Desert climate air motion; dry atmosphere near the surface and aloft; the exacerbated exposure to the sun where solar angles are always high. Cold desert climates ("BWk") usually feature hot (or warm in a few instances), dry summers, though summers are not typically as hot as hot desert climates. Unlike hot desert climates, cold desert climates tend to feature cold, dry winters. Snow tends to be rare in regions with this climate. The Gobi Desert in Mongolia is a classic example for cold deserts. Though hot in the summer, it shares the very cold winters of the rest of Central Asia. Cold
Environmental issues in China the country. Approximately 30% of China's surface area is desert. China's rapid industrialization could cause this area to drastically increase. The Gobi Desert in the north currently expands by about per year. The vast plains in northern China used to be regularly flooded by the Yellow River. However, overgrazing and the expansion of agricultural land could cause this area to increase. In 2009, it was estimated that over 200 high-altitude lakes in Zoigê Marsh, which provides 30% of the Yellow River's water, had dried up. In 2001, China initiated a "Green Wall of China" project. It is a project to