RADIATIVE COOLING IN THE VICINITY OF INVERSIONS AND THE TROPOPAUSE,
Abstract
The distribution of radiative cooling in the vicinity of a temperature inversion in the middle troposphere is calculated for several distributions of humidity. When mixing ratios are high throughout the inversion radiative cooling acts to erode the inversion (minimum cooling at the base, maximum cooling at the top). When mixing ratio decreases rapidly upward from the inversion base most of the inversion is a region of reduced cooling, while maximum cooling amounting to several degrees per day occurs in the vicinity of the inversion base. The region immediately below the inversion base is subject to strong radiative destabilization. Verification of the theoretical cooling rates is sought in ten radiometer-sonde ascents at Tucson, Arizona. The radiometer-sonde is only marginally applicable to determining the radiative cooling distribution in the vicinity of the inversions, and random radiometersonde errors and consequences of slant ascent are examined in detail. The radiometer-sonde measurements, when averaged, verify that radiative cooling is so distributed as to tend to maintain the inversion, showing maximum cooling of the order of 2C/day at and below the base and minimum cooling of the order of 1C/day in the upper part of the inversion. No verification was found for the theoretical destabilization of the layer below the inversion base, although errors and scatter of measurements obscure the true distribution. All ten radiometersonde ascents also penetrated the tropopause, and warming or minimum cooling was found at or very near the tropopause in every ascent. Hence the tropopause must be maintained by processes other than radiation. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 15, 1965
- Accession Number
- AD0622737
Entities
People
- D. O. Staley
Organizations
- University of Arizona