Itanagar: Posing serious threats to the survival of ecosystem in Arunachal Pradesh and having deeper socio-economic impacts, large parts of the eastern Himalayas may become devoid of snow if temperature continues to rise due to climate change, experts say.
"In the event of an increase in temperature by 0.5 degree Celsius about 912 sq km of mountain slopes will be devoid of snow cover and in the event of 1 degree C increase further 860 sq km slope facets will lose snow cover," geologist S K Patnaik of Arunachal's Rajiv Gandhi University told PTI.
The total area under snow in Arunachal Pradesh was estimated to be around 7236 sq km few years ago.
According to the State Action Plan on Climate Change, maximum temperature is projected to increase by 2.2 to 2.8 degree Celsius during 2030s and towards 2080s the increase is projected by 3.4 to 5 degree C.
Similarly, minimum temperature is projected to increase by 1 to 2.6 degree C during 2030s and by 2.8 to 5 degree C during 2080s.
An analysis of IMD data in Tawang district estimates that the temperature has risen by 1.4 degree Celsius in the last 100 years.
"Warmer periods are setting in faster as the winter is becoming narrower. Areas above 4000 m elevation are progressively experiencing greater warning," said Dr Prasanna K Samal, scientist In-charge at the GB Pant Institute of Himalayan Environment and Development.
As one of the world's 18 biodiversity hotspots, Arunachal is home to many endemic, endangered and threatened species of flora and fauna, as well as to the indigenous people, who are primarily dependent on its biological resources.
Dr Sanjeeb Bharali of forestry department in the North Eastern Regional Institute of Science and Technology (NERIST) warned that climate change will not only threaten the biodiversity, but also affect the socio-economic condition of the people as about 62 per cent of the total working population is engaged in agriculture.
"If we go by what the people are saying then there has been a shift in agriculture calendar as a result. Productivity has been affected while new pests are being reported," he said.
Changes in temperature can also result in increase in vector-born diseases like Kalajar, Malaria, dengue, etc, he warned.
Climate of this north-eastern state is influenced greatly by the Himalayan mountains and large variations in altitude across the state.
As a result of a permutation and combination of various climatic factors like temperature, rainfall and slope angle, the spread of snow and ice on the peaks of Arunachal Himalayas has already started changing.
Kesang Goiba, village headman (Gaon Bura) of the remote Mechuka valley in West Siang district, recalls that a couple of decades ago snowfall was very regular and went upto 2-3 feet in height.
"Now it is hardly a few inches of snowfall and that too irregular," he said. Locals in the state capital say that even the upper regions of Itanagar used to experience snowfall few decades ago.
The Himalayas has the world's second largest coverage of glaciers and permanent snowfields after the polar region.
Scientists say that since snow and glacier melt water are important source of many rivers originating in the Himalayas, monitoring the snow-cover changes is essential to assess the future hydrologic cycle.