An observational case study of mesoscale atmospheric circulations induced by soil moisture
Taylor, Christopher M.; Parker, Douglas J.; Harris, Philip P.. 2007 An observational case study of mesoscale atmospheric circulations induced by soil moisture. Geophysical Research Letters, 34, L15801. 6, pp. 10.1029/2007GL030572Before downloading, please read NORA policies.
Numerical and theoretical studies have shown that mesoscale gradients in land surface properties can induce circulations in the atmosphere. This study provides the first well-resolved observations of such flows induced by soil moisture from recent rainfall, and is based on aircraft data in the Sahel. Satellite imagery was used to identify fine scale soil moisture features within a wet zone spanning 160 km. Above the wet soil, the planetary boundary layer was up to 3 K cooler, 3 gkg−1 moister and extended to only half the depth of nearby drier areas. Mesoscale perturbations to the background flow were found, consistent with low level divergence over wet soil and convergence in drier areas. The soil moisture and atmospheric wind patterns were statistically coherent on wavelengths down to 20 km. These results suggest that mesoscale convergence lines forced by soil moisture may play a significant role in the meteorology of the Sahel.
|Item Type:||Publication - Article|
|Digital Object Identifier (DOI):||10.1029/2007GL030572|
|Programmes:||CEH Programmes pre-2009 publications > Biogeochemistry > CC01B Land-surface Feedbacks in the Climate System > CC01.8 Land-surface feedbacks through energy and water cycles|
|CEH Sections:||Harding (to July 2011)|
|Additional Keywords:||mesoscale circulations, soil moisture, Sahel NO|
|NORA Subject Terms:||Meteorology and Climatology
|Date made live:||23 Aug 2007 15:54|
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