Air temperatures are sometimes used as substitutes for stream temperatures. To
examine the errors associated with this substitution, linear relationships between 43
Minnesota stream water temperature records and associated air temperature records were
analyzed. Weather monitoring stations were, on average, 23.3 miles from the stream
stations. From the lumped data set (38,082 data pairs), the general equations,
Tw=4.4+0.81Ta, Tw= 1. 9+0. 97 Ta., Tw=0.7+1.04Ta, and Tw=3.3+0.89Ta ,with temperatures in
°e, were derived for daily, weekly, monthly, and yearly mean temperatures, respectively.
Standard deviations between all measured and predicted water temperatures were 3.soe
(daily), 2.6°e (weekly), 1.9°e (monthly), and 1.3°e (yearly). Separate analyses for each
specific stream gave lower standard deviations. The measured water temperatures follow
the annual air temperature cycle closely. No time lags were taken into account, and
periods of ice cover were excluded from the analysis.
National Agricultural Water Quality Laboratory, US Department of Agriculture
Pilgrim, John M.; Fang, Xing; Stefan, Heinz G..
Correlations of Minnesota Stream Water Temperatures with Air Temperatures.
St. Anthony Falls Laboratory.
Retrieved from the University of Minnesota Digital Conservancy,
Content distributed via the University of Minnesota's Digital Conservancy may be subject to additional license and use restrictions applied by the depositor.