TY - JOUR
T1 - Airborne characterization of subsaturated aerosol hygroscopicity and dry refractive index from the surface to 6.5km during the SEAC4RS campaign
AU - Shingler, Taylor
AU - Crosbie, Ewan
AU - Ortega, Amber
AU - Shiraiwa, Manabu
AU - Zuend, Andreas
AU - Beyersdorf, Andreas
AU - Ziemba, Luke
AU - Anderson, Bruce
AU - Thornhill, Lee
AU - Perring, Anne E.
AU - Schwarz, Joshua P.
AU - Campazano-Jost, Pedro
AU - Day, Douglas A.
AU - Jimenez, Jose L.
AU - Hair, Johnathan W.
AU - Mikoviny, Tomas
AU - Wisthaler, Armin
AU - Sorooshian, Armin
N1 - Funding Information:
All data and results are available from the corresponding author (armin@email. arizona.edu). This research was funded by NASA grants NNX12AC10G and NNX14AP75G. The development of the DASH-SP instrument was funded by ONR grant N00014-10-1-0811. T.S. acknowledges support from a NASA Earth and Space Science Fellowship (NNX14AK79H). P.C.J., D.A.D., and J.L.J. were supported by NASA grants NNX12AC03G and NNX15AT96G. PTR-MS measurements during SEAC4RS were supported by the Austrian Federal Ministry for Transport, Innovation and Technology (bmvit) through the Austrian Space Applications Programme of the Austrian Research Promotion Agency (FFG). A.W. and T.M. received support from the Visiting Scientist Program at the National Institute of Aerospace.
Publisher Copyright:
© 2016. American Geophysical Union. All Rights Reserved.
PY - 2016
Y1 - 2016
N2 - In situ aerosol particle measurements were conducted during 21 NASA DC-8 flights in the Studies of Emissions and Atmospheric Composition, Clouds, and Climate Coupling by Regional Surveys field campaign over the United States, Canada, Pacific Ocean, and Gulf ofMexico. For the first time, this study reports rapid, size-resolved hygroscopic growth and real refractive index (RI at 532nm) data between the surface and upper troposphere in a variety of air masses including wildfires, agricultural fires, biogenic, marine, and urban outflow. The Differential Aerosol Sizing and Hygroscopicity Spectrometer Probe (DASH-SP) quantified size-resolved diameter growth factors (GF =Dp,wet/Dp,dry) that are used to infer the hygroscopicity parameter κ. Thermokinetic simulations were conducted to estimate the impact of partial particle volatilization within the DASH-SP across a range of sampling conditions. Analyses of GF and RI data as a function of air mass origin, dry size, and altitude are reported, in addition to κ values for the inorganic and organic fractions of aerosol. Average RI values are found to be fairly constant (1.52–1.54) for all air mass categories. An algorithm is used to compare size-resolved DASH-SP GF with bulk scattering f(RH= 80%) data obtained froma pair of nephelometers, and the results show that the two can only be reconciled if GF is assumed to decrease with increasing dry size above 400nm (i.e., beyond the upper bound of DASH-SP measurements). Individual case studies illustrate variations of hygroscopicity as a function of dry size, environmental conditions, altitude, and composition.
AB - In situ aerosol particle measurements were conducted during 21 NASA DC-8 flights in the Studies of Emissions and Atmospheric Composition, Clouds, and Climate Coupling by Regional Surveys field campaign over the United States, Canada, Pacific Ocean, and Gulf ofMexico. For the first time, this study reports rapid, size-resolved hygroscopic growth and real refractive index (RI at 532nm) data between the surface and upper troposphere in a variety of air masses including wildfires, agricultural fires, biogenic, marine, and urban outflow. The Differential Aerosol Sizing and Hygroscopicity Spectrometer Probe (DASH-SP) quantified size-resolved diameter growth factors (GF =Dp,wet/Dp,dry) that are used to infer the hygroscopicity parameter κ. Thermokinetic simulations were conducted to estimate the impact of partial particle volatilization within the DASH-SP across a range of sampling conditions. Analyses of GF and RI data as a function of air mass origin, dry size, and altitude are reported, in addition to κ values for the inorganic and organic fractions of aerosol. Average RI values are found to be fairly constant (1.52–1.54) for all air mass categories. An algorithm is used to compare size-resolved DASH-SP GF with bulk scattering f(RH= 80%) data obtained froma pair of nephelometers, and the results show that the two can only be reconciled if GF is assumed to decrease with increasing dry size above 400nm (i.e., beyond the upper bound of DASH-SP measurements). Individual case studies illustrate variations of hygroscopicity as a function of dry size, environmental conditions, altitude, and composition.
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U2 - 10.1002/2015JD024498
DO - 10.1002/2015JD024498
M3 - Article
AN - SCOPUS:84969981541
VL - 121
SP - 4188
EP - 4210
JO - Journal of Geophysical Research: Atmospheres
JF - Journal of Geophysical Research: Atmospheres
SN - 2169-897X
IS - 8
ER -