‘The Little Girl’ — La Nina — has had an outsized impact across globe since manifesting itself in mid-2010. La Nina and its equally rumbustious sibling, El Nino, come about when the waters of the eastern and central Pacific Ocean along the equator become unusually cold or warm. These changes in the Pacific produce swings in atmospheric pressure, winds, temperature, and rainfall that have a global impact. These coupled with changes in the ocean and atmosphere are collectively called the El Nino/Southern Oscillation (ENSO). For India, an El Nino is often a cause for concern because of its adverse impact on the south-west monsoon; this happened in 2009. A La Nina, on the other hand, is often beneficial for the monsoon, especially in the latter half. The La Nina that appeared in the Pacific in 2010 probably helped last year’s south-west monsoon end on a favourable note. But then, it also contributed to the deluge in Australia, which resulted in one of that country’s worst natural disasters with large parts of the north-east under water. It wreaked similar havoc in south-eastern Brazil and played a part in the heavy rains and consequent flooding that have affected Sri Lanka.
It is becoming increasingly clear that global warming is contributing to the impact that ENSO has. The Indian Ocean is warming rapidly. There are already indications that this warming along with the growing temperature of the western Pacific is influencing the effect of a La Nina. A paper, ominously titled ‘The Perfect Ocean for Drought,’ which was published in the journal Science in 2003, linked the prolonged droughts from 1998 to 2002 that afflicted the United States, southern Europe, and south-west Asia to the warmth of these ocean waters during a protracted La Nina. Such heightened ocean temperatures may well have played a crucial part in weather-related events in recent months. While the La Nina that developed in mid-2010 lent a helping hand to the south-west monsoon, the warmth of the tropical Indian Ocean may have prevented a more equitable distribution of rainfall — eastern Uttar Pradesh, Bihar, Jharkhand, and much of West Bengal received far too little of it. The warming of the Indian Ocean and western Pacific probably provided the extra moisture and energy for the exceptionally heavy rains that Australia and Sri Lanka experienced. It could be one reason why in India the north-east monsoon, which is usually retarded by a La Nina, has this time seen a surfeit of rain. The writing on the wall is clear enough: global warming will worsen the swings of climate variability brought about by factors like ENSO, making extreme weather events such as droughts and floods more frequent. The world needs to pay heed.
Keywords: La Nina, El Nino/Southern Oscillation, drought, natural disaster
Good and great article. Creates awareness in the public.. So lets create an eco-friendly environment.. Start planting trees.
These unprecedented events show that climate change is the biggest challenge before mankind in the 21st century even bigger than terroism or we can term it as natural terrorism which every person on this Earth is responsible for.Although global warming and global cooling are natural cyclic events according to Climatology and this is the period of the former one but human has added to its effect as a catalyst.We will have to take stringet steps to curb it otherwise humane graves shown in the Movie 2012 could be true.
The situation seems alarming.The time has come that the summits on climatic discussions result in results.The vexed issue between the developing and developed countries is harming the both.The consensus needs to be build for the betterment of our Universe. The erratic nature of the weather in all parts of the universe has resulted in economic and numerous casualties. No development seems to be enough to counter the wrath brought by natural calamities. The superpower U.S. too couldn't do anything when it was hit by Katrina.Before the retaliation of the nature to human negligence behavior creates havoc for human race,its time to act .
Good article. made interesting reading.
All revolves around global warming and having known what are the man made causes, the entire world leaders and the scientific community have to thwart the incessant abuse of the natural resources forthwith with firm determination. At least 50 to 100 years later there could be a change for the better and the future generation can thank their predecessors.
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