The El Nino effect in the Pacific is well-known by anyone who takes even half an interest in the weather. Less well-known – mainly because its discovery only occurred 15 or so years ago – is the Indian Ocean Dipole. Like El Nino, the IOD involves the regular movement of vast amounts of warm seawater over long distances, disrupting weather patterns locally and around the globe. This year’s patchy Indian monsoon, for instance, is blamed on the IOD having shifted to its “negative” stage, with the warmer water centring off Indonesia rather than to the west of the subcontinent.
As scientists learn more about such natural phenomena, the arguments about climate change become more complicated. What is the interplay between the man-made greenhouse effect created by CO2 emissions and the regular changes that occur cyclically in oceanic and atmospheric currents? Into the debate now comes some fascinating research from the Masdar Institute into climate variability – natural phenomena rather than human-induced climate change – as it affects the country’s rainfall trends.
As The National reported yesterday, the study published in the Journal of Hydrology, found that rainfall has actually been increasing in the UAE, except for a sharp drop observed in 1999 that corresponded to recorded changes in six climate oscillations. The leading scientist, Prof Taha Ouarda, said that these findings show that UAE rainfall trends were not associated with permanent climate change caused by human activity.
The Masdar Institute study helps underline how much science still has to learn about climate and the intertwined variabilities affecting the environment. But as the gaps in knowledge are filled, so can some of the uncertainties of weather and climate be smoothed out. Prof Ouarda claims his research will help predict rainfall patterns for coming years.
With so many hundreds of millions of people from Africa to India to South-East Asia all dependent on the Indian Ocean Dipole and the life-giving rains of the monsoon, more intensive research is desperately needed into its complex variations. It is truly astonishing that the IOD was only identified and given a name in 1999.