Temperature, humidity and cloud near fronts in the middle and upper troposphere

✍ Scribed by J. S. Sawyer

• Publisher: John Wiley and Sons
• Year: 1958
• Tongue: English
• Weight: 785 KB
• Volume: 84
• Category: Article
• ISSN: 0035-9009
• DOI: 10.1002/qj.49708436206

✦ Synopsis

Abstract

Exploratory flights through fronts beneath the jet stream confirm that a narrow frontal zone some 30 to 50 mi wide with sharp boundaries is often present at the 500 mb level. On other occasions the temperature changes are more diffuse. The air in and near the frontal zone is usually very dry and must have undergone subsidence.

Dynamic considerations suggest that the very strong temperature gradient of the frontal zone at 500 mb arises from the differential subsidence of air on the cold side of the jet stream which leads to a tilting of the isentropic surfaces.