Weather experts have said there is a “strong possibility” of the emergence of ‘El Nino,’ impacting this year’s monsoon in India. ‘El Nino’ is a phenomenon in which the warmer ocean currents along the Pacific coast of South America, above normal, divert the flow of moist winds from the Indian Ocean, reducing rainfall in the Indian sub-continent.
However, the precise correlation between ‘El Nino’ and droughts is still unclear, says water resources expert P.M. Natarajan, Member of the Working Group of the Tamil Nadu Planning Commission, and Senate Member of Bharathidasan University.
Though six of the “most prominent droughts in India” since 1871 have been ‘El Nino droughts,’ including those in 2002 and 2009, “…not all El Nino years lead to drought in India,” Dr. Natarajan has said in a recent paper, ‘El Nino Impact On the Indian Water Resources,’ a copy of which he shared with The Hindu.
For instance, 1997-98 was a “strong El Nino year,” but that did not cause any drought in India. On the other hand, a ‘moderate El Nino’ in 2002 resulted in one of the worst droughts, he points out. However, “one thing is clear: El Nino year does affect the weather in India in terms of monsoon rains.”
Referring to India Meteorological Department’s forecast released last month that the rainfall this year was likely to be 95 per cent of the Long Period Average (LPA) and a five per cent above or a five per cent deficit in the southwest monsoon this year, Dr. Natarajan is apprehensive that ‘El Nino’ is likely to affect Tamil Nadu in a bigger way, as the State already face a 62 per cent water deficit annually.
For Tamil Nadu, which is often forced to plead with Karnataka for its due share of the Cauvery water every year, this year’s loss could be significant, he says. “The loss of water during this season is likely to affect the Cauvery delta in a bigger way since Karnataka has to release up to 134 tmcft during this [southwest monsoon) season.
Stating that India’s ‘anticipated per capita storage’ of water should go up to 1,000-1,200 cubic metres, Dr. Natarajan argues that in the long run, only “inter-basin water transfer” could help to bring about this level of storage. “Unless we do that, we cannot create additional irrigation potential and produce 420 million tonnes of foodgrains for the Indian population during 2050, besides producing enough hydro-power” for all.”
To stave off a water crisis, he also advocates other methods of water conservation: rainwater harvesting, groundwater recharge, recycling industrial waste water, desalination of seawater, more emphasis on dry crops cultivation and adoption of micro-irrigation practices.