American Geophysical Union
13 May 2013
AGU Release No. 13-20
For Immediate Release
Scientists find extensive glacial retreat in Mount Everest region
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Cancún, Mexico — Researchers taking a new look at the snow and ice covering Mount Everest and the national park that surrounds it are finding abundant evidence that the world’s tallest peak is shedding its frozen cloak. The scientists have also been studying temperature and precipitation trends in the area and found that the Everest region has been warming while snowfall has been declining since the early 1990s.
Members of the team conducting these studies will present their findings on May 14 at the Meeting of the Americas in Cancun, Mexico – a scientific conference organized and co-sponsored by the American Geophysical Union.
Glaciers in the Mount Everest region have shrunk by 13 percent in the last 50 years and the snowline has shifted upward by 180 meters (590 feet), according to Sudeep Thakuri, who is leading the research as part of his PhD graduate studies at the University of Milan in Italy.
Glaciers smaller than one square kilometer are disappearing the fastest and have experienced a 43 percent decrease in surface area since the 1960s. Because the glaciers are melting faster than they are replenished by ice and snow, they are revealing rocks and debris that were previously hidden deep under the ice. These debris-covered sections of the glaciers have increased by about 17 percent since the 1960s, according to Thakuri. The ends of the glaciers have also retreated by an average of 400 meters since 1962, his team found.
The researchers suspect that the decline of snow and ice in the Everest region is from human-generated greenhouse gases altering global climate. However, they have not yet established a firm connection between the mountains’ changes and climate change, Thakuri said.
He and his team determined the extent of glacial change on Everest and the surrounding 1,148 square kilometer (713 square mile) Sagarmatha National Park by compiling satellite imagery and topographic maps and reconstructing the glacial history. Their statistical analysis shows that the majority of the glaciers in the national park are retreating at an increasing rate, Thakuri said.
To evaluate the temperature and precipitation patterns in the area, Thakuri and his colleagues have been analyzing hydro-meteorological data from the Nepal Climate Observatory stations and Nepal’s Department of Hydrology and Meteorology. The researchers found that the Everest region has undergone a 0.6 degree Celsius (1.08 degrees Fahrenheit) increase in temperature and 100 millimeter (3.9 inches) decrease in precipitation during the pre-monsoon and winter months since 1992.
In subsequent research, Thakuri plans on exploring the climate-glacier relationship further with the aim of integrating the glaciological, hydrological and climatic data to understand the behavior of the hydrological cycle and future water availability.
“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 Intergovernmental Panel on Climate Change and the Water Research Institute-Italian National Research Council are funding this research.
Notes for Journalists
The researchers on this study of the Mount Everest region will present a poster about their work on Tuesday morning, 14 May 2013, at the Meeting of the Americas. The meeting is taking place from 14-17 May at the Cancún Center, located at Blvd. Kukulkan Km 9, Zona Hotelera, in Cancún, Mexico. For more information for members of the news media about the meeting, please go to http://moa.agu.org/2013/media-center/ or contact Sarah Charley, firstname.lastname@example.org, +1 (202) 777-7516.
Below is the abstract of the poster, which is being presented from 8:00 AM – 12:20 PM local Cancún time (Central Daylight Time, UTC/GMT – 5 hours), in the Gran Cancún Poster Hall (Cancún Center) as part of session C21B. “Cryosphere in a Warming Climate: Changes, Impacts, and Adaptation / Posters”
(Convener(s): Ninglian Wang (Chinese Academy of Sciences) and Mark Serreze (NSIDC)):
TITLE: Glacier response to climate trend and climate variability in Mt. Everest region (Nepal)
PRESENTATION TYPE: Assigned by Committee
CURRENT SECTION: Cryosphere (C)
CURRENT SESSION: C02. Cryosphere in a warming climate: Changes, Impacts and Adaptation
AUTHORS (FIRST NAME, LAST NAME): Sudeep Thakuri1, 2, Franco Salerno2, 3, Nicolas Guyennon2, Gaetano Viviano2, 3, Claudio Smiraglia1, 3, Carlo D’Agata1, Gianni Tartari2, 3
INSTITUTIONS (ALL): 1. Graduate School of Earth, Environment and Biodiversity, University of Milan, Milan, MB, Italy.
2. Water Research Institute, National Research Council , Brugherio, MB, Italy.
3. Ev-K2-CNR Committee, Bergamo, BG, Italy.
ABSTRACT BODY: This study is conducted with the aim of coupling the climatic dynamics with glaciers variations. The glaciers in the Mt. Everest region in Nepal Himalaya are characterized by the debris-mantle in most of their ablation zone and are controlled by the south-Asian summer monsoon and precipitation due to mid-latitude westerly. We analyzed variations in glacier surface and snowline altitude for the glaciers/ice mass in the Sagarmatha (Mt. Everest) National Park (area: 1148 km2), using cartography and remote imaging since 1950s to 2011 and uncertainties associated, providing a longest time series of glacier variations in this region. The glacier surface area had loss of 14.3±5.9 % (0.27 % yr-1) from 396.2 km2 to 339.5 km2 in 1958 to 2011 with the loss by 0.12 % yr-1 in 1958-75 and 0.70 % yr-1 in recent years. The smaller glaciers with <1 km2 dimension had decreased by 43% in their surface area showing rapid disappearance of very small glacier/ice mass. The accumulation area decreased by 24.8%, whist ablation area increased by 17.7 % with nearly 6% increase in debris-cover surface in ablation zone in 1958 to 2011. The accumulation and ablation area changes can be explained by SLA position which was continuously moving upward from 5279±144 m asl. in 1958 to 5472±209 m asl. in 2011 with the overall vertical shift of 192±9 m (3.6 m yr-1). The glaciers are showing the discordant behavior with individual glaciers varying spatially and temporally discern manner. Majority of glaciers are retreating but some glaciers observed as stationary or even advancing in certain period of analysis which could be explained by their location and topographic effect. We reconstructed temperature and precipitation complete series using the monthly quantile mapping and expectation maximization techniques from the all available insitu measurements in 1992-2011 from different automatic weather stations located in the Mt. Everest region and conducted the singular spectral analysis and monthly sequential Mann-Kendall test. The analysis indicated that annual temperature has increased by +0.03°C yr-1 with the increase in winter and pre-monsoon months but statistically significant only for winter months. The precipitation has decreased by around 180 mm in the analyzed period. The decreases in precipitation are statistically significant for both winter and summer precipitation. The stream-flow data indicates significantly widening of annual extreme discharge characteristics. Another, the longest time series of temperature and precipitation from the closest meteorological station (Kathmandu) also agree with this observation, indicating significant increase in temperature (1960s-2011) while the precipitation has statistically no significant trend until 1990s but significantly weakening trend in 1990s to 2011. We conclude by underlining that the observed variation of glacier surface and SLA could be explained jointly by increase of temperature and more importantly, by changes of precipitation for recent years as the glaciers in this region are controlled by summer-monsoon precipitation.
Image caption and credit:
A new study finds a decline in snow and ice on Mount Everest (second peak from left) and the national park surrounding it. Credit: Pavel Novak
Contact information for the researchers:
Sudeep Thakuri: Email, email@example.com