Climate change has led to increased temperatures, sea level rise, increased natural hazards, etc. Glaciers are the very sensitive to climate change and its affects can be seen in glaciated zones around the globe.
Himalaya has huge repositories of glaciers that are reportedly retreating leading to glacier thinning. This glacier thinning due to melting has resulted in the development of new glacial lakes and the magnification of existing ones due to the accumulation of meltwater behind loosely consolidated end moraine dams that had formed from debris left out by glaciers while retreating. These moraine dammed glacial lakes are potential source of catastrophic disaster as they are inherently unstable (ICMOD, 2011; UNDP, 2013).
Fast melting of glacier or an extreme weather event such as heavy rainfall can easily trigger these glacial lakes to burst and can cause damage to vulnerable people and property living downstream in the valleys.
The flash flood due to sudden burst of a glacial lake produce the violent flow of water and associated debris and is known as a Glacial Lake Outburst Flood (GLOF). Lake Outburst and debris flow disaster in Kedarnath, Uttarakhand in June 2013 was one the destructive disaster occurred in Himalaya and still various potential disastrous lakes exists and are developing in this region (Allen et al, 2015).
Glaciers work as a water tower, sustaining the lives of millions downstream. The volumes of these glaciers vary – remaining sensitive to global temperature conditions. The glaciers have embedded within it many lakes which follow a seasonal pattern of freeze and thaw. With continuing warming trends, many glaciers are melting rapidly, giving birth to a large number of glacial lakes. These ‘moraine dammed’ lakes are comparatively feeble and its unexpected outburst is a threat to life, asset and infrastructure, downstream.
Glacial lake outburst floods (GLOFs) are related to global warming. As the temperatures in the Himalaya soar, the glaciers retreat during the summer, leaving behind water filled, moraine dammed, precarious lakes holding huge amounts of water in a very unstable geomorphology.
GLOFs have been known to occur in different parts of the world. In 1941, an outburst flood destroyed the city of Huaraz in Peru killing 4,500 people. Outbursts from a glacier-dammed lake in the Swiss Alps in 1968 and 1970 triggered debris flow and caused heavy damage to the village of Saas Balen.
In the Himalayan realms, with its greatest concentration of glaciers outside of the poles, such an event would assume catastrophic proportions with urban inroads in higher altitudes, ever-expanding infrastructure and poor to non-existent integrated water management systems as opined in a paper by P Mukhopadhyay, 2011, titled ‘GLOF- A Threat Present and Real: Indian Summary’.
According to the IPCC, 2001 assessments, the rising global mean temperatures by 2100 from 1.4° to 5.8°C, depending on the climate model and greenhouse gases emission scenario, would mean that up to a quarter of the global mountain glacier mass can disappear by 2050 and up to half could be lost by 2100 (IPCC, 1996). GLOF threats to the Indian Subcontinent: The Himalaya, ‘third pole’ of the earth, comprises one of the largest collections of glaciers and the threat is real.
Glacial lake monitoring and preparedness for disaster risk reduction are the prime most need of these fragile regions now. Glacial lake are needed to be mapped and monitored to recognize the GLOF risks associated with them. Indian Space Research Organisation (ISRO) among many other organisations working in the area, has also taken the responsibility and has been engaged in glacial lake monitoring and water bodies in the Himalayan region of Indian River Basins.
ISRO has increased its capabilities to show the potential of satellite remote sensing to monitor the glacial lake and water bodies. High resolution data such as Cartosat-2 Panchromatic, Resourcesat – 2 LISS VI multispectral and RISAT-1 SAR Radar images was used to monitor regularly two lakes – Lhonak lake and Pareechu lake during 2013 to 2015.
Also, glacial lake monitoring and water bodies with water spread area more than 50 hectare for on monthly basis for June to October for 5 years (2011-2015) has been performed.
Inventory of glacial lake and water bodies with water spread area more than 10 hectare has been prepared. According to inventory there are total of 2026 glacial lakes and water bodies in Indian River basin of Himalaya out of which 503 are glacial lakes. It has been found that about 1600 glacial lakes and water bodies have water spread area between 10 and 50 hectare and about 200 water bodies have between 50 and 100 hectare.
Relation between elevation and water spread area
A comparison with elevation has revealed that more than 50 per cent i.e. about 1167 glacial lakes and water bodies are located within the elevation range of 4000 to 5000m. A basin wise inventory showed that Brahmaputra basin has most number of glacial lakes and water bodies i.e. 1391 followed by Indus (351) and Ganga basin (284). Brahmaputra Basin has 295 glacial lakes and 1096 water bodies whereas Ganga basin has 179 Glacial lakes and 105 water bodies. Least number of glacial lakes lies in the Indus basin.
ISRO has done remarkable work by inventorying the glacial lake monitoring and water bodies. They are also regularly monitoring and providing information on inventory and monthly changes through their Bhuvan and India-WRIS portal. All this together is very useful for identification of potentially dangerous lakes prone to GLOF and giving early warning to mitigate disasters. This monitoring is also helping in prioritizing of glacial lake monitoring for GLOF studies and climate change studies.
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Steve Ovett, the famous British middle-distance athlete, won the 800-metres gold medal at the Moscow Olympics of 1980. Just a few days later, he was about to win a 5,000-metres race at London’s Crystal Palace. Known for his burst of acceleration on the home stretch, he had supreme confidence in his ability to out-sprint rivals. With the final 100 metres remaining,
[wptelegram-join-channel link=”https://t.me/s/upsctree” text=”Join @upsctree on Telegram”]Ovett waved to the crowd and raised a hand in triumph. But he had celebrated a bit too early. At the finishing line, Ireland’s John Treacy edged past Ovett. For those few moments, Ovett had lost his sense of reality and ignored the possibility of a negative event.
This analogy works well for the India story and our policy failures , including during the ongoing covid pandemic. While we have never been as well prepared or had significant successes in terms of growth stability as Ovett did in his illustrious running career, we tend to celebrate too early. Indeed, we have done so many times before.
It is as if we’re convinced that India is destined for greater heights, come what may, and so we never run through the finish line. Do we and our policymakers suffer from a collective optimism bias, which, as the Nobel Prize winner Daniel Kahneman once wrote, “may well be the most significant of the cognitive biases”? The optimism bias arises from mistaken beliefs which form expectations that are better than the reality. It makes us underestimate chances of a negative outcome and ignore warnings repeatedly.
The Indian economy had a dream run for five years from 2003-04 to 2007-08, with an average annual growth rate of around 9%. Many believed that India was on its way to clocking consistent double-digit growth and comparisons with China were rife. It was conveniently overlooked that this output expansion had come mainly came from a few sectors: automobiles, telecom and business services.
Indians were made to believe that we could sprint without high-quality education, healthcare, infrastructure or banking sectors, which form the backbone of any stable economy. The plan was to build them as we went along, but then in the euphoria of short-term success, it got lost.
India’s exports of goods grew from $20 billion in 1990-91 to over $310 billion in 2019-20. Looking at these absolute figures it would seem as if India has arrived on the world stage. However, India’s share of global trade has moved up only marginally. Even now, the country accounts for less than 2% of the world’s goods exports.
More importantly, hidden behind this performance was the role played by one sector that should have never made it to India’s list of exports—refined petroleum. The share of refined petroleum exports in India’s goods exports increased from 1.4% in 1996-97 to over 18% in 2011-12.
An import-intensive sector with low labour intensity, exports of refined petroleum zoomed because of the then policy regime of a retail price ceiling on petroleum products in the domestic market. While we have done well in the export of services, our share is still less than 4% of world exports.
India seemed to emerge from the 2008 global financial crisis relatively unscathed. But, a temporary demand push had played a role in the revival—the incomes of many households, both rural and urban, had shot up. Fiscal stimulus to the rural economy and implementation of the Sixth Pay Commission scales had led to the salaries of around 20% of organized-sector employees jumping up. We celebrated, but once again, neither did we resolve the crisis brewing elsewhere in India’s banking sector, nor did we improve our capacity for healthcare or quality education.
Employment saw little economy-wide growth in our boom years. Manufacturing jobs, if anything, shrank. But we continued to celebrate. Youth flocked to low-productivity service-sector jobs, such as those in hotels and restaurants, security and other services. The dependence on such jobs on one hand and high-skilled services on the other was bound to make Indian society more unequal.
And then, there is agriculture, an elephant in the room. If and when farm-sector reforms get implemented, celebrations would once again be premature. The vast majority of India’s farmers have small plots of land, and though these farms are at least as productive as larger ones, net absolute incomes from small plots can only be meagre.
A further rise in farm productivity and consequent increase in supply, if not matched by a demand rise, especially with access to export markets, would result in downward pressure on market prices for farm produce and a further decline in the net incomes of small farmers.
We should learn from what John Treacy did right. He didn’t give up, and pushed for the finish line like it was his only chance at winning. Treacy had years of long-distance practice. The same goes for our economy. A long grind is required to build up its base before we can win and celebrate. And Ovett did not blame anyone for his loss. We play the blame game. Everyone else, right from China and the US to ‘greedy corporates’, seems to be responsible for our failures.
We have lowered absolute poverty levels and had technology-based successes like Aadhaar and digital access to public services. But there are no short cuts to good quality and adequate healthcare and education services. We must remain optimistic but stay firmly away from the optimism bias.
In the end, it is not about how we start, but how we finish. The disastrous second wave of covid and our inability to manage it is a ghastly reminder of this fact.