Dear Link, With little water, China faces oblivion as a liveable region on earth.
Australia can and should offer help. Whatever needed. Oh humanity! Chinese Scientists Are Trying to Shield Melting Glaciers From the Sun By Sharon Chen with Luz Ding, Bloomberg News Jul 6, 2023 (snip) https://www.bnnbloomberg.ca/chinese-scientists-are-trying-to-shield-melting-glaciers-from-the-sun-1.1942476 (Bloomberg, ) -- The air was thin as a group of scientists trudged through snow near the peak of the Dagu Glacier in southwestern China on a gloomy June morning. It was quiet up there, 3 miles above sea level, except for the sound of running water — a constant reminder of the ice melting right beneath their feet. As they trekked upwards, oxygen canisters tucked into their fleece jackets, porters walked alongside carrying thick rolls of white fabric. The researchers planned to spread those sheets across more than 4,300 square feet (400 square meters) of the mountain. The film was designed to reflect the sun’s rays back into the atmosphere, effectively shielding the glacier from the heat and hopefully preserving some of its ice. For decades, Dagu has supported the lives of tens of thousands of people who live around it. The glacier’s meltwater provides drinking water and helps to generate hydropower, while the majestic views of the Tibetan Plateau can attract more than 200,000 tourists a year, fueling an industry that keeps over 2,000 people employed .. The glacier has already lost more than 70% of its ice over the past half century .. This time, Zhu’s team was testing out a new material that their research suggests has the potential to reflect more than 93% of sunlight and help Dagu actively lose heat. The film is made out of cellulose acetate, a natural fiber made from plants, in order to minimize its environmental impact. The substance can also be used as small particles deposited by drones on less accessible glaciers. Previous studies have shown that covering parts of glaciers with special materials can reduce the melting of snow and ice by between 50% and 70% compared with unprotected surfaces. But chemicals or plastic particles from the sheets could negatively impact local ecosystems and downstream water quality, according to Matthias Huss, a professor of glaciology at ETH Zurich. Covering large glacial areas may also have huge and unexpected consequences. On the fourth day of the Dagu expedition, Zhu’s team finally managed to lay down the sun-reflecting sheets after the weather improved. They’ll return in September to remove the shields and take measurements to evaluate how well they worked. The researchers also collected water samples to examine the environmental impact. The experiment is set to continue for three to five years, after which the scientists will decide whether to try using their materials on other glaciers in China, or even take them abroad. It took tens of millions of years for the Tibetan Plateau to rise to its height today. The India and Asia tectonic plates collided, making the top cold enough to host the glaciers and snow that feed nearly all the major rivers in the region, including the Ganges, Mekong, and Yangtze. Together they are lifelines for billions of people across Asia. In comparison, the reverse is happening at warp speed — the plateau has lost over 15 % of its glaciers in just 50 years. Read More: Vanishing Ice on Highest Mountains Threatens Quarter of Humanity The vast majority of glaciers around the world are retreating rapidly, leading to rising sea levels and deadly floods. Covering parts of them with sunlight-reflecting blankets is like placing a band-aid on a gushing wound. Even if the world manages to keep global warming below 2C compared to pre-industrial times — the target most countries committed to when they signed the Paris Agreement in 2015 — less than half of the roughly 4,000 glaciers in the Alps today will remain by the end of the century. Huang Shihai, deputy head of the Dagu Glacier Management Bureau, has seen firsthand what climate change has brought to Heishui County, which sits at the bottom of the glacier. Since moving there in 2006, he’s watched as summers arrived earlier, winters got warmer, rivers grew dirtier and extreme weather events occurred more frequently. Living near the icy mountain, Huang never had much use for short-sleeved shirts. Now he starts wearing them as early in the year as May. He worries constantly that Dagu might disappear forever, and about the impact that will have on the people who rely on it. “There is a sense of crisis,” he said. --With assistance from Akshat Rathi. ©2023 Bloomberg L.P. _______________________________________________ Link mailing list [email protected] https://mailman.anu.edu.au/mailman/listinfo/link
