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International MODIS/AIRS Processing Package

 University of Wisconsin-Madison AIRS Dual Regression Single FOV Retrieval Package Version 3.0

 3 November 2011

  This package is a stand alone AIRS single Field-of-View (FOV) retrieval software update to the retrieval code that was included as part of the UW AIRS Utility Package released in December 2009. This update to the retrieval algorithm is a dual regression technique that uses training data to separately determine clear and cloudy solutions, and combines the retrievals after determining a cloud top where the profiles start to diverge from each other. If the differences between the clear and cloudy profiles stay small, the clear trained solution makes up the final result. This is a stand alone retrieval algorithm that no longer requires the MODIS cloud mask as input. This technique was developed by Dr. Elisabeth Weisz and Dr. William Smith, University of Wisconsin-Madison, Space Science and Engineering Center (SSEC).

The software creates single FOV products from input direct broadcast or archived AIRS L1B radiance files:
  • atmospheric temperature [K] at 101 pressure levels
  • atmospheric moisture [g/kg] at 101 pressure levels
  • atmospheric ozone [ppmv] at 101 pressure levels
  • atmospheric relative humidity [%] at 101 pressure levels
  • atmospheric dew point temperature [K] at 101 pressure levels
  • surface skin temperature [K]
  • surface emissivity at 2378 (AIRS) wavenumbers
  • total precipitable water [cm]
  • precipitable water 1 (vertically integrated from 900 hPa to surface) [cm]
  • precipitable water 2 (vertically integrated from 700 to 900 hPa) [cm]
  • precipitable water 3 (vertically integrated from 300 to 700 hPa) [cm]
  • total ozone amount (vertically integrated) [dobson units]
  • lifted index [deg celsius]
  • convective available potential energy [J/kg]
  • CO2 amount [ppmv]
  • cloud top pressure 1 [hPa]
  • cloud top pressure 2 [hPa] (Upper level cirrus cloud tops only)
  • cloud top temperature 1 [K]
  • cloud top temperature 2 [K] (Upper level cirrus cloud tops only)
  • cloud optical thickness
  • cloud mask (values: 0 clear, 1 cloud)
In addition to the parameters above the output file contains:
  • latitude [degrees]
  • longitude [degrees]
  • surface pressure (gdas values interpolated to AIRS grid) [hPa]
  • quality flag1
  • quality flag2
  • quality flag3

More information is provided in the release README file that is included with the package.


A new version of this software has been released. Please check the Release History page by selecting the History link along the Top Navigation Bar, to find the the most recent version.