Northeast Siberia

Selenium deficiency has been identified iu humans iu a broad area of China, stretching from the northeast to the southwest. Two syndromes are evident Keshan disease, an endemic cardiomyopathy which affects children, and Kashin-Beck disease, an edemic osteoarthropathy (big-joiat), also mainly involving children, which occurs iu eastern Siberia and parts of China. As a result of these observations, a protective effect for selenium has been proposed, and various selenium-containing preparations have been appHed to preserve animal and human health. 

The Messoyakha gas hydrate field is the first exemplar for gas production from hydrate in the permafrost. Hydrates were produced from this field semicontinu-ously for over 17 years. The field is located in the northeast of western Siberia, close to the junction of the Messoyakha River and the Yenisei River, 250 km west of the town of Norilsk, as shown in Figure 7.29. 

The test site, shaped like an irregular polygon and familiarly called the polygon, is a 19,000 km" zone in the northeast of the newly independent Republic of Kazakhstan, 800 km north of the Kazakh capital Alma-Ata. The zone lies southwest of the Irtysh River which flows into Kazakhstan from China and which for a short stretch, where it veers sharply northwards on its way to join the Ob River in Siberia, forms part of the polygon boundary (see Fig. 10.16). The USSR conducted 465 nuclear tests at three locations called technical areas within the polygon over a period of 40 years (1949-1989) for military and peaceful purposes. 

Northern cold anticyclone intrusion (7-8% of storms). Cold air from the Arctic or from temperate latitudes over the Urals, Western Siberia, and Kazakhstan rushes southward to the atmospheric depression zone over Turkmenistan. The passage of the sublatitudinally extending atmospheric front over the Aral Sea causes strengthening of northern and northeasterly winds to storm magnitudes. 

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