CCMA1: Cities inside climate models & downscaling methods Towards understanding the hydro-climatic implications of urbanization in the GFDL global climate and earth system modeling framework Dan Li 1, Sergey Malyshev 2, Elena Shevliakova 2, Shian-Jiann Lin 3 Program of Atmospheric and Oceanic Sciences, Princeton University, Princeton, NJ 08544, USA; 2Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544, USA; 3NOAA/Geophysical Fluid Dynamics Laboratory, Princeton, NJ 08544, USA;
[email protected] The environmental significance of land-use/land-cover changes, of which urbanization is an extreme case, is well recognized but understood in a limited way. How urbanization affects regional and global climate and how urban areas respond to climate change at time scales from seasonal to decadal are critical areas of research. However, to date, most global climate models that are used to investigate impacts of land-use/land-cover changes on the climate do not include an urban representation. Moreover, the effect of urban expansion on climate of near-by areas has not been characterized in any existing urban representations. In order to answer these questions, the Geophysical Fluid Dynamics Laboratory (GFDL) is developing a high-resolution global climate model with an urban representation that can simulate interactively both changes in urban environments and feedbacks of urban changes. In this study, efforts towards urbanizing the GFDL land model LM3 are described. Historical simulations with the urbanized GFDL LM3 are presented to demonstrate how growth of urban areas has affected the near-surface climate in recent decades over the continental United States. Changes of temperature and humidity in areas of city sprawl under climate change conditions Daniel Argueso 1,2 , Jason P.