This retreat impacts water supplies to millions of people, increases the likelihood of outburst floods that threaten life and property in nearby areas, and contributes to sea-level rise.
From the Caucasus to the Himalayas, these changes are being measured. Here is a panoramic photographic mosaic of several glaciers on the northern slope of Gora Elbrus, a volcanic massif in the Central Caucasus Mountains. The photographic survey was done by N. Nikulin in 1957 during the International Geophysical Year. Today, virtually all of these glaciers have disappeared.Photograph courtesy of V.M. Kotlyakov, Russian Academy of Sciences, Moscow.
The U.S. Geological Survey, in collaboration with 39 international scientists, published a report on the status of glaciers throughout all of Asia, including Russia, China, India, Nepal, Bhutan, Pakistan, Afghanistan, Georgia, Kyrgyzstan, Tajikistan, and Kazakhstan.
“Of particular interest are the Himalaya, where glacier behavior impacts the quality of life of tens of millions of people,” said USGS scientist Jane Ferrigno. “Glaciers in the Himalaya are a major source of fresh water and supply meltwater to all of the rivers in northern India.”
As glaciers become smaller, water runoff decreases, which is especially important during the dry season when other water sources are limited. Climate change also brings warmer temperatures and earlier water runoff from glaciers, and this combined with spring and summer rains can result in flood conditions. The overall glacier retreat and additional melt can increase the amount of water dammed in the vicinity of a glacier, and the added pressure enhances the likelihood of disastrous outburst flooding.
Talgar Peak in the Tienshan mountains, Kazakustan . Photo: Bob McKerrow
While most glaciers in Asia are in recession, some glaciers have been found to advance. Some of the advancing glaciers are surge-type glaciers, which move forward more rapidly than average in a short period of time. The reason for this is being studied by glaciologists, and is likely due to unique and local condition
Glacier studies in each area started at different times depending on accessibility of glaciers and scientific interest. For example, the earliest description of glaciers in China was in 630 A.D., while studies in the Caucasus area of Russia began in the mid 1800s and modern studies in Nepal started in the 1950s.
The time period for retreat also differs among each glacier. In Bhutan, 66 glaciers have decreased 8.1 percent over the last 30 years. Rapid changes in the Himalaya is shown in India by the 12 percent retreat of Chhota Shigri Glacier during the last 13 years, as well as retreat of the Gangotri Glacier since 1780, with 12 percent shrinkage of the main stem in the last 16 years.
Looking up the Spiti Valley to the high Pir Panjal mountains. Photo: Bob McKerrow
Glaciers in Russia and in the four republics once part of the Former Soviet Union have the largest area of glaciers in Asia, covering 30,478 square miles, which is about the size of South Carolina. The glaciers of China have the second largest area of glaciers in Asia, covering 22,944 square miles, which is about twice the size of Massachusetts. In Afghanistan, the more than 3,000 small mountain glaciers that occur in the Hindu Kush and Pamir mountains provide vital water resources to the region.
Glacier in the Pamir mountains: Photo: Bob McKerrow
“This report was a collaboration between U.S. and foreign authors, the most knowledgeable glaciologists for each geographic region covered,” said USGS scientist Richard S. Williams, Jr. “The USGS published historical and modern data authored by local experts. Some analyses of past climate conditions were conducted by studying ice cores from high-mountain areas of Asia.”
This report is the 9th in the series of 11 volumes to be published as the USGS Satellite Image Atlas of Glaciers of the World. You can view other publications in this series online.
If you would like further information you can click on the link below or read the preface to Glaciers of Asia posted below.
Glaciers of Asia
Edited by Richard S. Williams, Jr., and Jane G. Ferrigno
This chapter is the ninth to be released in U.S. Geological Survey Professional Paper 1386, Satellite Image Atlas of Glaciers of the World, a series of 11 chapters. In each of the geographic area chapters, remotely sensed images, primarily from the Landsat 1, 2, and 3 series of spacecraft, are used to analyze the specific glacierized region of our planet under consideration and to monitor glacier changes. Landsat images, acquired primarily during the middle to late 1970s and early 1980s, were used by an international team of glaciologists and other scientists to study various geographic regions and (or) to discuss related glaciological topics. In each glacierized geographic region, the present areal distribution of glaciers is compared, wherever possible, with historical information about their past extent. The atlas provides an accurate regional inventory of the areal extent of glacier ice on our planet during the 1970s as part of a growing international scientific effort to measure global environmental change on the Earth’s surface.
The chapter is divided into seven geographic parts and one topical part: Glaciers of the Former Soviet Union (F–1), Glaciers of China (F–2), Glaciers of Afghanistan (F–3), Glaciers of Pakistan (F–4), Glaciers of India (F–5), Glaciers of Nepal (F–6), Glaciers of Bhutan (F–7), and the Paleoenvironmental Record Preserved in Middle-Latitude, High-Mountain Glaciers (F–8). Each geographic section describes the glacier extent during the 1970s and 1980s, the benchmark time period (1972–1981) of this volume, but has been updated to include more recent information.
Glaciers of the Former Soviet Union are located in the Russian Arctic and various mountain ranges of Russia and the Republics of Georgia, Kyrgyzstan, Tajikistan, and Kazakstun. The Glacier Inventory of the USSR and the World Atlas of Ice and Snow Resources recorded a total of 28,881 glaciers covering an area of 78,938 square kilometers (km2).
China includes many of the mountain-glacier systems of the world including the Himalaya, Karakorum, Tien Shan and Altay mountain ranges. The glaciers are widely scattered and cover an area of about 59,425 km2. The mountain glaciers may be classified as maritime, subcontinental or extreme continental.
In Afghanistan, more than 3,000 small glaciers occur in the Hindu Kush and Pamir mountains. Most glaciers occur on north-facing slopes shaded by mountain peaks and on east and southeast slopes that are shaded by monsoon clouds. The glaciers provide vital water resources to the region and cover an area of about 2,700 km2.
Glaciers of northern Pakistan are some of the largest and longest mid-latitude glaciers on Earth. They are located in the Hindu Kush, Himalaya, and Karakoram mountains and cover an area of about 15,000 km2. Glaciers here are important for their role in providing water resources and their hazard potential.
The glaciers in India are located in the Himalaya and cover about 8,500 km2. The Himalaya contains one of the largest reservoirs of snow and ice outside the polar regions. The glaciers are a major source of fresh water and supply meltwater to all the rivers in northern India, thereby affecting the quality of life of millions of people.
In Nepal, the glaciers are located in the Himalaya as individual glaciers; the glacierized area covers about 5,324 km2. The region is the highest mountainous region on Earth and includes the Mt. Everest region.
Glaciers in the Bhutan Himalaya have a total area of about 1,317 km2. Many recent glacier studies are focused on glacier lakes that have the potential of generating dangerous glacier lake outburst floods.
Research on the glaciers of the middle-latitude, high-mountain glaciers of Asia has also focused on the information contained in the ice cores from the glaciers. This information helps in the reconstruction of paleoclimatic records, and the computer modeling of global climate change.