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Global Warming: Over 70 per cent of Everest glacier’s volume may be lost by 2100

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New Delhi: Over 70 per cent of the glacier volume in the Mount Everest region in the Himalayas could be lost in 85 years if greenhouse gas emissions continue to rise, a new paper suggests. It also indicates more flood risk in the future in the Kosi river downstream from Nepal to India.

The paper, “Modelling glacier change in the Everest region, Nepal Himalaya”, published on Wednesday in The Cryosphere, a journal of the European Geosciences Union (EGU), said the glacier volume could be reduced between 70 and 99 percent by 2100.

It is a first approximation to how the Himalayan glaciers will react to increasing temperatures in the region. The results depend on how much greenhouse gas emissions continue to rise and on how this will affect temperature, snowfall and rainfall in the area.

A team of researchers from Nepal, France and the Netherlands have found the Everest glaciers could be very sensitive to future warming and that sustained ice loss through the 21st century is likely.

If greenhouse gas emissions continue to rise, the glaciers could experience dramatic change in the decades to come, said the study.

“The signal of future glacier change in the region is clear: continued and possibly accelerated mass loss from glaciers is likely given the projected increase in temperatures,” said Joseph Shea, a glacier hydrologist at the International Centre for Integrated Mountain Development (ICIMOD) in Kathmandu.

“Our results indicate that these glaciers may be highly sensitive to changes in temperature and that increases in precipitation are not enough to offset the increased melt,” Shea said.

Increased temperatures will not only increase the rates of snow and ice melt but can also result in a change of precipitation from snow to rain at critical elevations, where glaciers are concentrated. Together, these act to reduce glacier growth and increase the area exposed to melt, said the leader of the study.

The researchers studied glaciers in the Dudh Kosi basin in the Nepal Himalayas, which are home to some of the world’s highest mountain peaks, including Mt Everest, and to over 400 sq km of glacier area.

“Apart from the significance of the region, glaciers in the Dudh Kosi basin contribute meltwater to the Kosi river, and glacier changes will affect river flows downstream,” Shea said.

Changes in glacier volume can impact the availability of water, with consequences for agriculture and hydropower generation.

While increased glacier melt initially increases water flows, ongoing retreat leads to reduced meltwater from the glaciers during the warmer months, with greatest impact for the local populations before the monsoon when rainfall is scarce, said the paper.

Glacier retreat can also result in the formation and growth of lakes dammed by glacial debris. Avalanches and earthquakes can breach the dams, causing catastrophic floods that can result in river flows 100 times greater than normal in the Kosi basin.

The Kosi river is known as the “sorrow of Bihar” as it has caused widespread damage in the past due to flooding and frequent change in its course.

To find out how glaciers in the region will evolve in the future, the researchers started by using field observations and data from local weather stations to calibrate and test a model of glacier change over the past 50 years.

“To examine the sensitivity of modelled glaciers to future climate change, we applied eight temperature and precipitation scenarios to the historical temperature and precipitation data and tracked how glacier areas and volumes responded,” said study co-author Walter Immerzeel of Utrecht University in the Netherlands.

“Our estimates need to be taken very cautiously, as considerable uncertainties remain,” said Patrick Wagnon, a glaciologist at the L’Institut de Recherche pour le Developpement in Grenoble in France.

The paper stresses that “the signal of future glacier change in the region is clear and compelling” and that decreases in ice thickness and extent are expected for “even the most conservative climate change scenario”.

-IANS

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Fear of Leprosy Resurgence in Nepal

There are only three staff working in the leprosy section and the same team looks after the disability programme, as well, he told the newspaper

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Leprosy, Wikimedia

Health officials in Nepal fear leprosy resurgence in the country with prevalence rate reaching 0.94 per cent in 2018.

Leprosy-free status was given to the Himalayan nation after it declared elimination of the disease in 2009. However, that status could be lost if prevalence rate reaches one per cent of total population, Kathmandu Post reported on Thursday.

Experts already fear that this marks the resurgence of the disease in Nepal. The percentage could be more, an official said, as the current given figures have been derived just from preliminary data.

The Leprosy Control and Disability (LCD) section of Epidemiology and Disease Control Division (EDCD) of Department of Health Services said that the prevalence rate was 0.92 and 0.89 in 2017 and 2016, respectively, the news report said.

“It will be a great setback for the country if it loses the status,” said Rabindra Baskota, a doctor and chief of the LCD section.

Incubation period of leprosy varies from one to 20 years and diagnosis of more patients could help stop the further spread of the disease, according to him.

An amputated leg, claw toes and claw hands of leprosy patient Gopal Bag are seen at the Leprosy Mission Trust India hospital. Kolkata. VOA

“It will take only a couple of years to reach one percent if this upward trend continues,” he added.

The prevalence rate is over one per cent in various districts of the Tarai region, Baskota said, adding that the country had received the leprosy eliminated status, after reducing its prevalence rate by 0.77 per cent, in 2009.

Sishir Silwal, a focal person for the leprosy control programme in Gulmi district, said regular review meetings for leprosy, which should be held every four months, has not been held for the last eight months.

Also Read- Poor Cognitive Function Raises Bad Oral Health in Elderly

Kathmandu Post quoted Bibek Kumar Lal, Director at EDCD, as saying that there is a severe crunch in manpower that hinders proper functioning.

There are only three staff working in the leprosy section and the same team looks after the disability programme, as well, he told the newspaper.

Leprosy, a chronic infectious disease caused by Mycobacterium leprae, is transmitted through nasal secretion or from droplets from the mouth. It affects the skin, peripheral nerves and eyes, leading to disfigurement and nerve damage. The disease is curable with a multi-drug therapy. (IANS)