%0 Journal Article
%T Multiple equilibria on planet Dune: climate¨Cvegetation dynamics on a sandy planet
%A Fabio Cresto Aleina
%A Mara Baudena
%A Fabio D'Andrea
%A Antonello Provenzale
%J Tellus B
%D 2013
%I Co-Action Publishing
%R 10.3402/tellusb.v65i0.17662
%X We study the interaction between climate and vegetation on an ideal water-limited planet, focussing on the influence of vegetation on the global water cycle. We introduce a simple mechanistic box model consisting in a two-layer representation of the atmosphere and a two-layer soil scheme. The model includes the dynamics of vegetation cover, and the main physical processes of energy and water exchange among the different components. With a realistic choice of parameters, this model displays three stable equilibria, depending on the initial conditions of soil water and vegetation cover. The system reaches a hot and dry state for low values of initial water content and/or vegetation cover, while we observe a wet, vegetated state with mild surface temperature when the system starts from larger initial values of both variables. The third state is a cold desert, where plants transfer enough water to the atmosphere to start a weaker, evaporation-dominated water cycle before they wilt. These results indicate that in this system vegetation plays a central role in transferring water from the soil to the atmosphere and trigger a hydrologic cycle. The model adopted here can also be used to conceptually illustrate processes and feedbacks affecting the water cycle in water-limited continental areas on Earth.
%K climate¨Cvegetation interactions
%K multiple stable states
%K water cycle
%K zero-dimensional models
%K evapotranspiration
%U http://www.tellusb.net/index.php/tellusb/article/view/17662/pdf_1