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Global temperatures are rising
CLIMATE CRISIS IN ANTARCTICA
While natural climate cycles dictate we should be moving into a period of global cooling, temperatures are rising. The past three decades have been the warmest in recorded history.
The polar regions are heating up more quickly than the rest of the globe. During the second half of the twentieth century, the Antarctic Peninsula and West Antarctica warmed more than two times faster than the global average.
The ocean is heating up
CLIMATE CRISIS IN ANTARCTICA
The Fifth Assessment Report published by the Intergovernmental Panel on Climate Change (IPCC) in 2014 reported that the ocean had absorbed more than 93% of the excess heat from greenhouse gas emissions since the 1970s. Most of this was in the Southern Ocean.
Ocean warming is affecting some areas more quickly than others. The Antarctic Circumpolar Current is warming more rapidly than the rest of the world’s oceans, and upper ocean temperatures to the west of the Antarctic Peninsula have increased over 33°F (1°C) since 1955. In 2020, a study reported that parts of Antarctica’s Weddell Sea have warmed five times faster than the rest of the ocean.
Ice shelves are melting
CLIMATE CRISIS IN ANTARCTICA
As the ocean heats up, Antarctic ice is melting. Warm water is flowing under ice shelves, the floating edges of the Antarctic Ice Sheet, melting them from below. This makes the ice shelves thinner and more vulnerable to breaking apart.
In the 1980s, Antarctica lost an average of 40 billion tons of ice per year. By 2020 this had increased more than sixfold, ramping up to 252 billion tons a year. Historically, fresh snowfall and ice-loss were roughly in balance and the Antarctic Ice Sheet maintained a steady mass. Today, the rate of ice-loss is accelerating and the ice sheet is shrinking faster each year.
Sea levels are rising
CLIMATE CRISIS IN ANTARCTICA
As polar ice melts, sea levels are rising. In the year 2020, sea levels rose more than twice as quickly as they did in the 1990s.
Much of this was due to the accelerated melting of the Antarctic and Greenland ice sheets.
Exactly how much – and how quickly – these ice sheets will melt, and how rapidly sea levels will rise as a result, remains one of the greatest areas of uncertainty within climate science.
Atmospheric carbon dioxide (CO2) is increasing
CLIMATE CRISIS IN ANTARCTICA
The amount of carbon dioxide in the atmosphere is increasing, mostly as a result of burning fossil fuels. In the year 2021, there was more CO2 in the atmosphere than at any time during the past 800,000 years. The annual rate of increase is around 100 times faster than previous increases associated with natural processes, for example at the end of the last ice age 11,000 to 17,000 years ago.
As a greenhouse gas, CO2 plays an important role in keeping the Earth’s climate in balance. It absorbs and radiates heat, preventing the sun’s warmth from escaping to space. Without any CO2 in the atmosphere, the Earth would sink into an ice age. When CO2 levels rise, temperatures follow.
Ocean acidification
CLIMATE CRISIS IN ANTARCTICA
As carbon dioxide levels in the atmosphere increase, the ocean is becoming more acidic. This is because the ocean absorbs excess carbon dioxide from the atmosphere, and a series of chemical processes make the ocean more acidic as a result.
A more acidic ocean is already having an impact on many marine organisms, particularly those that build shells. Exactly how ongoing ocean acidification will impact Antarctic ecosystems is an active area of research.
Biodiversity is under threat
CLIMATE CRISIS IN ANTARCTICA
As the Earth’s climate becomes warmer and more extreme, animals are forced to adapt to rapidly changing conditions. Across the globe, many hundreds of species are predicted to become extinct within the next 20 years.
Antarctic species are particularly vulnerable to a warming climate. Their highly specialized adaptations, which allow them to survive and thrive in the polar environment, make them less resilient as the ocean warms and ice melts. With their habitats and food sources under threat, they are in urgent need of protection.
CLIMATE CRISIS IN ANTARCTICA
It affects us all
The climate crisis is having widespread impacts on the ocean, ice and wildlife that make Antarctica the unique and precious place it is today. These changes will also have flow-on effects for all of humanity.
Impacts on humans
Climate Crisis in Antarctica
The climate crisis is already changing the shape of Antarctica. These changes affect us all, with far-reaching effects from rising sea levels to more frequent extreme weather events, and changes to the ocean currents that set the global climate thermostat.
These changes threaten human civilization by destabilizing the natural systems we depend on for food, water and security. This situation is caused by human activities such as burning fossil fuels, clearing land, and large scale agriculture.
It’s not too late to change our trajectory. Now is the time to take urgent action to secure a climate-safe future for humanity.
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Climate Crisis in Antarctica
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Now that you’ve learned how Antarctica is changing in response to the climate crisis, read on to learn more about extraordinary Antarctica.
