The Aerosol Module in the Community Radiative Transfer Model (v2.2 and v2.3): accounting for aerosol transmittance effects on the radiance observation operator

Details

• Journal Title:
  Geoscientific Model Development
• Personal Author:
  Lu, Cheng-Hsuan ; Liu, Quanhua ; Wei, Shih-Wei ; Johnson, Benjamin T. ; Dang, Cheng ; Stegmann, Patrick G. ; Grogan, Dustin ; Ge, Guoqing ; Hu, Ming ; Lueken, Michael
• NOAA Program & Office:
  CIRES (Cooperative Institute for Research in Environmental Sciences) ; NESDIS (National Environmental Satellite, Data, and Information Service) ; NCEI (National Centers for Environmental Information) ; OAR (Oceanic and Atmospheric Research) ; GSL (Global Systems Laboratory) ; NWS (National Weather Service) ; EMC (Environmental Modelling Center) ; NCEP (National Centers for Environmental Prediction)
• Description:
  The Community Radiative Transfer Model (CRTM), a sensor-based radiative transfer model, has been used within the Gridpoint Statistical Interpolation (GSI) system for directly assimilating radiances from infrared and microwave sensors. We conducted numerical experiments to illustrate how including aerosol radiative effects in CRTM calculations changes the GSI analysis. Compared to the default aerosol-blind calculations, the aerosol influences reduced simulated brightness temperature (BT) in thermal window channels, particularly over dust-dominant regions. A case study is presented, which illustrates how failing to correct for aerosol transmittance effects leads to errors in meteorological analyses that assimilate radiances from satellite infrared sensors. In particular, the case study shows that assimilating aerosol-affected BTs significantly affects analyzed temperatures in the lower atmosphere across several regions of the globe. Consequently, a fully cycled aerosol-aware experiment improves 1–5 d forecasts of wind, temperature, and geopotential height in the tropical troposphere and Northern Hemisphere stratosphere. Whilst both GSI and CRTM are well documented with online user guides, tutorials, and code repositories, this article is intended to provide a joined-up documentation for aerosol absorption and scattering calculations in the CRTM and GSI. It also provides guidance for prospective users of the CRTM aerosol option and GSI aerosol-aware radiance assimilation. Scientific aspects of aerosol-affected BT in atmospheric data assimilation are briefly discussed.
• Source:
  Geoscientific Model Development, 15(3), 1317-1329
• DOI:
  https://doi.org/10.5194/gmd-15-1317-2022
• ISSN:
  1991-9603
• Format:
  PDF
• Publisher:
  Copernicus GmbH
• Document Type:
  Journal Article
• Funding:
  Grant no. NA15NWS4680008
• License:
  https://creativecommons.org/licenses/by/4.0/
• Rights Information:
  CC BY
• Compliance:
  Submitted
• Main Document Checksum:
  urn:sha256:e20dde70522b93b4ebdf038bde01a5c5338e89040b5257f14b0697c5069d7703
• Download URL:
  https://repository.library.noaa.gov/view/noaa/51963/noaa_51963_DS1.pdf
• File Type:
  [PDF - 5.17 MB ]