MARKS DATA USED TO CREATE 

THE TSS ..............................................................................................................49 

APPENDIX E. DERIVED NAVD 88-TO-LMSL VALUES ........................................................51 

APPENDIX F. QA/QC DELTAS AT STATIONS FOR TSS GRIDS .........................................53 

APPENDIX G. COMPARISONS OF DERIVED TSS WITH OBSERVATIONS AT 

TIDAL GAUGE AND TIDAL BENCH MARKS ..............................................57 
vi 

LIST OF FIGURES 

Figure 1. Map of the Southern California, and adjacent coastal water areas. Black lines 

illustrate MHW coastal lines. Green line marks locations at a distance of 25-

nautical miles offshore.. ...................................................................................................2 

Figure 2. Spatial coverage of NOS sounding surveys .....................................................................4 

Figure 3. ENC bathymetry data used in the present study ...............................................................4 

Figure 4. Digitized RNC bathymetry ...............................................................................................5 

Figure 5. Coastal Relief Model for Mexico territory .......................................................................5 

Figure 6. Finite element grid for the entire model domain ..............................................................8 

Figure 7. Close-up view of the hydrodynamic model grid for areas (a) surrounding the 

Santa Barbara and adjacent islands, and (b) between San Diego and Santa 

Monica ............................................................................................................................9 

Figure 8. Model grid bathymetry relative to MZ. Color bar is in meters Monica .........................12 

 

Figure 9. Model derived tidal datum fields, (a) MHHW, b) MHW, (c) MLW, and 

(d) MLLW ......................................................................................................................13 

Figure 10. Comparisons of the modeled (a) MHHW, (b) MHW, (c) MLW, and 

(d) MLLW datums against observations ......................................................................16 

Figure 11. Color-coded model-data differences at each observational station ..............................17 

Figure 12. Map of the Southern California model domain (red line) and bounding 

polygons of the Central California VDatum region. Blue dots (transect AA’) 

represent the southern CA model grid nodes adjacent to the southern border of 

the central CA VDatum ...............................................................................................18 

Figure 13. Comparisons of tidal datums at discrete locations (blue symbols along transect 

AA’ in Figure 11), (a) MHHW, (b) MHW, (c) MLW, and (d) MLLW at 

locations (black circles in Figure 11). The abscissa, Location Index, is counted 

from A to A’ (Figure 12). ............................................................................................19 

Figure 14. TCARI interpolated tidal datum error fields on the unstructured grid, (a) 

MHHW, (b) MHW, (c) MLW, and (d) MLLW. Color bars are in the unit of 

meters ...........................................................................................................................21 
vii 

Figure 15. Corrected tidal datum fields on the unstructured grid, (a) MHHW, (b) MHW, 

(c) MLW, (d) MLLW, (e) MTL, and (f) DTL. Color bars are in the unit of 

meters ...........................................................................................................................23 

Figure 16. The marine grid bounding polygon (blue line). The green line marks locations 

25-nautical miles offshore. The red line illustrates the open boundary of the 

hydrodynamic model ...................................................................................................28 

Figure 17. Location of tidal bench marks and tide stations used to compute the Southern 

California Vicinity VDatum TSS grids ........................................................................31 

Figure 18. The Southern California TSS field based on NAVD88 realized through 

GEOID99. ....................................................................................................................33

Figure 19. The Southern California TSS field based on NAVD88 realized through 

GEOID03. ....................................................................................................................34

LIST OF TABLES 

Table 1. The average differences of MHHW, MHW, MLW, and MLLW across 

boundaries of different VDatum regimes. .......................................................................19 

Table 2. Marine grids parameters ..................................................................................................27 

 
viii 

 
ix 

ABSTRACT 

An application of VDatum, a vertical datum transformation software tool, is developed 

for the southern California coastal area and adjacent waters. VDatum allows users to 

convert vertical elevation/depth data between various tidal, orthometric, and ellipsoidbased 3D reference systems. 

 

The tidal datums fields for this VDatum application were derived from tidal simulations 

using the finite element model ADCIRC. An unstructured triangular grid consisting of 

181,420 nodes and 349,351 cells was created for this region. The model was forced with 

nine tidal constituents (K1, P1, O1, Q1, M2, S2, N2, and K2) and run for 40 days. Modelsimulated water level time series were utilized to derive various tidal datum fields, 

including mean lower low water (MLLW), mean low water (MLW), mean high water 

(MHW), and mean higher high water (MHHW). Model results were validated through 

comparison with observations from 35 water level stations maintained by the NOAA’s 

Center for Operational Oceanographic Products and Services (CO-OPS). Discrepancies 

between model results and observational datums were attributed to model errors and 

interpolated over the whole model domain using TCARI (Tidal Constituent And Residual 

Interpolation), a spatial interpolation tool based on solution of Laplace’s equation. These 

spatially varying error fields were added to the original model results to to derive 

corrected tidal datum fields on the unstructured grid. These final tidal datum fields were 

interpolated onto regularly structured marine grid to be used by the VDatum software. 

The Topography of Sea Surface (TSS), defined as the elevation of NAVD88 relative to 

local mean sea level (LMSL), was developed based on interpolation of bench mark data 

maintained by CO-OPS and the National Geodetic Survey (NGS). The NAVD88-toLMSL values were derived either by fitting tidal model results to tidal bench marks 

leveled in NAVD88 or by calculating orthometric-to-tidal datum relationships at NOAA 

tidal gauges. Results by both methodologies were coupled to create the final TSS grids 

using spatial interpolation. 

Key Words: tides, tidal datums, southern California, ADCIRC, mean sea level, 

bathymetry, coastline, spatial interpolation, marine grid, North American Vertical Datum 

of 1988. 
x 
1 

1. INTRODUCTION 

NOAA’s NOS is developing a software tool called VDatum to transform elevation data 

among approximately 30 vertical datums (Milbert, 2002; Parker, 2002; Myers et al. 

2005). Once VDatum has been established for a region, data sets referenced to different 

vertical datums can be integrated through transformations to a common vertical datum 

(Parker et al., 2003). VDatum allows all bathymetric and topographic data to be 

integrated in this manner through its inherent geoidal, ellipsoidal, and tidal relationships. 

To be applicable over coastal waters, VDatum requires spatially-varying fields of the 

tidal datums and the Topography of Sea Surface (TSS). The former includes datums such 

as MHHW, MHW, MLW, MLLW, Mean Tidal Level (MTL), and Diurnal Tidal Level 

(DTL) defined relative to Mean Sea Level (MSL). The latter refers to the elevation of the 

North American Vertical Datum of 1988 (NAVD88) relative to MSL. 

This report describes the development of VDatum for an area encompassing the southern 

California coastal waters between the U.S.-Mexico border in the south and Morro Bay, 

CA in the north. Figure 1 displays a map of the area. In the figure, the black line 

represents the MHW coastline and the green line denotes the 25-nm offshore 

demarcation. Tidal datums for VDatum are generally developed for water areas between 

the coastline and the 25-nm offshore limit. 

Creation of VDatum begins with simulating tides using a hydrodynamic model. Water 

level time series at each model node were recorded and used to compute tidal datums. 

The tidal datums were then verified through comparisons with observational data, and 

error corrections were made based on model-data differences. Regularly structured 

VDatum marine grids were created and populated with the corrected tidal datums. 

Finally, for the same marine grids, the NAVD88-to-LMSL field was derived by either 

fitting tidal model results to tidal bench marks leveled in NAVD88 or calculating 

orthometric-to-tidal datum relationships at NOAA water level stations. 

This technical report is organized as follows: After an introduction in Section 1, Section 2 

discusses data input needed for the tidal simulation and verification of the model results. 

Such data inputs include the digital coastline, bathymetry, and tidal datums derived from 

observational data. Section 3 details the tidal datum simulation procedures, including a 

description of the tidal hydrodynamic model, its setup, result validation, and error 

corrections. Section 4 discusses creation of the regularly structured marine grid required 

for the VDatum software tool and its population with error-corrected model datums. In 

Section 5, the creation of TSS is described. Finally, a summary is given in Section 6. 

 
2 

Figure 1. Map of the southern California coast and adjacent water areas. The grey areas 

represent land/islands and the surrounding black lines illustrate the MHW 

shoreline. The green line marks locations 25-nautical miles offshore. The blue 

line south of San Diego denotes the U.S. and Mexico border. The red line 

illustrates the open ocean boundary of the hydrodynamic model. 

San 

Clemente 

San Miguel 

Island 

Pacific 

Ocean 

San 

 Diego 

Morro 

Bay 

Santa Rosa

Island

Santa Cruz 

Island

Santa 

Catalina 

San Nicolas 

Island 

Santa Barbara

United 

States 

Mexico
3 

2. COASTLINE, BATHYMETRIC, AND WATER LEVEL DATA 

VDatum requires an accurate representation of the spatial distribution of tidal datum 

fields (Milbert and Hess, 2001). To achieve this, VDatum applications are developed 

using a combination of observational data, hydrodynamic models, and spatial 

interpolation techniques (Myers, 2001; Spargo and Woolard, 2005). For this VDatum 

application in Southern California, a tide model was first set up to compute spatially 

varying tidal datums. The modeled tidal datums were next compared with those derived 

from CO-OPS observational data. Finally, spatial interpolation techniques were used to 

create a correction field to be applied to the model results to derive a corrected field of 

tidal datums that are consistent with the observations. 

For the tidal simulations, coastline data are required for delineating land-water 

boundaries so as to define hydrodynamic model domains. In addition, bathymetric data 

are needed to provide the model grid bathymetry. Numerical model results may not 

exactly match CO-OPS observations, and therefore observational data are needed to 

verify and correct the model results. 

2.1. Digital Coastline 

For VDatum, the mean high water shoreline is used as the coastline to delineate the landwater boundaries (Parker, 2002). The shoreline data used in the present study were 

mainly based on the Extracted Vector Shoreline (EVS) dataset available from the NOS 

Office of Coast Survey (OCS). However, compared to NOAA nautical chart MHW 

shorelines, this dataset had errors in certain nearshore marshland areas. The erroneous 

MHW depictions were corrected using computer-aided techniques, so as to reach a close 

match with those illustrated on NOAA’s Raster Navigational Charts (RNC). This was 

implemented via a commercial software package called Surface-Water Modeling System 

(SMS). Using SMS, geo-referenced NRC and the EVS data were contrasted visually. 

Wherever the two did not match, the EVS was judged to be incorrect and replaced by the 

corresponding chart coastline. In Figure 1, the black line illustrates the final corrected 

coastline. 

2.2. Bathymetric Data 

Bathymetric data used in this study were from three sources: (1) NOS soundings, (2) the 

NOAA Electronic Navigational Charts (ENCs) bathymetry, (3) manually digitized RNCs 

bathymetry, and (4) Coastal Relief model bathymetry. The soundings were from the 

NOS/OCS hydrographic database maintained at the National Geophysical Data Center 

(NGDC). The latter two were based on the NOAA ENCs and RNCs, respectively. Figure 

2 displays spatial coverage of the soundings. Figure 3 and 4 respectively mark the 

locations of the ENC and RNC data points employed in the present study. Figure 5 shows 

the locations of the CRM bathymetry. Note that only those near the Mexico territory are 

used, due to the unavailability of any other data sets. 

The NOS sounding data include surveys between 1930 and 2000. Table A.1 in Appendix 

A gives details on their horizontal and vertical accuracy standards. They were referenced 
4 

to either MLW or MLLW, depending on the years of data collection. The ENC and RNC 

bathymetry were treated as being relative to MLW. It is noted that bathymetry data 

referenced to different tidal datums were adjusted to a common reference level before 

being merged for creating the model grid bathymetry. Details on the adjustment 

procedures are given in Section 3.3. 

Figure 2. Spatial coverage of sounding data 

Figure 3. ENC bathymetry data used in the present study 

 
5 

Figure 4. Digitized RNC bathymetry (It’s mostly just in San Diego, but there are a 

couple of points along the coast where the data helped fill in some gaps)

Figure 5. Coastal Relief Model for Mexico’s coastal waters. 
6 

The NOS soundings possess a higher spatial distribution density than the ENC data. In 

some areas, the two are commonly available. However, neither of them provides 

complete coverage for the whole study area. Hence, they were blended for improved 

regional coverage. It is noted that even the merged data set left certain nearshore regions 

uncovered. NOAA nautical chart bathymetry was then manually digitized to compensate 

for this missing coverage. Since both the ENC and manually digitized bathymetries were 

grounded in nautical chart data, they were merged to form one data set and hereafter 

referred to as the ENC bathymetry without differentiation. 

2.3. Tidal Datum Data 

Tidal datum elevations from CO-OPS water level stations were used to verify and correct 

model results (Hess and Spargo, 2005). Many stations are located within either 

embayments or near obstructions not represented in the present model grid (Section 3.2), 

or at upper-reaches of riverine areas where datums exhibit strong seasonal variability. 

Observations at these stations were deemed to be unsuitable for validating model results 

and discarded. The observational data correspond to either the present National Tidal 

Datum Epoch (NTDE 1983-2001) or the older one (NTDE 1960-1979), and there were 

also some historical observations for which the epoch was not documented. It is noted 

that at some stations, datums are available for both the present epoch and others. In this 

case, only those with the most recent epoch are used. This resulted in 38 stations actually 

used for model validations. Tables B.1 and B.2 in Appendix B list the station and tidal 

datum information. 

 
7 

3. TIDAL DATUM SIMULATION 

3.1. Hydrodynamic Model 

The ADvanced CIRCulation (ADCIRC) model (Luettich et al., 1992; Westerink and 

Luettich, 1993; Luettich and Westerink, 2003) was employed to simulate water level time 

histories and derive tidal harmonic constant fields. The ADCIRC model is an 

unstructured grid, hydrodynamic circulation model. It solves the shallow water equations 

and has been used for modeling tides in various ocean, coastal and estuarine 

environments (Luettich et al., 1999; Mukai et al., 2002; Myers 2005). The ADCIRC 

model provides a variety of options for users to specify various aspects of tidal dynamics 

and execution modes. For instance, the model may be used in either 2- or 3-dimensonal 

modes, serial or parallel execution dependent on machine infrastructures, linear or 

quadratic bottom friction formulations with constant or variable friction coefficients, etc. 

More details on the model setup including the model grid generation, bathymetry 

specification, and parameter selections are addressed in following sections. 

3.2. Model Grid 

The model domain encompasses the southern portion of the California coastal waters 

between Morro Bay in the north and the U.S.-Mexico border in the south (Figure 4). The 

domain extends from the coastline toward an area beyond the shelf break. A highresolution, unstructured, triangular grid of 181,420 nodes and 349,351 cells was created 

to represent the area up to the MHW shoreline. The grid spacing ranges from around 20 

m nearshore to 44 km in the offshore regions. In general, finer grids were created for 

nearshore areas compared to those in deep waters, so as to accurately resolve fine 

coastline features and the bathymetric-dependent variability of tidal wavelengths. Figures 

5(a) and (b) show close-up views of the grid in the areas (a) surrounding Santa Barbara 

and adjacent islands, and (b) along the coast between San Diego and Santa Monica. The 

grid resolves various coastal embayments and inlets. 
8 

Figure 6. Finite element grid for the entire model domain. Red line represents the model 

open ocean boundary. 
9 

Figure 7. Close-up view of the hydrodynamic model grid for areas (a) surrounding Santa 

Barbara and adjacent islands, and (b) between San Diego and Santa Monica. 

 

(a) 
10 

Figure 7. (Continued) 

(b) 
11 

3.3. Bathymetry on Model Grid 

The model grid was populated separately with the four bathymetric datasets (Section 2.2) 

using a cluster averaging approach (Yang et al., 2004) to form four bathymetry grids, 

corresponding to (1) ENC data, (2) NOS sounding data, (3) digitized RNC data, and (4) 

CRM data, respectively. Owing to the limited spatial coverage of each data set, each of 

the four grids left numerous unpopulated nodes. Meanwhile, the nodes with valid 

bathymetry vary from grid to grid. 

The four grids were then merged for an improved coverage. First, the ENC grid was 

treated as a baseline grid. Next, the NOS grid was used to assign values to the baseline 

grid nodes with null bathymetry. Digitized RNC grid was then added to the remaining 

null-value nodes. Finally, the CRM grid was employed. After the merging, there were 

still 15,720 unpopulated nodes (about 8.5% of the domain). They were then filled in by 

interpolating or extrapolating from surrounding nodes with valid bathymetry depths. 

The merged grid was referenced to MLLW. The hydrodynamic model requires 

bathymetry referenced to a model zero (MZ), which represents a constant geopotential 

surface. Prior to any initial model rerun, the difference between MZ and MLLW is 

unknown. For the initial guess, the bathymetry was adjusted to MSL, which was 

considered to be equal to MZ for the first run, by adding 0.84 meters to every node. This 

number was the average difference between MLLW and MSL at 38 stations in the region.

The model was run in an iterative fashion, such that the model results were used to adjust 

the original grid with bathymetry data referenced to MLLW to a new depths referenced to 

MZ. After 3 model runs, the results were “converged” in the sense that the results did not 

change from run to run. Figure 8 displays bathymetry used for the final model run. 
12 

Figure 8. Model grid bathymetry relative to MZ. Color bar is in meters. 

3.4. Model Parameters Setup 

In the present study, model parameters were set up to solve the shallow water equations 

in Two-Dimensional Depth-Integrated (2DDI) mode with finite amplitude and 

convection terms. Lateral viscosity was set as a constant, 5.0 m s-2, throughout the model 

domain. A quadratic friction scheme with a constant coefficient of Cf=0.0025 was 

specified to calculate bottom friction. 

The eight most significant astronomical tidal constituents (M2, S2, N2, K2, K1, P1, and O1) 

in the area were chosen as tidal forcings on the model’s open boundary. Corresponding 

harmonic constants were interpolated based on a tidal database covering the eastern north 

Pacific ocean (ENPAC2003) (Spargo, 2003). A time step of 4.0s was used to ensure the 

model’s numerical stability. The simulation covered a period of over 40 days. First, the 

model was ramped up for 5 days with a hyperbolic tangent function. Between days 5.5-

40, time series of the modeled water levels were save at 6 minute intervals at each node 

in the grid. 

The parallel version of ADCIRC model was adopted and the model run was conducted on 

128-processors of the JET computer at Earth Research System Laboratory. 
13 

3.5. Tidal Datum Computation and Results

Water level time series from the final ADCIRC simulation were recorded at 6-minute 

intervals at each grid node. They were passed into the FORTRAN program lv5.f to 

calculate the following tidal datum fields: MSL, MHHW, MHW, MLW, and MLLW. 

The computed datums were referenced to MZ. The latter four were then adjusted to be 

referenced to the modeled MSL field. Henceforth, references to each of the tidal datums 

shall imply this adjusted value relative to MSL. Note that MTL is defined as the algebraic 

average of MHW and MLW, and DTL is the algebraic average of MHHW and MLLW. 

The two fields were not computed until error-corrected MHHW, MHW, MLW, and 

MLLW fields were obtained (Section 4.2). 

Figures 9(a)-(d) display the model derived tidal datum fields for MHHW, MHW, MLW, 

and MLLW, respectively relative to MSL. The four fields exhibit a similar spatial pattern. 

Magnitudes of tidal datums are amplified as tides approach shorelines. For instance, 

MHHW starts from about 0.75 m along the shelf break and reaches up to about 0.8-0.9 m 

near the Southern California coasts. In general, tidal datum magnitudes in the southern 

portion of the domain appear greater than those in the northern portion. The MHHW 

reaches around 0.87 m near the Santa Monica coast as compared to a much smaller value 

of about 0.75 m at Morro Bay. 

 

Figure 9. Model derived tidal datum fields, (a) MHHW, b) MHW, (c) MLW, and (d) 

MLLW. The Color Bars are in meters. 

(a) 
14 

Figure 9. (Continued) 

 

(b) 

(c) 
15 

Figure 9. (Continued) 

3.6. Verifications and Error Corrections 

3.6.1. Comparisons with Observations 

To verify model results, simulated tidal datums were compared with those from 38 NOS 

water level stations (Appendix B). Figures 10(a)-(d) display model-data contrasts for 

MHHW, MHW, MLW, and MLLW, respectively. In general, these exhibit good modeldata agreement. Over the 38 stations, magnitudes of the model-data differences are 

averaged to be 2.8 cm, 1.3 cm, 1.9 cm, and 4.7 cm for MHHW, MHW, MLW, and 

MLLW, respectively. The model-data correlation coefficients demonstrate a constant 

0.99 for all four tidal datums. 

For each individual station, averaged magnitudes (|Avg|) of model-data differences over 

the four datums are examined. Figure 11 illustrates |Avg|’s scaled in color-coded 

symbols. The mean and standard deviation of |Avg| over all the 38 stations are 2.65 cm 

and 1.13 cm, respectively. 

 

(d) 

(d) 
16 

Figure 10. Comparisons of the modeled (a) MHHW, (b) MHW, (c) MLW, and (d) 

MLLW datums against observations using 38 tide stains. 

 

(a) 

(c) 

(b) 

(d) 
17 

Figure 11. Color-coded model-data differences at each observational station 

3.6.2. Match with Tidal Datums in Adjacent areas 

The present model domain overlaps with the previously developed North and Central 

California VDatum areas (Myers and Hess, 2005). Figure 12 illustrates the coverage of 

the two domains. In the figure, the yellow line delineates the North and Central California 

domain, while the red line delineates the present model domain. The green line denotes 

the 25-nm offshore limit. 

In reality, tidal datum fields should be matched seamlessly across the boundaries. 

However, this is not necessarily engendered when the two tidal datum fields were 

developed separately through slightly differing approaches and model setups. Therefore, 

it is worthwhile to examine discrepancies and work out ways to reach seamless matches 

if needed. 

In Figure 12, blue circles along transect AA’ correspond to grid nodes of the present 

hydrodynamic model, which are chosen to denote boundaries between the two model 

domains. Tidal datums from resources across the boundaries are compared over these 

locations. Four datums (MHHW, MHW, MLW, and MLLW) from within the Central and 
18 

Southern CA regions are separately interpolated onto the comparison locations. Figure 13 

shows the results along transect AA’. Table 1 tabulates the average tidal differences 

between the two models. In general, the differences are greater than 1 cm, which suggests 

the necessity of adjustments to reach seamless matching between the present results and 

those developed previously. Procedures for the adjustment are described in the next 

section. 

Figure 12. Map of the Southern California model domain (red line) and bounding 

polygons of the Central California VDatum region. Blue dots (transect AA’) 

represent the southern CA model grid nodes adjacent to the southern border 

of the central CA VDatum region. The green line delineates 25-nm offshore 

locations. 

 

A A’
19 

Table 1. The average differences of MHHW, MHW, MLW, and MLLW across 

boundaries of different VDatum regimes. 

Figure 13. Comparisons of tidal datums at discrete locations (blue symbols along transect 

AA’ in Figure 12), (a) MHHW, (b) MHW, (c) MLW, and (d) MLLW. The 

abscissa, Location Index, is counted from A to A’ (Figure 12. 

3.6.3. Corrections 

Tidal datum corrections were developed to eliminate model-data differences at 

observational stations (Section 3.6.1) as well as to eliminate datum discrepancies across 

boundaries of different VDatum domains (Section 3.6.2). This was achieved using the 

TCARI (Tidal Constituent And Residual Interpolation) spatial interpolation tool (Hess, 

Boundaries MHHW 

(cm) 

MHW 

(cm) 

MLW 

(cm) 

MLLW 

(cm) 

AA' 1.5 2.2 2.3 0.9 
20 

2000; Hess, 2002). TCARI spatially interpolates the error fields defined at a number of 

individual control stations onto the whole domain by solving Laplace’s equation. The 

technique was implemented for both structured or unstructured model grids, and a 

version of the latter was employed in this study. 

To run TCARI, both the observational stations and locations along the domain boundary 

are treated equally as control stations. For each tidal datum, both model-data differences 

(at 38 tidal stations) and across-boundary discrepancies (at 38 boundary locations) were 

computed and merged into one dataset for input to TCARI. 

After applying TCARI, error fields for MHHW, MHW, MLW, and MLLW were derived 

which matched the tidal datum differences at the 38 control stations. Figures 14(a)-(d) 

illustrate the four interpolated error fields, respectively. The initial model results (Section 

3.5) were then corrected by subtracting the error fields over the entire model grid. Figures 

15(a)-(d) display the four corrected datum fields relative to MSL. 

Note that the other two tidal datum fields, the MTL and DTL shown in Figures 15 (e) and 

(f), were produced in a different way. They were derived from the four corrected datums 

by taking the averages between MHW and MLW and between MHHW and MLLW, 

respectively. 
21 

Figure 14. TCARI interpolated tidal datum error fields on the unstructured grid, (a) 

MHHW, (b) MHW, (c) MLW, and (d) MLLW. Color bars are in the unit of 

meters. 

(a) 

MHHW 

(b) 

MHW 
22 

Figure 14. (Continued) 

(c) 

MLW 

(d) 

MLLW 
23 

Figure 15. Corrected tidal datum fields on the unstructured grid, (a) MHHW, (b) MHW, 

(c) MLW, (d) MLLW, (e) MTL, and (f) DTL. Color bars are in meters. 

(a) 

MHHW 

(b) 

MHW 
24 

Figure 15. (Continued)

(c) 

MLW 

(d) 

MLLW 
25 

Figure 15. (Continued) 

 

(e) 

MTL 

(f) 

DTL 
26 

 
27 

4. CREATION AND POPULATION OF THE MARINE GRID 

4.1. Creation of VDatum Marine Grid 

Tidal datums in the VDatum software are defined on a regularly structured grid, referred 

to as the marine grid (Hess and White, 2004). Hence, it is necessary to convert the tidal 

datum fields from the unstructured model grid onto the equally-spaced VDatum marine 

grid. 

Nodes in the marine grid were specified as either water points or land points. The water 

nodes are to be populated with valid tidal datum values and the land nodes are assigned 

with null values. To create and populate the marine grid, a high-resolution coastline and a 

bounding polygon were used (Figure 16). Only nodes within the bounding polygons or 

within up to one half of a cell size outside the coastline are delineated as water nodes; 

those outside of the bounding polygons or those more than one half of a cell size away 

from the coastline are marked as land nodes. 

Marine grid points are equally spaced within each region. For a point at the i-th row and 

j-th column relative to the point (longitude0, latitude0) at the region’s southwest corner, 

its location (longitude_i, latitude_j) is defined as, 

Longitude_i = longitude0 + (i-1)×del_lon, i=1, ..., N_lon, 

Latitude_j = latitude0 + (j-1) ×del_lat, j=1, ..., N_lat, 

where del_lon, and del_lat denote separation between neighboring points along the 

meridional and zonal directions, respectively; N_lon and N_lat represent, respectively, 

the longitude and latitude dimensions of the raster data set. It is noted that the del_lon and 

del_lat are prescribed parameters representing the expected grid resolutions, while N_lon

and N_lat are derived parameters according to 

N_lon = 1 + (longitude1 - longitude0)/del_lon 

N_lat = 1 + (latitude1 - latitude0)/del_lat 

where (longitude1, latitude1) are the coordinate at the raster region’s northeast corner. 

Table 2 lists the marine grid parameters used in the present study. 

 

Table 2. Marine grid parameters 

Marine 

Grids 

Longitude0 

(degree) 

Latitude0 

(degree) 

del_lon 

(degree)

del_lat 

(degree)

N_lon N_lat 

Southern 

California 

-122.03 32.25 0.001 0.001 5101 2891 
28 

Figure 16. The marine grid bounding polygon (blue line). The green line marks locations 

25-nautical miles offshore. The red line illustrates the open boundary of the 

hydrodynamic model. 

 

 
29 

4.2. Population of VDatum Grid with Tidal Datums 

Tidal datums on the VDatum marine grid were populated by interpolating TCARIcorrected tidal datums (Section 3.6) according to the algorithm of Hess and White (2004). 

Datums at each VDatum marine grid point were computed by averaging or linearly 

interpolating values within a user-specified searching radius or the closest user-specified 

number of points. In the present case, the interpolation was made using a FORTRAN 

program, vpop10.f. It populates marine points differently depending on whether the point 

is inside/outside of the ADCIRC model grid elements. If the point was inside an element, 

datums were calculated using an interpolation of the 3 nodes of the element; if the point 

is outside any elements, datums were computed using the inverse distance weighting of 

the closest two node values. Figures C.1 (a) – (f) display the populated tidal datums 

(MHHW, MHW, MLW, MLLW, MTL, DTL) defined on the marine grid (Section 4.1). 

Two types of verifications were conducted for the tidal datums populated on the marine 

grids: comparison with observations from the 38 CO-OPS tidal stations and examining 

the match across its boundaries with the central California VDatum application (Myers, 

2005). For each of the four datums (MHHW, MHW, MLW, and MLLW), both the 

average model-data error and the rms error are less than 1 mm. 

Datum fields across the boundaries of different VDatum regimes demonstrate good 

consistency as well. For each of MHHW, MHW, MLW, and MLLW, the average 

difference across the border between the Central California and the present VDatum 

regime is less than 1 mm. 
30 
31 

5. GENERATION OF TSS 

The TSS is defined as the elevation of NAVD 88 relative to local MSL. It is created by 

combining observed datums at NGS bench marks and CO-OPS water level stations with 

the tidal model results. Figure 17 illustrates the station locations used in this application 

(see details of the station information at Table D.1 of Appendix D). To create the TSS 

over the VDatum domain, the TSS values at the observation stations were first derived. 

These values were then interpolated over the whole domain. Afterwards, a quality control 

procedure was followed and appropriate changes were made to meet certain criteria. For 

the Southern California vicinity, the NAVD 88 heights are realized utilizing either 

GEOID99 or GEOID03, and therefore two sets of NAVD88 data were created. It is noted 

that the generation of both data sets shared the same algorithms and procedures. 

Figure 17. Location of tidal bench marks and tide stations used to compute the Southern 

California VDatum TSS grids. 
32 

5.1. Derivation of TSS 

Two methodologies were used to compute the TSS at the observational stations: an 

indirect method using data from the NGS database (see Appendix E) and a direct method 

using data from the CO-OPS database (see Appendix F). To derive the TSS at the NGS 

stations using the indirect method, residuals (Rdatum) at every NGS bench mark location 

are computed as: 

Rdatum = TBMnavd88 – TBMdatum + VDdatum

where TBMnavd88 and TBMdatum are the observed (NAVD88–MLLW) and (DatumMLLW) differences, respectively, and VDdatum denotes modeled (Datum–MSL) 

differences. The residual, Rdatum, represents an estimation of the (NAVD88-MSL) 

difference. 

There are four sets of Rdatum, corresponding to MHHW, MHW, MLW, and MLLW. Each 

represents an independent estimation of the quantity MSL–NAVD88 associated with a 

tidal datum. Tables E.1 and 2 list Rdatum’s at stations located within the VDatum bounding 

polygon (Figure 16). At each station, the four Rdatum’s are then averaged to produce a 

mean residual (Rdatum ). Rdatum represents an overall estimation of MSL–NAVD88 and is 

used for further development of the TSS grid. 

The TSS values at CO-OPS stations were simply derived by calculating orthometric-totidal datum relationships. Table D show the station location inventories and observations 

of elevation information. 

Next, the Rdatum values are merged with TSS values from CO-OPS stations to form a data 

set for creating a TSS mesh using the gridding software, Surfer©. A grid covering the 

entire area of bench marks and water level stations with a spatial resolution similar to that 

of the VDatum marine grid was created. Breaklines were inserted to represent the 

influence of land. The Surfer© software’s minimum curvature algorithm was employed 

to create a primary TSS field (TSSgrid) that honors the data as closely as possible. It is 

noted that the TSSgrid represents an estimation of the quantity MSL- NAVD88 and still 

requires further quality control and correction procedures (Section 5.2). Figures 18 shows 

the final TSS fields for the VDatum region (Table 2). In the figures, a positive value 

specifies that the NAVD 88 reference value is further from the center of the Earth than 

the local mean sea level surface. Figures 18 and 19 display the TSS fields based on 

NAVD88 realized through GEOID99 and GEOID03, respectively. Data derived from 

both the indirect and direct methodology are initially relative to NAVD88 realized 

through GEOID03. This data derived for both methods is transformed back through 

GEOID03 to an ellipsoidal reference and then transformed back utilizing GEOID99. 

Therefore, we now have two datasets for both methods, one relative to GEOID03 and the 

other relative to GEOID99. 
33 

Figure 18. The Southern California TSS field based on NAVD88 realized through 

GEOID99. 

 
34 

Figure 19. The Southern California TSS field based on NAVD88 realized through 

GEOID03. 

 
35 

5.2. Quality Control 

Quality control is necessary for obtaining a final TSS field. This is facilitated through 

examining the differences (R-TSS) between Rdatum and TSSgrid observational stations: 

R-TSS = -(Rdatum - TSSgrid) 

The R-TSS approximately represents the difference between the observed tidal datum and 

the datum as computed by the gridded fields. The mean R-TSS at each bench mark should 

be less than 0.01 m. If it is not, the input data and grids are checked, appropriate changes 

are made, and the values are recomputed until the criterion is met. This results in a final 

TSS field. Finally, a land mask is applied to denote the presence of land. 

A final quality control was conducted by evaluating mean R-TSS over four tidal datums 

(MHHW, MHW, MLW, and MLLW) at each bench mark station. Note that R-TSS

represents the difference between the observed and modeled tidal datums. The results 

gave mean (R-TSS) values that are less than the criteria value of 0.01 m. Tables F.1and 

F.2 of Appendix F tabulate the differences for TSS realized through GEOID99 and 

GEOID03, respectively. Tables G.1 and G.2 show the average mean R-TSS values and the 

corresponding standard deviations for each station. Both values were less than 510-3 m, 

thus indicating good model-data agreement. It should be noted that there is a lack of 

observational data offshore on the channel islands. Therefore consideration should be 

taken when utilizing these transformation results. 

 
36 

 
37 

6. SUMMARY 

In support of development of the national vertical datum transformation software tool, 

VDatum, tidal datum and TSS fields for the southern California coastal and adjacent 

water areas were developed in this study. Tidal datum fields were created by simulating 

tidal level time histories using the ADCIRC hydrodynamic model. The model domain 

was represented with an unstructured, triangular-element grid of 181,420 nodes and 

349,351 elements. ADCIRC simulations were forced with harmonic constants of 8 tidal 

constituents (M2, S2, N2, K2, K1, P1, O1, and Q1) along the model’s open ocean boundary. 

At each grid node, a water level time series spanning 5 days was used to compute four 

tidal datums, MHHW, MHW, MLW, and MLLW. 

Modeled results were verified by contrasting with observations at 38 CO-OPS water level 

stations. The average model-data discrepancy of the four datums was 3.8 cm, with a rms 

difference of 1.6 cm. The errors were interpolated over the whole model grid using the 

TCARI interpolation program. The resulting error fields were incorporated into the initial 

model results to derive error-corrected tidal datum fields. 

A regular VDatum marine grid was created to be used as input for the VDatum software 

tool. Tidal datums defined on the unstructured grid were interpolated onto the regular 

marine grid to form the final datums as input to VDatum. 

The TSS fields were created for the marine grid as well. They were derived using two 

methodologies: by fitting tidal model results to tidal bench marks leveled in NAVD88 

and by calculating orthometric-to-tidal datum relationships at NOAA water level gauges. 

Results from the two methods were coupled to create the final TSS grids and were 

incorporated into the VDatum tool. 

ACKNOWLEDGMENTS 

Authors would like to express gratitudes to CSDL’ Yuji Funakoshi, NGS’ Jason 

Woolard, and CO-OPS’ Stephen Gill for their time and effort to review this document. 

Their dedications substantially improve the quality of this document. 

REFERENCES 

Gill, S. K., and J. R. Schultz, 2001: Tidal Datums and Their Applications. Silver Spring, 

Maryland: U.S. Department of Commerce, National Oceanic and Atmospheric 

Administration, Silver Spring, MD. NOAA Special Publication NOS CO-OPS 1, 111 pp 

+ appendix. 

Hess, K. W, 2001: Generation of Tidal Datum Fields for Tampa Bay and the New York 

Bight. U.S. Department of Commerce, National Oceanic and Atmospheric 

Administration, Silver Spring, Maryland, NOAA Technical Report NOS CS 11, 43 pp. 
38 

___, 2002: Spatial interpolation of tidal data in irregularly-shaped coastal regions by 

numerical solution of Laplace’s equation. Estuarine, Coastal and Shelf Science, 54(2), 

175-192. 

___, 2003: Water level simulation in bays by spatial interpolation of tidal constituents, 

residual water levels, and datums. Continental Shelf Research, 23(5), 395-414. 

___, S. A. White, J. Sellars, E. A. Spargo, A. Wong, A. K., Gill, and C. Zervas, 2004. 

North Carolina Sea Level Rise: Interim Project Report. NOS Technical Memorandum

NOS CS 5, 26 pp. 

___, D. G. Milbert, S.K. Gill, and D.R. Roman, 2003: Vertical Datum Transformations 

for Kinematic GPS Hydrographic Surveys. Proceedings, U.S. Hydrographic Conference, 

March 24 – 27, 2003. Biloxi, MS. 8 pp. 

 ___, and S. K. Gill, 2003: Puget Sound Tidal Datums by Spatial Interpolation. 

Proceedings, Fifth Conference on Coastal Atmospheric and Oceanic Prediction and 

Processes. Am. Meteorological Soc., Seattle, August 6-8, 2003. Paper 6.1, 108 - 112. 

___, and S. A. White, 2004: VDatum for Puget Sound: Generation of the Grid and 

Population with Tidal Datums and Sea Surface Topography. U.S. Department of 

Commerce, National Oceanic and Atmospheric Administration, Silver Spring, Maryland, 

NOAA Technical Memorandum NOS CS 4, 27 pp. 

___, R. Wilson, D. Roman, and D. Milbert, 2004: Final Report on NOAA’s Work on the 

Southern Louisiana Coastal Topographic/bathymetric Project. Unpublished manuscript, 

12 pp. 

___, and E. Spargo (in preparation): TideSheet: An Updatable Astronomical Tide 

Database. 48 pp. 

___, E. A. Spargo, A. Wong, S. A. White, and S. K. Gill, 2005: VDatum for general 

coastal north Carolina: Generation of the marine grids and population with tidal datums 

and sea surface topography. Unpublished manuscript, 39 pp. 

Leuttich, Jr., R. A., J. L. Hench, C. W. Fulcher, F. E. Werner, B. O. Blanton, and J. H. 

Churchill, 1999: Barotropic tidal and wind driven larval transport in the vicinity of a 

barrier island inlet. Fisheries Oceanography, 33 (April), 913 – 932. 

Milbert, D. G. and K. W. Hess, 2001: Combination of Topography and Bathymetry 

Through Application of Calibrated Vertical Datum Transformations in the Tampa Bay 

Region. Preceedings of the 2nd Biennial Coastal GeoTools Conferences, Charleston, 

SC. 

Milbert, D.G., 2002: Documentation for VDatum (and VDatum Tutorial); Vertical Datum 

Transformation Software. Ver. 1.06 (nauticalcharts.noaa.gov/bathytopo/vdatum.htm). 
39 

Mukai, A. Y., J. J. Westerink, R. A. Luettich Jr., and D. Mark, 2002, Eastcoast 2001: A 

tidal constituent database for the western North Atlantic, Gulf of Mexico and Caribbean 

Sea, US Army Engineer Research and Development Center, Coastal and Hydraulics 

Laboratory, Technical Report, ERDC/CHL TR-02-24, September 2002, 201p. 

Myers, E., 2001: Generation of Tidal datums for Central California. Unpublished 

manuscript, 13 pp. 

Myers, E. and K. Hess. (2005). “Modeling of Tidal Datum Fields in Support of VDatum 

For the North and Central Coasts of California.” NOAA Technical Report, in preparation. 

Parker, B. P., 2002: The integration of bathymetry, topography, and shoreline, and the 

vertical datum transformations behind it. International Hydrographic Review (3) 3 

(November 2002). 

Parker, B., K. W. Hess, D. Milbert, and S. K. Gill, 2003: A national vertical datum 

transformation tool. Sea Technology, v. 44. no. 9 (Sept. 2003), 10-15. 

Spargo, E. A., and J. W. Woolard, 2005. VDatum for the Calcasieu River from Lake 

Charles to the Gulf of Mexico, Louisiana: Tidal Datum Modeling and Population of the 

Grid. NOS Technical Report NOS CS 19, 26 pp. 

Swanson, R. L., 1976: Tides. MESA New York Bight Atlans Monography Series 4. 

Albany, New York. New York Sea Grant Institute. 

Westerink, J. J., R. A. Luettich and J. C. Muccino, 1993: An Advanced ThreeDimensional Circulation Model for Shelves, Coasts, and Estuaries, Report 3: 

Development of a Tidal Constituent Database for the Western North Atlantic and Gulf of 

Mexico, Technical Report DRP-92-6, U.S. ACE Waterways Experiment Station, 

Vicksburg, MS. 
40 

 
41 

APPENDIX A. HORIZONTAL AND VERTICAL ACCURACY STANDARDS 

FOR NOAA BATHYMETRY SURVEY 

Table A.1. The required horizontal and vertical accuracy standards for NOAA surveys. 

Accuracy requirements before 1957 were prescribed for survey projects. 

Survey Year* Horizontal 

Accuracy 

Vertical 

Accuracy Standard 

1998 – present 

Order 1 

1 – 100 m depth: 

5.0 m + 5% of depth 

 

Order 2 

100 – 200 m depth: 

20 m + 5% of depth 

Order 3 

100 – 200 m depth: 

150 m + 5% of depth 

Order 1 

 1 – 100 m depth: 

0.5 – 1.4 m 

Order 2 

100 – 200 m depth: 

2.5 – 4.7 m 

 

Order 3 

> 100 m depth: 

same as Order 2 

IHO S-44 1

 

and NOAA 2 

1988 – 1998 

95% probability that the 

true position lies within a 

circle of radius 1.5 mm, at 

the scale of the survey 

0 – 30 m depth: 0.3 m 

> 30 m depth: 1% of depth 

IHO S-44 1 

and NOAA 2 

1982 – 1988 

probable error shall 

seldom exceed twice the 

plottable error (1.0 mm) at 

the scale of the survey 

0 – 20 m depth: 0.3 m 

20 – 100 m depth: 1.0 m 

> 100 m depth: 1% of depth 

IHO S-44 1

 

and NOAA 2 

1957 – 1982 

maximum error of plotted 

positions shall seldom 

exceed 1.5 mm at the 

scale of the survey 

0 – 20 m depth: 0.3 m 

20 – 100 m depth: 1.0 m 

> 100 m depth: 1% of depth 

IHC 3 

NOAA 2

and 

IHO S-44 1

before 1957 undetermined undetermined undocumente

d 

* end of field collection 1

 International Hydrographic Organization (IHO) Standards for Hydrographic Surveys, Special Publication 44, 

 (First Edition, 1968; Second Edition, 1982; Third Edition, 1987; Fourth Edition, 1998). 2

 U.S. Department of Commerce Coast and Geodetic Survey Hydrographic Manual (1931, 1942, 1960, 1976) 

 NOAA NOS Office of Coast Survey Specifications and Deliverables, 1999 – 2006. 

 NOAA was established in 1970. 

3

 International Hydrographic Conference, 1957. 

 
42 
43 

APPENDIX B. WATER LEVEL STATION DATA 

Table B.1. Tidal and orthometric datums (meters) relative to mean sea level for NOS 

water level stations in the Southern CA area. The ‘N/A’s in the table denote missing 

values. 

No. Station 

ID # 

Latitude 

(oN) 

Longitude 

(oW) 

MHHW 

(m) 

MHW 

(m) 

MLW 

(m) 

MLLW 

(m) 

NAVD88 

(m) Epoch Year 

1 9410032 -118.557 33.005 0.762 0.549 -0.549 -0.823 N/A N/A 

2 9410068 -119.497 33.2667 0.732 0.518 -0.488 -0.762 N/A N/A 

3 9410079 -118.325 33.345 0.792 0.579 -0.549 -0.823 N/A N/A 

4 9410092 -118.503 33.4317 0.762 0.549 -0.549 -0.823 N/A N/A 

5 9410120 -117.135 32.5783 0.798 0.575 -0.565 -0.839 0.074 1983-2001 

6 9410136 -117.113 32.6483 0.863 0.64 -0.64 -0.905 N/A 1960-1978 

7 9410152 -117.118 32.665 0.884 0.671 -0.64 -0.914 N/A N/A 

8 9410155 -117.233 32.6867 0.817 0.598 -0.594 -0.856 N/A 1960-1978 

9 9410166 -117.235 32.7033 0.823 0.579 -0.61 -0.884 N/A N/A 

10 9410169 -117.187 32.7117 0.838 0.616 -0.616 -0.881 N/A 1960-1978 

11 9410170 -117.173 32.7133 0.849 0.623 -0.611 -0.896 0.132 1983-2001 

12 9410175 -117.182 32.725 0.829 0.609 -0.61 -0.872 N/A 1960-1978 

13 9410191 -117.233 32.775 0.823 0.61 -0.579 -0.853 N/A N/A 

14 9410230 -117.258 32.8667 0.791 0.569 -0.557 -0.833 0.058 1983-2001 

15 9410384 -117.337 33.1433 0.768 0.521 -0.521 -0.771 N/A 1960-1978 

16 9410396 -117.395 33.21 0.798 0.573 -0.558 -0.832 N/A 1983-2001 

17 9410580 -117.883 33.6033 0.804 0.579 -0.566 -0.845 0.055 1983-2001 

18 9410583 -117.9 33.6 0.79 0.558 -0.555 -0.835 N/A 1960-1978 

19 9410614 -118.005 33.6533 0.787 0.561 -0.56 -0.847 N/A 1960-1978 

20 9410650 -118.273 33.7067 0.811 0.586 -0.574 -0.86 0.075 1983-2001 

21 9410660 -118.272 33.72 0.813 0.588 -0.574 -0.861 0.062 1983-2001 

22 9410680 -118.227 33.7517 0.815 0.59 -0.579 -0.866 N/A N/A 

23 9410683 -118.268 33.7533 0.805 0.586 -0.56 -0.853 N/A N/A 

24 9410738 -118.398 33.8467 0.789 0.564 -0.546 -0.833 N/A 1983-2001 

25 9410840 -118.5 34.0083 0.804 0.579 -0.566 -0.849 0.057 1983-2001 

26 9410842 -118.498 34.0067 0.808 0.579 -0.557 -0.844 N/A 1960-1978 

27 9410962 -120.047 34.0083 0.753 0.532 -0.519 -0.814 N/A 1983-2001 

28 9410971 -119.683 34.02 0.732 0.519 -0.518 -0.792 N/A N/A 

29 9410988 -120.355 34.0567 0.762 0.549 -0.518 -0.823 N/A N/A 

30 9411013 -119.098 34.1017 0.792 0.579 -0.549 -0.823 N/A N/A 

31 9411015 -119.095 34.0983 0.792 0.579 -0.549 -0.823 N/A N/A 

32 9411065 -119.203 34.1483 0.801 0.567 -0.567 -0.866 N/A 1960-1978 

33 9411270 -119.443 34.3483 0.803 0.573 -0.56 -0.861 0.03 1983-2001 

34 9411340 -119.685 34.4083 0.793 0.563 -0.55 -0.85 0.029 1983-2001 

35 9411405 -120.205 34.4683 0.762 0.549 -0.548 -0.853 N/A N/A 

36 9411406 -120.673 34.4683 0.807 0.565 -0.542 -0.847 N/A 1983-2001 

37 9412110 -120.76 35.1767 0.77 0.555 -0.536 -0.853 0.024 1983-2001 

38 9412113 -120.752 35.17 0.78 0.563 -0.546 -0.863 N/A 1960-1978 
44 

Table B.2. NOS Water Level Station Names 

No. Station ID # Station Name 

1 9410032 WILSON COVE SAN CLEMENTE IS CA 

2 9410068 SAN NICOLAS ISLAND CA 

3 9410079 AVALON SANTA CATALINA ISLAND CA 

4 9410092 CATALINA HAR SANTA CATALINA IS CA 

5 9410120 IMPERIAL BEACH PACIFIC OCEAN 

6 9410136 SWEETWATER CHANNEL CA 

7 9410152 NATIONAL CITY SAN DIEGO BAY CA 

8 9410155 BALLAST POINT CA 

9 9410166 U S QUARANTINE STATION S D BAY CA 

10 9410169 NORTH ISLAND NAVY WHARF CA 

11 9410170 SAN DIEGO SAN DIEGO BAY 

12 9410175 US COAST GUARD AIR STATION CA 

13 9410191 MISSION BAY CA 

14 9410230 LA JOLLA PACIFIC OCEAN 

15 9410384 AGUA HEDIONDA LAGOON CA 

16 9410396 OCEANSIDE HARBOR 

17 9410580 NEWPORT BEACH NEWPORT BAY ENTRANCE 

18 9410583 BALBOA CA 

19 9410614 HUNTINGTON BCH PIER CA 

20 9410650 CABRILLO BEACH 

21 9410660 LOS ANGELES OUTER HARBOR 

22 9410680 LONG BEACH TERMINAL ISLAND 

23 9410683 LONG BEACH TURNING BASIN CA 

24 9410738 KING HARBOR SANTA MONICA BAY 

25 9410840 SANTA MONICA PACIFIC OCEAN 

26 9410842 SANTA MONICA WLTS CA 

27 9410962 BECHERS BAY SANTA ROSA ISLAND 

28 9410971 PRISONERS HARBOR SANTA CRUZ IS CA 

29 9410988 CUYLER HARBOR SAN MIGUEL IS CA 

30 9411013 MUGU LAGOON BRIDGE CA 

31 9411015 MUGU LAGOON ENTRANCE CA 

32 9411065 PORT HUENEME CA 

33 9411270 RINCON ISLAND PACIFIC OCEAN 

34 9411340 SANTA BARBARA PACIFIC OCEAN 

35 9411405 GAVIOTA CA 

36 9411406 OIL PLATFORM HARVEST (TOPEX PROJECT) 

37 9412110 PORT SAN LUIS PACIFIC OCEAN 

38 9412113 PORT SAN LUIS WLTS CA 
45 

APPENDIX C. CORRECTED TIDAL DATUMS ON MARINE GRID 

Figure C.1. Tidal datums on marine grid, (a) MHHW, (b) MHW, (c) MLW, (d) MLLW, 

(e) MTL, and (f) DTL. Color bars are in the unit of meters. 

(a) 

MHHW 

(b) 

MHL 
46 

Figure C.1. (Continued) 

(c) 

MLW 

(d) 

MLLW 
47 

Figure C.1. (Continued) 

 

(e) 

MTL 
48 
49 

APPENDIX D. Tidal gauge and bench marks data used to create the TSS

Table D.1. Location and elevation information for NOAA water level gauges used 

to create the TSS grid. Tidal datums are relative to MLLW. MSL data are from 

CO-OPS and NAVD88 heights were calculated by NGS. 

Station 

ID 

Latitude 

(deg) 

Longitude 

(deg) 

MSL 

(m) 

NAVD88 

[GEOID03] 

(m) 

NAVD88 

[GEOID99] 

(m) 

TSS 

[GEOID03] 

(m) 

TSS 

[GEOID99] 

(m) 

9410120 32.57833 -117.13500 1.695 0.930 0.946 -0.765 -0.749 

9410170 32.71333 -117.17333 2.052 1.287 1.271 -0.765 -0.781 

9410230 32.86667 -117.25833 2.163 1.389 1.353 -0.774 -0.811 

9410580 33.60333 -117.88333 1.861 1.071 1.103 -0.790 -0.758 

9410650 33.70667 -118.27333 11.029 10.244 10.233 -0.785 -0.796 

9410660 33.72000 -118.27167 2.028 1.229 1.213 -0.799 -0.815 

9410840 34.00833 -118.50000 1.594 0.802 0.802 -0.792 -0.792 

9411270 34.34833 -119.44333 2.178 1.347 1.346 -0.831 -0.832 

9411340 34.40833 -119.68500 1.824 1.003 1.017 -0.821 -0.807 

9412110 35.17667 -120.76000 2.149 1.320 1.287 -0.829 -0.863 

 
50 

 
51 

APPENDIX E. DERIVED NAVD 88-TO-LMSL VALUES 

Table E.1. QC Deltas from the Southern California TSS Grid, based on NAVD88 

heights realized through GEOID 99. 

Benchmark Latitude Longitude 

From 

MLLW 

(m) 

From 

MLW 

(m) 

From 

MHW 

(m) 

From 

MHHW 

(m) 

Average 

(m) 

Std. 

Dev. 

(m) 

DC1339 32.57888 -117.13138 -0.747 -0.747 -0.747 -0.747 -0.747 0.000 

DC1340 32.57972 -117.13111 -0.748 -0.748 -0.748 -0.748 -0.748 0.000 

DC0888 32.71388 -117.17333 -0.777 -0.781 -0.781 -0.777 -0.779 0.002 

DC1322 32.71555 -117.17250 -0.771 -0.784 -0.789 -0.788 -0.783 0.008 

DC1313 32.86527 -117.25333 -0.808 -0.808 -0.814 -0.813 -0.811 0.003 

DC1312 32.86583 -117.25305 -0.811 -0.811 -0.817 -0.816 -0.814 0.003 

DC0986 32.86611 -117.25277 -0.811 -0.811 -0.817 -0.816 -0.814 0.003 

DC1308 32.86611 -117.25305 -0.808 -0.808 -0.814 -0.813 -0.811 0.003 

DC0990 32.86638 -117.25305 -0.808 -0.808 -0.814 -0.813 -0.811 0.003 

DC1310 32.86638 -117.25250 -0.805 -0.805 -0.811 -0.810 -0.808 0.003 

DX1969 33.60250 -117.88388 -0.758 -0.759 -0.758 -0.759 -0.758 0.001 

DX3663 33.60250 -117.88333 -0.758 -0.759 -0.758 -0.759 -0.758 0.001 

DX1968 33.60277 -117.88333 -0.758 -0.759 -0.758 -0.759 -0.758 0.001 

DX3420 33.60305 -117.88222 -0.755 -0.756 -0.755 -0.756 -0.755 0.001 

DX1967 33.60333 -117.88277 -0.758 -0.759 -0.758 -0.759 -0.758 0.001 

DX1970 33.60361 -117.88416 -0.759 -0.760 -0.758 -0.759 -0.759 0.001 

DY2509 33.70722 -118.27388 -0.798 -0.799 -0.797 -0.797 -0.798 0.001 

DY2508 33.70777 -118.27500 -0.792 -0.793 -0.791 -0.791 -0.792 0.001 

DY2507 33.70805 -118.27638 -0.789 -0.790 -0.788 -0.788 -0.789 0.001 

DY2506 33.70861 -118.27722 -0.797 -0.799 -0.799 -0.799 -0.798 0.001 

DY2505 33.70916 -118.27944 -0.787 -0.789 -0.797 -0.796 -0.792 0.005 

DY1100 33.70944 -118.28277 -0.783 -0.787 -0.799 -0.798 -0.792 0.008 

DY1099 33.71000 -118.28333 -0.801 -0.803 -0.801 -0.801 -0.801 0.001 

DY1083 33.71972 -118.27166 -0.812 -0.813 -0.813 -0.813 -0.813 0.000 

DY2515 33.72000 -118.27138 -0.813 -0.813 -0.813 -0.813 -0.813 0.000 

DY1080 33.72055 -118.27138 -0.816 -0.816 -0.816 -0.816 -0.816 0.000 

DY2514 33.72250 -118.27250 -0.816 -0.816 -0.817 -0.817 -0.816 0.000 

DY2513 33.72472 -118.27333 -0.816 -0.816 -0.817 -0.818 -0.817 0.001 

DY1085 33.72527 -118.27611 -0.813 -0.814 -0.815 -0.815 -0.814 0.001 

DY9300 33.72666 -118.27138 -0.819 -0.819 -0.820 -0.821 -0.820 0.001 

DY2512 33.72694 -118.27361 -0.813 -0.813 -0.814 -0.815 -0.814 0.001 

EW1586 34.01027 -118.49555 -0.787 -0.784 -0.793 -0.787 -0.788 0.004 

EW6485 34.34750 -119.44361 -0.834 -0.836 -0.834 -0.835 -0.835 0.001 

EW6484 34.34777 -119.44388 -0.834 -0.836 -0.834 -0.835 -0.835 0.001 

EW6804 34.35555 -119.44083 -0.822 -0.824 -0.821 -0.823 -0.823 0.001 

EW6807 34.35555 -119.44000 -0.795 -0.797 -0.794 -0.796 -0.796 0.001 

EW6481 34.35583 -119.44138 -0.819 -0.821 -0.818 -0.820 -0.820 0.001 

EW6480 34.35611 -119.44138 -0.801 -0.803 -0.800 -0.802 -0.802 0.001 

EW6488 34.35666 -119.43861 -0.825 -0.827 -0.824 -0.826 -0.825 0.001 

EW6801 34.35666 -119.44083 -0.810 -0.812 -0.809 -0.811 -0.810 0.001 

EW7026 34.41000 -119.69055 -0.809 -0.807 -0.809 -0.808 -0.808 0.001 

EW3742 34.41250 -119.68750 -0.809 -0.807 -0.808 -0.808 -0.808 0.001 

EW6796 34.41388 -119.68583 -0.811 -0.810 -0.811 -0.810 -0.811 0.000 

EW3748 34.41472 -119.68472 -0.808 -0.807 -0.807 -0.807 -0.807 0.001 
52 

Table E.2. QC Deltas from the Southern California TSS Grid, based on NAVD88 

heights realized through GEOID 03. 

PID Latitude 

(deg) 

Longitude 

(deg) 

MHHW 

Deltas 

(m) 

MHW 

Deltas 

(m) 

MLW 

Deltas 

(m) 

MLLW 

Deltas 

(m) 

Avg. 

(m) 

Std. 

Dev. 

(m) 

DC1339 32.57888 -117.13138 0.001 0.000 0.000 0.000 0.000 0.000 

DC1340 32.57972 -117.13111 0.000 0.000 0.000 0.000 0.000 0.000 

DC0888 32.71388 -117.17333 0.003 -0.001 -0.002 0.002 0.000 0.002 

DC1322 32.71555 -117.17250 0.010 -0.003 -0.008 -0.007 -0.002 0.008 

DC1313 32.86527 -117.25333 0.004 0.004 -0.002 -0.001 0.001 0.003 

DC1312 32.86583 -117.25305 0.001 0.001 -0.005 -0.004 -0.002 0.003 

DC0986 32.86611 -117.25277 0.001 0.000 -0.005 -0.005 -0.002 0.003 

DC1308 32.86611 -117.25305 0.004 0.004 -0.002 -0.001 0.001 0.003 

DC0990 32.86638 -117.25305 0.004 0.004 -0.002 -0.001 0.001 0.003 

DC1310 32.86638 -117.25250 0.007 0.006 0.001 0.001 0.004 0.003 

DX1969 33.60250 -117.88388 0.001 0.000 0.001 0.000 0.000 0.001 

DX3663 33.60250 -117.88333 0.001 0.000 0.000 0.000 0.000 0.001 

DX1968 33.60277 -117.88333 0.001 -0.001 0.001 0.000 0.000 0.001 

DX3420 33.60305 -117.88222 0.003 0.002 0.004 0.003 0.003 0.001 

DX1967 33.60333 -117.88277 0.000 -0.001 0.001 0.000 0.000 0.001 

DX1970 33.60361 -117.88416 0.000 -0.001 0.001 0.000 0.000 0.001 

DY2509 33.70722 -118.27388 -0.001 -0.002 0.000 0.000 -0.001 0.001 

DY2508 33.70777 -118.27500 0.000 -0.001 0.001 0.001 0.000 0.001 

DY2507 33.70805 -118.27638 0.002 0.000 0.002 0.002 0.002 0.001 

DY2506 33.70861 -118.27722 -0.001 -0.003 -0.003 -0.003 -0.003 0.001 

DY2505 33.70916 -118.27944 0.006 0.003 -0.004 -0.004 0.000 0.005 

DY1100 33.70944 -118.28277 0.012 0.009 -0.003 -0.003 0.004 0.008 

DY1099 33.71000 -118.28333 0.000 -0.001 0.000 0.001 0.000 0.001 

DY1083 33.71972 -118.27166 0.001 0.000 0.000 0.000 0.000 0.000 

DY2515 33.72000 -118.27138 0.001 0.000 0.000 0.000 0.000 0.000 

DY1080 33.72055 -118.27138 -0.001 -0.001 -0.001 -0.001 -0.001 0.000 

DY2514 33.72250 -118.27250 0.000 0.000 0.000 -0.001 0.000 0.000 

DY2513 33.72472 -118.27333 0.000 0.000 -0.001 -0.001 0.000 0.001 

DY1085 33.72527 -118.27611 0.001 0.000 -0.001 -0.001 0.000 0.001 

DY9300 33.72666 -118.27138 0.000 0.000 -0.001 -0.002 -0.001 0.001 

DY2512 33.72694 -118.27361 0.001 0.002 0.001 0.000 0.001 0.001 

EW1586 34.01027 -118.49555 0.001 0.004 -0.005 0.001 0.000 0.004 

EW6485 34.34750 -119.44361 0.000 -0.002 0.000 -0.002 -0.001 0.001 

EW6484 34.34777 -119.44388 0.000 -0.001 0.001 -0.001 0.000 0.001 

EW6804 34.35555 -119.44083 -0.011 -0.013 -0.010 -0.012 -0.012 0.001 

EW6807 34.35555 -119.44000 0.004 0.002 0.005 0.003 0.004 0.001 

EW6481 34.35583 -119.44138 -0.004 -0.006 -0.003 -0.005 -0.005 0.001 

EW6480 34.35611 -119.44138 0.014 0.012 0.015 0.013 0.013 0.001 

EW6488 34.35666 -119.43861 -0.003 -0.005 -0.002 -0.004 -0.004 0.001 

EW6801 34.35666 -119.44083 0.001 -0.001 0.002 0.000 0.000 0.001 

EW7026 34.41000 -119.69055 0.000 0.001 -0.001 0.000 0.000 0.001 

EW3742 34.41250 -119.68750 -0.001 0.000 0.000 0.000 0.000 0.001 

EW6796 34.41388 -119.68583 -0.001 0.000 -0.001 0.000 -0.001 0.000 

EW3748 34.41472 -119.68472 0.000 0.001 0.000 0.001 0.000 0.001 
53 

APPENDIX F. QA/QC Deltas at Stations for TSS Grids 

Table F.1. QC Deltas from the Southern California TSS Grid, based on 

NAVD88 heights realized through GEOID99. 

PID Latitude 

(deg) 

Longitude 

(deg) 

MHHW 

Deltas 

(m) 

MHW 

Deltas 

(m) 

MLW 

Deltas 

(m) 

MLLW 

Deltas 

(m) 

Avg. 

(m) 

Std. 

Dev. 

(m) 

DC1339 32.57888 -117.13138 0.001 0.000 0.000 0.000 0.000 0.000 

DC1340 32.57972 -117.13111 0.000 0.000 0.000 0.000 0.000 0.000 

DC0888 32.71388 -117.17333 0.003 -0.002 -0.002 0.002 0.000 0.002 

DC1322 32.71555 -117.17250 0.010 -0.003 -0.008 -0.007 -0.002 0.008 

DC1313 32.86527 -117.25333 0.004 0.004 -0.002 -0.001 0.001 0.003 

DC1312 32.86583 -117.25305 0.001 0.001 -0.005 -0.004 -0.002 0.003 

DC0986 32.86611 -117.25277 0.001 0.000 -0.005 -0.005 -0.002 0.003 

DC1308 32.86611 -117.25305 0.004 0.004 -0.002 -0.001 0.001 0.003 

DC0990 32.86638 -117.25305 0.004 0.004 -0.002 -0.001 0.001 0.003 

DC1310 32.86638 -117.25250 0.007 0.006 0.001 0.001 0.004 0.003 

DX1969 33.60250 -117.88388 0.001 0.000 0.001 0.000 0.000 0.001 

DX3663 33.60250 -117.88333 0.001 0.000 0.000 0.000 0.000 0.001 

DX1968 33.60277 -117.88333 0.001 -0.001 0.001 0.000 0.000 0.001 

DX3420 33.60305 -117.88222 0.003 0.002 0.004 0.003 0.003 0.001 

DX1967 33.60333 -117.88277 0.000 -0.001 0.001 0.000 0.000 0.001 

DX1970 33.60361 -117.88416 0.000 -0.001 0.001 0.000 0.000 0.001 

DY2509 33.70722 -118.27388 -0.001 -0.002 0.000 0.000 -0.001 0.001 

DY2508 33.70777 -118.27500 0.000 -0.001 0.001 0.001 0.000 0.001 

DY2507 33.70805 -118.27638 0.002 0.001 0.002 0.002 0.002 0.001 

DY2506 33.70861 -118.27722 -0.002 -0.003 -0.003 -0.003 -0.003 0.001 

DY2505 33.70916 -118.27944 0.006 0.003 -0.004 -0.004 0.001 0.005 

DY1100 33.70944 -118.28277 0.013 0.009 -0.003 -0.003 0.004 0.008 

DY1099 33.71000 -118.28333 0.000 -0.001 0.000 0.001 0.000 0.001 

DY1083 33.71972 -118.27166 0.001 0.000 0.000 0.000 0.000 0.000 

DY2515 33.72000 -118.27138 0.001 0.000 0.000 0.000 0.000 0.000 

DY1080 33.72055 -118.27138 -0.001 -0.001 -0.001 -0.001 -0.001 0.000 

DY2514 33.72250 -118.27250 0.000 0.000 0.000 -0.001 0.000 0.000 

DY2513 33.72472 -118.27333 0.000 0.000 -0.001 -0.001 -0.001 0.001 

DY1085 33.72527 -118.27611 0.001 0.000 -0.001 -0.001 0.000 0.001 

DY9300 33.72666 -118.27138 0.000 0.000 -0.001 -0.002 -0.001 0.001 

DY2512 33.72694 -118.27361 0.001 0.002 0.001 0.000 0.001 0.001 

EW1586 34.01027 -118.49555 0.001 0.004 -0.005 0.001 0.000 0.004 

EW6485 34.34750 -119.44361 0.000 -0.002 0.000 -0.002 -0.001 0.001 

EW6484 34.34777 -119.44388 0.000 -0.001 0.001 -0.001 0.000 0.001 

EW6804 34.35555 -119.44083 -0.011 -0.013 -0.010 -0.012 -0.012 0.001 

EW6807 34.35555 -119.44000 0.004 0.002 0.005 0.003 0.003 0.001 

EW6481 34.35583 -119.44138 -0.004 -0.006 -0.003 -0.005 -0.005 0.001 

EW6480 34.35611 -119.44138 0.014 0.012 0.015 0.013 0.013 0.001 

EW6488 34.35666 -119.43861 -0.004 -0.005 -0.003 -0.005 -0.004 0.001 

EW6801 34.35666 -119.44083 0.001 -0.001 0.002 0.000 0.000 0.001 

EW7026 34.41000 -119.69055 0.000 0.001 -0.001 0.000 0.000 0.001 
54 

EW3742 34.41250 -119.68750 -0.001 0.000 0.000 0.000 0.000 0.001 

EW6796 34.41388 -119.68583 -0.001 0.000 -0.001 0.000 0.000 0.000 

EW3748 34.41472 -119.68472 0.000 0.001 0.000 0.001 0.000 0.001 

Table F.2. QC Deltas from the Southern California TSS Grid, based on 

NAVD88 heights realized through GEOID 03. 

PID Latitude 

(deg) 

Longitude 

(deg) 

MHHW 

Deltas 

(m) 

MHW 

Deltas 

(m) 

MLW 

Deltas 

(m) 

MLLW 

Deltas 

(m) 

Avg. 

(m) 

Std. 

Dev. 

(m) 

DC1339 32.57888 -117.13138 0.001 0.000 0.000 0.000 0.000 0.000 

DC1340 32.57972 -117.13111 0.000 0.000 0.000 0.000 0.000 0.000 

DC0888 32.71388 -117.17333 0.003 -0.001 -0.002 0.002 0.000 0.002 

DC1322 32.71555 -117.17250 0.010 -0.003 -0.008 -0.007 -0.002 0.008 

DC1313 32.86527 -117.25333 0.004 0.004 -0.002 -0.001 0.001 0.003 

DC1312 32.86583 -117.25305 0.001 0.001 -0.005 -0.004 -0.002 0.003 

DC0986 32.86611 -117.25277 0.001 0.000 -0.005 -0.005 -0.002 0.003 

DC1308 32.86611 -117.25305 0.004 0.004 -0.002 -0.001 0.001 0.003 

DC0990 32.86638 -117.25305 0.004 0.004 -0.002 -0.001 0.001 0.003 

DC1310 32.86638 -117.25250 0.007 0.006 0.001 0.001 0.004 0.003 

DX1969 33.60250 -117.88388 0.001 0.000 0.001 0.000 0.000 0.001 

DX3663 33.60250 -117.88333 0.001 0.000 0.000 0.000 0.000 0.001 

DX1968 33.60277 -117.88333 0.001 -0.001 0.001 0.000 0.000 0.001 

DX3420 33.60305 -117.88222 0.003 0.002 0.004 0.003 0.003 0.001 

DX1967 33.60333 -117.88277 0.000 -0.001 0.001 0.000 0.000 0.001 

DX1970 33.60361 -117.88416 0.000 -0.001 0.001 0.000 0.000 0.001 

DY2509 33.70722 -118.27388 -0.001 -0.002 0.000 0.000 -0.001 0.001 

DY2508 33.70777 -118.27500 0.000 -0.001 0.001 0.001 0.000 0.001 

DY2507 33.70805 -118.27638 0.002 0.000 0.002 0.002 0.002 0.001 

DY2506 33.70861 -118.27722 -0.001 -0.003 -0.003 -0.003 -0.003 0.001 

DY2505 33.70916 -118.27944 0.006 0.003 -0.004 -0.004 0.000 0.005 

DY1100 33.70944 -118.28277 0.012 0.009 -0.003 -0.003 0.004 0.008 

DY1099 33.71000 -118.28333 0.000 -0.001 0.000 0.001 0.000 0.001 

DY1083 33.71972 -118.27166 0.001 0.000 0.000 0.000 0.000 0.000 

DY2515 33.72000 -118.27138 0.001 0.000 0.000 0.000 0.000 0.000 

DY1080 33.72055 -118.27138 -0.001 -0.001 -0.001 -0.001 -0.001 0.000 

DY2514 33.72250 -118.27250 0.000 0.000 0.000 -0.001 0.000 0.000 

DY2513 33.72472 -118.27333 0.000 0.000 -0.001 -0.001 0.000 0.001 

DY1085 33.72527 -118.27611 0.001 0.000 -0.001 -0.001 0.000 0.001 

DY9300 33.72666 -118.27138 0.000 0.000 -0.001 -0.002 -0.001 0.001 

DY2512 33.72694 -118.27361 0.001 0.002 0.001 0.000 0.001 0.001 

EW1586 34.01027 -118.49555 0.001 0.004 -0.005 0.001 0.000 0.004 

EW6485 34.34750 -119.44361 0.000 -0.002 0.000 -0.002 -0.001 0.001 

EW6484 34.34777 -119.44388 0.000 -0.001 0.001 -0.001 0.000 0.001 

EW6804 34.35555 -119.44083 -0.011 -0.013 -0.010 -0.012 -0.012 0.001 

EW6807 34.35555 -119.44000 0.004 0.002 0.005 0.003 0.004 0.001 

EW6481 34.35583 -119.44138 -0.004 -0.006 -0.003 -0.005 -0.005 0.001 

EW6480 34.35611 -119.44138 0.014 0.012 0.015 0.013 0.013 0.001 

EW6488 34.35666 -119.43861 -0.003 -0.005 -0.002 -0.004 -0.004 0.001 
55 

EW6801 34.35666 -119.44083 0.001 -0.001 0.002 0.000 0.000 0.001 

EW7026 34.41000 -119.69055 0.000 0.001 -0.001 0.000 0.000 0.001 

EW3742 34.41250 -119.68750 -0.001 0.000 0.000 0.000 0.000 0.001 

EW6796 34.41388 -119.68583 -0.001 0.000 -0.001 0.000 -0.001 0.000 

EW3748 34.41472 -119.68472 0.000 0.001 0.000 0.001 0.000 0.001 
56 

 
57 

APPENDIX G. COMPARISONS of DERIVED TSS WITH OBSERVATIONS AT 

TIDAL GAUGE AND TIDAL BENCH MARKS 

Table G.1. Southern California TSS Comparison to Tide Gauges and Tidal 

Bench marks. NAVD88 realized through GEOID99. 

ID Latitude 

(deg) 

Longitude 

(deg) 

NAVD 88 

to MSL (m) 

TSS 

Derived Value 

(m) 

Delta (m) 

9410120 32.57833 -117.13500 -0.7490 -0.7490 0.0000 

9410170 32.71333 -117.17333 -0.7810 -0.7801 0.0009 

9410230 32.86667 -117.25833 -0.8110 -0.8110 0.0000 

9410580 33.60333 -117.88333 -0.7580 -0.7584 -0.0004 

9410650 33.70667 -118.27333 -0.7960 -0.7963 -0.0003 

9410660 33.72000 -118.27167 -0.8150 -0.8134 0.0016 

9410840 34.00833 -118.50000 -0.7920 -0.7918 0.0002 

9411270 34.34833 -119.44333 -0.8320 -0.8321 -0.0001 

9411340 34.40833 -119.68500 -0.8070 -0.8071 -0.0001 

DC1339 32.57888 -117.13138 -0.7474 -0.7478 -0.0004 

DC1340 32.57972 -117.13111 -0.7476 -0.7478 -0.0002 

DC0888 32.71388 -117.17333 -0.7788 -0.7791 -0.0003 

DC1322 32.71555 -117.17250 -0.7830 -0.7808 0.0022 

DC1313 32.86527 -117.25333 -0.8107 -0.8119 -0.0012 

DC1312 32.86583 -117.25305 -0.8137 -0.8122 0.0015 

DC0986 32.86611 -117.25277 -0.8137 -0.8114 0.0023 

DC1308 32.86611 -117.25305 -0.8107 -0.8120 -0.0013 

DC0990 32.86638 -117.25305 -0.8107 -0.8118 -0.0011 

DC1310 32.86638 -117.25250 -0.8077 -0.8114 -0.0037 

DX1969 33.60250 -117.88388 -0.7584 -0.7586 -0.0002 

DX3663 33.60250 -117.88333 -0.7583 -0.7584 -0.0001 

DX1968 33.60277 -117.88333 -0.7584 -0.7584 0.0000 

DX3420 33.60305 -117.88222 -0.7553 -0.7583 -0.0030 

DX1967 33.60333 -117.88277 -0.7584 -0.7583 0.0001 

DX1970 33.60361 -117.88416 -0.7587 -0.7588 -0.0001 

DY2509 33.70722 -118.27388 -0.7977 -0.7971 0.0006 

DY2508 33.70777 -118.27500 -0.7917 -0.7921 -0.0004 

DY2507 33.70805 -118.27638 -0.7887 -0.7903 -0.0016 

DY2506 33.70861 -118.27722 -0.7984 -0.7956 0.0028 

DY2505 33.70916 -118.27944 -0.7923 -0.7927 -0.0004 

DY1100 33.70944 -118.28277 -0.7920 -0.7959 -0.0039 

DY1099 33.71000 -118.28333 -0.8014 -0.8012 0.0002 

DY1083 33.71972 -118.27166 -0.8126 -0.8129 -0.0003 

DY2515 33.72000 -118.27138 -0.8127 -0.8131 -0.0004 

DY1080 33.72055 -118.27138 -0.8158 -0.8145 0.0013 

DY2514 33.72250 -118.27250 -0.8162 -0.8162 0.0000 

DY2513 33.72472 -118.27333 -0.8167 -0.8162 0.0005 

DY1085 33.72527 -118.27611 -0.8139 -0.8137 0.0002 

DY9300 33.72666 -118.27138 -0.8199 -0.8190 0.0009 

DY2512 33.72694 -118.27361 -0.8137 -0.8146 -0.0009 
58 

EW1586 34.01027 -118.49555 -0.7877 -0.7877 0.0000 

EW6485 34.34750 -119.44361 -0.8348 -0.8339 0.0009 

EW6484 34.34777 -119.44388 -0.8347 -0.8344 0.0003 

EW6804 34.35555 -119.44083 -0.8227 -0.8112 0.0115 

EW6807 34.35555 -119.44000 -0.7957 -0.7991 -0.0034 

EW6481 34.35583 -119.44138 -0.8197 -0.8151 0.0046 

EW6480 34.35611 -119.44138 -0.8016 -0.8149 -0.0133 

EW6488 34.35666 -119.43861 -0.8254 -0.8214 0.0040 

EW6801 34.35666 -119.44083 -0.8104 -0.8107 -0.0003 

EW7026 34.41000 -119.69055 -0.8082 -0.8081 0.0001 

EW3742 34.41250 -119.68750 -0.8078 -0.8077 0.0001 

EW6796 34.41388 -119.68583 -0.8105 -0.8101 0.0004 

EW3748 34.41472 -119.68472 -0.8074 -0.8078 -0.0004 

Table G.2. Southern California TSS Comparison to Tide Gauges and Tidal 

Bench marks. NAVD88 is realized through GEOID03. 

ID Latitud

e (deg) 

Longitud

e (deg) 

NAVD 

88 to MSL 

(m) 

TSS 

Derived 

Value 

(m) 

Delta 

(m) 

9410120 32.57833 -117.13500 -0.765 -0.765 0.0001 

9410170 32.71333 -117.17333 -0.765 -0.764 0.0009 

9410230 32.86667 -117.25833 -0.774 -0.774 0.0000 

9410580 33.60333 -117.88333 -0.790 -0.790 -0.0002 

9410650 33.70667 -118.27333 -0.785 -0.785 -0.0003 

9410660 33.72000 -118.27167 -0.799 -0.797 0.0016 

9410840 34.00833 -118.50000 -0.792 -0.792 0.0001 

9411270 34.34833 -119.44333 -0.831 -0.831 -0.0003 

9411340 34.40833 -119.68500 -0.821 -0.821 -0.0001 

DC1339 32.57888 -117.13138 -0.763 -0.763 -0.0004 

DC1340 32.57972 -117.13111 -0.763 -0.763 -0.0004 

DC0888 32.71388 -117.17333 -0.763 -0.763 -0.0003 

DC1322 32.71555 -117.17250 -0.767 -0.764 0.0021 

DC1313 32.86527 -117.25333 -0.774 -0.775 -0.0011 

DC1312 32.86583 -117.25305 -0.777 -0.776 0.0017 

DC0986 32.86611 -117.25277 -0.777 -0.775 0.0023 

DC1308 32.86611 -117.25305 -0.774 -0.776 -0.0012 

DC0990 32.86638 -117.25305 -0.774 -0.775 -0.0010 

DC1310 32.86638 -117.25250 -0.771 -0.775 -0.0037 

DX1969 33.60250 -117.88388 -0.790 -0.790 -0.0001 

DX3663 33.60250 -117.88333 -0.790 -0.790 0.0000 

DX1968 33.60277 -117.88333 -0.790 -0.790 -0.0001 

DX3420 33.60305 -117.88222 -0.787 -0.790 -0.0030 

DX1967 33.60333 -117.88277 -0.790 -0.790 0.0000 

DX1970 33.60361 -117.88416 -0.790 -0.790 -0.0001 

DY2509 33.70722 -118.27388 -0.787 -0.786 0.0006 

DY2508 33.70777 -118.27500 -0.781 -0.781 -0.0004 

DY2507 33.70805 -118.27638 -0.778 -0.779 -0.0015 

DY2506 33.70861 -118.27722 -0.787 -0.784 0.0026 
59 

DY2505 33.70916 -118.27944 -0.781 -0.781 -0.0003 

DY1100 33.70944 -118.28277 -0.781 -0.784 -0.0037 

DY1099 33.71000 -118.28333 -0.790 -0.790 0.0001 

DY1083 33.71972 -118.27166 -0.797 -0.797 -0.0004 

DY2515 33.72000 -118.27138 -0.797 -0.797 -0.0005 

DY1080 33.72055 -118.27138 -0.800 -0.798 0.0012 

DY2514 33.72250 -118.27250 -0.800 -0.800 0.0001 

DY2513 33.72472 -118.27333 -0.800 -0.799 0.0004 

DY1085 33.72527 -118.27611 -0.797 -0.797 0.0003 

DY9300 33.72666 -118.27138 -0.802 -0.802 0.0008 

DY2512 33.72694 -118.27361 -0.796 -0.797 -0.0009 

EW1586 34.01027 -118.49555 -0.788 -0.788 0.0000 

EW6485 34.34750 -119.44361 -0.834 -0.833 0.0009 

EW6484 34.34777 -119.44388 -0.834 -0.834 0.0003 

EW6804 34.35555 -119.44083 -0.824 -0.813 0.0115 

EW6807 34.35555 -119.44000 -0.797 -0.800 -0.0034 

EW6481 34.35583 -119.44138 -0.821 -0.816 0.0048 

EW6480 34.35611 -119.44138 -0.803 -0.816 -0.0131 

EW6488 34.35666 -119.43861 -0.827 -0.823 0.0038 

EW6801 34.35666 -119.44083 -0.812 -0.812 -0.0002 

EW7026 34.41000 -119.69055 -0.823 -0.823 0.0001 

EW3742 34.41250 -119.68750 -0.823 -0.823 0.0002 

EW6796 34.41388 -119.68583 -0.826 -0.826 0.0005 

EW3748 34.41472 -119.68472 -0.823 -0.823 -0.0003