Location: Forage and Livestock Production ResearchTitle: Kansas trends and changes in temperature, precipitation, drought, and frost-free days from the 1890s to 2015
|Lin, Xiaomao - KANSAS STATE UNIVERSITY|
|Harrington Jr., John - KANSAS STATE UNIVERSITY|
|Ciampitti, Ignacio - TEXAS TECH 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: 1/2/2018
Citation: Lin, X., Harrington Jr., J., Ciampitti, I., Gowda, P., Brown, D.P., Kisekka, I. 2018. 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.
Interpretive Summary: Accurate, historical climate information is a key resource for managing Kansas water resources and improving agricultural production. As the climate of Kansas continues to vary over time, information on past conditions and ongoing trends will help those managing other climate-sensitive resources across the state. Average temperatures in Kansas have significantly trended up during last 121 years, a period in which the daily minimum temperature increased faster than the daily maximum temperature. The warming rate in Kansas, 0.06 oC per decade, is comparable with the U.S. as well as global warming rates (approximately 0.07 oC per decade). This primarily nighttime warming might not directly drive evapotranspiration loss as a whole, but it could have significant impacts on crop production especially for winter wheat, one of the major crops in Kansas. Long-term observed precipitation in the state did not exhibit any significant trends. Only western Kansas tended to be drier in more recent years, while central and eastern Kansas tended to be wetter. The frost free season length, in contrast, demonstrated a clear and statistically significant increase across all of Kansas. These differences mirror the overall spatial trends of more warming in eastern Kanas driven primarily by nighttime temperatures
Technical Abstract: Kansas extends 660 km from the moderate elevations and semi-humid conditions of the Lower Missouri Basin to the High Plains lying above the Ogallala aquifer and along the Rockies’ eastern slope. Such characteristics result in significant climate variability across the state, making timely and accurate climate trend and change information valuable for water resources management and crop production. Here we used high-quality daily and monthly climate observations spanning a long-term period of 121 years (1895-2015) to assess trends and changes in air temperature, precipitation, drought, and frost-free days across Kansas. We show that a statewide average warming rate of 0.06oC per decade was mainly driven by trends in daily minimum temperatures. However, there were no statistically significant trends in precipitation in either western, central, or eastern Kansas. Western Kansas tended towards increasing dryness, but central and eastern Kansas trended wetter as indicated by changes in the Palmer Drought Severity Index (PDSI), a trend that was consistent with a weak wetting signal in eastern Kansas. The length of frost-free season has increased by 5.2 days in western, 7.2 days in central, and 12.6 days in eastern Kansas, respectively, which reflected more warming in the east and less in the west, especially for changing magnitudes of nighttime temperatures. Such increases of frost-free days especially in moisture-limited areas (e.g., western Kansas) might increase seasonal evapotranspiration loss, thus exacerbating soil moisture stress and associated management challenges.