Global Hydrographic Data, Release 2.3 (GGHYDRO)

Global Hydrographic Data (GGHYDRO) was compiled in the mid-1980s (Cogley, 1988) as a tool for helping to describe the world's land surfaces to general circulation climate models. While more accurate or more highly resolved descriptions of the contents of some of the fields are now available, GGHYDRO Release 2.3 retains its original advantages of moderate size, internal consistency and useful content. It has been corrected periodically as errors have been detected.

GGHYDRO Release 2.3 is organized into 21 fields containing terrain type, stream frequency counts, major drainage basins, main features of the cryosphere surface, and ice/water runoff per year for the entire Earth's surface at a spatial resolution of 1 degree longitude by 1 degree latitude. Coverage includes the following:

Dry land (percent) (LAND)
Perennial freshwater lakes (percent) (FLAK)
Swamp, marsh and other wetlands (percent) (SWMP)
Salt lakes (percent) (SLAK)
Salt water of the ocean (percent) (OCEA)
Intermittent water bodies (percent) (ILAK)
Glacier ice, including shelf ice but excluding pack ice (percent) (GLAC)
Sand dunes (percent) (DUNE)
Saltmarsh (percent) (SMRS)
Salt flats (percent) (SFLT)
Land + Swamp + Sand dunes + Saltmarsh (percent) (DSRF)
Saltwater, marine or terrestrial (percent) (SLTW)
Perennial rivers (counts) (FRIV)
Intermittent rivers (counts) (IRIV)
Surface runoff of water (mm/a) (RNOF)
Estimated root-mean-square error of RNOF (%) (RNER)
Runoff of ice (mm/a) (RICE)
Land mask (MS05)
Major drainage basins (BAS1)
Smaller drainage basins (BAS2)
Main features of the cryosphere (CRYO)

The Global Hydrographic data set is available for download from Trent University at [http://www.trentu.ca/academic/geography/glaciology/glglgghy.htm]. Documentation, FORTRAN read utilities, and references are also available from this site.

More details about the content of GGHYDRO are provided by Cogley (2003), who also describes the format of the data and the compression scheme used to reduce file sizes. A more modern compression scheme is in development.

References

Cogley, J. G. 2003. GGHYDRO - Global Hydrographic Data, Release 2.3, Trent Technical Note 2003-1, Department of Geography, Trent University, Peterborough, Ontario, Canada.

Cogley, J. G. 1998. GGHYDRO - Global Hydrographic Data, Release 2.2, Trent Climate Note 98-1, Department of Geography, Trent University, Peterborough, Ontario, Canada.