THE ROLE OF SOIL AND VEGETATION FOR CLIMATE VARIABILITY AND CLIMATE
CHANGE
Sonia I. Seneviratne, Edouard Davin, Adriaan J. Teuling and Eric B. Jaeger
ETH Zurich, Universitätstrasse 16, CHN M 16.2, CH-8092 Zürich, Switzerland; e-mail:
edouard.davin@env.ethz.ch
This presentation provides an overview on the role of soil-vegetation-atmosphere interactions for
climate variability and climate change (e.g. Seneviratne et al. 2006a,b, 2009).
Soil characteristics, soil moisture content, as well as vegetation cover, dynamics and physiology
all significantly impact land-atmosphere exchanges, especially in transitional climate regions. This
is particularly relevant in the context of climate change, as shifts in climate regimes, and
associated shifts in the location of transitional climate regions, can lead to significant changes in
climate variability due to enhanced land-atmosphere coupling. This is the case for Central and
Eastern Europe, where this effect is shown to lead to an enhancement of the variability of
summer climate with enhanced greenhouse gas concentrations, potentially causing more
frequent heatwaves and heavy precipitation events (Seneviratne et al. 2006a). Moreover, soil
moisture also constitutes an important memory component for the climate system (Seneviratne et
al. 2006b). Finally, land-atmosphere interactions, through the role of vegetation control for
evapotranspiration and photosynthesis, represent a key link between the water, energy and
biogeochemical cycles (e.g. Davin et al. 2007, Seneviratne et al. 2009). However, large
uncertainties remain regarding the accurate representation of the relevant processes in current
climate models (e.g. Seneviratne et al. 2006b, Pitman et al. 2009), in particular due to the lack of
observational data.
These results highlight the need for a better understanding, monitoring, and modelling of land
surface processes and soil-vegetation-atmosphere interactions. Examples of recent research
developments will be presented in the areas of vegetation-climate modeling (e.g. Davin et al.
2009), and model-data integration (e.g. Teuling et al. 2009, Jaeger et al. 2009), along with
opening perspectives in the fields of climate, hydrological and ecosystem modeling.
References:
Davin, E.L., N. de Noblet-Ducoudré, and P. Friedlingstein, 2007: Impact of land cover change on
surface climate: Relevance of the radiative forcing concept, Geophys. Res. Lett., 34, L13702,
doi:10.1029/2007GL029678.
Davin, E.L., R. Stöckli, and S.I. Seneviratne, 2009: A new version of the COSMO regional climate
model coupled to the Community Land Model. In preparation.
Jaeger, E.B., R. Stöckli and S.I. Seneviratne, 2009: Analysis of planetary boundary layer fluxes
and land-atmosphere coupling in the Regional Climate Model CLM. J. Geophys. Res. Atmospheres, conditionally accepted.
Seneviratne, S.I., D. Lüthi, M. Litschi, and C. Schär, 2006a: Land-atmosphere coupling and
climate change in Europe. Nature, 443, 205-209.
Seneviratne, S.I., R.D. Koster, Z. Guo, P.A. Dirmeyer, E. Kowalczyk, D. Lawrence, P. Liu, C.-H.
Lu, D. Mocko, K.W. Oleson, and D. Verseghy, 2006: Soil moisture memory in AGCM simulations:
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Seneviratne, S.I., T. Corti, E.L. Davin, M. Hirschi, I. Lehner, and A.J. Teuling, 2009: Investigating
soil moisture-climate interactions in a changing climate: A review. Submitted to Earth-Science
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