Open magazine, 27 Nov, 2009
First, a disclaimer: this article does not intend to make the reader doubt the dangers of global warming. It intends to go a little further.Second, an admission: it is never easy to approach any ‘gospel truth’ with facts and reason. Ask Dr Mitchell Taylor.
One of the most startling advertisements of climate change is that global warming has made life difficult for polar bears and will wipe out two-thirds of their population in the next 50 years. In 2002, however, a USA Geological survey of Wildlife noted that polar bear populations ‘may now be near historic highs’. More recently, the US Fish and Wildlife Service recorded that that there were 20,000-25,000 polar bears, up from 5,000-10,000 estimated in the 1950s and 1960s.
Those reports did not make news. But then, Dr Taylor, one of the planet’s most experienced Arctic biologists who has been following polar bears for three decades, happily—and inconveniently— reported that of the 19 different polar bear populations, almost all were at optimum levels or increasing; only two have for local reasons modestly declined. Even the southern less ice region of the Davis Strait, Dr Taylor noted, ‘is crawling with polar bears. It’s not safe to camp there. They’re fat. The mothers have cubs. The cubs are in good shape.’
The result of his report? Dr Taylor was barred from the much-hyped meeting of the Polar Bear Specialist Group (PBSG), set up under the IUCN Species Survival Commission, held in July this year at Copenhagen, because his views running ‘counter to human-induced climate change are extremely unhelpful’.
Covered with much fanfare by the media, the PBSG meet ‘renewed the conclusion from previous meetings that the greatest challenge to conservation of polar bears is…climatic warming’. The ban on Dr Taylor, and his field observations, went largely unreported.
THE MYTHDr Taylor was not the only one doubting the theory of man-made global warming or its impact.
The United Nations Intergovernmental Panel on Climate Change (IPCC) report of 2007 (fourth assessment) authored by 52 scientists, claimed a scientific consensus on its findings that increasing emission of greenhouse gases due to human activities had already triggered a dangerous trend of global warming and unless emission levels were controlled, the trend would soon lead to rapid melting of snow and ice, causing rivers to dry up and coastal areas to disappear under a rising sea.
But so far, at least 650 scientists from around the world have questioned the report’s findings. Dissent has always been there. According to a survey of 530 climate scientists in 27 countries, conducted in 2003 by Dennis Bray and Hans von Storch at the GKSS Institute of Coastal Research in Germany, 82 per cent said global warming was happening, 56 per cent said it was mostly caused by human activities, and only 35 per cent said models could accurately predict future climate conditions.
More recently, a study published in Energy and Environment in 2008 found that of a total 528 papers on climate change (2004-2007), only one paper made any reference to climate change leading to catastrophic results. While 32 papers rejected the IPCC consensus outright, 263 did not commit either way.
Of course, there is a consensus that the climate is changing. Climate is determined by averaging weather variables over an extended period and has been changing ever since the earth has been turning. And, nobody denies that the earth’s resources are getting increasingly stretched due to spiralling population and human development. So, leave alone science, the common sense way forward is to adopt environmentally sustainable economies and lifestyles.
But forced to acknowledge climate change as the biggest threat facing mankind, the scientific fraternity has been raising three fundamental questions. Is the global climate really warming up? If so, is the change due to human activities (greenhouse gas emissions) and can it be controlled by human intervention (reduction in emissions)? Are the alarming forecasts of imminent tipping points realistic?
• A number of scientists deny any evidence of any unnatural or significant rise in global temperature. For example, they refer to the Nasa Giss data that show how the South Pole winter (June-August) has cooled about 1 degree Fahrenheit since 1957 and the coldest year was 2004. Nasa itself, after hyping the year 1998 as the hottest in US history, eventually accepted a data error and corrected the record to 1934 as the hottest year.
According to these sceptics, while bandying about the lowest ice extent since satellite monitoring began in 1979 in the Arctic, climate activists gloss over the fact that the Southern Hemisphere, Antarctica, has set a new record for maximum ice extent. Since 1979, the trend has been progressively upwards for the total Antarctic ice extent, with a number of new records set over the past 15 years.
Some, like Philip Stott, professor emeritus of biogeography at the University of London, argue that historically, there have been sharp rises in temperature over very short periods. In 1200 AD, Europe was 2 degrees centigrade warmer than it is today and agriculture flourished even in Greenland.
• Many agree that the climate has been showing a warmer trend but maintain that there is no scientific evidence to prove that the warming is man-made or it can be controlled by reducing GHG emissions.
Some of them, like Sallie Baliunas and Willie Soon of the Harvard-Smithsonian Center for Astrophysics, blame solar activities, and not GH gases, for the warming trend.
Others, like Luc Debontridder of Brussels’ Royal Meteorological Institute or Professor Geoffrey G Duffy of the University of Auckland, maintain that water vapour and water condensed on particles as clouds have a much greater greenhouse impact than carbon dioxide (CO2). Incidentally, atmospheric water vapour is not anthropogenic, its formation and dynamics are independent of human activities.
• The scientific fraternity is most critical when it comes to random doomsday predictions. Mike Hulme, head of the EU integrated project Adam (Adaptation and Mitigation Strategies), recently blamed alarmist tendencies for “complicating things with climate change myths” by linking everything—from hurricane Katrina to Mumbai rains—to global warming. He slammed movies like The Day After Tomorrow and Age of Stupid for exaggerating threats of climate change.Back home, not too long ago, the country’s most prominent climate expert appeared on a news channel to support the theory that global warming was behind the melting of the ice Shiva Lingam (stalagmite formation) at Amarnath. He looked more angry than embarrassed when reminded that the stalagmites in the neighbouring caves were in good health because they did not have to suffer the temperature rise caused by too many jostling devotees.
Unfortunately, the IPCC itself triggered this alarmist trend. So much so that in the final draft of the fourth assessment report released in 2007, the panel had to revise its exaggerated predictions made in 2001 and reduce the overall estimate of the effects of global warming by 25 per cent.
THE SCARE
For India, the most dramatic climate forecast is that the Gangotri glacier will disappear by 2035, reducing the Ganga to a seasonal river.
The recent report on Himalayan glaciers by Dr VK Raina, a former deputy director general of the Geological Survey of India, found it ‘premature to make a statement that glaciers in the Himalayas are retreating abnormally because of global warming’. On Gangotri, the report said that the glacier had been retreating rapidly at about 20 metres per year until 2000, but has since slowed down considerably, and practically remained standstill since September 2007.
“Data generated from the Himalayas over the last 100 years indicate that the glaciers have been retreating continuously, barring a flip here and there. But the rate of retreat has not been alarming or unnatural, especially in the last decade or so. There is nothing to support claims that these glaciers, including Gangotri, will disappear in the next few decades,” maintains Dr Raina.
In a paper published in Current Science last year, Dr Sharad Jain, a professor at the Indian Institute of Technology, Roorkee, pointed out that even if the annual recession rate of the Gangotri glacier reaches 40 metres – which is double the current rate—a glacier that measures 30 km in length will take about 700 years to melt away.
“It was a rather simplistic way to explain the improbability of the glacier disappearing in the near future. After considering nonlinearities and to make a conservative estimate, the time-span could be assumed to be hundreds of years. If the snout of the Gangotri glacier was indeed at the Gangotri temple about 4,000 years ago, its retreat over four millennia has been just 18 km,” explains Dr Jain.
Even if we assume that the Gangotri glacier is in real danger of melting away, will it make the Ganga a seasonal river?
Three rivers—the Chambal, Ken and Betwa—contribute to the Ganga through the Yamuna. In Bihar, four mighty rivers—the Ghaghara, Gandak, Kosi and Sone—join in. Together, these tributaries bring enough water to make the Ganga’s flow at downstream Patna almost 17 times its flow at upstream Devprayag. But even in the headwaters region, the Ganga depends only partially on the Gangotri glacier for water. As Dr Jain points out, snow and glacier melting contribute only 29 per cent to the annual flow at Devprayag; the rest is from rainwater. More than 70 per cent of the flow at Haridwar is due to rainfall and beyond Haridwar, the influence of the Gangotri glacier on river flow becomes progressively less—at Allahabad, it is less than 4 per cent.
“Most of the Ganga’s catchment is rain fed. Even during the lean season, there is enough baseflow (discharge derived from groundwater sources), particularly downstream Haridwar. Glaciers or no glaciers, the Ganga will remain a perennial river as long as groundwater tables are intact,” claims Professor I B Singh, an authority on the Ganga and a veteran geologist with Lucknow University.
The other perceived threat of global warming—rising sea levels leading to erosion, salinity and inundation—has unsettled many in India, particularly along its 8,000-km-long coastline.While a significant rise in sea levels and subsequent inundation still remain only a possibility, increasing salinity and rapid erosion are already making lives miserable for much of India’s coastal population. But can these trends be attributed to climate change?
“Over the last 2,000 years, many rapid warming and cooling episodes occurred on 100-year scales. This has resulted in the rise and fall of sea levels. The threat perception on account of sea level rise is less compared to the other factors,” says Dr TN Prakash, a senior scientist at the Centre for Earth Science Studies, Thiruvananthapuram.
According to Dr Prakash, coastal erosion is a natural, seasonal phenomenon. But the impact is being felt more severely in recent years due to destruction of protective mangrove covers and reduced sediment discharge by rivers. Other human factors, like rampant beach mining, also add to the problem. As recently as the Asian tsunami of 26 December 2004, mangroves acted as a buffer in a number of stretches along the coastline. Without the effective bio-fencing of mangrove cover or dune vegetation, coastlines are increasingly getting exposed to erosion.
A free-flowing river gathers sediments as it meanders inland and deposits the load when it reaches the sea. This sediment load compensates for much of coastal erosion. But when a dam is built on a river to brake its flow, the river’s sediment load settles down in the dam’s reservoir.
Globally, more than 50,000 large dams are in operation today. At least 100 billion tonnes of sediment has been retained in these reservoirs in the past 50 years, causing significant reduction in the flux of sediment to coasts. From Egypt (Nile river delta) to Morocco (Moulouya wetlands) to Louisiana (Mississippi river delta), big dams exacerbate coastal erosion across the world.
Too many dams on rivers also mean that too little water reaches deltas. This, in effect, results in limited percolation to coastal aquifers. Also, restricted river flow forces coastal people to extract more and more groundwater, already under severe pressure due to a spurt in population along the coasts. It is this low-recharge-high-extraction scenario (not any perceived rise in sea levels) that is making coastal aquifers vulnerable to seawater ingress.
“There is need for reorientation in our thinking. We should ensure better management of water resources instead of worrying about climate change over which we anyway have no control. By extracting too much groundwater, constructing big dams and allowing effluents to enter the water system, we have created a water crisis that poses a far greater challenge,” says Dr BP Radhakrishna, former president of the Geological Society of India, Bangalore.
THE BLINDSPOTIf you are taken in by the apocalypse scenario of a future water catastrophe caused by glacier meltdowns and rise in sea levels, you had better figure out how severe a water crisis is facing us right now.
Consider these:
• By 2015 all countries, except Canada and Scandinavian nations, will suffer water shortage in at least a part of their territory. If present trends continue, according to the UN Water Report of 2007, 1.8 billion people will be living in countries or regions with absolute water scarcity by 2025, and two-thirds of the world population will face water stress.
• Such water scarcity will also jeopardise our food security. Agriculture and animal husbandry are water intensive processes. It takes a litre of water to produce food worth one calorie of energy. So, to satisfy the need of 3,000 calories per person for a population of 6.5 billion on earth, our daily requirement of water is equivalent to a water body that is 1 metre deep, 1 kilometre wide and 7 million kilometre long—long enough to encircle the earth 180 times.
• Already, in parts of the world such as West Asia, the Indo-Gangetic Plain, the North China Plain and the High Plains in North America, human water use has exceeded average annual water replenishment. With 60 per cent of the global population and just 36 per cent of the earth’s available freshwater share, Asia faces the grimmest crisis.
• An analysis of Nasa satellite data published in Nature this August shows that the groundwater level has been going down by 33 cm per year in India’s northern plane (Rajasthan, Punjab, Haryana and Delhi) over the past decade due to over extraction.
Indeed, if we trace the growth of our so-called ecological footprint, water emerges the biggest casualty. While the world’s population increased by 300 per cent in the 20th century, the use of water increased by a staggering 700 per cent. Over a longer period of 250 years since the Industrial Revolution, carbon dioxide formulations in the atmosphere have gone up by approximately 37 per cent, methane by 150 per cent and nitrous oxide by 16 per cent.
But does our water security depend on climate change? The IPCC report does offer projections of how global warming will impact groundwater and rainfall patterns, but the latest UN World Water Development Report of 2009 notes that ‘these impacts are likely to be small (and possibly negligible) compared with the stresses placed on groundwater systems by current socio-economic drivers’.
Besides causing groundwater depletion, these socio-economic drivers have also triggered a problem of contamination. Already, 1.7 billion people lack access to safe water in developing countries. In India and Bangladesh, more than 500 million people are living in an arsenic affected area of 600,000 sq km in the Ganga-Meghna-Brahmaputra plain. In India alone, at least 62 million people, including 14 million children, are suffering from fluorosis.
“If we compare the total amount of available water on earth to a water bottle containing 18 litres of water, the available surface freshwater is only three teaspoons. This puts enormous pressure on the groundwater stock which is again less than 1 per cent of the earth’s total water. We are taking little care of this priceless reserve. Groundwater arsenic and fluoride contamination in developing countries could be more serious than any human tragedy known to mankind,” warns Dr Dipankar Chakraborti, director, School of Environmental Studies, Kolkata.
The major water contaminants created by human activities are microbial pathogens, nutrients, pesticides, oxygen-consuming substances, heavy metals and persistent organic matter. These pollutants enter water systems through agricultural run-off, domestic and industrial effluents and inadequately treated wastewater discharge, erosion, mine and landfill leachate, litter disposal etcetera. Every aspect of our lifestyle and economy endangers the water sources we live on.
Sample these:
• Approximately 2 million tonnes of human waste is released annually into rivers and streams around the globe.
• It is estimated that 90,000 to 100,000 chemicals are in regular use; many of them toxic.
• In the US alone, industries produce more than 36 billion kg hazardous organic chemical-based pollutants every year, and only 10 per cent of this is being disposed of in an environmentally responsible manner.
• Projected increases in fertiliser use for food production over the next three decades suggest that there will be a 10–20 per cent global increase in river nitrogen flows.
“These are not computer-simulated trends. These are real, hard data. While climate change is natural, the hype over it is political. This din diverts our attention from pollution, the biggest man-made disaster,” says Dr Arun D Ahluwalia, director, Centre of Advanced Studies in Geology, Punjab University, Chandigarh.
Five years back, water scientists Michel Meybeck and Charles Vörösmarty warned that “the global impacts of human interventions in the water cycle…are likely to surpass those of recent or anticipated climate change, at least over decades.”
Granted, the UN declared 2005–2015 the International Decade for Action (Water for Life), ‘to enhance international cooperation in addressing the exploitation and degradation of water resources’. But even after half a decade, there is hardly any effective move for inter-governmental agreements to protect trans-boundary freshwater systems, or a commitment to cut down on use of pesticides and toxins that poison water worldwide. The world has been too busy fighting the perceived threats of global warming.
THE BOTTOMLINEBut even if the climate change debate is far from over, shouldn’t we anyway try to reduce air pollution? Won’t the mitigation methods prescribed to fight global warming anyway help the environment?
Yes, we should cut down emissions by all means. But we should set ourselves realistic targets. Pushing for high targets will always delay a global consensus. More importantly, reducing emissions requires making compromises – both individual (lifestyle) and economic. Since we and our economy can make only that much compromise at a time, higher emission targets may not leave room to set effective targets for reducing water usage or regulating contamination.
And, no, not all prescriptions to fight climate change are necessarily healthy. We should not encourage bio-fuel or jatropha cultivation, without assessing how it will affect our food security on a planet of finite land and water resources. We should not promote plantation of fast-growing trees, particularly in areas where rootstocks can bounce back, without assessing how monocultures damage soil quality and biodiversity. But yes, we should start asking questions.
A few years back, Professor Stott described the “climate angst” as “each successive generation’s craving for its own Noah myth”. Today, few remember the scare of global cooling in the early 1970s when alarmists started predicting the imminent collapse of the world. That climate hysteria lasted for about two decades till, in the late 80s, it was time for global warming.
Copenhagen 2009 comes two decades after the IPCC was established in 1988 and released its first report in 1990. With no real deal in sight (see next post below), perhaps it is time for the pundits to move on to the next climate scare.
Meanwhile, you may still refuse to go with the flow. The world may yet avoid water wars.
Mazoomdaar is an independent journalist and filmmaker
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