|
|
| | | Navigate the Atlas:  | |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| | | Indian Ocean Dipole |
Maintained by IOC
 |
| |
Text-only Printer-friendly version
| | The Indian Ocean Dipole (IOD) is a climate mode that occurs inter-annually in the tropical parts of the Indian Ocean. The IOD was not identified until 1999 by Professor Yamagata, Dr Saji and associates of the Climate Variations Program of Frontier Research System for Global Change, however, its occurrence can be traced through the coral record to the mid-Holocene period (the Holocene period dates from 11,000 years before present to present). Typical of climate oscillations, the IOD experiences a ‘positive’ phase and a ‘negative’ phase. During a positive IOD event, the sea-surface temperature (SST) drops in the southeastern part of the Indian Ocean: off the northern coast of Australia, the eastern coast of Japan and throughout Indonesia; while the SST rises in the western equatorial Indian Ocean: off the eastern coast of Africa, from the northern half of Madagascar to the northern edge of Somalia. Furthermore, convective patterns increase in the northern half of Africa, India and off the eastern coast of Africa. Inverse conditions exist during a negative IOD event, as illustrated below. |  | | | | The negative IOD - which is, in effect, the reversal of the positive IOD - complete with increased convective activity over Australia, Indonesia and Japan. |  | | | | Understanding ocean-atmospheric interactions that result in climate modes such as IOD will not only increase weather and climate forecasting capabilities in the Indian Ocean, it is and important part of understanding current global climate variability. Images courtesy of A.Suryachandra Rao of the Institute for Global Change Research, Yokohama City, Japan | | | | |
 | | | | |
|
|
979 Topics - 5229 Related Knowledge - 11257 Members - 47 Editors |
freeMem:175,852,424 totMem:478,871,552 reqNum:1106119 openSessions:0 generationTime:2013/05/23 18:33:13 |
E-Mail Topic link