3/29/12, "New paper confirms 2010 Russian heat wave was result of natural variability," Hockeyschtick blog
Monthly Weather Review 2012 ; e-View
"Large scale flow and the long-lasting blocking high over Russia: Summer 2010"
Abstract"Several studies show that the anomalous long-lasting Russian heat wave in summer 2010, linked to a long-persistent blocking high, appears as a result of natural atmospheric variability. This study analyzes the large scale flow structure based on ERA-Interim data (1989 to 2010). The anomalous long-lasting blocking high over Western Russia including the heat wave occurs as an overlay of a set of anticyclonic contributions on different time scales: (i) A regime change in ENSO towards La Niña modulates the quasi-stationary wave structure in the boreal summer hemisphere supporting the eastern European blocking. The polar Arctic dipole mode is enhanced and shows a projection on the mean blocking high. (ii) Together with the quasi-stationary wave anomaly the transient eddies maintain the long-lasting blocking. (iii) Three different pathways of wave action are identified on the intermediate time scale (~ 10-60 days). One pathway commences over the eastern North Pacific and includes the polar Arctic region; another one runs more southward and crossing the North Atlantic, continues to eastern Europe; a third pathway southeast of the blocking high describes the downstream development over South Asia."...
"Ongoing Scientific Assessment of the 2010 Russian Heat Wave," NOAA Earth system Research Laboratory"
After the preliminary assessement was completed a more comprehensive analysis was performed, leading to a peer-reviewed paper in Geophysical Research Letters:
- Dole, R. M. Hoerling, J. Perlwitz, J. Eischeid, P. Pegion, T. Zhang, X. Quan, T. Xu, and D. Murray
Geophys. Res. Lett., 38, L06702, doi:10.1029/2010GL046582
The 2010 summer heat wave in western Russia was extraordinary, with the region experiencing the warmest July since at least 1880 and numerous locations setting all-time maximum temperature records....Analysis of forced model simulations indicates that neither human influences nor other slowly evolving ocean boundary conditions contributed substantially to the magnitude of this heat wave. They also provide evidence that such an intense event could be produced through natural variability alone."...