Please note: Special Studies data, analysis, and interpretation are preliminary and subject to revision. These results have not been peer reviewed for publication, but they are provided herein to help NADP data users understand various characteristics and limitations of NADP data. The USGS External Quality Assurance Program for the NADP has determined that these studies are important, but not worthy of publication in peer reviewed journals or U.S. government reports. These results have been presented in NADP business meetings and technical symposia, and the presentations are documented in NADP meeting minutes.

For citation purposes, the following in-text reference is suggested:
Greg Wetherbee, U.S. Geological Survey, written communication, date, URL.

AeroChem / N-CON Collector Comparison

Arvada, Colorado-Urban Site Instrument Photographs

Belfort / OTT Rain Gage Comparison for Snow Measurement

Isopleth Maps Generated Using PRISM Precipitation Estimates

Sample Evaporation Study

Weather Does Not Affect Measurement Error

Historical / Discontinued QA Programs

NTN 2006 Blind Audit of CAL Detection Limits