Seasonal Highlights

Climate in China

During the spring, mean surface air temperatures were observed 1℃ above normal in most of China except for most of Yunnan, western South China and eastern Northeast China, with temperatures 2-3℃ above normal in the middle and lower reaches of the Yangtze River and most of Xinjiang.

In the season, precipitations were observed more than 30% below normal in southern Xinjiang, southern Hetao and western Jiangnan. Meanwhile, precipitations were 30-100% above normal in most of Northeast China, eastern North China, eastern Northwest China, northern Xinjiang, western Tibet and southern Southwest China, with about 200% above normal in locations of above regions.

Climate in the world

During the spring, mean surface air temperatures were observed above normal in most of the world, with temperatures 2-3℃ above normal in most of Eurasia and parts of America. While temperatures were 1℃ below normal in areas between western Canada to eastern Alaska

In this spring, precipitations were observed 30-100% above normal in most of northern China, most of the West Siberian Plain, central America and northwestern Australia. Meanwhile, precipitations were more than 30% below normal in most of southern China and southern Xinjiang, parts of Europe, eastern North Africa, most of the Indian Peninsula, western and eastern Australia, western and southeastern America and parts of South America, with no precipitation in parts of above regions.

General Circulation Features

Northern Hemisphere: During this spring, the mean 500hPa geopotential height field exhibited a 4-wave pattern at the mid-high latitudes. In the 500hPa height anomaly field, negative anomalies below -4 dam covered Alaska Bay, Baffin Bay west to and the Arctic Ocean north to the Greenland. Meanwhile, positive anomalies above 4 dam covered Europe and the oceans west to it, central Asia, the Far East of Russia and the Bering Sea, central North America and oceans west to it, with central values above 8 dam over the western Bering Sea.

Southern Hemisphere: During this spring, 2007, zonal circulation prevailed at the mid-high latitudes. In the 500hPa geopotential height anomaly field, negative anomalies below -4 dam controlled the southern South Pacific Ocean, the southern South Atlantic Ocean, the southern South Indian Ocean. Meanwhile, positive departures above 4 dam covered most Antarctica, the regions along 40°S latitude of the South Pacific, with central values above 8 dam over Antarctica.