HR: 1340h
AN: A43C-1414    [Abstracts]
TI: Urban aerosol effects on surface insolation and surface temperature
AU: * Jin, M
EM: mjin@atmos.umd.edu
AF: University of Maryland, College Park, Department of Atmospheric and Oceanic Science, College Park, MD 20752, United States
AU: Burian, S J
EM: burian@eng.utah.edu
AF: AU: Remer, L A
EM: Lorraine.A.Remer@nasa.gov
AF: NASA Goddard Space Flight Center, Bldg 33 Room A313 NASA Goddard Space Flight Center, Greenbelt, MD 20771, United States
AU: Shepherd, M J
EM: marshgeo@uga.edu
AF: The University of Georgia, Department of Geography, Atmospheric Sciences Program The University of Georgia, Athens, Geo 30602, United States
AB: Urban aerosol particulates may play a fundamental role in urban microclimates and city-generated mesoscale circulations via its effects on energy balance of the surface. Key questions that need to be addressed include: (1) How do these particles affect the amount of solar energy reaching the surface and resulting surface temperature? (2) Is the effect the same in all cities? and (3) How does it vary from city to city? Using NASA AERONET in-situ observations, a radiative transfer model, and a regional climate mode (MM5), we assess aerosol effects on surface insolation and surf ace temperature for dense urban-polluted regions. Two big cities, one in a developing country (Beijing, P.R. China) and another in developed country (New York City, USA), are selected for inter-comparison. The study reveals that aerosol effects on surface temperature depends largely on aerosols' optical and chemical properties as well as atmosphere and land surface conditions, such as humidity and land cover. Therefore, the actual magnitudes of aerosol effects differ from city to city. Aerosol measurements from AERONET show both average and extreme cases for aerosol impacts on surface insolation. In general, aerosols reduce surface insolation by 30Wm-2. Nevertheless, in extreme cases, such reduction can exceed 100 Wm-2. Consequently, this reduces surface skin temperature 2-10C in an urban environment.
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 0480 Remote sensing
DE: 0493 Urban systems
DE: 1615 Biogeochemical cycles, processes, and modeling (0412, 0414, 0793, 4805, 4912)
DE: 1631 Land/atmosphere interactions (1218, 1843, 3322)
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting