All‐sky aerosol direct radiative effects at the ARM SGP site

Details

• Journal Title:
  Journal of Geophysical Research: Atmospheres
• Personal Author:
  Balmes, Kelly A. ; Fu, Qiang
• NOAA Program & Office:
  OAR (Oceanic and Atmospheric Research) ; GML (Global Monitoring Laboratory) ; CIRES (Cooperative Institute for Research in Environmental Sciences)
• Description:
  All-sky aerosol direct radiative effect (DRE) was estimated for the first time at the Atmospheric Radiation Measurement Southern Great Plains site using multiyear ground-based observations. The NASA Langley Fu-Liou radiation model was employed. Observed inputs for the radiation model include aerosol and cloud vertical extinction profile from Raman lidar; spectral aerosol optical depth, single-scattering albedo, and asymmetry factor from Aerosol Robotic Network; cloud water content profiles from radars; temperature and water vapor profiles from radiosondes; and surface shortwave spectral albedo from radiometers. A cloudy-sky radiative closure experiment was performed. The relative mean differences between modeled and observed surface downwelling shortwave total fluxes were 6% (7%) for transparent (opaque) cloudy-skies. The estimated annual mean all-sky aerosol DRE is −2.13urn:x-wiley:2169897X:media:jgrd57247:jgrd57247-math-00010.54 W m−2 at the top of atmosphere (TOA) and −5.95urn:x-wiley:2169897X:media:jgrd57247:jgrd57247-math-00020.87 W m−2 at the surface, compared to −3.00urn:x-wiley:2169897X:media:jgrd57247:jgrd57247-math-00030.58 W m−2 and −6.85urn:x-wiley:2169897X:media:jgrd57247:jgrd57247-math-00041.00 W m−2, respectively, under clear-sky conditions. The seasonal cycle of all-sky aerosol DRE is similar to that of the clear-sky, except with secondary influences of the clouds: The cloud radiative effect is strongest (most negative) in the spring, which reduces the all-sky aerosol DRE. The relative uncertainties in all-sky aerosol DRE due to measurement errors are generally comparable to those in clear-sky conditions except for the aerosol single-scattering albedo. The TOA all-sky aerosol DRE relative uncertainty due to aerosol single-scattering albedo uncertainty is larger than that in clear-sky, leading to a larger total relative uncertainty. The measurement errors in cloud properties have small effects on the all-sky aerosol DRE.
• Keywords:
  Aerosols
• Source:
  Journal of Geophysical Research: Atmospheres, 126, e2021JD034933
• DOI:
  https://doi.org/10.1029/2021JD034933
• Document Type:
  Journal Article
• Rights Information:
  Other
• Compliance:
  Submitted
• Main Document Checksum:
  urn:sha256:01d0ca61e623a32055ee51c1cbd6ff80a83c2b3b159f85596381b85d2d60f824
• Download URL:
  https://repository.library.noaa.gov/view/noaa/44764/noaa_44764_DS1.pdf
• File Type:
  [PDF - 2.91 MB ]