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Antarctic Glaciers Are Melting at an Alarming Rate, Threatening Coastal Cities and Human Survival

The amount of ice-covered Antarctic ocean has fallen to an all-time low, scientists report, adding that the thicker ice shelves that support Antarctica’s ground ice sheet have been exposed to waves and higher temperatures. At the same time, the US National Snow and Ice Data Center (NSIDC) also stated that during the period from February 13 to 19 this year, Antarctica’s sea ice area fell to 1.91 million square kilometers, the lowest level since records began in 1979. If global temperatures continue to rise and the glaciers near Antarctica melt, it will lead to catastrophic sea level rise in the next few centuries… Faced with such difficulties, what is the future of the earth?

Will the coastal cities be submerged? How far is the disaster from us?
As early as May 12, 2014, in a news article, US researchers warned that the ice sheet on the west side of Antarctica had begun to collapse, and the process was “unstoppable”. The Thwaites Glacier, the “building block” holding the West Antarctic Ice Sheet together, has begun to collapse, and in the long run, the West Antarctic Ice Sheet may disappear over time, the team of scientists reported. The meltwater is enough to raise sea levels by more than 3 meters. Affected by this, many low-lying coastal cities around the world may be submerged by seawater in the future.

This is not alarmist talk. In the same year, a paper published in the US journal Science stated that in just 200 years, the outermost edge of Thwaites Glacier will continue to retreat, retreating to a ridge under the water, which is also slowly melting step back. Using model data, the researchers concluded that once the glacier’s “grounding line,” the point at which the ice begins to float, retreats and crosses the ridge, the glacier will quickly fall into avalanche. what does that mean? From radar mapping of Antarctica’s West Antarctic glacier, described by another research team in Geophysical Research Letters, we know that this 600-meter-deep ridge is the last barrier for bedrock beneath the glacier to dip into the basin below. In short, the collapse of this glacier would flood West Antarctica with seawater and cause the region to lose all its glaciers.

For human beings, the melting of glaciers will constitute a huge disaster.

In November 2021, a satellite image showed that the ice shelf supporting Thwaites Glacier had developed several large cracks across the ice wedge. Large cracks in an ice shelf are like cracks in a windshield, requiring only a little force to create what looks like a spider web of cracks. Once the ice shelf breaks up, most of the glaciers that are now bound by the ice shelf will melt more than three times faster. If this trend is allowed to develop, the worst-case scenario is that the disappearance of Thwaites Glacier may attract surrounding glaciers, and then trigger a wider collapse of the West Antarctic ice sheet.

Scientists make a valiant attempt to enter Thwaites Glacier with an unmanned submarine, but it returns with chilling news: The glacier is melting faster than anyone thought. Before this, climate scientists had paid attention to Thwaites Glacier for more than two decades. When they sent unmanned submarines to the depths below Thwaites Glacier, they did not know how fast the glacier was melting, nor did they know how the glacier was melting. When will it collapse. The attempt made people even more disturbed: A previously underestimated current of warm water flowing in from the east is slowly melting several important “fixation points” that hold the glacier to the land, a situation that may cause the glacier to slip and retreat. In other words, entire glaciers could break off land and drift out to sea.

Thwaites Glacier has always been known as the “Doomsday Glacier”, it is one of the fastest melting glaciers in Antarctica. Statistics show that since the 1980s, the Thwaites Glacier has lost about 595 billion tons of ice, and the melted water accounts for 4% of the global sea level rise. There is a vivid metaphor that the Thwaites Glacier is like a cork on a wine bottle. Once it collapses, the rest of the West Antarctic ice sheet will pour out.

In 2023, scientists will continue to conduct in-depth research. Satellite data show that in the past 40 years, the Antarctic sea ice area has changed greatly, and it has shown a trend of getting smaller and smaller in recent years. Researchers believe that its changes are caused by many complicated reasons, which cannot be simply It comes down to global warming.

Ice Shelf Collapse Brings Butterfly Effect Larsen B and Conger Enlightenment
For a long time, Antarctica has been known as the “stabilizer” of the global climate. One reason is that the high albedo of Antarctica’s sea ice reflects a large amount of solar radiation, which keeps the global temperature stable; the other reason is that the huge ice body in Antarctica has the function of absorbing heat and storing heat. , which can stabilize the global atmospheric energy balance. However, since 2016, the rapid changes in Antarctica’s glaciers, such as frequent extreme weather and rare heat waves, have increased the rate of melting of glaciers, and the chain reaction has begun to appear…

On April 20, 2022, the British “Independent” reported that scientists discovered that the Antarctic sea ice area has shrunk to a record low level. The main reason affecting it is the natural climate cycle, but more importantly, the climate warming caused by human factors question. The report mentioned that extreme climates in Antarctica have occurred frequently in recent years. The sea ice area began to shrink in 2014 and hit the lowest level in 2017. By 2020, Antarctica has encountered a rare heat wave. Compared with previous years, the highest temperature Rise of about 9.2 degrees Celsius.

The change in temperature directly leads to the reduction of sea ice area. This is a very serious phenomenon because it will accelerate the rate of global warming. Scientists have also given a clear explanation of the principle: “White sea ice can reflect the sun’s heat, but if the sea ice is replaced by dark sea water, the reflected heat will be less and the absorbed heat will be more. More.” This would lead to more sea ice melting and more seawater, which would absorb more heat, creating a vicious cycle.

Unfortunately, this is already happening in Antarctica. In 2002, the Larsen B ice shelf in the northern part of the Antarctic Peninsula collapsed, covering an area of ​​about 3,250 square kilometers. This was the largest ice shelf collapse in history. On March 15, 2022, another huge ice shelf “Conger” completely collapsed. It is located in eastern Antarctica and its area is equivalent to the combined area of ​​Huangpu District and Baiyun District of Guangzhou City.

NASA Earth scientist Catherine Corello-Walker said the collapse of the Conger Ice Shelf was one of the most significant events in Antarctica since the collapse of the Larsen B ice shelf in 2002. Unlike the Larsen B ice shelf in West Antarctica, the Conger Ice Shelf is located in East Antarctica, where the temperature is colder and more stable than in the west. It was once considered to be the region with the highest mid-latitude, the driest climate, and the lowest temperature on the continent. Before this, scientists did not expect an ice shelf collapse event to occur here.

In other words, the temperature change has rippled through colder parts of Antarctica, and scientists believe the collapse of the Conger Ice Shelf may have coincided with the extreme heat wave. Parts of Antarctica were nearly 40C hotter than the monthly average when the heatwave hit. But is there a direct link between the heat wave and the collapse of the ice shelf? Professor Matt King of the University of Tasmania gave an answer: “The heat wave may be one of the factors. Whether it will cause a chain reaction needs further in-depth research. But it is worth noting that the coastline of Antarctica has not been affected since the 20 It’s been going backwards since the 1970s, and the heat wave may be the final coup de grace anyway.”

So, what is the relationship between the collapse of the ice shelf, ice sheets and glaciers, and what chain reactions will it bring?

In fact, ice shelves are protruding ice floes extending from the coast to the sea, attached to land ice sheets and glaciers, and play a supporting role. Professor Matt King explained that because the ice shelf has always been floating on the water, the collapse of the ice shelf itself has little direct effect on sea level rise except for cooling the sea water. However, the ice shelf can be said to be the “safety belt” on the edge of the Antarctic ocean. The disappearance of the ice shelf is like releasing the valve on the land ice, making the land ice unstable, and the friction between the glacier and the side wall and the river bed disappears. , the direct result is to accelerate the glacier to the ocean.

It is undeniable that the collapse of the Conger Ice Shelf is a serious wake-up call given to humans by nature. Even in East Antarctica, huge and rapid changes may occur. What can be seen with the naked eye is that a large amount of sea ice has retreated in the Arctic. Although Antarctica has not yet reached this level of severity, under the intensification of global warming, it may only be a matter of time before the glaciers melt.

Not only the polar glaciers are melting, human beings need urgent action to save themselves
Antarctica’s sea ice extent hits a record low, and the climate problem cannot be underestimated. In addition to retreating glaciers, rising sea levels, and warming oceans, climate change has brought about a whole host of other responses. Through scientific data research, it is found that global warming caused by climate change has posed a huge threat to human health and survival.

Not only are the glaciers in the north and south poles melting, but since the 1920s, glaciers in Asia such as Nepal, India, Pakistan, and China have also been melting at different speeds. A study by the International Council on Snow and Ice (ICSI) states: “The Himalayan glaciers are retreating faster than anywhere else in the world. If the current rate of melting continues, there is a very high probability that these glaciers will disappear by 2035.” “. Once the glaciers in the “roof of the world” Himalayas disappear, the human living environment will undergo earth-shaking changes.

In addition, according to Paul Epstein of Harvard University’s Institute for Emerging and Relapsing Diseases, as the temperature on the top of the mountain rises, high-altitude areas will become more and more popular with microorganisms such as mosquitoes and malaria parasites. As a result, some tropical diseases will begin to attack cooler regions. Since 1987, the successive outbreaks of tropical infectious diseases such as malaria and yellow fever in Florida, the Mississippi River, California and Colorado in the United States seem to be evidence of the prophecy.

In addition, from the perspective of the law of crop growth, the temperature increase caused by climate change is not conducive to seed growth, and the temperature makes the global water circulation system disordered, which makes the precipitation increase in middle and high latitudes and floods, and the precipitation in Africa and other regions decreases and droughts occur. And both frequency and intensity are increasing. As the saying goes, drought will kill you, and flood will kill you. This will also lead to a reduction in crop production and directly affect the problem of food and clothing for human beings.

Urgent action is needed for human self-help. To slow the rate at which Antarctica’s glaciers are melting, the big problem of global warming must be addressed.

How to reduce the amount of carbon dioxide, “emission reduction” is the focus of discussion in various countries in recent years. First of all, human beings must not only protect forests, but also start planting a large number of trees to promote forest regeneration through large-scale afforestation. Secondly, in terms of carbon dioxide emissions, we should try our best to reduce the exhaust emissions produced by automobiles, as well as the consumption of fossil fuels and gasoline, and choose low-carbon travel methods such as public transportation.

Of course, human beings’ self-help behavior should also permeate into the daily life. For example: for domestic waste, do a good job of sorting and not throwing it away; for water resources, raise the awareness of water conservation and handle recycling; for energy, start with every little thing that turns off the lights; It is necessary to establish the concept of protecting biodiversity.

In Hemingway’s “For Whom the Bell Tolls”, there is such a passage: “No man is a self-contained, isolated island, every man is a part of a vast continent…Every man’s death is my sorrow , because I am a member of mankind. Therefore, don’t ask for whom the death knell tolls, it tolls for you.” We should clearly realize that the problems facing mankind in the future are the problems you and I will face.

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