Apr 26, 2019

Extreme weather events in early summer 2018 connected by a recurrent hemispheric wave-7 pattern

Kai Kornhuber, Scott Osprey, Dim Coumou, Stefan Petri, Vladimir Petoukhov, Stefan Rahmstorf, Lesley Gray
Environmental Research Letters
  • The summer of 2018 witnessed a number of extreme weather events such as heatwaves in North America, Western Europe and the Caspian Sea region, and rainfall extremes in South-East Europe and Japan that occurred near-simultaneously
  • Shows that some of these extremes were connected by an amplified hemisphere-wide wavenumber 7 circulation pattern
  • Shows that this pattern constitutes an important teleconnection in Northern Hemisphere summer associated with prolonged and above-normal temperatures in North America, Western Europe and the Caspian Sea region
  • Finds that this pattern was also observed during the European heatwaves of 2003, 2006 and 2015 among others
  • Shows that the occurrence of this wave 7 pattern has increased over recent decades