Vegetation Influence on Regional Climate Change: A 3D Integrated Atmospheric-Surface-Subsurface Analysis
Abstract
Human induced land-use change has been shown to be one of the major contributing factors to anthropogenic regional climate change. The transition from densely vegetated forests with deep root zones to shallow rooted agricultural ecosystems drastically limits the natural buffering capacity of deep groundwater during severe drought conditions. In order to quantify the magnitude of climate change from altered ecosystems, we employed the 3D model HydroGeoSphere, an integrated variably-saturated subsurface/surface flow and heat transport model, coupled with a simplified zero-dimensional atmospheric boundary layer model to simulate an extended seasonal drought period. It is found that during drought conditions, trees with deep root zones are capable of maintaining higher evapotranspiration rates, higher latent heat fluxes, and a damped atmospheric temperature response. In contrast, grasses with shallow root zones have minimal evapotranspiration rates, lower latent heat fluxes, and a rapid and sharp atmospheric temperature response. On the whole, converting a naturally wooded ecosystem to a farmland or pasture effectively decreases the available water in the subsurface for transpiration subsequently amplifying the atmospheric response to severe weather.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2013
- Bibcode:
- 2013AGUFM.H21M..07D
- Keywords:
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- 1843 HYDROLOGY Land/atmosphere interactions;
- 1847 HYDROLOGY Modeling;
- 3307 ATMOSPHERIC PROCESSES Boundary layer processes;
- 1834 HYDROLOGY Human impacts