Geoids Data in Ensemble JFF format

Note: All the geoid models are given with respect to WGS84 datum.

To add a global or a regional geoid model, or a segment of a regional geoid model to use in Ensemble, follow these steps:

1. Download and unzip a file with a geoid.
2. Start Ensemble.
3. Open Coordinate System and Geoid editor, go to the Geoid page.
4. Press the Import button and locate the corresponding geoid *.jff file in the directory where you unzipped the downloaded file.

You may delete both ZIP and JFF file after import.

• Global Geoid Models
• Regional NOAA Geoid-2003 model for USA (GEOID03)
• Regional NOAA Geoid-99 model for USA (GEOID99)
• Regional NOAA Geoid-96 model for USA (GEOID96)
• Regional Ordnance Survey Geoid Model 2002 for Great Britain (OSGM02)

Global Geoid Models

Note: In Ensemble global geoid model, EGM96 is used in its original form, without any topographic corrections.

GAO98.zip (999,039 bytes)
EGM96.zip (1,974,898 bytes)
GRIM5-S1.zip (148,882 bytes)

Regional Geoid Models

Regional NOAA Geoid-2003 model for USA (GEOID03)

Conterminous United States

Note: GEOID03 is a refined model of the geoid in the conterminous United States (CONUS), which supersedes the previous models GEOID90, GEOID93, GEOID96, and GEOID99. For CONUS, GEOID03 heights range from a low of -50.01 meters in the Atlantic Ocean to a high of 3.43 meters in the Labrador Strait. However, these geoid heights are only reliable within CONUS due to the limited extents of the data used to compute it. GEOID03 models will not be created for other regions. Instead, new models will be created next year (GEOID04) for all U.S. states and territories.

G2003u01.zip (58 - 40 N & 130 - 111 W) 3,778,713 bytes
G2003u02.zip (58 - 40 N & 113 - 94 W)3,862,053 bytes
G2003u03.zip (58 - 40 N & 96 - 77 W) 3,719,809 bytes
G2003u04.zip (58 - 40 N & 79 - 60 W) 4,055,228 bytes
G2003u05.zip (42 - 24 N & 130 - 111 W) 3,779,156 bytes
G2003u06.zip (42 - 24 N & 113 - 94 W) 3,848,127 bytes
G2003u07.zip (42 - 24 N & 96 - 77 W) 3,723,933 bytes
G2003u08.zip (42 - 24 N & 79 - 60 W) 3,845,004 bytes

Regional NOAA Geoid-99 model for USA (GEOID99)

Note: NOAA Geoid-99 is given relative to NAD83 datum. Ensemble assumes all geoid models it imports are given with respect to WGS84 datum. So we had to recalculate NOAA Geoid-99 files accordingly.

Alaska

G99AKNW.zip (72 - 60 N & 172 - 204 E) 4,822,507 bytes
G99AKNE.zip (72 - 60 N & 202 - 234 E) 4,909,445 bytes
G99AKSW.zip (61 - 49 N & 172 - 204 E) 4,936,577 bytes
G99AKSE.zip (61 - 49 N & 202 - 234 E) 5,011,610 bytes

Conterminous United States

G99N1.zip (58 - 40 N & 230 - 249 E) 4,145,902 bytes
G99N2.zip (58 - 40 N & 247 - 266 E) 4,168,951 bytes
G99N3.zip (58 - 40 N & 264 - 283 E) 4,015,465 bytes
G99N4.zip (58 - 40 N & 281 - 300 E) 4,268,815 bytes
G99S1.zip (42 - 24 N & 230 - 249 E) 4,049,848 bytes
G99S2.zip (42 - 24 N & 247 - 266 E) 4,161,695 bytes
G99S3.zip (42 - 24 N & 264 - 283 E) 4,078,480 bytes
G99S4.zip (42 - 24 N & 281 - 300 E) 4,071,559 bytes

Hawaii

G99HI.zip (24 - 18 N & 199 - 206 E) 535,867 bytes

Puerto Rico

G99PR.zip (21 - 15 N & 291 - 296 E) 350,754 bytes

Regional NOAA Geoid-96 model for USA (GEOID96)

Alaska

G96AN.zip (N60 - N72 & W179 - W128) 988,369 bytes
G96AS.zip (N51 - N63 & W179 - W128) 994,548 bytes

Conterminous United States

G96NC.zip (N36 - N50 & W107 - W84) 992,515 bytes
G96NE.zip (N36 - N50 & W89 - W66) 965,255 bytes
G96NW.zip (N36 - N50 & W125 - W102) 983,271 bytes
G96SC.zip (N24 - N38 & W107 - W84) 964,537 bytes
G96SE.zip (N24 - N38 & W 89 - W66) 991,825 bytes
G96SW.zip (N24 - N38 & W125 - W102) 991,646 bytes

Hawaii

G96HW.zip (N18 - N24 & W151 - W154) 136,968 bytes

Puerto Rico

G96PR.zip (N15 - N21 & W68 - W64) 72,318 bytes

Regional Ordnance Survey Geoid Model 2002 for Great Britain (OSGM02)

OSGM02.zip (N49°45'30" - N61°01'00" & W09°23'30" - E03°33'30") 2,014,557 bytes

Note: Please bear in mind the following when using OSGM02 in Ensemble:

• OSGM02 is a regional geoid model for latitudes from N49°45'30" to N61°01'00" and longitudes from W09°23'30" to E03°33'30".
• OSGM02 gives real geoid heights only for the land and within a 10 km zone around it but not for the sea (if you try to get geoid heights for the sea the model gives "9999").
• OSGM02 has been converted to WGS84 for use in Ensemple, so you can get only geoid heights referred to WGS84 ellipsoid (not above ETRS89 ellipsoid as in the original model).

Accuracy of geiod model OSGM02 is about a few centimeters, so in Ensemble with this model you can get orthometric height with standard error about 3-5 cm.