Observed relation between evapotranspiration and soil moisture in the North American monsoon region
نویسندگان
چکیده
[1] Soil moisture control on evapotranspiration is poorly understood in ecosystems experiencing seasonal greening. In this study, we utilize a set of multi-year observations at four eddy covariance sites along a latitudinal gradient in vegetation greening to infer the ET-q relation during the North American monsoon. Results reveal significant seasonal, interannual and ecosystem variations in the observed ET-q relation directly linked to vegetation greening. In particular, monsoon-dominated ecosystems adjust their ET-q relation, through changes in unstressed ET and plant stress threshold, to cope with differences in water availability. Comparisons of the observed relations to the North American Regional Reanalysis dataset reveal large biases that increase where vegetation greening is more significant. The analysis presented here can be used to guide improvements in land surface model parameterization in water-limited ecosystems. Citation: Vivoni, E. R., H. A. Moreno, G. Mascaro, J. C. Rodriguez, C. J. Watts, J. GaratuzaPayan, and R. L. Scott (2008), Observed relation between evapotranspiration and soil moisture in the North American monsoon region, Geophys. Res. Lett., 35, L22403, doi:10.1029/ 2008GL036001.
منابع مشابه
Spatial extent of the North American Monsoon: Increased cross- regional linkages via atmospheric pathways
[1] The North American monsoon is a key feature affecting summer climate over Southwestern North America. During the monsoon, evapotranspiration from the Southwest promotes transference of water to the atmosphere which is subsequently distributed across the continent linking the SW to other regions via atmospheric hydrologic connectivity. However, the degree to which atmospheric connectivity re...
متن کاملAnálisis de retroalimentaciones suelo-atmósfera en América del Sur empleando un nuevo modelo climático regional
The primary objective of the present thesis is to contribute to the understanding of the soil moisture – atmosphere interaction during the development and mature phases of the South American monsoon system. A set of dynamical downscaling experiments over the continent are developed and analyzed for this purpose, using the Rossby Centre Atmospheric regional model (RCA). The primary objective lea...
متن کاملImpact of spatially-variable soil thickness and texture on simulated hydrologic conditions in a semiarid watershed in northwest Mexico
Soil depth and texture exert strong controls on the spatial distribution of water and energy fluxes and states in semiarid watersheds. As a result, realistic representations of the spatial soil characteristics within watersheds are important for the improvement of process-based distributed hydrologic modeling applications. In this study, we evaluated the effects of combinations of soil thicknes...
متن کاملQuantifying mesoscale soil moisture with the cosmic-ray rover
Soil moisture governs the surface fluxes of mass and energy and is a major influence on floods and drought. Existing techniques measure soil moisture either at a point or over a large area many kilometers across. To bridge these two scales we used the cosmic-ray rover, an instrument similar to the recently developed COSMOS probe, but bigger and mobile. This paper explores the challenges and opp...
متن کاملERS scatterometer surface soil moisture analysis of two sites in the south and north of the Sahel region of West Africa
The analysis of feedback effects between continental surfaces and the atmosphere is a key element in the understanding of African monsoon dynamics. For this reason, the monitoring of surface parameters, in particular soil moisture, is essential. Satellite remote sensing appears to be the most suitable means of obtaining data relevant to such parameters. The present paper presents the results of...
متن کامل