Monthly Highlights

Climate in China

During November, monthly mean surface air temperatures were 2-5℃ above normal in most of Northeast China and Jiangsu. In the rest of China temperatures were near normal.

In this month, rainfall totals were more than 50% above normal in the northwestern Xinjiang, eastern Northeast China, eastern Tibet and parts of Sichuan, Guizhou, Guangxi, Shandong and Jiangsu, with 400% more than normal in part of Northeast China. Meanwhile, in the rest of China rainfall totals were near or below normal, with no precipitation in part of it.

Climate in the World

During November, monthly mean surface air temperatures were generally above normal in most of the world, with more than 2℃ above normal in most of Russia, Kazakhstan, Japan, Alaska, western Canada, northeastern America and South Africa, and about 6~9℃above normal in most of Center Siberia.

In this month, rainfall totals were more than 50% above normal in the south-central and southeastern Europe, northwestern West Asia, most of Center Asia, northern West Siberia, eastern Center Siberia, part of the Far East, most of Alaska, southern America, eastern Australia, part of South America, and even 200% more than normal in parts of above regions. Meanwhile, rainfall totals were about 50-100% less than normal in western Europe, Mongolia, South Asia and most of Southeast Asia, northern American, South Africa, part of Australia and the coasts of northeastern Brazil.

General Circulation Features

Northern Hemisphere: During November, the mean 500hPa geopotential height field exhibited a three-wave pattern at the mid-high latitudes. The high over the northern North Atlantic Ocean was stronger and the East Asia trough shifted more eastward than normal. In the height anomaly field, positive anomalies dominated the northern North Atlantic Ocean, areas from Baikal Lake to Japan and south-central Canada, with center values above 16 dam near the northern North Atlantic Ocean. Meanwhile, heights over the remainder of the mid-high latitudes were generally near or below normal, with anomalies of below –8 dam over the Novaya Zemlya and Bering Sea. The Northwest Pacific subtropical high was stronger than normal, and extended westward obviously.

Southern Hemisphere: During November at the mean 500hPa geopotential height field, zonal circulation prevailed over the mid-high latitudes. In the height anomaly field, negative anomalies covered the areas from the south-western South Indian Ocean to the eastern South Atlantic Ocean. Meanwhile, heights in the remainder of the mid-high latitudes were near or above normal, with departures above 8 dam over the areas south-east to South America.

Tropical Features

Sea Surface Temperatures (SSTs): During November, above 0.5℃ SST anomalies dominated most of the equatorial Pacific, with central values above 1.5℃ around the date line. Meanwhile, positive anomalies above 0.5℃ still controlled the most of equatorial Indian Ocean. In this month, the SSTa indices of NINO 4, NINO 3, NINO 1+2 and NINO Z were 1.2℃, 0.5℃, 0.3℃and 0.8℃, respectively, and all rose slightly since last month.

Subsurface Temperatures: During November, the abnormally warm water strengthen remarkably in the central equatorial Pacific, with values above 3℃ in the area between 130°W to 180°. The areas of negative anomalies in the eastern equatorial Pacific expanded slightly.

Warm Pools: During November, the area of the western equatorial Pacific warm pool and equatorial Indian Ocean warm pool were both larger than normal, and their intensities were both stronger than normal.

Wind Field: In this month, at the lower troposphere (850hPa), 2m/s westerly anomalies still controlled most of the equatorial Pacific. Compared with last month, the westerly anomalies strengthened over the eastern equatorial Pacific but weakened over the western and central equatorial Pacific. At the upper troposphere (200hPa), easterly anomalies covered most of the equatorial Pacific, with center values strengthened obviously compared with last month.

Southern Oscillation: During November, the Southern Oscillation Index was –0.7.

Convection over the Tropics: In this month, the anomalous outgoing longwave radiation (OLR) distribution exhibited that convections enhanced obviously over the areas between 150°E and 180° along the equator, and suppressed over Indonesia. In the lower troposphere (850hPa) divergent wind field, the convergent center was near 165°E over the equator and the divergent center was around 90°W, 5°N. Correspondingly, at the upper troposphere (200hPa), the divergent center was near 165°E over the equator, and the convergent center was over 110°W, 5°S.

ENSO Monitoring and Forecasting

a) During November, above 0.5℃ SST anomalies dominated most of the equatorial Pacific. The SSTa indices of NINO 4, NINO 3, NINO 1+2 and NINO Z all rose slightly since last month.

b) In this month, the abnormally warm water enhanced remarkably in the central equatorial Pacific, with center values above 3℃.

c) The Southern Oscillation Index remained negative value.

d) At the lower troposphere (850hPa), westerly anomalies still controlled most of the equatorial Pacific.

e) Convections enhanced obviously over the areas between 150°E and 180° along the equator, and suppressed over Indonesia.

Recent oceanic and atmospheric status in the tropical Pacific showed that El Nino conditions continued.