The view that the upper Indus glaciers are ‘disappearing’ quickly and will be gone in 30 years is mistaken. “There is no evidence to support this view and, indeed, rates of retreat have been less in the past 30 years than the previous 60 years
By Maliha Nishan Iqbal
FOR CENTURIES, glaciers have inspired awe and wonder. The idea that human assault might ever triumph over such powerful features of our natural landscape seemed almost unimaginable. But now climate change is disrupting the ecological balance of the Tibetan Plateau and the mighty glaciers of the Himalaya are, in fact, disappearing.
Glacial ice can range in age from several hundred to several hundreds of thousands years, making it valuable for climate research. To see a long-term climate record multiple ice cores are drilled and extracted from the glacier, these cores are continuously providing record to scientists with information regarding past climate. Scientists analyze various components of cores, particularly trapped air bubbles, which reveal past atmospheric composition, temperature variations, and types of vegetation. Glaciers literally preserve bits of atmosphere from thousands of years ago in these tiny air bubbles. This is how scientists know that there have been several Ice Ages. Past eras can be reconstructed, showing how and why climate changed, and how it might change in the future.
Scientists are also finding that glaciers reveal clues about global warming. How much does our atmosphere naturally warm up between Ice Ages? How does human activity affect climate? Glaciers are so sensitive to temperature fluctuations which accompanying climate change. Direct glacier observation may help answer these questions. Since the early twentieth century, with few exceptions, glaciers around the world have been retreating at unprecedented rates. Some scientists attribute this massive glacial retreat to the Industrial Revolution, which began around 1760. In fact, some ice caps, glaciers and even an ice shelf have disappeared altogether in this century. Many more are retreating so rapidly that they may vanish within a matter of decades.
The 1991 discovery of the 5,000 year-old "ice man," preserved in a glacier in the European Alps, fascinated the world. Tragically, this also means that this glacier is retreating farther now than it has in 5,000 years, and no doubt other glaciers are as well. Scientists, still trying to piece together all of the data they are collecting, to find out whether human-induced global warming is tipping the delicate balance of the world's glaciers or not.
The Intergovernmental Panel on Climate Change's (IPCC) report claims that “Himalayan glaciers are receding faster than in any other part of the world and, if the present rate continues, the likelihood of them disappearing by the year 2035 and perhaps sooner is very high if the Earth keeps warming at the current rate.”
However, glaciologists find such figures inherently ludicrous, pointing out that most Himalayan glaciers are hundreds of feet thick and could not melt fast enough to vanish by 2035 unless there was a huge Global temperature rise. The maximum rate of decline in thickness seen in glaciers at the moment is 2-3 feet a year and most are far lower. A new report by a senior Indian glaciologist states that the glaciers remain frozen and quite intact.
Glaciologists analyzed remote-sensing satellite data or conducted on-site surveys at remote locations often higher than 5000 meters. While the report surveyed of a number of glaciers, two particularly iconic ones stand out. The first is the 30-kilometer-long Gangotri glacier, source of the Ganges River. Between 1934 and 2003, the glacier retreated an average of 70 feet (22 meters) a year and shed a total of 5% of its length. In 2004 and 2005, the retreat slowed to about 12 meters a year, and since September 2007 Gangotri has been “practically at a standstill,” according to the report. The second glacier, the Siachin glacier in Kashmir, is even more stable. Claims reported in the media that Siachin has shrunk as much as 50% are simply wrong. A report notes that the glacier has “not shown any remarkable retreat in the last 50 years.” These conclusions were based in part on field measurements by ecologist of the G. B. Pant Institute of Himalayan Environment and Development in Almora. Much like the hysteria about Greenland's ice cap, it seems reports of the glaciers' demise are a bit premature.
According to a report many glaciers in the Karakoram Mountains, on the border of India and Pakistan, have stabilized or undergone an aggressive advance. Kenneth Hewitt, a glaciologist at Wilfrid Laurier University in Waterloo, Canada, says that he observed five glacier advances and a single retreat in the Karakoram. Such evidence challenge the view that the upper Indus glaciers are ‘disappearing’ quickly and will be gone in 30 years is seems mistaken. “There is no evidence to support this view and, indeed, rates of retreat have been less in the past 30 years than the previous 60 years,” Hewitt says.
Other researchers and noted experts have raised their voices in support of above; the only possible conclusion is that IPCC's Himalaya assessment got it “horribly wrong.” The University of Nebraska researcher adds, “They were too quick to jump to conclusions on too little data.”
Data indicates Ganges results primarily from monsoon rainfall, and until the monsoon fails completely, there will be a Ganges river, very similar to the present river.” Glacier melt contributes only 3 to 4 percent of the Ganges's annual flow. Even when faced with data showing the errors in their work, the IPCC seems incapable of admitting they were wrong. Unfortunately for the climate change alarmists the truth is out, the glaciers of the Himalayas remain safely frozen and won't be disappearing anytime soon.
http://www.technologytimes.pk/mag/2011/jan11/issue03/is_climate_change_affect.php
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