|LIN, X. - Kansas State University|
|HARRINGTON, JOHN - Kansas State University|
|CIAMPITTI, IGNACIO - Kansas State University|
|KISEKKA, ISAYA - Kansas State University|
Submitted to: Journal of Contemporary Water Research and Education
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/3/2017
Publication Date: 12/28/2017
Citation: Lin, X., Harrington, J., Ciampitti, I., Gowda, P.H., Brown, D.P., Kisekka, I. 2017. Kansas trends and changes in temperature, precipitation, drought, and frost-free days from the 1890s to 2015. Journal of Contemporary Water Research and Education. 162: 18-30. https://doi.org/10.1111/j.1936-704X.2017.03257.x.
Interpretive Summary: Spatial gradients and temporal variability of weather and climate across Kansas have significant influences on the state’s water availability and associated crop production. It is essential to understand these spatio-temporal patterns in order to provide water and agricultural managers and decision-makers with accurate information regarding past, current, and projected future weather and climate information. This study examined daily and monthly patterns and variations in a number of climate variables (temperature, precipitation, drought, frost-free days) in Kansas over a 121-year period. The results of the analyses highlight clear warming temperature trends and a reduction in the number of frost-free days across the state, but no discernable trend in precipitation and associated drought occurrence. The study suggests a higher confidence exists when projecting future temperature-associated impacts on water and agriculture in Kansas, and less confidence in projecting precipitation-based impacts. Land managers may also need to account for greater moisture stress on crops in western Kansas in the future, where increases in frost-free days may impact seasonal evapotranspiration rates.
Technical Abstract: Kansas extends 660 kilometers from the moderate elevations and semi-humid conditions of the lower Missouri Basin to the High Plains lying above the High Plains aquifer and along the Rockies’ eastern slope. Such characteristics make Kansas climate variability relatively significant which leads the climate trend and change information valuable to the water resources and crop production. Here we use high-quality daily and monthly climate observations spinning a long-term period of 121 years from 1895 to 2015 to assess Kansas trends and changes of temperature, precipitation, drought, and frost-free days. We show that a warming rate of 0.06oC per decade in Kansas temperature was mainly driven by the daily minimum temperature. However, the precipitation didn’t present any statistically significant trends in western, central, and eastern Kansas. Statistically, only western Kansas tended to be drier but the central and eastern Kansas tended to be wetter in terms of the Palmer Drought Severity Index (PDSI), which tendency was consistent with a weak wetting trend of precipitation in eastern Kansas. The length of frost-free season has been increased by 5.2 days in the western, 7.2 days in the central, and 12.6 days in the eastern Kansas, which reflected the more warming in the eastern area and less warming in the western areas especially for changing magnitudes of nighttime temperatures. Such increases of frost-free days especially in moisture-limited areas (e.g., the western Kansas) might increase evapotranspiration loss, which might drive this semiarid area dryer.