DEVELOPING A REGIONAL RECORD OF HISTORIC TEMPERATURE CHANGES FROM 1893 TO 2021 IN THE TRI-STATE AREA OF OHIO, INDIANA, AND KENTUCKY

To mitigate the impacts of climate change, universities, municipalities, and city governments across the U.S. are developing and adopting climate change resilience plans. In general, these plans assess the threats that climate change poses to their respective communities based on the historic and predicted changes in local climate. A variety of tools exist to help these organizations develop their resilience plans within the US Climate Action Toolkit, a set of climate resources operated by an inter-agency research group and maintained by NOAA. To inform Miami University’s Climate Resilience Report, we used the Climate Explorer tool within the U.S. Climate Action Toolkit to access historic temperature data in the region. We examined daily maximum and minimum temperature records from 8 stations within 50 miles of Miami University. These records have variable start dates, including 1893 (Greenville, OH; Dayton, OH), 1925 (Brookville, IN), 1935 (Dayton International Airport, OH), 1947 (Cincinnati International Airport, KY), 1950 (Cincinnati Fern Bank, OH), 1968 (Richmond, IN), and 1970 (Cheviot, OH). We noted a tremendous range among the stations on a given day for both maximum and minimum temperatures. 1,510 days had a range of 20°F or greater among the reported maximum temperatures, and 1,019 days had a range of 20°F or greater among the reported minimum temperatures. We resolved the discrepancies in the data by removing days with temperature ranges of greater than 20°F from the data set, then used multiple linear regression to assess temperature changes for this region over the last 128 years. We see a warming trend of 0.0107°F per year for minimum temperatures (R² = 0.74, p < 2.2 x 10^-16) and 0.00706°F per year for maximum temperatures (R² = 0.77, p = 1.3 x 10^-8) throughout the study period. Over the course of the 128-year study period, we see an increase of 1.37°F in minimum temperatures and a 0.90°F increase in maximum temperatures. When days with large ranges are considered in the models, we see an increase of 1.28°F for minimum temperatures (R² = 0.74, p < 2.2 x 10^-16) and 1.23°F for maximum temperatures (R² = 0.76, p = 3.5 x 10^-15) across the 128-year study period.