Search Results
et al. 2009 ; Parding et al. 2011 ; Miller et al. 2012 ; Collow et al. 2016a ). These studies have produced either heating rate profiles or “bulk” measurements of the net radiative heating of the column, using the vertical cross-atmosphere radiative flux divergence (RFD). The RFD is presented in watts per meter squared and is defined so that net fluxes at the surface and the top of the atmosphere (TOA) are a positive quantity when there is net radiation transfer into the column. This sign
et al. 2009 ; Parding et al. 2011 ; Miller et al. 2012 ; Collow et al. 2016a ). These studies have produced either heating rate profiles or “bulk” measurements of the net radiative heating of the column, using the vertical cross-atmosphere radiative flux divergence (RFD). The RFD is presented in watts per meter squared and is defined so that net fluxes at the surface and the top of the atmosphere (TOA) are a positive quantity when there is net radiation transfer into the column. This sign
assumed among the groups. Broadband radiative transfer is then computed using Chou and Suarez (1999) for the shortwave fluxes and Chou et al. (2001) for the longwave. Additional details about the MERRA system can be found in Rienecker et al. (2008 , 2011 ). All two-dimensional fields, such as cloud-top pressure and TOA and surface radiative fluxes, are available hourly on the native 0.5° × 0.66° grid. b. MERRA-2 The differences between the atmospheric global climate models underlying MERRA and
assumed among the groups. Broadband radiative transfer is then computed using Chou and Suarez (1999) for the shortwave fluxes and Chou et al. (2001) for the longwave. Additional details about the MERRA system can be found in Rienecker et al. (2008 , 2011 ). All two-dimensional fields, such as cloud-top pressure and TOA and surface radiative fluxes, are available hourly on the native 0.5° × 0.66° grid. b. MERRA-2 The differences between the atmospheric global climate models underlying MERRA and
, carbonaceous aerosols, and sulfate-based aerosols). Buchard et al. (2015) developed a radiative transfer interface to the Vector Linearized Discrete Ordinate Radiative Transfer (VLIDORT) radiative transfer code ( Spurr 2006 ) to simulate the UV AI from the GEOS-5 aerosol fields at the OMI footprint. Simulated AI can then be directly compared with AI derived from the OMI instrument. The simulated AI is computed as where is the VLIDORT-calculated TOA radiance at 354 nm using MERRA-2 simulated aerosol
, carbonaceous aerosols, and sulfate-based aerosols). Buchard et al. (2015) developed a radiative transfer interface to the Vector Linearized Discrete Ordinate Radiative Transfer (VLIDORT) radiative transfer code ( Spurr 2006 ) to simulate the UV AI from the GEOS-5 aerosol fields at the OMI footprint. Simulated AI can then be directly compared with AI derived from the OMI instrument. The simulated AI is computed as where is the VLIDORT-calculated TOA radiance at 354 nm using MERRA-2 simulated aerosol
. [Available online at https://gmao.gsfc.nasa.gov/reanalysis/MERRA-2/docs/ .] Meng , Z. , P. Yang , G. W. Kattawar , L. Bi , K. N. Liou , and I. Laszlo , 2010 : Single-scattering properties of tri-axial ellipsoidal mineral dust aerosols: A database for application to radiative transfer calculations . J. Aerosol Sci. , 41 , 501 – 512 , doi: 10.1016/j.jaerosci.2010.02.008 . 10.1016/j.jaerosci.2010.02.008 Molod , A. , L. L. Takacs , M. J. Suarez , J. Bacmeister , I.-S. Song
. [Available online at https://gmao.gsfc.nasa.gov/reanalysis/MERRA-2/docs/ .] Meng , Z. , P. Yang , G. W. Kattawar , L. Bi , K. N. Liou , and I. Laszlo , 2010 : Single-scattering properties of tri-axial ellipsoidal mineral dust aerosols: A database for application to radiative transfer calculations . J. Aerosol Sci. , 41 , 501 – 512 , doi: 10.1016/j.jaerosci.2010.02.008 . 10.1016/j.jaerosci.2010.02.008 Molod , A. , L. L. Takacs , M. J. Suarez , J. Bacmeister , I.-S. Song
from the SBUV also differs, with MERRA-2 assimilating version 8.6 on 21 layers from 1980 through 2004 before switching to OMI and MLS in October 2004. In contrast, MERRA used SBUV version 8 throughout, in a form degraded from its original 21 layers to 12. d. Radiance assimilation Radiative transfer calculations necessary for the assimilation of satellite radiances in MERRA-2 are performed using the CRTM ( Han et al. 2006 ; Chen et al. 2008 ). MERRA-2 uses version 2.1.3 of the CRTM for assimilation
from the SBUV also differs, with MERRA-2 assimilating version 8.6 on 21 layers from 1980 through 2004 before switching to OMI and MLS in October 2004. In contrast, MERRA used SBUV version 8 throughout, in a form degraded from its original 21 layers to 12. d. Radiance assimilation Radiative transfer calculations necessary for the assimilation of satellite radiances in MERRA-2 are performed using the CRTM ( Han et al. 2006 ; Chen et al. 2008 ). MERRA-2 uses version 2.1.3 of the CRTM for assimilation
Interferometer (IASI; starting in September 2008), the Cross-Track Infrared Sounder (on the Suomi NPP satellite, from April 2012 onward), and Advanced Technology Microwave Sounder (on Suomi NPP , starting in November 2011) in addition to those already used in MERRA. Radiance data from the Stratospheric Sounding Unit instruments are used in both reanalyses, but in MERRA-2 these observations are assimilated with the more advanced Community Radiative Transfer Model, the same as for all other radiance data
Interferometer (IASI; starting in September 2008), the Cross-Track Infrared Sounder (on the Suomi NPP satellite, from April 2012 onward), and Advanced Technology Microwave Sounder (on Suomi NPP , starting in November 2011) in addition to those already used in MERRA. Radiance data from the Stratospheric Sounding Unit instruments are used in both reanalyses, but in MERRA-2 these observations are assimilated with the more advanced Community Radiative Transfer Model, the same as for all other radiance data
least 10 data points to estimate each statistic for a given grid cell. Even with this screening, the gridded output will be much less certain when/where station coverage is less dense, which occurs over Africa, South America, central Australia, and the high latitudes. 4) CERES-EBAF radiation data CERES-EBAF version 4.00 surface radiances are produced with a radiative transfer model after adjusting modeled and observed input data for consistency with top-of-atmosphere (TOA) CERES-EBAF radiation
least 10 data points to estimate each statistic for a given grid cell. Even with this screening, the gridded output will be much less certain when/where station coverage is less dense, which occurs over Africa, South America, central Australia, and the high latitudes. 4) CERES-EBAF radiation data CERES-EBAF version 4.00 surface radiances are produced with a radiative transfer model after adjusting modeled and observed input data for consistency with top-of-atmosphere (TOA) CERES-EBAF radiation
