According to a new study, reported by BBC, the glaciers in the tropical Andes have shrunk by 30-50% since the 1970s. These glaciers are crucial, as they provide fresh water in South America for tens of millions of people.
The study, published in the academic journal The Cryosphere, blamed the melting glaciers on the temperature rise—specifically, the rise of 0.7C from 1950 to 1994. As a result, glaciers at lower altitudes (below 5,400 mm) have lost roughly 1.35 m in ice thickness annually after the late 1970s.
“Because the maximum thickness of these small, low-altitude glaciers rarely exceeds 40 metres, with such an annual loss they will probably completely disappear within the coming decades,” said lead author Antoine Rabatel, from the Laboratory for Glaciology and Environmental Geophysics in Grenoble, France, to BBC.
BBC shares more about the problems of the melting glaciers in the Andes:
Without changes in rainfall, the region could face water shortages in the future, the scientists say.
The Santa River valley in Peru could be most affected; its hundreds of thousands of inhabitants rely heavily on glacier water for agriculture, domestic consumption, and hydropower.
Large cities, such as La Paz in Bolivia, could also face problems. “Glaciers provide about 15% of the La Paz water supply throughout the year, increasing to about 27% during the dry season,” said co-author Alvaro Soruco from the Institute of Geological and Environmental Investigations in Bolivia.
This news come just two months after we shared that the melting rates of glaciers in Antarctica are accelerating due to global warming, according to a new study by a Texas A&M University researcher. Alejandro Orsi, associate professor of oceanography, and his colleagues from the University of Gothenburg in Sweden, “examined the entry to one of three cross-shelf passages in the Amundsen Sea that allow warm oceanic water to reach beneath the ice shelves in front of the Thwaites and Pine Island Glaciers, which show the fastest thinning.” Their findings were far from ideal: They found a year-long persistent inflow of warm bottom water along this trough.
What’s more, Austrian scientists at the University of Innsbruck have also found that the single greatest cause of rising sea levels over the past century are melting glaciers. The scientists disclose that between 1902 and 2007, the total sea level rise was 20 centimeters (about 8 inches) and of that, glaciers melting contributed 11 centimeters (4.33 inches). They estimate that by the year 2100, melting glaciers could potentially raise sea levels by an additional 22 centimeters.
Unfortunately, melting glaciers are becoming a devastating norm: Due to global warming, many of the world’s glaciers are rapidly melting at unprecedented rates and are breaking off unnaturally. In July, NASA satellites confirmed that an iceberg more than double the size of Manhattan, measuring 59-square-mile (150 square kilometers), has broken off the Petermann Glacier in Greenland, and global warming was the culprit.
This news was followed by a study (published in Nature Climate Change) by Yao Tandong, a glaciologist at the Chinese Academy of Sciences’ Institute of Tibetan Research in Beijing, and his colleagues, disclosing that the glaciers on the Tibetan plateau and the surrounding areas in the Himalaya are in rapid retreat.
And then, of course, is the news that, according to new research published in the journal Geophysical Research Letters, the Patagonian Icefield of South America have been on the decline for the past four decades, with the rate of melting increasing by half over the past decade. Since 1998, the melting of the southern and northern Patagonian ice fields–which are the largest mass of ice in the southern hemisphere outside of Antarctica–have contributed about 2 percent of the total observed sea level rise.
Wondering what the cause of melting glaciers is? Consider this: According to a new study, led by climate scientist Jonny Day at the National Centre for Atmospheric Science at the University of Reading, the loss of arctic sea ice is, at the very least, 70 percent man-made. And that’s just the low ball estimate–the study shares that climate change could be up to 95 percent due to human-induced climate change!
Photo by Carlos Varela