Himalayan glaciers could lose up to 75% of their ice by the year 2100. Scientists have warned that the nearly 2 billion people who live downstream of the rivers that originate in Asia’s Hindu Kush Himalayas are in danger from dangerous flooding and water shortages due to the glaciers melting at unprecedented rates.
Flash floods and avalanches, according to research released on Tuesday by the International Centre for Integrated Mountain Development (ICIMOD) in Kathmandu, would become more frequent if greenhouse gas emissions were not drastically cut.
According to the report, this will also have a negative effect on the 1.65 billion people who live downstream from the 12 rivers that originate in the mountains and the 240 million people who live in the Himalayas.
According to climate change, “the people living in these mountains who have contributed next to nothing to global warming are at high risk,” said Amina Maharjan, a migration specialist and one of the report’s authors.
She said, “Current adaptation efforts are wholly insufficient, and we are extremely concerned that without greater support, these communities will be unable to cope.”
The cryosphere, which consists of the parts of Earth covered in snow and ice, has been identified in multiple previous investigations as being particularly vulnerable to climate change.
Recent studies have shown that glaciers on Mount Everest have lost the equivalent of two millennia’s worth of ice in just 30 years.
For the first time, “we map out the linkages between cryosphere change and water, ecosystems, and society in this mountain region,” Maharjan added. Global warming has caused “unprecedented and largely irreversible” changes to the region’s glaciers, snow, and permafrost, according to the paper. This rate of change has accelerated by 65 percent since 2010.
It predicted that by 2100, glaciers in the region would have shrunk by 30–50% if temperatures had risen by 1.5 or 2 degrees Celsius over preindustrial levels.
However, the areas where glaciers are expected to melt the most vary. Glaciers in the Eastern Himalayas, which include India and Bhutan, will lose up to 75% of their ice at 3 degrees Celsius of warming, which is exactly what the world is roughly on course for under current climate policy. This rises to 80% at a temperature increase of 4 degrees Celsius.
“We’re losing the glaciers, and we’re losing them in 100 years,” said Philippus Wester, an environmental scientist and ICIMOD fellow and the report’s principal author.
Afghanistan, Bangladesh, Bhutan, China, India, Myanmar, Nepal, and Pakistan are all included in the 3,500 km (2,175 mi) long Hindu Kush Himalaya.
The effects of climate change on the Hindu Kush Himalaya have been difficult for scientists to measure. Unlike in the European Alps and the Rocky Mountains of North America, there is no extensive archive of field measurements to show whether glaciers are expanding or contracting in the region.
The United States declassified spy satellite photographs of the region’s glaciers from the 1970s in 2019, giving scientists a fresh point of reference.
Increased field research and brand-new satellite technology created over the previous five years have improved scientists’ understanding of the shifts in progress. The information in the report is current as of December 2022.
According to Wester, “there is a much higher level of confidence now in these findings” compared to an ICIMOD study of the region conducted in 2019.
As a result, “we have a better sense of what the loss will be through 2100 at different levels of global warming.” This new information has prompted significant worry for the local Hindu Kush Himalayan population.
The analysis concluded that the region’s 12 river basins, including the Ganges, the Indus, and the Mekong, will likely reach their maximum flow rates around the middle of the century, which will have an impact on the over 1.65 billion people who rely on these rivers for their water needs.
Although it may appear that we will have more water since glaciers are melting at a faster rate, Wester argued that this water would more often come in the form of floods than a steady flow.
According to the study, by the end of the century, the area could experience a dramatic increase in the number of glacial lake outburst floods. There are 200 glacier lakes in these mountains, and all of them are considered risky. However, as the water supply reaches its peak, it begins to decline.
“Once ice melts in these regions, it’s very difficult to put it back to its frozen form,” said Pam Pearson, director of the International Cryosphere Climate Initiative, who was not involved in the investigation.
It’s like a huge ship out in the water,” she continued. It’s tough to halt the ice once it gets flowing. It will take a long time for glaciers, especially the large glaciers in the Himalayas, to stabilize after they begin losing mass.
According to Pearson, the snow, permafrost, and ice on Earth are crucial to keeping global warming within the 1.5 degrees Celsius limit agreed to at the 2015 Paris climate conference. The cryosphere is undergoing permanent changes, but “I get the sense that most policymakers don’t take the goal seriously,” she added.
Communities in the Himalayas are already feeling the effects of climate change, sometimes quite strongly. This year, residents of the Indian mountain village of Joshimath were forced to evacuate within days after the town’s foundations began to collapse.
The regional governments are making preparations for the coming changes. China is making an effort to improve the country’s water infrastructure. Additionally, early warning systems for glacial lake outburst floods are being installed in Pakistan.