UNESCO River Discharge Database Development

The original UNESCO site and discharge data were entered from a hardcopy series of publications entitled "The Discharge of Selected Rivers of the World" which were published in book form from 1969 through 1984. The series has served as an important source of information on approximately 1000 stations. These were checked against existing digital UNESCO station data (NOAA - National Geophysical Data Center; WMO - Global Runoff Data Center) to form a comprehensive set of discharge sites for which summary discharge data was developed. An example of the discharge data developed for each site shows a range of information about each site.

Below is an overview of the methodology used to develop and error-check the data entries:

• The data were stored in two related tables, one with the discharge station information, and one table with the discharge data itself. An example of the tables that were created is here. These two tables were linked via a common Geographical Reference Code (GeoRep).

• When the latitude and longitude for a site were not listed, the Times Atlas of the World was consulted to derive the coordinates . If the given discharge station name was not present in the Times Atlas, or in any local maps that were available to us, the latitude and logitude were calculated from the UNESCO GeoRep given. For example, iF03 = -80 longitude, 53 latitude. These points were imported into Arc/Info (ESRI, Redlands, California) and displayed over the ArcWorld (1:3000000) rivers coverage (ESRI), where their coordinates were adjusted to lie directly upon the approprite river.

• When there was no GeoRep available, as was often the case with the digital data, the site was discarded.

• When a site had little or no associated descriptive data, the site was discarded.