Месяц: Декабрь 2011

Assessment of a mudflow hazard in the current period of unstable climate and possible extremal situations is especially important for the Caucasian Black Sea coast. Here mudflows constantly threaten to economic and tourist’s objects and happen due to the mass construction of different structures, including their probable appearance during preparation of XXII Olympic Winter Games of 2014 in Sochi. The hazard assessment of mudflows is made through analyzing their activity and the degree to which they affect the territory. Data on the mudflow activity in the past and present time are extrapolated for the period up to 2015 basing on analysis of the basic changing factors of their formation: meteorological and anthropogenic ones in the interaction with geological conditions. High mudflows activity is expected in the nearest years both on the territory where they were known earlier and also in the areas under intensive development. The highest hazard is possible in 2011 – 2012.

Проведено исследование связи средних и экстремальных дат начала, а также средней и экстремальной продолжительности циркуляционных сезонов внетропических широт Северного полушария с периодами повышения и понижения средней приземной температуры воздуха на полушарии. Для этого проанализированы изменения дат начала и продолжительности циркуляционных сезонов Северного полушария в типизации Б.Л. Дзердзеевского в течение 1899–2008 гг. Показаны различия сезонных характеристик по циркуляционным эпохам и их современные тенденции. Выявлены особенности смены циркуляционных сезонов в период потепления 1930-х годов ХХ в. и современного потепления.

Long-Term Fluctuations of Beginning Dates and Duration of Circulation Seasons of Extra-Tropical Latitudes of Northern Hemisphere N. K. Kononova, L. V. Khmelevskaya
Institute of Geography, RAS
Research of connection of average and extreme dates beginning and also average and extreme duration of circulation seasons of extra-tropical latitudes of Northern Hemisphere with the periods of rise and downturn of mean air temperature over the Northern Hemisphere is carried out. For this purpose changes of dates beginning and duration of circulation seasons over Northern Hemisphere according to classification by B.L. Dzerdzeevskii during 1899–2008 are analyzed. Differences of seasonal characteristics between circulation epochs and their resent tendencies are shown. Features of change of circulation seasons during warming 30th years of XX century and last warming are revealed.