TEMPERATURES AT THE 10-MB (101,000-FOOT) LEVEL
Abstract
Examination of 356 radiosonde soundings reaching from 15 mb to 10 mb indicated the following facts: (1) On the average, the 10-mb temperatures are within the -38 deg to -52 deg C range. (2) Exceptional values of -5 deg to -10 deg C were found in 4 cases at 10 mb, indicating that temperatures above 0 deg C may be reached occasionally. (3) The lapse rate in the 20.6-to 30.9-km layer is much smaller than usually indicated. The rate of warming with height decreases rapidly with increasing elevation. (4) In 16% of all cases, the 10-mb level lies in a region in which cooling with height occurs. This cooling may take place in the whole 100- to 10-mb layer or in thinner layers. (5) The average 24-hr temperature change at 10 mb is at least twice as great as that at 100 mb. This change increases regularly with height in the 100- to-10mb layer. (6) There is a marked seasonal variation of the mean and extreme temperatures at 10 mb. The highest means and extremes occur in July. (7) On daily synoptic map covering an area from 9 deg N to 79 deg N, the extreme range of 100-mb temperatures was 36 deg C, and that on the 10-mb map was 15 % C. (8) In the mean maps the range of 100-mb temperature over USA and Central America was 41.6 deg C, that on the 10- mb map was 2.7 deg C. A barotropic layer seems to be present from the Equator to the Pole in all months. This may lie anywhere between 60 and 10 mb.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1953
- Accession Number
- AD0020871