New Delhi: As many as 4,699 lakes in the Indian Himalayan region at an altitude above 3000-m above mean sea level have been found in an ISRO study revealing the wonders of Himalayas.
According to the first Atlas on High Altitude Lakes of the hills, the largest lake is Pangong Tso.
It is a long narrow lake spread over the Indian and Chinese territory in the upper drainage basin of the Indus river, at the east end of the Karakoram Range, says the study.
The study also cracks the belief that Tso Lhamo lake or Chho Lhamo or Cholamu lake --the source of river Teesta--is India`s highest lake, located at an altitude of 5,330 m in eastern Himalaya.
The new highest lakes altitudinal distribution shows that lakes are detected up to 6000m altitude. Most of these are very small and mapped as point feature.
Among the sizable lakes with at least 25 hectares area, the highest one is observed in western Himalaya at 5749 m in Jammu and Kashmir.
"A total of 4699 High Altitude lakes have been mapped. This includes 1996 small lakes (2.25 hecatres area). The total area of high altitude lakes is 126125 hectares," it says.
In eastern Himalaya, lakes above 5000-m are observed in the state of Sikkim.
A cluster of large lakes are nestled at the altitude of 5000 m in the north-eastern side of the Kanchanjangha range (Khangchengyao), next to the Tibetan plateau.
One of the lakes in this cluster is Cholamu lake.
It is a small lake formed by the melting of the Teesta Khaytse glacier. The reported depth of the lake is around 5.5 m.
The first survey of Cholamu lake lake was done by the British explorer Joseph Dalton Hooker, during 1847. His findings with the view of the lake as observed from the Donkiana pass was published in 1849.
The Indian Himalayas cover approximately 591,000 sq km or 18 per cent of India`s land surface and spread over six Himalayan states--Jammu and Kashmir, Himachal Pradesh, Uttarakhand, Sikkim, Arunachal Pradesh and some parts of West Bengal.
The ISRO exercise was undertaken under National Natural Resources Management System (NNRMS) Standing Committee on Bio-resources and Environment (SC-B) of the Ministry of Environment and Forests.
The atlas has been prepared using the 2006-08 remote sensing images from the Indian Remote Sensing Satellite RESOURCESAT (IRS P6) including pre and post monsoon to achieve high accuracy of identification of lakes.
The lakes are mapped at 1:50,000 scale for the entire Himalayan states, whereas 1:25,000 scale mapping has been done for the state of Sikkim and the digital elevation data has been used to generate the elevation information and give the distribution pattern of lakes in relation to elevation.