Like Omar Khayyam’s “moving finger”, the southwest monsoon of 2012 having poured, is about to move on, leaving in its wake some lessons and a major enigma.
The first lesson is that second-guessing Mother Nature is a mug’s game. It is so for professional meteorologists, the much-maligned India Meteorological Department (IMD), and most of all, armchair know-it-all amateur commentators such as yours truly. Less than two months ago, I had voiced my fear that 2012 might well be as bad as 2009 (when the monsoon precipitation was only 77 per cent of the long-period average), based on rainfall until the end of July (“Drought forebodings,” Business Standard, August 5, 2012). As every viewer of television news knows, the rainfall this monsoon (which officially ends on September 30) would be around 820 mm, or over 92 per cent of the average.
Copious rains in August and September made the oft-revised forecasts of IMD go awry yet again. They also showed the untimely boasts of amateur weathermen like me of being able to predict short-period rains to be hollow. Formations of rain-bearing clouds as seen through satellite imagery changed rapidly, often more than once a day, and followed no previously seen patterns. No one, including the otherwise reliable Center for Ocean-Land-Atmosphere Studies, was able to predict this, not even the two cloudbursts in Uttarakhand that wreaked so much damage in quick succession. IMD issued alerts after the fact, as always!
Normally, rain-bearing clouds from the Bay of Bengal cross the Orissa shore and travel west-north-westwards, covering Madhya Pradesh, Maharashtra and Gujarat, with reducing precipitation. If there are depressions in the Bay, the cloud formations are stronger and sometimes go all the way to western Rajasthan, as happened in 2005. This August, the currents followed a more northerly course, covering Jharkhand, Bihar, Uttar Pradesh and Rajasthan, but bypassing northern Maharashtra and Gujarat until late August. So even as Jaipur and Churu were flooded, Gujarat remained dry (Saurashtra nearly bone-dry), a situation seldom seen.
The 2009 monsoon was affected by Madden Julian Oscillations (MJO). This is a 30-60 day cycle of eastward movement of moisture over the tropical region, from the Indian Ocean to the Pacific and sometimes even to the Atlantic. Most of this August and September, according to the latest report (September 24, 2012) from the Climate Prediction Center of the National Oceanic and Atmospheric Administration (NOAA) of the United States, the positive (or eastward-moving) anomalies associated with lower rainfall were weak. The negative (or westward-moving) anomalies gained strength in August and September, with markedly improved precipitation around 800 E latitude (connecting Jabalpur and Kanpur). They have decreased considerably now according to NOAA. MJO is also associated with the El Nino phenomenon (which causes low rainfall in the subcontinent), but that association is weaker this year than feared earlier.
That is the scientific explanation — we might call it reverse MJO, to coin a phrase (I found no such reference!) Unfortunately, this satisfactory rationale is available after the fact, which is not of much use in prediction.
The second lesson, driven home with unusual thrust this year, is that season-long forecasts are of little use. Just assume that the monsoon calendar was reversed, that is September was June and August was July. The total precipitation would be exactly the same, but at the end of July, we would have been whistling a merry tune, expecting (and probably reaping) a super bumper kharif crop. As this paper editorially noted, due to “the rains’ spread in space and time...early season moisture stress seem(s) to have endured,” (“Seven years in a row,” Business Standard, September 28, 2012). The agriculture ministry expects the kharif crop to decline by 10 per cent. So distribution is all, the total nothing, as far as the monsoon rains are concerned.
Some press reports suggest that Ashwini Kumar, the minister of state whose charge includes IMD, has taken the department to task and asked it to improve its short-term forecasting and not bother so much about the season predictions. Will the high-and-mighty Pooh Bahs of IMD come down to earth from their obsessions of multi-variate dynamical models, which have failed so spectacularly? Harder to predict than the extent of rain, but absolutely essential!
If the direction to IMD is true, this year’s rain anomalies would have achieved what years of my commenting has failed to do. We would of course miss the spectacle of weather anchors on television announcing breathlessly everyday how the monsoon is catching up with the “deficit,” as if it were a run chase in a limited overs cricket match!
The last and major lesson is the value of contingency planning. As I had noted earlier, this year the government from the prime minister on down had worried about possible drought from mid-July onwards and measures to counter its effect were set in place. They may not have been needed in full, but undoubtedly they have helped reduce the adverse impact in the affected areas. If our planning moves away from fair weather forecasting to factor in likely adversities, it would be a major gain. This lesson also needs to be internalised in connection with the overall economy, especially at its current delicate position.
The above-mentioned editorial also noted that for seven years now, monsoons have started later and lingered on into late September. Environmentalists have warned us for some time now that the immediate consequence of global warming for countries like India would be an unpredictable quantum and spread of rains. The fear is not so much about inadequate precipitation — in fact, an excess could be more likely — but about the period over which it is spread. The possibility of receiving the same or larger amount of rain in fewer days, not bound by the earlier conventional time-frame, is real and increases with the growing warming of the globe.
Nature is bountiful in showering us with over 3 trillion cu m of precipitation a year, among the largest amounts in the world. The enigma is that it comes with the price tag of its capriciousness. India’s life-blood is the monsoon. How well we preserve whatever moisture we receive in whatever period will impact our future far more than any policy reforms or globalisation.
The writer taught at the Indian Institute of Management, Ahmedabad, and helped set up the Institute of Rural Management, Anand
