http://marine.rutgers.edu/~francis/pres/Francis_Vavrus_2012GL051000_pub.pdf
Two effects are identified that each contribute to a slower eastward progression of Rossby
waves in the upper-level flow: 1) weakened zonal winds, and 2) increased wave amplitude. These effects are particularly evident in autumn and winter consistent with sea-ice loss, but are also apparent in summer, possibly related to
earlier snow melt on high-latitude land. Slower progression of upper-level waves would cause associated weather patterns in mid-latitudes to be more persistent, which may lead to an increased probability of extreme weather events that result from prolonged conditions, such as drought, flooding, cold spells, and heat waves.
Quote selectie