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Calibration of TOMS Radiances From Ground ObservationsVerification of a stratospheric ozone recovery remains a high priority for environmental research and policy definition. Models predict an ozone recovery at a much lower rate than the measured depletion rate observed to date. Therefore improved precision of the satellite and ground ozone observing systems are required over the long term to verify its recovery. We show that validation of radiances from the ground can be a very effective means for correcting long term drifts of backscatter type satellite measurements and can be used to cross calibrate all BUV instruments in orbit (TOMS, SBUV/2, GOME, SCIAMACHY, OMI, GOME-2, OMPS). This method bypasses the retrieval algorithms used to derive ozone products from both satellite and ground based measurements that are normally used to validate the satellite data. Radiance comparisons employ forward models, but they are inherently more accurate than the retrieval This method employs very accurate comparisons between ground based zenith sicy radiances and satellite nadir radiances and employs two well established capabilities at the Goddard Space Flight Center, 1) the SSBUV calibration facilities and 2) the radiative transfer codes used for the TOMS and SBUV/2 algorithms and their subsequent refinements. The zenith sky observations are made by the SSBUV where its calibration is maintained to a high degree of accuracy and precision. Radiative transfer calculations show that ground based zenith sky and satellite nadir backscatter ultraviolet comparisons can be made very accurately under certain viewing conditions. Initial ground observations taken from Goddard Space Flight Center compared with radiative transfer calculations has indicated the feasibility of this method. The effect of aerosols and varying ozone amounts are considered in the model simulations and the theoretical comparisons. The radiative transfer simulations show that the ground and satellite radiance comparisons can be made with an uncertainty of less than l\% without the knowledge of the amount ozone viewed by either instrument on ground or in space. algorithms.
Document ID
20040074234
Document Type
Conference Paper
Authors
Bojkov, B. R. (Science Systems and Applications, Inc. Lanham, MD, United States)
Kowalewski, M. (Science Systems and Applications, Inc. Lanham, MD, United States)
Wellemeyer, C. (Science Systems and Applications, Inc. Lanham, MD, United States)
Labow, G. (Science Systems and Applications, Inc. Lanham, MD, United States)
Hilsenrath, E. (NASA Goddard Space Flight Center Greenbelt, MD, United States)
Bhartia, P. K. (NASA Goddard Space Flight Center Greenbelt, MD, United States)
Ahmad, Z. (Science and Data Systems, Inc. Silver Spring, MD, United States)
Date Acquired
August 21, 2013
Publication Date
January 1, 2003
Subject Category
Space Sciences (General)
Meeting Information
Fall AGU 2003(San Francisco, CA)
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.