Seasonal Highlights

Climate in China

During boreal winter 2007/2008 (Dec. 2007-Feb. 2008), mean surface air temperatures were 1-2℃ above normal in central and northern Northeast China, most Tibet, southern Qinghai and western Sichuan, with over 2℃ in locations. Temperatures were near or below normal in other regions, with 2-4℃ below normal in western Inner Mongolia, northern Ningxia, northern Gansu and southwestern Xinjiang.

For the season, precipitations were observed 50-200% more than average in most Northwest China, parts of Sichuan and Yunnan, western Shanxi and parts of Heilongjiang, with 400% in locations. Meanwhile, precipitations were observed near or less than average in other regions, with 30-80% less than average in parts of northern and south of central Northeast China, eastern North China, central Tibet and parts of northern Xinjiang.

Climate in the world

During the winter, mean surface air temperatures were observed 1-2℃ above normal in most Europe and Russia, northern Northeast China, the Tibetan Plateau, western Indo-China Peninsula, eastern and southern North America, northern Alaska, parts of South America and central Australia, with 4-6℃ in northern Europe and central Russia. Meanwhile, temperatures were observed 1-2℃ below normal in most the mid latitudes of Asia, central and western North America and parts of Australia, with over 4℃in Central Asia.

For the season, precipitations were observed 30-50% more than average in parts of northern Europe, north of central Russia, most Northwest China, parts of India, central and eastern America, western South America, western and eastern Australia, with over 100% in locations of above regions. Meanwhile, precipitations were observed 30-80% less than average in southern and parts of eastern Europe, eastern West Asia, northwestern India, southern Russia, Mongolia, North China and parts of Northeast China, southern and north of central North America, Alaska, parts of South America, eastern West Africa and central Australia, with no precipitations in locations of above regions.

General Circulation Features

Northern Hemisphere: During the winter, the mean 500hPa geopotential height field exhibited a 3-wave pattern at the mid-high latitudes. In the 500hPa geopotential height anomaly field, positive anomalies above 4 dam covered the northeastern North Pacific, the northwestern North Atlantic and most Europe, with central values above 8 dam over the northeastern North Pacific. Meanwhile, negative anomalies below -4 dam covered the regions from Northeast Asia to Alaska and southern Greenland. Heights were near normal in other regions.

Southern Hemisphere: For the season, zonal circulation prevailed at the mid-high latitudes. In the 500hPa geopotential height anomaly field, negative anomalies below -4 dam covered most of the regions south to 60°S, with central values below -8 dam over the polar region. Meanwhile, positive anomalies more than 4 dam covered parts of the mid-latitudes oceans. Heights were near normal in other regions.