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Hydrology, Hydrologic cycle -- Forecasting, Thermal pollution of rivers lakes etc., Water temperature -- Oregon, Upper air temperature -- Measurement


We investigated trends in air temperature, stream temperature and discharge for rivers across the continental United States from the summer months of 1996 to 2016. Using GAGES II from USGS and PRISM and programming language R we analyzed specific hydrological trends in Mann-Kendall’s tests. After collecting the slope values whether they were negative or positive and the P-Values, the significance of that slope, we mapped slopes of trends in GIS. Stream temperature increased 12% of stations across the summer, while air temperature increased 22% of stations, and discharge decreased 15% of stations, respectively. Seven day moving average of daily maximum stream temperature increased and other basin characteristics such as precipitation, dam storage, latitude, and vegetation coverage were other influences of that increase. Oregon showed the least number of increasing trends for stream temperature.


Presentations associated with the report are available below in the Additional Files.

Persistent Identifier

flores-symposium.pdf (5114 kB)
2018 Symposium presentation

flores-ignite.pdf (1876 kB)
Ignite presentation