Authors: Tianna Bogart*, Frostburg State University
Topics: Climatology and Meteorology, Land Use and Land Cover Change
Keywords: Climate, Urban Climate, Climate Modeling, GCM, land-atmosphere interaction
Session Type: Poster
Start / End Time: 10:00 AM / 11:40 AM
Room: Napoleon Foyer/Common St. Corridor, Sheraton, 3rd Floor
Presentation File: No File Uploaded
Given the incorporation of the urban land unit within the last few versions of global climate models, many more facets of the urban-climate relationship remain to be investigated. By comparing thirty-year ensembles of an atmospheric model coupled with a land model, both with and without the inclusion of the urban land type, the sensitivity of energy budget pathways and influences within the atmospheric model to is assessed. As expected, largest differences tend to be in the Northern Hemisphere near the globe's most expansive and dense cities. Seasonality to the urban influence also exists, with the transition seasons, especially the months of September, October, and November, with larger temperature differences.
Although the urban land type is a sub-grid phenomena that rarely occupies more than half of a grid cell at the nominal 1x1-degree resolution used here, significant changes in basic climate variables are present in some regions. Seasonal differences in solar radiation flux towards the surface and towards the top of the atmosphere were analyzed to determine the nature of simulated temperature changes. The alignment of significant solar flux changes, in both directions, suggests that surface albedo alone is not responsible for changes in temperature. In addition, by considering the large areas of change longwave flux at the surface, prevalent in all seasons, there is a clear, yet complex, relationship between the altered presence of clouds and their influence on the surface energy budget due to the incorporation of the urban land unit into the model.