R. T. Pinker, H. Wang, R. Hollmann, and H. Gadhavi

Department of Atmospheric and Oceanic Science, University of Maryland, College Park, Maryland

Use of SEVIRI cloud properties to simulate SW fluxes from GOES-R ABI

 

5th GOES Users' Conference, AMS 88, New Orleans, Jan 20-24, 2008

Objective Implement approach (2) with cloud properties from METEOSAT-8 SEVIRI observations to derive surface shortwave radiative fluxes. The cloud properties are produced under a reprocessing effort at EUMETSAT Satellite Application Facility on Climate Monitoring (CM-SAF) and are available hourly at 3 km spatial resolution for the full disk for about four months of 2004. Such data will also become available from the Advanced Baseline Imager (ABI) on GOES-R which has similar channels to those of SEVIRI. The product is evaluated against ground observations. For comparison, derived are also fluxes from METEOSAT–7 using method (1), that eventually, will be implemented also with METEOSAT-8.

Background Two types of methods are often used to derive radiative fluxes from

satellite observations:

1) Based on a relationship between the broadband reflected radiation at the top of the atmosphere (TOA) and atmospheric transmittance. Once the atmospheric transmittance is known, the surface irradiance can be computed from the incoming solar flux at the TOA and auxiliary information on the state of the atmosphere and the surface.

2) Based on independently derived atmospheric optical parameters (aerosol optical depth and cloud optical depth and phase) from multi-channel observations.

Data Sources

Cloud optical properties: Retrieved from the Spinning Enhanced Visible and Infrared Imager (SEVIRI) on board the Meteosat Second Generation (METEOSAT−8) in the Satellite Application Facility on Climate Monitoring (CM-SAF), 3 km resolution at nadir, provided at 45 minute after every hour.

Precipitable water: NCEP reanalysis

Aerosol Optical Depth: Multi-angle Imaging SpectroRadiometer (MISR) daily Component Global Aerosol Product (CGSA) at 0.5 degree resolution

Total Ozone Amount: MODIS monthly products at 1 degree resolution

Spectral surface albedo: The Filled Land Surface Albedo Product from MODIS/TERRA Product at a 0.05 degrees resolution.

Cloud properties from CM-SAF at 3 km resolution are re-gridded into 0.125 degree boxes extending from 75 W to 75 E and 60 S to 60 N to derive shortwave radiative fluxes for July of 2004.

Summary Surface radiative fluxes are estimated with cloud properties from METEOSAT-8 provided by EUMETSAT CM-SAF SEVIRI observations.

Similar information will become available from ABI on GOES-R.

Of interest is evaluation of the radiative flux estimates against ground observations and independent satellite products.

Will help to develop guidelines for optimal utilization of ABI information (Model (1) or (2) approach?).

Will facilitate evaluation of cloud products from ABI.

SEVIRI METEOSAT-8 METEOSAT-7

met8 met7

All six BSRN sites, July, 2004, Meteosat-8

Instantaneous flux Daily flux

Three BSRN sites (SBO, TEAM an DAA), July, 2004Instantaneous flux

Meteosat-8 Meteosat-7

1245Z, Jul 6, 2004 1300Z, Jul 6, 2004

Shortwave radiative fluxes at 0.125 degree resolution

Daily Flux, July 6, 2004

Monthly Flux July 2004

Input Parameters to Inference Scheme (2)

The inference scheme to derive surface radiative fluxes from independently derived optical properties of clouds and aerosols has been previously developed at the University of Maryland (2). It requires: column water vapor, column ozone amount, cloud fraction, cloud optical depth, aerosol optical depth and spectral surface albedo.

Station Name  Abbrev.  Sponsor

Camborne  CAM  Great Britain

Palaiseau Cedex  PAL  France

Payerne  PAY  Switzerland

Sede Boqer  SBO  Israel

Tamanrasset  TAM  Algerie

De Aar  DAA  South Africa

BSRN site location BSRN site list

Evaluation

Validation sites

Acknowledgement: This work is supported under the Cooperative Institute for Climate Studies Cooperative Agreement, NOAA Award number NA17EC1483.