The Synoptic Climatology of Monthly Mean Surface Temperature in Eurasia in Relation to the 700mb Height Field Over the Northern Hemisphere

摘要

The synoptic climatology of monthly mean surface air temperature anomaly (MMATA) at 115 surface stations in Eurasia is assessed by two types of maps. The first consists of simple linear correlation coefficients between the MMATA at a station and the montly mean 700mb height anomaly (MMHA) at 134 grid points in the Northern Hemisphere. In winter, these fields generally contain two equally important centers: a center of maximum positive correlation approximately 1300km from the reference station and a negative center about 2800km to its northwest. In summer, the positive center is located an average of 800km from the reference station and strongly dominates the MMATA, while the negative center is no longer as important as in winter. The second kind of map is a special type of anomaly composite, constructed by multiplying the correlation coefficient at each grid point by the standard deviation of MMHA at the same point. This map shows the optimum distribution of height anomalies for abnormally warm (or cold) weather for winter and summer in each of several climatologically similar regions into which the Eurasian area is subdivided.