Important Antarctic glaciers may collapse earlier than expected

Important Antarctic glaciers may collapse earlier than expected

Scientists speak at the meeting American Geophysical Union The fall conference in New Orleans this month, Report A key part of Thwaites Glacier, the cornerstone of the Antarctic glacier, may collapse in the next five to ten years. The study, led by Erin Pettit of Oregon State University, predicts that the Thwaites ice shelf will burst within the next ten years due to an astonishing increase in surface cracks and cracks. So far, the floating part at the estuary of Thwaites Glacier, called the ice shelf, has been relatively stable, but scientists have stated that it may be “broken like a car windshield.”

Thwaites Glacier It is one of the largest glaciers in Antarctica, about the size of the United Kingdom or Florida. The meltwater in Thwaites alone has caused 4% of the global sea level rise, which has led to it being widely concerned by the scientific community in recent years.Researchers have observed dramatic changes in glaciers, including Double the speed In the past three years, scientists have warned that the worst has yet to come.

A crack spanning almost the entire ice shelf for more than 40 kilometers is the most relevant sign of impending collapse. In the eastern ice shelf of Thwaites, there are no obvious cracks on the surface, but the radar technology used to penetrate the ground revealed the thin ice area marked by cracks at the bottom of the glacier, which severely weakened this part of the ice shelf. The cracks are likely to extend to meet the thinner area of ​​the ice, which will cause the cracks to split further in a “zigzag” pattern, as the scientists have drawn, eventually leading to the complete rupture of the ice shelf.

At present, the flow velocity of the eastern section of the Thwaites Ice Shelf is about one-third that of the western section, because its ice is fixed in place by contact with the subsea mountain range (called “pinning points”), which limits The flow of the ice shelf. This area. However, new data from GPS stations located on the ice shelf indicate that the ice is beginning to move around the mountain, which will cause it to crack and decompose faster.The Eastern Ice Shelf of Thwize is Loss of control over a fixed point, Has a great impact on the ice directly behind it.

Thwaites was given the nickname “Apocalyptic Glacier in Antarctica” because if the ice shelf collapses, the glacier and the large amount of ice flowing upstream of the glacier will no longer be restricted and cannot accelerate into the ocean. Anne Le Broq, a senior lecturer in physical geography at the University of Exeter, explained: “What we need to consider is the potential long-term impact on other grounded ice sheets.” If the entire glacier melts, the global sea level will rise by 65 cm, or about two. foot. If Thwaites Glacier and other important neighboring glaciers such as Songdo Glacier cannot stop the West Antarctic Ice Sheet at sea level equivalent to 3.3 meters (10.8 feet), then it may affect coastlines around the world.

The collapse of Thwaites Glacier. Image Credit: NASA/James Yungel

Climate scientists said: “Despite the distance, the polar regions and their changes have and will control the climate on the earth and thus our own society.” Marco Tedesco Researchers at the Lamont-Doherty Earth Observatory and Columbia University’s School of Climatology. “The collapse of Thwaites will catalyze rising sea levels, thereby accelerating the destruction of our society from climate change,” he added.

Tedesco further explained that the melting of glaciers and their ice shelves is worrying because it will add fresh water to the Southern Ocean, which will have a “strong impact on ocean currents and ocean circulation.” In the northern hemisphere, “increased melting of the Greenland ice sheet may disrupt ocean circulation, thereby bringing warmer weather to Western Europe and the eastern United States,” Le Brock said. “The global impact of these changes in the polar regions has brought them to the forefront of climate change science.”

The research involves a combination of satellite data, ground penetrating radar measurements, and GPS measurements. Satellite technology can capture the acceleration of ice in the area along the fault zone.Many of these observations are Incorporate computer model Scientists are using it to further understand and predict the current and future behavior of ice shelves.

What makes Thwaites Glacier the center of attention is International Thwaites Glacier Cooperation (ITGC), a five-year intensive learning program for American and British researchers. Its US$50 million funding was jointly awarded by the National Science Foundation of the United States and the British Natural Environment Research Council. Every summer in Antarctica, a team of scientists travels to the south to collect data from the air, sea, and land in order to carefully examine the thoughts.This year’s team currently In isolation Before the last stop of their journey to Antarctica, in Patagonia. Since there are several research seasons left in the ITGC plan, the disintegration of the ice shelf will be continuously monitored and reported to world leaders.

The screenshot of the virtual press conference shows International Thwaites Glacier Cooperation The disintegration of the ice shelf will continue to be monitored.

What worries scientists is not only the breaking and breaking of ice, but also the increase in ocean temperature, which is melting the ice shelf from below. Much of the western Antarctic ice sheet is below sea level, which means that as the glaciers retreat inland, more ice is exposed to warm water. This transition caused great concern, because melting from below also loosened Thwaite’s control of its fixed point, causing the glacier to become more unstable. a stressful job By drilling hundreds of meters deep in the ice and deploying Diving robot Dive under the ice shelf and collect data autonomously.

The disappearance of these major ice sheets, especially when combined with the increase in the melting of the Greenland ice sheet, has the potential to change the climate as we know it, “changing our society much faster than we thought,” Tedesco warned . Based on his research on economic and climate impacts, Tedesco said, “The combination of accelerated sea level rise and floods, extreme events and precipitation has caused losses to the most vulnerable people in society and financial assets or related properties.”

The findings released this week are yet another catastrophic blow to the fate of this vital Antarctic glacier. Since the Antarctic research season has just begun, the changes reported by Thwaites Glacier in the coming months will be shocking.