Predicting the monsoons - a risky proposition despite the deployment of satellites and supercomputers - appears to have become iffier thanks to climate change.
As the spectre of drought looms up across India thanks to this season's seriously deficient monsoon - so far - it looks as if the days when India's farming was referred to as a 'gamble with the monsoons' are returning.
"There is growing evidence to suggest that climate change is making the monsoons more unpredictable and worsening the severity of events like floods and droughts," Vinuta Gopal, energy and climate change campaigner for Greenpeace, told IPS.
Gopal says that while there is no scientific evidence yet to link this year's truant monsoon to climate change, what is clear is that the "modelling systems of the Indian Meteorological Department (IMD) cannot make predictions with any degree of accuracy." This means that farmers cannot depend on the forecasts to time sowing, harvesting and all that goes in between.
"Farmers we [Greenpeace] spoke with in the four southern states [Kerala, Tamil Nadu, Andhra Pradesh and Karnataka] told us that even traditional methods of forecasting have become undependable," Gopal said. "What is certain is that the intensity and frequency of storms and spells of rain and drought are becoming commonplace, but exactly how precipitation patterns are changing is still to be worked out."
On Apr. 17, IMD made an optimistic initial forecast for the South-West Monsoon that said that countrywide average cumulative rainfall for the season would be 96 percent of long-term average, allowing five percent either way for model error.
But this week India's Minister for Science and Technology Prithviraj Chauhan scaled that down to 93 percent of the 89 cm (35 inches) of rainfall that ought to fall in the June-September monsoon season - if major crops such as sugarcane, oilseeds and rice are not to suffer.
Chauhan's announcement brought gloom to a country hoping to make up for recessionary trends through a good harvest. Only a third of India's arable land is irrigated - with the rest depending on monsoon rainfall and on underground water pumped up from aquifers using bore wells.
The last time India suffered a drought was in 2002, when economic growth slumped to four percent, dramatically illustrating the impact of monsoons on the economy. The following year when India had the best rainfall in five years, the economic growth sprang back to 8.5 percent. In 2004, the rains were the second lowest in two decades and growth slowed to 6.9 percent. The nine percent growth India experienced in 2005 and 2007 was accompanied by normal rainfall during those years.
Pradhan Parth Sarthi, a climate scientist with the prestigious Energy Research Institute, told IPS that the Indian summer monsoon remains a "complex and mysterious phenomenon" and that it is a hard task for any meteorologist to predict its course and precipitation "through existing statistical and dynamical models."
"While climate change has little impact on average annual rainfall, going by rainfall data studied over a 100-year period, it is seen that during the monsoons heavy to very heavy rainfall is increasing in some areas and rainfall of lowered intensity is decreasing in other areas. These trends compensate each other in terms of net rainfall but they can be disruptive of normal agriculture," Sarthi said.
El Niño (abnormal rise in sea surface temperature over the equatorial central Pacific Ocean), one of several factors that can delay or cause a failure of the monsoons, seems to have caused a 50 percent reduction in normal rainfall in June, Sarthi said. "We are hoping that the situation will revive in July, the principal rainy season, when El Niño weakens over the central, equatorial Pacific Ocean."
"El Niño is already known to cause droughts and it will be fair to say that global warming may act to exacerbate these extreme events," Sarthi observed.
"Although it is impossible to predict the effects of global warming on the frequency of El Niños, all indications seem to be that they are becoming stronger, more common, and are no longer disappearing completely," says Kevin E. Trenberth, a lead author of the 2001 and 2007 United Nations Intergovernmental Panel on Climate Change (IPCC)'s scientific assessments of climate change. "In other words, the Pacific doesn't seem to be reverting to 'normal' anymore," Trenberth says in a report for the David Suzuki foundation.
For Gopal what is truly worrisome is a complacent attitude in which anomalous weather conditions are gradually becoming accepted as normal - and this despite a series of catastrophic events over the last few years.
In 2006, Cherrapunji in India's northeast - famed as the wettest place on earth - received considerably lower amounts of rainfall, whereas arid, desert states such as western Rajasthan received unusual amounts of rainfall, bringing in its wake all manner of calamities, including diseases.
The July 2005 Mumbai deluge wreaked havoc in the western metropolis, causing billions of dollars of damage and the loss of hundreds of lives. Surging floodwaters triggered by the 2002 monsoon killed more than 800 people in Bangladesh, India and Nepal and displaced millions. This year Cyclone Aila devastated coastal Bangladesh leaving over 24,000 people homeless, and destroying large tracts of mangrove forests.
"The intensity and frequency of freak spells of rain and drought, cyclones and storms are only getting worse by the year. Science increasingly suggests that climate change is going to change the pattern of the Indian monsoon," Gopal said.
After assessing historical data, the IPCC in its fourth assessment report in 2007 suggested that "warming in India is likely to be above the average for South Asia, with an increase in summer precipitation and an increase in the frequency of intense precipitation in some parts."
According to the IPCC the Indian monsoons are going to undergo gross changes as a direct result of climate change with increased rainfall in the summer monsoon, but with uneven distribution across India.
Gopal predicts climate change will likely to lead to a stronger but more variable monsoon until 2100. Thereafter, with the melting of the Greenland ice sheet and its effects on temperatures in the North Atlantic, and in turn, the pattern of the North Atlantic Ocean circulation, the grip on the monsoon will weaken.
"What is imminent and looming large are the dire consequences of a climate- changed monsoon," Gopal said.
Close to two-thirds of humanity live within regions influenced by the Asian monsoon and depend on the water that it brings to support agriculture, and supply potable water.
The Indian subcontinent lies close to the centre of the monsoonal region, and despite a gradual shift away from agriculture, India is still largely an agrarian state with agriculture accounting for a third of its Gross Domestic Product. Only about 40 percent of the land is irrigated - leaving farmers exposed to the vagaries of monsoons.
India's farming is focused on feeding domestic demand and follows the country's long-held policy of maintaining food self-sufficiency.
Original from:: http://www.ipsnews.net/news.asp?idnews=47395
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