Principal Investigator (PI): Jose Rodriquez, NASA's Goddard Space Flight Center Co-Investigator (Co-PI): Jay Herman, Goddard

This proposal concerns the production of a continuous ultraviolet reflectivity data record for Earth's surface and atmosphere using multiple satellite data records dating back to 1979. The scene reflectivities of Earth at blue and ultraviolet (UV) wavelengths (320 nm to 415 nm) are low over most surfaces (except ice and snow), and are almost independent of the seasonal changes in vegetation on land and in the oceans. This makes it ideal for examining changes in radiation reflected back to space from changes in cloud and aerosol amounts, especially as affected by the start of climate change.

The ultraviolet reflectivity of Earth's surface and atmosphere (clouds, aerosols, and Rayleigh scattering) has been accurately measured since the launch of Nimbus-7/Total Ozone Mapping Spectrometer (TOMS) and Nimbus-7/Solar Backscatter Ultraviolet Radiometer (SBUV) in October 1978. Gaps in the TOMS data record, most notably the period from 1993 to 1997, and the degrading calibration of Earth-Probe/TOMS (1997 to 2006) after 1999, have made it necessary to join the data record from multiple satellites to produce a continuous climate quality Earth System Data Record (ESDR) quality data set. The current reflectivity data record will be extended during the life of this proposal to produce a 35-year (1979 to 2013) continuous ESDR, which can be further extended using the developed software from the proposed work and data from the ongoing Global Ozone Monitoring Experiment-2 (GOME-2) satellite series, Suomi National Polar-orbiting Partnership (Suomi NPP), and followed by NPOESS.

The resulting data, documentation, and software will be made freely available on NASA data servers via ftp bulk download and, for various subsets and images, on the TOMS page at NASA's Goddard Earth Sciences Data and Information Services Center (GES DISC).

Distributed by NASA's GES DISC