Uttarakhand Tragedy | Climate change and its imperatives for energy security

The floodwater, mud and boulders roared down the mountain along the Alaknanda and Dhauliganga rivers, breaking dams, sweeping away bridges and forcing the evacuation of many villages while turning the countryside into what looked like an ash-colored moonscape. (Image: AP)

On February 7, Uttarakhand faced a flash flood impacting the life and infrastructure of the state. The immediate cause for the flooding is considered to be the breakage of a glacier or a glacier lake bursting in the upper catchment of the Himalayas.

A scientific investigation will be required to understand the cause of such an event; however, the role of global warming-induced climate change and environmental degradation is the major precursor in occurrence as well as increase in frequency of such events.

The rate of warming of the Himalayan region is reported to be higher than the global average and the temperature is projected to increase further in the range of 1-3°C by mid-century. The Indian Meteorological Department (IMD), based on data from 1951 to 2010, has reported an increase in warming over the central and eastern parts of the Himalayas.

Almost 7.7 percent of global glacierised area is present in South Asia supporting close to 10 percent of the global population by providing water during the lean season through snow and ice melt. According to the Geological Survey of India, there are 9,575 glaciers in the Indian Himalayas distributed among the three river basins — Indus, Ganga and Brahmaputra. However, more than 90 percent of Indian glaciers are small to very small in size — being smaller than 5 km in length and smaller than 5 sqkm in area. Most of them are smaller than 1 sq km. Only a few glaciers such as Siachen, Gangotri and Zemu are bigger than 10 sq km.

The Intergovernmental Panel on Climate Change (IPCC), in its 2014 report, mentioned that while smaller glaciers are more vulnerable to impacts of climate change and are bound to disappear, larger glaciers will continue to hold ice but will be shrinking for the next few decades even if the temperature stabilises in the near future. The Himalayan glaciers are also vulnerable due to their geographical setting. These glaciers are located close to the tropics at low latitudes, on the southern facing slopes of the Himalayas and so there is a natural build-up of high heat content in this region.

Thus, the occurrences of flash floods are bound to increase in the near future because of the rise in temperature over the Himalayas, the higher sensitivity of smaller glaciers, and other geographical factors.

These flash floods had catastrophic effects on the hydropower dams being constructed in the region and have fuelled the debate about the construction of such projects in the Himalayas. While 81 percent of the total hydropower potential in India is existing in the rivers flowing from Himalayan glaciers, only 29 percent of this potential has either been developed or is under construction. Once developed to its full potential, an additional 80,000 MW will be available to the country.

Considering the significance of hydropower projects for the local economy, as well as the country’s energy security, a decision for stopping the development of dams in the region may not be easy. Also, tourism is the backbone of economy in the Himalayan states, and the influx of tourists as well as the construction of related infrastructure may not be stopped. Hence, it is necessary to find alternative pathways which may ensure sustainable development, along with the ecological balance of the region.

The Way Forward

Lakes associated with the melting and retreat of glaciers has been considered to be possessing significant hazard potential, owing to the sudden breach of natural embankments of these lakes. The flood potential of these lakes could have significant impact on the infrastructure downstream.

It is necessary to develop a vulnerability map of the Himalayas, similar to the seismic zonation map of the country, and categorise different river valleys based on the degree of vulnerability to such disasters. Subsequently, zone-specific strategies need to be adopted for better adaptation of communities, as well as infrastructure. The cost required for such a study would be much less than the expenditure incurred in relief and rehabilitation expenditure incurred subsequent to such a tragedy.

Further, an environmental impact assessment (EIA) is a pre-requisite for the clearance of hydro-power projects from the government. But, the EIA conducted by the hydropower companies are mainly focussed on the likely impacts due to the installation of the dam on the downstream communities. These projects should also make a comprehensive assessment of the impacts due to climate and vulnerability to glaciers upstream. This is important for the projects located in the Himalayas.

Natural calamities cannot be controlled, but we can better adapt our communities, our constructions, and our resources balancing the economic growth with environmental conservation.