Climate change may be baring Mount Everest
NEPAL: A warming climate is melting the glaciers of Mount
Everest, shrinking the frozen cloak of Earth’s highest peak by 13% in
the last 50 years, researchers have found.
Rocks and natural debris previously covered by snow are appearing now
as the snow line has retreated 590 feet, according to Sudeep Thakuri, a
University of Milan scientist who led the research.
The pessimistic view of Earth’s tallest peak was presented during a
meeting Tuesday of the American Geophysical Union in Cancun, Mexico.
Researchers said they believe the observed changes could be due to
human-generated greenhouse gases altering global climate, although their
research has not established a firm connection.
The team reconstructed the glacial history of the area using
satellite imagery and topographic maps of Everest and the surrounding
713-square-mile Sagarmatha National Park. Their statistical analysis
shows that the majority of the glaciers in the national park are
retreating at an increasing rate, Thakuri said.
Small glaciers of less than a square kilometre (about 247 acres), are
vanishing fastest, registering a 43% decline in surface area since the
1960s.
Average temperatures have risen about one degree Fahrenheit since
1992, according data from the Nepal Climate Observatory stations and
Nepal’s Department of Hydrology and Meteorology, the researchers found.
Since 1992, precipitation has declined nearly four inches during the
pre-monsoon and winter months, they found.
“The Himalayan glaciers and ice caps are considered a water tower for
Asia since they store and supply water downstream during the dry
season,” said Thakuri. “Downstream populations are dependent on the melt
water for agriculture, drinking and power production.” The topic of
glacial melt in the Himalayas has been controversial. Initial reports by
the Intergovernmental Panel on Climate Change predicted glaciers in the
region would disappear by 2035. Subsequent analysis by the Gravity
Recovery and Climate Experiment (GRACE) satellite mission showed that
the melt was one-tenth the reported rate, and that some areas were
experiencing growth, particularly in the Tibetan plateau.
Research published last year, however, showed that glaciers have been
retreating over a 30-year period on the Tibetan plateau. It also showed
that areas that depend on snow during regional monsoon seasons are
particularly vulnerable to small rises in temperature.
The plateau is of concern because it is the ultimate source of
drinking and irrigation water for more than one billion people in Asia.
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