Polar bears are veritable Arctic overlords, with the power of their palms breaking through the ice and even damaging beluga whales with a single blow. Such a powerful and beautiful Arctic spirit, due to the rise in global temperature and the gradual melting of the Arctic ice floes, has led to the destruction of its former homeland, which is likely to become extinct in the near future.
Above: A polar bear stands on melting sea ice near the Hubble Islands in Canada.
In fact, this future is not very far away. According to a new study published in the journal Future of Earth, if the world's carbon emissions continue to follow their current trajectory, the worst-case scenario could be that by 2100, the summer ice in the Arctic will be completely over and the Arctic will completely die out. Polar bears, seals and other small Arctic animals that live on them will disappear.
Above: Polar bear and its cubs
Arctic sea ice has been steadily decreasing since satellite records began in 1979, but there has always been a "final ice zone" that serves as a habitat for Arctic life. This is the oldest and thickest area of Arctic ice. Spanning Canada and northern Greenland, it covers an area of more than 1 million square kilometers, with ice layers as thick as 10 meters and four stories high.
Above: Sea ice north of the Canadian Arctic Archipelago, which is too thick for ship icebreakers to pass.
But in May 2020, a huge hole appeared in the Arctic's oldest and thickest ice. Meanwhile, in the summer of 2020, the eastern part of the Last Ice lost more than half of its icing layer. While scientists previously thought the ice zone was the most stable in the Arctic, the huge fissures suggest that ancient ice layers have become easily melted. It is estimated that even if we manage to control global carbon emissions as stipulated in the Paris Agreement, summer sea ice in the Arctic will be "thinner, younger and more fluid."
Above: A hole in the Arctic ice that broke for about two weeks.
The significant reduction in ice-covered areas could have a serious impact on the survival of the animals that inhabit them, including photosynthetic algae, small crustaceans, fish, seals, narwhals, bowhead whales and polar bears. The Arctic is the arctic's top predator, feeding mainly on seals and occasionally catching walruses, beluga whales, seabirds, fish, and small mammals. This means that if the ice disappears, polar bears are the most vulnerable and particularly vulnerable to extinction.
Above: A polar bear inhabits the sea ice of the Chukchi Sea between Alaska and Russia.
In addition, the situation in the tropics is not optimistic. According to a new study published in Nature Communications in September 2021, plankton are undergoing global migration, escaping waters where the tropics have become too warm to live, and gradually moving toward the polar regions. The researchers found that if the average sea surface temperature reached above 25 degrees Celsius (the current long-term average is 16.1 degrees Celsius), plankton in the tropics would be greatly reduced, and all species would shift to colder waters at higher latitudes. Since these plankton are at the bottom of the ocean food web, this trend has the potential to destabilize the fragile ocean food web and alter the ocean as we know it. What's more noteworthy is that we may not be able to change this trend and are doomed to fall into the abyss.
Above: Plankton
According to a new report released by the United Nations, despite a series of new climate commitments, global warming will still reach catastrophic levels in the future, and now disasters are getting closer and closer to us. At present, there are three main greenhouse gases that affect climate problems, namely carbon dioxide, methane and nitrous oxide.
Carbon dioxide is the most important, accounting for about 66% of the warming effect. By 2020, carbon dioxide concentrations have reached 413.2 parts per million, 149% of pre-industrial levels in 1750. The average nitrous oxide was 333.2 ppb, which is now 123% of the 1750 level. The worst is methane, which averaged a new high in 2020 at a pre-industrial 262%.
Moreover, according to a new study published in the journal Nature on July 14, the Amazon rainforest, known as the "lungs of the earth", has also been "suffocated", completely abandoned, and has become a source of carbon dioxide emissions, which is exacerbating global warming. This is the first time scientists have confirmed that the Amazon rainforest releases more carbon dioxide than absorbs each year.
Since the 1960s, about a quarter of the greenhouse gases emitted by fossil fuels have been absorbed by trees and other plants on Earth. As the largest tropical rainforest on Earth, the Amazon rainforest has always played a major role in absorbing greenhouse gases. Now it is burned down because of human greed.
As a result, the United Nations warned in its report that the world would warm by 2.7 degrees Celsius by 2100 if countries did not have stronger plans to reduce emissions. This increase has far exceeded the goal of the Paris Agreement signed by countries in 2015, that is, to limit the increase in global average temperature in the 21st century to 2 degrees Celsius, and to control global temperature rise within 1.5 degrees Celsius above pre-industrial levels. It is important to note that global warming of 2.7 degrees Celsius would mean a catastrophic reshaping of the planet.
In the country's emission reduction plans, the biggest variable is probably Australia. As the second highest carbon emitter among the OECD countries (composed of 38 member countries), because it has long relied on energy to "make a living", it has always been very resistant to environmental protection issues, unwilling to join the team of energy conservation and emission reduction, and has maintained the carbon emissions plan of many years ago - reducing carbon emissions by about 26% by 2030. It was not until October 26, local time, that it finally could not withstand the pressure of the world and promised to achieve net zero carbon emissions by 2050. But with the country's bad deeds, I am afraid that he will not practice just by talking.
Joe Fontaine, a lecturer at Murdoch University in Australia, said: "Bringing such an empty policy to Glasgow will further cement Australia's reputation as a laggard and liar on climate change issues. Bill Hale, a climate scientist and CEO of climate analysis, a nonprofit science-policy research institute, said the Australian government's plan lacked details and was "absolutely unlikely" to help Australia achieve "net zero carbon emissions" by 2050, arguing that it was close to a hoax.
To ensure that humanity can move towards a bright future, the United Nations strongly points out that the continuous burning of fossil fuels by human beings over the years has caused global temperatures to rise by 1.1 degrees Celsius compared to before the Industrial Revolution, and will continue to rise in the next two decades, with a level of change of 1.5 degrees Celsius. Under this doomed trajectory, the occurrence of extreme weather around the world will become more frequent and pronounced. This summer, the continued heat in North America, torrential floods in Western Europe and East Asia, and forest fires in Siberia and the Eastern Mediterranean are just a preview of this future.
So in order to avoid these disasters, how do humans need to control carbon emissions? In fact, data have shown that since 1850, humans have emitted 2.4 trillion tons of carbon dioxide, and at most they can only emit another 400 billion tons of carbon dioxide, and there is a 66% chance that the temperature rise can be controlled at 1.5 degrees Celsius. That is to say, under the condition of a temperature rise of 1.5 degrees Celsius, we have already consumed 86% of the carbon budget, and if the remaining 14% cannot be effectively controlled, extreme weather such as high temperatures, cold waves, heavy rains, floods, typhoons and other extreme weather will become the norm in the future.
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