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TEHELKA [DELHI] – 16-09-2006
Doomsday? Not Yet, say experts
The Barmer flood was produced by freak weather, not global phenomena. That will take
longer to manifest
Himanshu Bhagat
New Delhi
Marooned: Rajasthan police look for survivors in Kawas village, Barmer district
Weather fluctuations that occur over a few decades are not unusual, after that they could
reverse themselves
People have short memories,” says B. Lal, director general, Indian Meteorological
Department referring to the recent floods in Barmer, usually in the news for being
drought-prone. Situated in the deserts of western Rajasthan, floods in Barmer district
claimed over 150 lives.
“While it is true,” he says, “that the heavy rainfall is extremely rare in the region, it is
wrong to say that the event was unprecedented.” He backs it up with data: In the last 60
years, there have been five recorded instances of rainfall on a single day that exceeded
the current deluge. On September 1, 1968, 30.2cm rainfall was recorded, almost double
the 16cm rainfall which wreaked havoc in Barmer on August 22 this year.
According to Lal and other experts, besides heavy rains, there were two other factors
which caused such flooding: Barmer is a low-lying region and the surrounding areas also
experienced heavy rains. As a result, water runoff from these areas collected in Barmer.
Water runoff from underground reservoirs or anicuts also contributed to the inundation.
The other reason was the lack of any drainage for floodwater. Water couldn’t percolate
because 18-20 feet below the surface lay hard gypsum rock (commonly known as chuna).
In short, the experts say, what happened in Barmer was nothing out of the ordinary. To
call flooding in a drought-prone region as nothing unusual might be hard to swallow, but
meteorologists say that one has to look at the bigger picture. According to Nityanand
Singh of the Indian Institute of Tropical Meteorology, Pune, rainfall has been increasing
in the Rajasthan desert since 1973, though marginally. What has also made a difference is
the decreasing rain spells, not just in Rajasthan and in Punjab and Gujarat. As a result, the
intensity of showers is greater.
Singh recalls that there were heavy floods in Jodhpur in 1979 and 1981. He says that
given the trend of weather patterns, there could be floods in Rajasthan every third or
fourth year.
While climate experts are divided on the phenomenon of industrial emission-induced
global climate change, they are emphatic that one shouldn’t rush to associate the Barmer
floods as a sign of a major change in weather patterns in the near future.
Most experts see a connection between freak weather and global warming but some
disagree. But all of them admit that it is difficult to say anything about climate change
because it is a phenomenon that could happen over tens of thousands of years. Data over
the past 30 years or even, say, a couple of hundred years is not enough to conclude that
the climate of the planet and the Indian subcontinent is changing. Weather pattern
fluctuations that occur over a few decades are not unusual, after that they could reverse
themselves. A good example, Singh points out, is the mean global temperature pattern in
the last half-a-century or so.
It has gone up by 0.5 Celsius since 1941. But records show that mean global temperature
went down between 1941 and 1979, and there was global cooling in this period. “It is true
that co2 emissions have been on the rise since the 19th century, but we should also
remember that the capacity of the oceans to absorb co2 is 20 times that of the
atmosphere,” Singh says.
Suruchi Bhadwal, an associate fellow at The Energy Research Institute, strikes a
cautionary note. Extreme weather events around the globe are on the rise both in
frequency and intensity. And whatever the causes behind rising temperatures, the threat
to man is clear — the coastline of the Maldives has risen by 0.3mm, the Arctic snow is
melting, and there has been a major breach in the Antarctic ice shelf. There are
documented signs of major temperature changes closer home, Bhadwal says.
Prakash Rao of the World Wildlife Fund (WWF) cautions against linking climate change
to extreme weather events. The wwf station in Ladakh has been recording increasing
humidity and rainfall in this dry region. “There has been drought in Assam (normally
associated with heavy rainfall), for the first time in hundred years,” he says. “Cyclones in
the Bay of Bengal are also becoming stronger and more frequent.” But to link these freak
phenomena to climate change will require a lot more research, he cautions.
SK Dash, of the Centre for Atmospheric Sciences, iit Delhi, agrees that it would be
myopic to link the Barmer floods to climate change. There are model studies done over
200-300 year periods and the best a climatologist can do with this data is make “informed
projections”, he says.
When it comes to freak weather events that take a heavy toll on man, Lal reiterates that
“exceptional events while rare, can occur and do occur.”
Three days before the deluge in Barmer, Lal says (with a sense of relief and pride) the
Met department had predicted heavy rains in parts of western and eastern Rajasthan. All
of which makes the task of predicting climate change at present a matter of guesswork, or
at best, informed guesswork.