Hot European Summers and the Role of Soil Moisture in the Propagation of Mediterranean Drought

Abstract Drought in spring and early summer has been shown to precede anomalous hot summer temperature. In particular, drought in the Mediterranean region has been recently shown to precede and to contribute to the development of extreme heat in continental Europe. In this paper, this mechanism is investigated by performing integrations of a regional mesoscale model at the scale of the European continent in order to reproduce hot summer inception, starting with different initial values of soil moisture south of 46°N. The mesoscale model is driven by the large-scale atmospheric conditions corresponding to the 10 hottest summers on record from the European Climate Assessment dataset. A northward progression of heat and drought from late spring to summer is observed from the Mediterranean regions, which leads to a further increase of temperature during summer in temperate continental Europe. Dry air formed over dry soils in the Mediterranean region induces less convection and diminished cloudiness, which get...

[1]  J. D. Tarpley,et al.  Implementation of Noah land surface model advances in the National Centers for Environmental Prediction operational mesoscale Eta model , 2003 .

[2]  Pascal Yiou,et al.  Summertime European heat and drought waves induced by wintertime Mediterranean rainfall deficit , 2007 .

[3]  T. D. Mitchell,et al.  An improved method of constructing a database of monthly climate observations and associated high‐resolution grids , 2005 .

[4]  H. Wanner,et al.  Summer heat waves over western Europe 1880–2003, their relationship to large-scale forcings and predictability , 2007 .

[5]  J. Dudhia.  A Nonhydrostatic Version of the Penn State–NCAR Mesoscale Model: Validation Tests and Simulation of an Atlantic Cyclone and Cold Front , 1993 .

[6]  Huug van den Dool,et al.  Analysis of model-calculated soil moisture over the United States (1931-1993) and applications to long-range temperature forecasts , 1996 .

[7]  E. Fischer,et al.  Soil Moisture–Atmosphere Interactions during the 2003 European Summer Heat Wave , 2007 .

[8]  R. Reynolds,et al.  The NCEP/NCAR 40-Year Reanalysis Project , 1996, Renewable Energy.

[9]  M. Beniston.  The 2003 heat wave in Europe: A shape of things to come? An analysis based on Swiss climatological data and model simulations , 2004 .

[10]  M. Blackburn,et al.  Factors contributing to the summer 2003 European heatwave , 2004 .

[11]  S. Seneviratne,et al.  Land–atmosphere coupling and climate change in Europe , 2006, Nature.

[12]  E. Fischer,et al.  Contribution of land‐atmosphere coupling to recent European summer heat waves , 2007 .

[13]  Jon Sáenz,et al.  Sensitivity of the MM5 mesoscale model to physical parameterizations for regional climate studies: Annual cycle , 2007 .

[14]  X. Bian,et al.  Evaluation of real-time high-resolution MM5 predictions over the Great Lakes region , 2005 .

[15]  Pedro Viterbo,et al.  The European Summer of 2003: Sensitivity to Soil Water Initial Conditions , 2006 .

[16]  D. Lüthi,et al.  The role of increasing temperature variability in European summer heatwaves , 2004, Nature.

[17]  D. Lüthi,et al.  The Soil-Precipitation Feedback: A Process Study with a Regional Climate Model , 1999 .

[18]  J. Shukla,et al.  Role of Mediterranean SST in enhancing the European heat wave of summer 2003 , 2007 .

[19]  A. Phillips,et al.  Tropical Atlantic Influence on European Heat Waves , 2005 .

[20]  R. Vautard,et al.  Hot and cool summers: Multiple equilibria of the continental water cycle , 2006 .

[21]  J. Wallace,et al.  Meteorological Conditions during Heat Waves and Droughts in the United States Great Plains , 1987 .

[22]  M. Ek,et al.  The Influence of Atmospheric Stability on Potential Evaporation , 1984 .

[23]  Huug van den Dool,et al.  Climate Prediction Center global monthly soil moisture data set at 0.5 resolution for 1948 to present , 2004 .