HR: 0800h
AN: A51B-08    [Abstracts]
TI: Spectral Measurements of Aerosol Absorption from UV to VISIBLE
AU: * Krotkov, N A
EM: krotkov@mhatter.gsfc.nasa.gov
AF: Goddard Earth Sciences and technology Center University of Maryland Baltimore County, NASA Goddard Space Flight Center, code 613.3, Greenbelt, MD 20771, United States
AU: Labow, G
EM: labow@qhearts.gsfc.nasa.gov
AF: Science Systems and Applications, Inc, 10210 Greenbelt Rd., Suite 400, Lanham, MD 20706, United States
AU: Herman, J
EM: herman@tparty.gsfc.nasa.gov
AF: NASA Goddard Space Flight Center, 8800 Greenbelt Rd, Greenbelt, MD 20771, United States
AU: Bhartia, P K
EM: Pawan.Bhartia@nasa.gov
AF: NASA Goddard Space Flight Center, 8800 Greenbelt Rd, Greenbelt, MD 20771, United States
AU: Slusser, J
EM: sluss@nrel.colostate.edu
AF: USDA UVB Radiation Monitoring Program, Natural Resource Ecology Laboratory Colorado State University, University St # 133 , Fort Collins, CO 80523-1499, United States
AU: Durham, B
EM: william.durham@colostate.edu
AF: USDA UVB Radiation Monitoring Program, Natural Resource Ecology Laboratory Colorado State University, University St # 133 , Fort Collins, CO 80523-1499, United States
AU: Janson, G
EM: george.janson@colostate.edu
AF: USDA UVB Radiation Monitoring Program, Natural Resource Ecology Laboratory Colorado State University, University St # 133 , Fort Collins, CO 80523-1499, United States
AU: Wilson, C
EM: Charles.M.Wilson@noaa.gov
AF: Central UV Calibration Facility, NOAA R/ARL, 325 Broadway, Boulder, CO 80305, United States
AU: Disterhoft, P
EM: Patrick.Disterhoft@noaa.gov
AF: Central UV Calibration Facility, NOAA R/ARL, 325 Broadway, Boulder, CO 80305, United States
AU: Cede, A
EM: cede@mhatter.gsfc.nasa.gov
AF: Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD 20742-2465, United States
AU: Abuhassan, N
EM: nader@ventus.gsfc.nasa.gov
AF: Science Systems and Applications, Inc, 10210 Greenbelt Rd., Suite 400, Lanham, MD 20706, United States
AU: Eck, T F
EM: teck@ltpmail.gsfc.nasa.gov
AF: Goddard Earth Sciences and technology Center University of Maryland Baltimore County, NASA Goddard Space Flight Center, code 613.3, Greenbelt, MD 20771, United States
AU: Holben, B
EM: brent@aeronet.gsfc.nasa.gov
AF: NASA Goddard Space Flight Center, 8800 Greenbelt Rd, Greenbelt, MD 20771, United States
AU: Bais, A
EM: abais@auth.gr
AF: Aristotle University of Thessaloniki, p.O. Box 54124, Thessaloniki, GR-54124, Greece
AU: Rapsomanikis, S
EM: rapso@env.duth.gr
AF: Laboratory of Atmospheric Pollution and Control Engineering of Atmospheric Pollutants, Faculty of Engineering Department of Environmental Engineering Democritus University of Thrace, , P.O. Box 447 , Xanthi, 67100, Greece
AB: Amount of solar radiation reaching the Earth's surface can be strongly influenced by aerosol absorption. The aerosol absorption optical thickness (AAOT) in the visible and near IR (440 nm- 1020nm) is routinely produced from almucantar measurements made by the CIMEL instruments in the AERONET network. AAOT in the UV (300nm- 368nm) have been derived from the total and diffuse hemispherical flux measurements made by UV- Multifilter Rotating Shadowband Radiometer (UV-MFRSR, Yankee Environmental Systems, Inc.) instruments. However, no direct comparisons between these two methods exist because the CIMEL wavelengths (used in almucantar retrievals) do not overlap with the UV-MFRSR wavelengths. To enable direct comparisons between the two techniques, we have modified our UV-MFRSR, part of USDA UVB Monitoring and Research Network, by replacing standard 300nm filter with 440nm filter used in AERONET network. The instrument has been deployed at Mauna Loa Observatory, at NASA GSFC in Greenbelt, MD (July 2005 - June 2006) and during SCOUT-03 field campaign in Thessaloniki, Greece in July 2006. During these deployments the instrument's calibration was monitored daily using co-located AERONET and BREWER direct sun measurements of aerosol extinction optical thickness (AOT). Between the deployments the instrument was thoroughly calibrated at the NOAA Central UV Calibration Facility in Boulder, Colorado. We find that the UV-MSFRSR instrument is highly susceptible to calibration drifts. However, these drifts can be accurately assessed using AERONET and BREWER direct sun data. After correcting for these calibration changes, the AAOT was inferred by fitting the measurements of global and diffuse atmospheric transmittances with the forward RT model independently at each spectral channel. The AOT data and ancillary measurements of aerosol column particle size distribution and refractive index in the visible wavelengths (by CIMEL sun-sky almucantar inversions), direct -sun column NO2 and ozone (by Brewer mk III spectrometer), surface pressure and albedo constrained the forward radiative transfer model input. Derived AAOT and SSA at 440nm were inter- compared with AERONET almucantar inversions at the same wavelength and with Brewer SSA measurements at 340nm during SCOUT-03 campaign. These measurements constitute the first continuous UV-VIS spectra of AAOT and SSA at two different locations in Maryland, USA and Thessaloniki, Greece.
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 0345 Pollution: urban and regional (0305, 0478, 4251)
DE: 4801 Aerosols (0305, 4906)
DE: 4906 Aerosols (0305, 4801)
SC: Atmospheric Sciences [A]
MN: 2007 Joint Assembly