Seasonal Highlights

Climate in China

During summer 2006, mean surface air temperatures were above normal in most of China with anomalies above 1℃. Positive anomalies over 2℃ were observed in eastern Southwest China and southern Northwest China. For the season, precipitation totals were 30-50% more than average in most of South China, southern Hunan and locations of Henan, Xinjiang, Qinghai and Heilongjiang. Meanwhile, rainfall totals were less than 30-50% in northeastern Inner Mongolia, most of Northwest China and mid-eastern Southwest China.

Climate in the world

During summer 2006, surface air temperatures were recorded above normal in most of the continents. Positive anomalies of 1-2℃ were observed in most of China, West Asia, most of Europe, northern Siberia, locations of West Africa, mid-western America and mid-southern South America, with 2℃ above normal in the regions around Caspian Sea and locations of America. Meanwhile, temperatures were near or below normal in the other regions, and they were 0.5-1℃ below normal in southern West Siberian, Kazakhstan, locations of India, northwestern Australia and Alaska, with more than 1℃ below normal in locations of northern Australia.

For the summer, rainfall totals were more than 30% above average in western and northern India, locations of Central Siberia, eastern West Siberia, southwestern and northeastern America, southern Alaska, locations of West Africa, most of South Africa, most of Tanzania, eastern Australia and locations of central Australia, northern Brazil and southern Argentina. Meanwhile, precipitation totals were near or less than average in the remainder of the world, with more than 30% below average in northern Europe, western West Asia, Central Asia, most of mid-western Siberia, northern China and eastern Southwest China, northwestern America, mid-western Australia, central South America and Northwest Africa, and no precipitation was observed in locations of them. 

General Circulation Features

Northern Hemisphere: During summer 2006, the 500hPa geopotential heights were near normal. Negative anomalies below – 4 dam covered the North Pole. Meanwhile, positive departures above 4 dam controlled northwestern North Pacific, the Caspian Sea, northern Europe and northern Atlantic. For the season, the area and intensity of Northwest Pacific subtropical high were above normal.

Southern Hemisphere: In the 500hPa geopotential height anomaly field, negative anomalies controlled most of the mid-high latitudes except the polar region with anomalies below - 4 dam over southern South Pacific, parts of South Atlantic Ocean and South Indian Ocean. Meanwhile, positive departures above 4 dam covered oceans such as south of Australia and locations of southeastern Pacific.