Jan 11, 2016

Increasing Daily Precipitation Intensity Associated with Warmer Air Temperatures over Northern Eurasia

Hengchun Ye, Eric J. Fetzer, Ali Behrangi, Sun Wong, Bjorn H. Lambrigtsen, Crysti Y. Wang, Judah Cohen, and Brandi L. Gamelin
American Meteorological Society
  • Uses 45 years of observational records from 517 historical surface weather stations over northern Eurasia to examine changing precipitation characteristics associated with increasing air temperatures
  • Results suggest that warming air temperatures over northern Eurasia have been accompanied by higher precipitation intensity but lower frequency and little change in annual precipitation total
  • Finds an increase in daily precipitation intensity of around 1%–3% per each degree of air temperature increase for all seasons as long as a station’s seasonal mean air temperature is below about 15°–16°C
    • States that this threshold temperature may be location dependent
    • Finds that at temperatures above this threshold, precipitation intensity switches to decreasing with increasing air temperature, possibly related to decreasing water vapor associated with extreme high temperatures
  • Notes that the major atmospheric circulation of the Arctic Oscillation, Scandinavian pattern, east Atlantic–western Eurasian pattern, and polar–Eurasian pattern also have significant influences on precipitation intensity in winter, spring, and summer over certain areas of northern Eurasia