January 11, 2022
  • January 11, 2022

you really should have a glacier-induced meltdown | Test

By on January 10, 2022 0

We’ve all heard the tragic stories of glaciers in peril: pieces of ice, the size of a continent, break away from Antarctica or melt into the Arctic Ocean near the North Pole, leaving polar bears starving and searing. ‘clinging to the remnants of collapsing sea ice. .

What is more difficult to understand is what all of this means for people living in temperate places. While these dispatches from Earth’s far polar extremes may seem far removed from our reality, understanding our relationship with these colossal icy giants is crucial to our own climatic awakening. Learning about the vulnerability of glaciers can guide our fight to stop climate change and inform ways to change course before it’s too late.

The glaciers that surround us today are remnants of Earth’s last ice age, which ended 12,000 years ago. During this time, all of Canada and much of the northern United States was completely covered in ice. New York, at the height of the last ice age, had a vertical mile of ice towering over its surface. Today, only a small fraction of that ice remains, with glaciers covering about 10 percent of the Earth’s land surface. However, they remain essential players in the stabilization of the Earth’s climate and ecosystems. Glaciers are white, which helps reflect solar heat back into space, and they’re cold, two attributes that help cool our planet. But their most important gift to us might be fresh water. 98% of the Earth’s water is found in the oceans, salty and unusable for our daily needs. Three-quarters of the tiny amount of fresh water we have on the planet – the water we really need – is stored in Earth’s more than 200,000 glaciers. In addition, new snow containing fresh water that falls on a glacier, thanks to the glacier’s cool microclimate, can survive year round, providing continuous fresh water downstream, while snow that falls elsewhere melts in spring and is quickly consumed by the ecosystem. You can imagine a glacier like a water tap, left slightly open for us, allowing us to enjoy the water all year round.

The melting of glaciers is nothing new. In fact, we enter and exit Ice Ages every 100,000 years or so, as fluctuations in the shape and tilt of the Earth’s orbit around the sun push parts of the Earth away from the sun, making them more cold and moving other parts of the Earth closer to the sun, warming them. Water sucked from the oceans by evaporation is converted to snow, which falls on the colder regions of the planet and remains frozen as long as the cold persists. If the cold climate stays long enough, you get great glaciers and an ice age that can last for 80,000 years. All of this ice making is taking a lot of water out of the ocean, and the sea level is dropping as a result. Then orbital conditions change again, ice melts, and glaciers return colossal amounts of water back to the oceans, flooding coastal lands again. You can see evidence of this cycle in the financial district of downtown Miami, where remains of coral exposed 15 feet above current ground level prove the area once stood at the bottom of the sea, at an earlier historic moment on Earth when glaciers melted much more than they have now – a worrying tale to us of what is yet to come.

Although this pattern occurs naturally every 100,000 years, human activity accelerates the melting of glaciers so rapidly that the collapse of glaciers – a process that should have lasted for thousands of years – occurs within decades, if not faster. Much of the damage we have already caused will be irreversible for millennia. Antarctica’s Thwaites Glacier recently began to collapse and pieces are now floating in the ocean and melting rapidly. Its disappearance could trigger a further destabilization of the surrounding glaciers, and raising the level of the world’s oceans of several meters.

Human activity is accelerating the melting of glaciers so rapidly that the collapse of glaciers – a process that should have taken thousands of years – occurs in just a few decades.

Today, glaciers cover an area of ​​approximately 5.8 million square miles. It’s bigger than the United States, at 3.8 million square miles. If all that ice was one country, the “Glacierland,” it would be the second largest on Earth, behind only Russia at 6.6 million square miles. If the largest glaciers are found mainly in the polar regions or in Greenland, a significant number remains closer to home, in high altitude environments such as the Rocky Mountains, the Sierra Nevada in California, Nepal, the central Andes, the Tian Shan mountains of Asia and the European Alps. There are even glaciers in Africa, on the equator and in the South Pacific. There is still a lot of water to melt in climate-vulnerable glaciers. And the rapid sea level rise they cause could cause massive flooding over millions of acres of coastal land, displacing hundreds of millions of people over the next century. If all the remaining ice in the glacier melts, the the sea would rise about 230 feet!

But rising sea levels are not the only impact of melting glaciers. The rapid melting of glaciers creates a feedback loop. As glaciers warm, the climate impact on Earth is magnified, accumulating on itself, accelerating warming and accelerating deglaciation. This is because when white glaciers melt, the darker surfaces of Earth (on land and in the oceans) absorb solar heat instead of reflecting it back into space. Think about the effect of wearing a dark shirt on a very hot day, but on a planetary scale. This, in turn, melts the glaciers even more and the Earth heats up even faster.

Ironically, the rate at which glaciers are melting is also reducing our global supply of fresh water. As glaciers shrink, the reliable fresh water they provide to ecosystems, agriculture, industry and domestic use also decreases. Smaller glaciers mean there is less ice to melt each year. The melting of glaciers, especially those perched on mountains, is also another type of danger when they lose their physical integrity. Ice structures weaken as they heat up, fracturing, collapsing, and rolling down mountains, carrying rocks and debris with them that can carry anything in their path. I call these “glacial tsunamis,” and they are increasingly common in places like the Himalayas and the central Andes, where thousands of people have died in massive landslides and ice in recent years.

Melting glaciers also wreak havoc over time. Have you ever noticed that most of Europe is on the same latitude as Canada, and yet is not as cold in winter? This is because currents in the ocean and the atmosphere move warm water and air from the equatorial regions of the Earth through the Arctic and Antarctica, where the air and water cool. before returning to the equator (as an oceanic and atmospheric conveyor belt / AC system). The ocean has a natural churning and circulating effect that is in perfect balance to keep global temperatures stable. If glaciers melt and deposit too much fresh water in salty seas, ocean water circulation and air currents can stall, leaving cold water and cold air in the polar regions and hot water and hot air near the equator. This break in the ocean’s “conveyor belt”, so to speak, could be tragic for local climate systems across the planet, sending the tropics into extreme heat and regions like Europe into a deep freeze.

My work exploring how glaciers influence our ecosystem has shown me how these rapidly shrinking ice sheets impact our entire lives. But it also made me understand that we should not be resigned to this future. It is not too late to slow, stop and even reverse climate change. We can save the glaciers and prevent a worsening of the climate emergency. I recently returned from the World Climate Summit in Glasgow, where 108 world leaders is committed to collaborate reduce methane emissions by 30% by 2030. Since methane is 86 times more powerful than carbon dioxide as a greenhouse gas, this is a big step towards slowing global warming, saving glaciers and restoring our climate.

The COVID containment has also shown us that we are able to limit our use of carbon and other so-called “super pollutants” that are even worse for the climate than CO.2, such as methane, carbon black, dirty refrigerants and smog. While before the pandemic, the idea of ​​stopping everything to save our climate would have been unthinkable, we actually stopped everything to fight COVID. With driving, air travel and the industry at rest, for example, we have eliminated black carbon emissions from the atmosphere. Carbon black, or soot as it is more commonly known, causes serious respiratory illness in humans and also plagues the environment, darkening glaciers and accelerating the melting of ice. With the sky suddenly clear of this pollutant during COVID, some residents of Nepal and India, who had lived their entire lives under a cloud of smog, saw the snow-capped Himalayas for the first time.

The positive effects of COVID on our environment and on the climate emergency were temporary – and as COVID restrictions eased, we resumed operations as usual and the benefits wore off as quickly as they had been. materialized. Nonetheless, the temporary spike in climate health has proven that collective action to give nature a break and fix our climate is possible. We are all actors involved in our global climate and each of us has the individual power and choice to make good climate decisions which can have enormous collective benefits.

We just need to realize how urgent our climate emergency really is.

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