What Leads To Unpredictable Monsoons?

India, for long known as an agricultural economy, accounts for less than 15 per cent of GDP through agricultural produce. That figure may seem low, but then, a majority of the population is dependent on agriculture for livelihood. With irrigation methods lagging behind the global benchmarks, significant agricultural land is dependent on rains. But predicting India’s monsoon-based rains is as easy as predicting the fate of an Indian, no-big-star movie!

In fact the joke goes that if the weatherman has predicted a clear day during rainy season, be sure to find yourself stranded on waterlogged roads, and vice versa. To be fair, MET department’s accuracy has been on a rise every passing year, but still, we won’t suggest you to make bets based on their announcements.

Globally, a simple fact that weather patterns are interconnected took centuries to find consensus. It shouldn’t have been a hard thing to swallow, since one cannot divide atmosphere the way one divides countries. There have been various phenomena known to occur across the globe, which dramatically vary the usual, seasonal weather conditions at a place. India is no exception. We, too, have our fair share of sorrows – phenomena of El Nino and La Nina have perplexed our meteorologists as well.

Before we dwell upon what these phenomena are, let us contemplate on what can go wrong if weather pattern changes for an area. Instead we must ask what not. Crop production can hit a nadir; temperature fluctuation can result in change of vegetation pattern of an area, and associated disappearance of various dependent animal species. Plus, it can lead to wars! How? Somebody said that the next world war would be fought on water, and it doesn’t need to be explained how drainage in an area depends on weather. There are various reports that suggest that civil conflicts in various areas of the world rise by as much as 50 per cent when El Nino causes temperatures to rise and rains to fail.

Human beings are concerned, to the limited extent they are, for weather change because they have systematically evolved their ways of living, planned their cities in a given way, and are now used to live a comfortable life – even at the expense of environmental degradation.

It’s not that only human activities are causing global temperature variations; Earth is not a dead planet. It is very much like a living organism, with its own way of dynamic functioning. Earth’s axial tilt at 23.5 degree keeps on varying to a limited extent. Its mean length from the Sun at different parts of the year hasn’t remained unchanged over the millennia. The magnetic field around Earth, that protects us from Solar Flares, has been known to vanish for considerable periods over time – thereby exposing life on Earth to danger. But that way, change is also induced – new species originate; older ones perish. In fact, oxygen that we cannot live without has not been on the planet forever.

It came much later in the planet’s history – after being produced by first Cyanobacteria (photosynthetic micro-organisms). Even when humans were not known to interfere so much with their environment, temperatures varied (so what they show in Ice Age movies is somewhat true!). Before the last ice-age ended some 12,000 years ago, vast swathes of oceans were frozen and that is how human beings could migrate from Africa and Asia to isolated masses of lands like Andaman and Nicobar Islands and Australia (no, you didn’t have good ships, then; not even bad ones, actually!)

So what’s the brouhaha about El Nino and La Nina? They mean “the little boy” and “the little girl” respectively, and just like icky irate kids, they can create big mess. During El Nino, the usual east-to-west equatorial current in the Pacific Ocean weakens or reverses, pushing warm waters to the west coast of South America. Usually, a cold current flows along the coast of Peru in South America; this gets replaced by a warm current in an El-Nino year. Results, as we said, are dramatic. Otherwise dry Atacama Desert in Chile and Peru gets rain, resulting in a feast for the sheep reared in the surrounding areas. But it also results in the failed monsoons in South Asia (India, Bangladesh, Sri Lanka, Nepal, Bhutan and Myanmar) and South-East Asia (Indonesia, Thailand, Malaysia, Vietnam, etc.). It results in droughts in Austro-Asia, but rains, floods and landslides in South America; in addition, it brings with it, increased frequency of tropical cyclones in Tahiti, considerably warm winters in the US, mortality of Seabirds, and increased cases of malaria in the regions with high rainfall. The last it happened in India was in 2009. Most of you would distinctly remember the unbearably stretched summers that year! Quite opposite happens during La Nina – we receive floods and South America goes drier than usual.

Usually the trend of El Nino and La Nina is known to occur with a frequency of two to seven years, but we are far from predicting it accurately. Sometime back, it so happened that something contrary to this phenomenon happened – climatologists simply came up with a new term for the unexplained event – El Nino Modoki! Modoki, in Japanese, means “similar, but different”. It speaks volumes about our helplessness when it comes to regulating nature.

The southwest monsoon is expected to reach the eastern and western parts of the country by June 22. This year, rains have been 42 per cent less than normal, so far. Odds of India experiencing a weak monsoon are 50-50. MET department officials predict that even if El Nino were to hit Indian monsoons, it would only be during the second half of the monsoon, i.e., after August. So we are not in for a year as bad as 2009, according to them. But who knows – they may just come up with a new term, should their forecast fail. After all, there are so many languages in India alone – we will certainly not fall short of new terms to convey, “similar, but different!”

But yes, it’s true that there is no one-to-one correlation between El Nino and the monsoon here, which means that in spite of El Nino we can have good rains. Besides, in 2009, in spite of a 23 per cent shortfall in southwest monsoon, food-grain production was just seven per cent less than the previous year's.

Agreed that our civilization is much more capable to deal with changes in climate, but just to give you a perspective of what effects rain-pattern changes can have, sample this: a majority of historians now believe that sudden disappearance of Harappan civilization was due to sudden change in rain patterns, resulting in lesser rainfalls in Indus plains in today’s Pakistan. If a major civilization at that time could go into oblivion, rest assured that at least some parts of the country will feel the heat if the little boy chooses to pay us a visit more often!