2005 BES Annual Meeting Presentation and Poster Abstracts

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Spatial Differences in Air Temperatures in and Near Baltimore, MD
 
Gordon Heisler, Baohua Tao, Jeffrey Walton, Richard Grant, Richard Pouyat, Ian Yesilonis, Andrea Taylorson, David Schindler, David Nowak, and Ken Belt
 
Abstract: As part of the Baltimore Ecosystem Study, we are measuring weather variables at five sites near Baltimore, MD. In addition, data are available from two National Weather Service Automated Surface Observation Stations (ASOS) sites. The measurements include temperature at the 1.5-meter height at all stations. Our sites include one in an open pasture, a nearby woodlot, a residential area with heavy tree cover but few buildings, a lawn area with nearby trees near a large apartment complex, and a residential area with some trees and large lawn areas. The ASOS sites are in downtown Baltimore and at the Baltimore/Washington International Airport (BWI), about 5.6 km south. Our sites are about 6 km NW of downtown (2 stations) and 7.5 km NE of downtown (3 stations). Temperature differences on an hourly basis between each site and the downtown ASOS site are being related empirically by regression analysis to upwind tree, impervious, and water land cover from the National Land Cover Data (NLCD) 2001 database. Additional predictor variables for temperature difference are atmospheric stability (Turner Class, derived from BWI cloud and wind speed data), vapor pressure deficit, antecedent precipitation, sky view and transmitted direct beam solar radiation estimated from hemispherical photographs at each site, and Patapsco River water temperature. The initial analysis is for May through September 2004. During this period, the downtown site was generally warmer than the other sites, with the temperature difference between the downtown and more rural sites being as large as 12ºC and commonly 8ºC.