Intercomparison of stratospheric water vapor observed by satellite experiments: Stratospheric Aerosol and Gas Experiment II versus Limb Infrared Monitor of the Stratosphere and Atmospheric Trace Molecule Spectroscopy

Journal Article · Sat Mar 20 00:00:00 EST 1993 · Journal of Geophysical Research; (United States)

DOI:https://doi.org/10.1029/92JD01629· OSTI ID:6616667

Chiou, E W; Larsen, J C ^[1]; McCormick, M P; McMaster, L R; Chu, W P ^[2]; Rind, D ^[3]; Oltmans, S ^[4]

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1. Hughes STX Corp., Hampton, VA (United States)
2. NASA Langley Research Center, Hampton, VA (United States)
3. NASA Goddard Inst. for Space Studies, New York, NY (United States)
4. NOAA Climate Monitoring and Diagnostic Lab., Boulder, CO (United States)

This paper presents a comparison of the stratospheric water vapor measurements made by the satellite-borne sensors the Stratospheric Aerosol and Gas Experiment II (SAGE II), the Nimbus 7 Limb Infrared Monitor of the Stratosphere (LIMS), and the Spacelab 3 Atmospheric Trace Molecule Spectroscopy (ATMOS) experiment. LIMS obtained data for 7 months between November 1978 and May 1979; ATMOS was carried on Shuttle and observed eight profiles from April 30 to May 6, 1985 at approximately 30[degrees]N and 50[degrees]S; and, SAGE II continues to make measurements since its launch in October 1984. For both 30[degrees]N and 50[degrees]S in May, the comparisons between SAGE II and ATMOS show agreement within the estimated combined uncertainty of the two experiments. Several important features identified by LIMS observations have been confirmed by SAGE II: a well-developed hygropause in the lower stratosphere at low- to mid-latitudes, a poleward latitudinal gradient, increasing water vapor mixing ratios with altitude in the tropics, and the transport of dry lower stratospheric water vapor upward and southward in May, and upward and northward in November. A detailed comparative study also indicates that the two previously suggested corrections for LIMS, a correction in tropical lower stratosphere due to a positive temperature bias and the correction above 28 km based on improved emissivities will bring LIMS measurements much closer to those of SAGE II. The only significant difference occurs at high southern latitudes in May below 18 km, where LIMS measurements are 2-3 ppmv greater. It should be noted that LIMS observations are from 16 to 50 km, ATMOS from 14 to 86 km, and SAGE II from mid-troposphere to 40 km. With multiyear coverage, SAGE II observations should be useful for studying tropospheric-stratospheric exchange, for stratospheric transport, and for preparing water vapor climatologies for the stratosphere and the upper troposphere. 32 refs., 14 figs., 2 tabs.

• OSTI ID: 6616667
• Journal Information: Journal of Geophysical Research; (United States), Vol. 98:D3; ISSN 0148-0227
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
SATELLITES
COMPARATIVE EVALUATIONS
DATA ACQUISITION SYSTEMS
STRATOSPHERE
ECOLOGICAL CONCENTRATION
TROPOSPHERE
WATER VAPOR
REMOTE SENSING
CORRECTIONS
MIXING
SPECTROSCOPY
EARTH ATMOSPHERE
EVALUATION
FLUIDS
GASES
VAPORS
540120* - Environment
Atmospheric- Chemicals Monitoring & Transport- (1990-)