01753nas a2200181   4500008004100000022001400041245009000055210006900145260007900214300001100293490000700304520106600311100002101377700002001398700001801418700001401436856012101450       2008                        eng d  a0094-827600aObservations of enhanced aerosol longwave radiative forcing over an urban environment0 aObservations of enhanced aerosol longwave radiative forcing over  a2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USAbAMER GEOPHYSICAL UNIONcFEB  aL048170 v353 a<p>Collocated measurements of sun/ sky radiance, aerosol chemical composition and radiative fluxes have been utilized to estimate longwave aerosol radiative forcing over Pune, an Indian urban site during dry winter [Dec2004 to Feb2005] by two methods. Hybrid method which uses observed downwelling and modeled upwelling longwave fluxes for different aerosol loadings yielded a surface forcing of 9.4 Wm(-2). Model approach includes utilization of skyradiometer derived spectral aerosol optical properties in the visible and near infra-red wavelengths, modeled aerosol properties in 1.2-40 mu m using observed soot and chemical composition data, MODIS water vapor and TOMS column ozone in a radiative transfer model. Estimates from model method showed longwave enhancement of 6.5 and 8.2Wm(-2) at the surface with tropical model atmosphere and temporally varying profiles of temperature and humidity, respectively. Study reveals that about 25% of the aerosol shortwave cooling is being compensated by increase in longwave radiation due to aerosol absorption.</p>1 aPanicker, A., S.1 aPandithurai, G.1 aSafai, P., D.1 aKewat, S.  uhttps://library.ncl.res.in/content/observations-enhanced-aerosol-longwave-radiative-forcing-over-urban-environment-0