Catastrophic heat of 2010 in Moscow from data of ground-based meteorological measurements

Abstract

The results of meteorological ground-based observations in Moscow (mainly at Moscow State University (MSU)) in summer 2010 are discussed. It is shown that the anomalous heat of 2010 has no analogs in the history of meteorological observations in the Russian capital in either the record-breaking values themselves or in their duration. Both the secular records of the monthly mean air temperatures in July and August over the past 230 years and the absolute temperature maximum over the past 130 years were exceeded. For the first time in the history of regular meteorological measurements, the maximal air temperature in Moscow exceeded +38°C, the diurnal mean temperature exceeded +30°C, the monthly mean temperature exceeded +26°C, the soil surface temperature exceeded +60°C, and the deficit of water vapor saturation exceeded 50 hPa. On the whole, the tropical air, which dominated in Moscow, was to a larger degree anomalously hot than anomalously dry. The least relative humidity during the catastrophic heat (16%) only approached the historical minimum (15%). For the first time in the history of measurements for July, the amount of precipitation in July 2010 was only 7.4 mm. In total, these conditions were responsible for the appearance of mass ignition centers in the Moscow region and, as a consequence, of dense smog. The record-breaking ground temperatures over the past 45 years associated with the catastrophic heat were observed at a depth of 320 cm up to the end of 2010.