nawqa_perm is a polygon coverage of the permafrost regions
in the Cook Inlet National Water-Quality Assessment (NAWQA) study unit.
The Cook Inlet Basin is located in southcentral Alaska. Values of the item
PERMAFROST in the polygon attribute table indicate the relative type of
permafrost for each polygon.
The purpose of this nawqa_perm was to develop a database of the various basin characteristics of the Cook Inlet Basin. This coverage, along with other coverages, will be used as a guide for selecting water-quality sampling sites.
Procedures_Used:
A statewide coverage of the permafrost map of Alaska was obtained from the USGS EROS field office in Anchorage. The coverage was then edited using the basin boundaries of the Cook Inlet Basin to obtain the final coverage.
Revisions:
No revisions have been made.
Reviews_Applied_to_Data:
Roy Glass reviewed the final edited coverage. An editorial review of the documentation was done by Liska Snyder.
Related_Spatial_and_Tabular_Data_Sets:
None
Other_References_Cited:
Ferrians, Jr., O.J., 1965, Permafrost map of Alaska: U.S. Geological Survey Miscellaneous Investigations Series, Map I-445, 1 sheet.
Notes:
None
No updates are planned unless new data become available.
None
Point_of_Contact USGS-WRD
The coverage was developed from a 1:2,500,000 map. Thus, caution should be used when analyzing the coverage at smaller scales.
Thanks are due to the USGS EROS Data Center, Anchorage, AK
Standard items are found in the polygon attribute table with the exception of the item called PERMAFROST. The codes for this item are as follows: 0 is Cook Inlet; 12 - generally free of permafrost, fine grain deposits, (mountainous areas); 13 - generally underlain by isolated masses of permafrost, (mountainous areas); 22 - generally underlain by moderately thick to thin permafrost,(lowland, upland areas); 25 - underlain by isolated masses of permafrost, (lowland, upland areas); 26 - generally free of permafrost, (lowland, upland areas); and 31 - generally free of permafrost (outside permafrost region).