The orginal precipitation map was done on a 1:2,000,000 scale mylar map of Alaska. The isolines were digitized from the mylar and entered into ARC-INFO. In ARC-EDIT, the isolines were joined with an outline of Alaska (1:250,000 scale to create the digitized precipitation map. The amount of precipitation for each polygon was determined to be the average value between bounding isolines.
Revisions:
This precipitation map of Alaska represents the most current version (1994). As more data and/or new techniques become available, the map will be updated. In 1998, there were no plans to update the map.
Reviews_Applied_to_Data:
Reviews of the digitized data were done by Emily Binnian, Stan Jones, Tim Brabets, Ben Kennedy, and Roy Glass. A review of the documentation was done by Roy Glass. Editorial review of the documentation was done by Liska Snyder.
References_Cited:
Jones, S.H., and Fahl, C.B., 1994, Magnitude and frequency of floods in Alaska and conterminous basins of Canada: U.S. Geological Survey Water-Resources Investigations Report 93-4179, 122 p., 2 plates.
The precipitation map was developed using a relatively small number of precipitation stations and the map has large intervals between contours of equal annual precipitation. Thus caution should be used when interpreting precipitation values. The original map was prepared on a 1:2,000,000 scale. Thus, scales smaller than this should be used with caution.
Completeness_Report
N/A
Horizontal_Positional_Accuracy_Report
Unknown
Vertical_Positional_Accuracy_Report
N/A
Cloud_Cover
N/A