While the investigation is ongoing to ascertain the cause of flash flood in Uttarakhand's Chamoli district, it is being suspected that either an avalanche or a glacier lake outburst flood (GLOF) was responsible for it. So far, 31 deaths have been reported due to the natural calamity which took place on Sunday, and media reports claim that 170 people are still missing.
Dr Roxy Mathew Koll, a climate scientist at the Indian Institute of Tropical Meteorology in Pune, told News18, "It is quite possible that climate change and melting of fresh snow led to piling up of water in the Uttarakhand area and caused the flash floods. The recent climate change assessment report for India shows that the Himalayas temperatures are warming due to climate change, at a rate of 0.2°C per decade. At high elevations (above 4000 m), the warming rate is up to 0.4°C per decade. This warming has led to a significant melting and decline in glacier mass over the Himalayan region in recent decades."
Despite the rapid modification in glacial mass due to climate change and dangerous glacial lake formations, the monitoring of Himalayan glaciers is still at a very nascent stage in India.
A brief review of the Mass Balance Status of Indian Himalayan Glaciers (published in 2018) states that according to the Geological Survey of India there are a total 9,575 glaciers in the Indian Himalayan Region (Sangewar and Shukla, 2009), out of which only 15 glaciers have been studied for glacier mass balance till now.
Apart from that, glaciologists pointed out that to be better prepared for the kind of calamity that happened in Uttarakhand recently, what we need to do urgently is to start mapping the hazard and vulnerable areas where the possibilities of GLOF and landslides are higher, monitor the changes of glacial lakes, incorporate effective warning systems, which can mitigate the loss of lives that we have seen in Uttarakhand this week, and most importantly, invest in glacial research.
Hazard and vulnerability mapping
Koll further pointed out, "Many times, climate change-induced events are accelerated due to land-use changes. Land-use changes, mostly caused by human-made construction and infrastructural development, can loosen up glacier mountains and slopes that are already exposed to climate change."
Dr Shresth Tayal, a glaciologist at the Centre for Himalayan Ecology at TERI, told News18 that such natural calamities could not be controlled. Still, we can better adapt our communities, our constructions, and our resources if we have a definitive hazard and vulnerability mapping of India.
"The possibility is that we can identify individual river valleys and categorise them in terms of their vulnerability to such flash floods. We have done a very similar thing with earthquakes. We have the seismic map for the entire country, and India has been classified into different zones. Therefore, we know that the cities and towns in zone 5 are more vulnerable and prone to earthquakes. Likewise, if a similar mapping of Himalayan glaciers can be done, and vulnerability zones can be identified, we would be better equipped to face such calamities," said Tayal.
Tayal pointed out that once we know the vulnerable zones, we would be able to decide what kind of construction would affect the local terrains adversely and learn more about potential risk zones/areas and take action on such zones on a priority basis to avert Uttarakhand like tragedies.
According to NDMA guidelines, "for GLOFs the starting point for any assessment is establishing a comprehensive and up-to-date lake inventory for the region of interest, including existing information from studies that have assessed hazard and/or risk associated with the mapped lakes."
Identifying potentially Critical Lakes
The guidelines were issued by NDMA last year and aimed to accelerate administrative response and amalgamate the nation's relevant scientific capabilities to mitigate the losses caused by glacier lake outburst floods and landslides.
The guidelines prescribe an immediate need to monitor dangerous lakes such as 'rapidly expanding glacial lakes that result from continuous heavy rainfall, the formation of new glacial lakes resulting from blockages in the glacial hydrological system or associated with surging glaciers, and newly formed landslide lakes.'
Such dangerous lakes are generally identified by field observations, historical records, geomorphologic and geotechnical characteristics of the lake/dam and surroundings.
While glacial lakes expand during monsoon, it also becomes harder to examine the expansion due to cloud cover and optical remote sensing does not work effectively during this time. Therefore, the NDMA guidelines suggest that during such time Synthetic-Aperture Radar (SAR) imagery should be used to automatically detect changes in water bodies, including new lake formations.
The guideline further stated, "Methods and protocols could be developed to allow year-round remote monitoring of lake bodies from space, as a compliment and the precursor to ground-based early warning systems at critical lakes, which are unpredictable. Thus, more time is available to plan and implement measures to reduce the likelihood of GLOF."
Funding the Study of Glaciers, Creating Jobs
Another problem in establishing monitoring systems is that not many Indians are studying glaciers, even though India is nestled in the Himalayas' lap, which has thousands of glaciers. "It is indeed ironical that despite so many glaciers in our country, only a handful of people study glaciology here," said Tayal.
"Since there are a minimal number of jobs available for students after they complete their education in glaciology, they often take up other branches of study which offer more lucrative jobs. Therefore, the first order of business should be to build the human resource by creating more jobs for future students," pointed out Tayal.
Tayal added that what would also help is scaling-up research and development for glacier studies with funding and support from the government and the Science and Technology department. It is vital to establish new educational institutions where glaciology can be studied and empower the existing universities and colleges where the subject is already being taught.
Dr Santosh Kumar Rai, Senior Scientist and the head of the Department of Glaciology and Hydrology at Wadia Institute of Himalayan Geology stated that what India needs is an effective early warning system to ensure that quick actions can be taken during such natural calamities.
"European and American countries have such early warning systems for GLOFs, and a few of them have also been established in Nepal. However, in India, it is logistically, and infrastructure wise a challenging task to establish them since most of the Himalayan glaciers and glacial lakes is at great heights," said Rai.
Rai pointed out that no roads lead up to the glaciers, and glacial lakes in the Himalayan regions, unlike the West where they already have established road connectivity. Therefore, it becomes challenging to navigate such rough terrains and set up a warning system.
However, Rai said that such early warning systems are essential. They forecast probable events; issue alerts before any such event occurs, and help in prompt activation of emergency response.