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A comparison of small and larger mesoscale latent heat and radiative fluxes: December 6 case studyBecause of the small amounts of water vapor, the potential for rapid changes, and the very cold temperatures in the upper troposphere, moisture measuring instruments face several problems related to calibration and response. Calculations of eddy moisture fluxes are, therefore, subject to significant uncertainty. The purpose of this study is to examine the importance of latent heat (moisture) fluxes due to small and larger mesoscale circulations in comparison to radiative fluxes within cirrus. Scale separation is made at about 1 km because of significant changes in the structures within cirrus. Only observations at warmer than -40 C are used in this study. The EG&G hygrometer that is used for measuring dewpoint temperature (Td) is believed to be fairly accurate down to -40 C. On the other hand, Lyman-Alpha (L-alpha) hygrometer measurements of moisture may include large drift errors. In order to compensate for these drift errors, the L-alpha hygrometer is often calibrated against the EG&G hygrometer. However, large errors ensue for Td measurements at temperatures less than -40 C. The cryogenic hygrometer frost point measurements may be used to calibrate L-alpha measurements at temperatures less than -40 C. In this study, however, measurements obtained by EG&G hygrometer and L-alpha measurements are used for the flux calculations.
Document ID
19940017862
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Gultepe, I.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Starr, David
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Heymsfield, A. J.
(National Center for Atmospheric Research Boulder, CO., United States)
Date Acquired
September 6, 2013
Publication Date
December 1, 1993
Publication Information
Publication: NASA. Langley Research Center, The FIRE Cirrus Science Results 1993
Subject Category
Meteorology And Climatology
Accession Number
94N22335
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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