A database of spectral surface reflectivity in the range 335–772 nm derived from 5.5 years of GOME observations

Abstract

A global database of Lambert‐equivalent reflectivity (LER) of the Earth's surface has been constructed by analyzing observations of the reflectivity at the top of the atmosphere made by the Global Ozone Monitoring Experiment (GOME). Since its launch on board the ERS‐2 satellite in April 1995, the GOME instrument has been measuring spectra of the Earth between 237 and 794 nm, with a spectral resolution between 0.2 and 0.4 nm and a spatial resolution between 40 × 80 and 40 × 320 km2. The LER database covers eleven 1‐nm‐wide wavelength bins centered at 335, 380, 416, 440, 463, 494.5, 555, 610, 670, 758, and 772 nm, which were selected for various retrieval applications. The database has a spatial resolution of 1° × 1°, is made for each month of the year, and pertains to the period June 1995–December 2000. Typical spectra of various surface types are presented. Attention is paid to instrument degradation and residual cloud contamination. We have found satisfactory agreement between our database at 380 nm and the Total Ozone Mapping Spectrometer (TOMS) LER database at 340–380 nm, with negligible average difference and a standard deviation of 0.013. The database presented here can be used to improve retrievals of trace gases, clouds and aerosols from GOME, Scanning Imaging Absorption Spectrometer or Atmospheric Cartography (SCIAMACHY), Ozone Monitoring Instrument (OMI), and GOME‐2.

Spatially Refined Aerosol Direct Radiative Forcing Efficiencies

“…41 Calculation of aerosol radiative forcing employs five spectral bands spanning 4400 to 32 260 cm −1 . 37 The LIDORT radiative transfer model 42,43 is used to calculate the top of the atmosphere (TOA) radiative flux, using surface reflectances from GOME 44 that span from 12 987 cm −1 to 27 027 cm −1 and are extrapolated to cover the shortwave spectrum considered here. Unless noted otherwise, calculations are for all-sky conditions wherein forcing is masked by the GMAO cloud fraction of each column.…”

Tropospheric emissions: Monitoring of pollution (TEMPO)

“…Viewing geometries for each scene are computed based on TEMPO viewing for a given satellite longitude (e.g., 100°W). Surface albedo is based on the GOME albedo database [58], which provides monthly mean surface albedo climatology at a spatial resolution of 1°Â 1°for 11 1-nm-wide wavelength from 335 nm to 772 nm, and is interpolated or extrapolated to TEMPO wavelengths. The independent pixel approximation is assumed for partial cloudy conditions.…”

Validation of Odin/OSIRIS stratospheric NO2 profiles

“…Aerosol information is also included and consists of the stratospheric aerosol extinction climatology for 1999 from Bauman et al [2003aBauman et al [ , 2003b and a Heney-Greenstein phase function (asymmetry parameter 0.7). The surface albedo is taken from Koelemeijer et al [2003].…”