Accession Number : AD0870905

Title :   Frequencies and Durations of Extreme Surface Temperatures,

Corporate Author : ARMY MISSILE RESEARCH DEVELOPMENT AND ENGINEERING LAB REDSTONE ARSENAL AL PHY SICAL SCIENCES DIRECTORATE

Personal Author(s) : Martin, David W.

Report Date : 20 APR 1970

Pagination or Media Count : 28

Abstract : The report presents partial results of an inquiry into frequencies of surface temperatures and durations of extreme surface temperatures at stations in hot and cold regions of the northern hemisphere. Twelve maps show the temperature which is exceeded (on the cold side) 1 percent of the time and the duration at the -40F threshold which is exceeded 1 percent and 5 percent of the time for the 4 months December, January, February, and March. Three tables give temperature duration at various thresholds and probability levels for three Canadian and Alaskan, three Siberian, and one southwest United States station for the months October through April (cold stations) and April through October (hot stations). The frequency maps changed little from month to month; however, large changes were observed in 1 and 5 percent durations below -40F. Changes in durations were attributed mainly to varying synoptic and diurnal influences on temperature: synoptic effects dominated in December and January; diurnal influences became important in February and March. Because the thresholds chosen were all higher than typical nighttime temperatures, duration distributions at the hot station were very compact. Changes in these duration frequency distributions were due mainly to changes in the magnitude of the temperature. Thus 2 months which had similar mean temperatures had similar distributions of duration for the same threshold. (Author)

Descriptors :   (*ATMOSPHERIC TEMPERATURE, NORTHERN HEMISPHERE), THERMAL STABILITY, METEOROLOGICAL CHARTS, PROBABILITY, TABLES(DATA), ARCTIC REGIONS, CANADA, ALASKA, SIBERIA, UNITED STATES.

Subject Categories : Meteorology

Distribution Statement : APPROVED FOR PUBLIC RELEASE