Climate of Our Future

http://www.sciencedaily.com/releases/2009/12/091230183104.htm

ScienceDaily (Jan. 3, 2010) — The Indian Ocean Dipole (IOD), an oscillation of sea surface temperatures in the Indian Ocean, has become a major influence on the weather variations in the Indian Ocean region. During positive IOD events, abnormally warm sea surface temperatures in the western Indian Ocean are accompanied by severe droughts over the Indonesian region and heavy rainfall over east Africa

To learn more about IOD patterns, Nakamura et al. studied a 115-year coral record from Kenya. They analyzed coral oxygen isotope ratios, which trace rainfall anomalies, to reconstruct IOD variability. The results add to evidence that the IOD has been occurring more frequently in recent decades. The researchers find that before 1924, the IOD occurred approximately every 10 years, but since 1960, IOD events have been occurring approximately 18 months to 3 years apart.

The authors suggest that global warming effects on the western Indian Ocean have driven the observed shift in IOD variability and note that the IOD has replaced the El Niño-Southern Oscillation as the major driver of climate patterns over the Indian Ocean region  Keep Reading