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Temperature Response to Land Cover Changes on the Tibetan Plateau Oliver W. Frauenfeld and Tingjun Zhang The Tibetan Plateau, with an average elevation of >4000 m and approximately the size of Texas, is a semi-arid environment, both moisture and temperature limited, and is occupied by montane grass- and shrublands. Over 62% of the plateau is used for agriculture: farmlands, forests, and a majority (80%) is used for livestock grazing. Since the early-late 1950s, and accelerated since the 1980s, significant urban expansion and changes in agricultural and industrial practices have shaped this part of the world. Originally a mostly rural (pastoral) region, conscious efforts to urbanize the plateau and analogous socio-economic changes have resulted in a substantially altered landscape. Because of the plateau's role in the Asian Monsoon system, the water resources of most of the Asian continent and therefore the livelihoods of over 3.7 billion people, the extensive land cover/land use changes in this part of the world are arguably of heightened importance to local-global resources and the climate system. We hypothesize that as socio-economic changes have caused a net reduction in vegetation, this has resulted in significantly reduced soil moisture which feeds back to further decrease vegetation, but also increase sensible (versus latent) heat fluxes, and hence increase temperatures. Our related work has already demonstrated that, indeed, reported warming on the Tibetan Plateau seems to be confined to low-lying populated regions. In this present analysis we categorize in situ temperature observations by both land cover type and disturbed versus undisturbed regions, and quantify the corresponding warming trends related to land cover changes. |