ICARTT 2004

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ICARTT 2004 Ronald H. Brown Measurements
Relevant to Aerosol Direct Radiative
Forcing
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Regional Assessment of Aerosol Direct Radiative
Forcing - MEASUREMENTS
CATEGORY Measured Parameters Platform
Aerosol Chemical Composition Anions and cations Elemental carbon (EC) Organic carbon (OC) Organic carbon (speciated) Trace elements RHB, P3, CP RHB RHB, P3, CP RHB, CP RHB
Aerosol Physical and Optical Properties Number vs size, accumulation coarse modes Absorption (450, 550, 700 nm) Scattering backscattering (450, 550, 700 nm) f(RH) Lidar backscatter profiles RHB, P3 RHB, P3, CP RHB, P3, CP RHB, P3 RHB, NOAA-RS, CP
Radiative Properties Aerosol Optical Depth (spectral) Radiative fluxes, solar and longwave, upwelling and downwelling (spectral) Direct, diffuse, and total irradiances (spectral where possible) Surface albedo RHB, NASA-RS, MISR NASA-RS, MISR P3, NASA-RS NASA-RS

Meteorological Parameters Wind speed, direction, RH, T, pressure, cloud type and amount, visibility RHB
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• Measurements Sub-1 mm particles
• Cavity Ring Down Extinction Cell
• Aerosol extinction f(RH) (66 / 30) continuous
• plus humidity scans
• Humidograph
• Aerosol scattering f(RH)
• humidity scans (increasing and decreasing RH)
• between 35 and 90 RH
• Aerosol composition
• Aerodyne Mass Spectrometer, PILS, impactors
• SO4, NO3-, NH4, POM, EC, Trace elements

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Comparison of Hygroscopic Growth Dependence of
Aerosol Scattering from Humidified Nephelometer
and Extinction from CRD DOY 203 (1200 UTC)
f(RH)
f(RH)
RH
RH
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Dependence of f(RH) on aerosol composition
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Comparison of Extinction Measured by Cavity
Ring-down Extinction Cell and OPAL (LIDAR) at ?
355 nm
Ambient RH 80 to 90
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Comparison of 3 Microtops Units for 380, 500,
675, 870 nm
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Comparison of 2 Microtops Units for 440 nm
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RHB Spatial Distribution of AOD measurements
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RHB Time Series of Sub-10 um Scattering and AOD
J31 Overflights
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RHB Time Series of Sub-10 um Scattering and AOD
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Time series of AOD and spectral slope
Regions of higher AOD Polluted, more small
particles stronger spectral dependence
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Wang et al., JGR, 2003. Used shipboard AOD
measurements to determine the accuracy of AOD
retrievals from the GMS5 geostationary
satellite.
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Markowicz et al., JGR, 2003. Used shipboard
f(RH) measurements to estimate the dependence of
Surface and top of atmosphere forcing on RH.
Diurnally averaged aerosol forcing efficiencies
determine from a radiative transfer model as a
function of RH.
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Contacts f(RH) Tahllee Baynard,
tbaynard_at_al.noaa.gov Wei Wang,
weiwang_at_uiuc.edu Scattering, backscattering,
absorption Trish Quinn, patricia.k.quinn_at_no
aa.gov Also available at http//saga.pmel.noaa.go
v/data AOD Trish Quinn, patricia.k.quinn_at_noaa.go
v Also available at http//saga.pmel.noaa.gov/da
ta