Influence of Common Assumptions Regarding Aerosol Composition and Mixing State on Predicted CCN Concentration

Details

• Journal Title:
  Atmosphere
• Personal Author:
  Mahish, Manasi ; Jefferson, Anne ; Collins, Don
• NOAA Program & Office:
  OAR (Oceanic and Atmospheric Research) ; ESRL (Earth System Research Laboratory) ; CIRES (Cooperative Institute for Research in Environmental Sciences)
• Description:
  A 4-year record of aerosol size and hygroscopic growth factor distributions measured at the Department of Energy's Southern Great Plains (SGP) site in Oklahoma, U.S. were used to estimate supersaturation (S)-dependent cloud condensation nuclei concentrations (N-CCN). Baseline or reference N-CCN(S) spectra were estimated using -Kohler Theory without any averaging of the measured distributions by creating matrices of size- and hygroscopicity-dependent number concentration (N) and then integrating for S > critical supersaturation (S-c) calculated for the same size and hygroscopicity pairs. Those estimates were first compared with directly measured N-CCN at the same site. Subsequently, N-CCN was calculated using the same dataset but with an array of simplified treatments in which the aerosol was assumed to be either an internal or an external mixture and the hygroscopicity either assumed or based on averages derived from the growth factor distributions. The CCN spectra calculated using the simplified treatments were compared with those calculated using the baseline approach to evaluate the error introduced with commonly used approximations.
• Source:
  Atmosphere, 9(2), 18.
• DOI:
  https://doi.org/10.3390/atmos9020054
• Document Type:
  Journal Article
• Rights Information:
  CC BY
• Compliance:
  Submitted
• Main Document Checksum:
  urn:sha256:7aa54d4f944a902fbcd2971bccacec18693a7e8bc28823b73727e2f970eaecf3
• Download URL:
  https://repository.library.noaa.gov/view/noaa/21727/noaa_21727_DS1.pdf
• File Type:
  [PDF - 5.19 MB ]