J.R. Slack Alan M. Lumb Jurate Maciunas Landwehr 19941230 Unknown 1.0 map USGS Water Resources Investigations Report 93-4076 Reston, Virginia, USA U.S. Geological Survey http://water.usgs.gov/lookup/getspatial?hcdn A streamflow data set, which is specifically suitable for the study of surface-water conditions throughout the United States under fluctuations in the prevailing climatic conditions, has been developed. This data set, called the Hydro-Climatic Data Network, or HCDN, consists of streamflow records for 1,659 sites throughout United States and its Territories. The potential consequences of climate change to continental water resources are of great concern in the management of those resources. Critically important to society is what effect fluctuations in the prevailing climate may have on hydrologic conditions, such as the occurrence and magnitude of floods or droughts and the seasonal distribution of water supplies within a region. Records of streamflow that are unaffected by artificial diversions, storage, or other works of man in or on the natural stream channels or in the watershed can provide an account of hydrologic responses to fluctuations in climate. By examining such records given known past meteorologic conditions, we can better understand hydrologic responses to those conditions and anticipate the effects of postulated changes in current climate regimes. Furthermore, patterns in streamflow records can indicate when a change in the prevailing climate regime may have occurred in the past, even in the absence of concurrent meteorologic records. 1874 1988 1988 Complete Completed -125.0000 -66.0000 50.0000 24.0000 None hydrologic climate inlandWaters None None U.S. Geological Survey mailing address

12201 Sunrise Valley Drive, MS 440

Reston VA 20192 USA 1-888-275-8747 h2oteam@usgs.gov Please use email. CD or on-line data sets See the full report for more information. See the full report for more information. Records for the HCDN were obtained through a comprehensive search of the extensive surface-water data holdings of the U.S. Geological Survey (USGS) which are contained in the USGS National Water Storage and Retrieval System (WATSTORE). All streamflow discharge records in WATSTORE through September 30, 1988, were examined for inclusion in the HCDN in accordance with strictly defined criteria of measurement accuracy and natural conditions. No reconstructed records of "natural flow" were permitted, nor was any record extended or had missing values "filled in" using computational algorithms. If the streamflow at a station was judged to be free of controls for only a part of the entire period of record that is available for the station, then only that part was included in the HCDN, but only if it was of sufficient length (generally 20 years) to warrant inclusion. In addition to the daily mean discharge values, complete station identification information and basin characteristics were retrieved from WATSTORE for inclusion in the HCDN. Statistical characteristics, including the monthly mean discharge, as well as the annual mean, minimum and maximum discharge values, were derived for the records in the HCDN data set. The HCDN includes data values for discharge measured at 1,659 streamflow gaging stations. Records cumulatively span the period 1874 through 1988, inclusive, and represent a total of 73,231 water years of information. See the full report for more information. 19940101 Vector Point 4092 String 9547 GT-polygon composed of chains 4093 Albers Conical Equal Area 29.5 45.5 -96 23 0.0 0.0 coordinate pair 1.0 1.0 meters n/a n/a n/a See detailed report for more information. See detailed report for more information. U.S. Geological Survey Ask USGS - Water Webserver Team mailing

445 National Center

Reston VA 20192 1-888-275-8747 (1-888-ASK-USGS) http://water.usgs.gov/user_feedback_form.html Although this data set has been used by the U.S. Geological Survey, U.S. Department of the Interior, no warranty expressed or implied is made by the U.S. Geological Survey as to the accuracy of the data and related materials. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the U.S. Geological Survey in the use of this data, software, or related materials. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Other On-line data http://water.usgs.gov/pubs/wri/wri934076/1st_page.html None. This dataset is provided by USGS as a public service. 20041108 U.S. Geological Survey Ask USGS -- Water Webserver Team mailing

445 National Center

Reston VA 20192 1-888-275-8747 (1-888-ASK-USGS) http://answers.usgs.gov/cgi-bin/gsanswers?pemail=h2oteam&subject=GIS+Dataset+hcdn FGDC Content Standards for Digital Geospatial Metadata FGDC-STD-001-1998