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Scientists may have just figured out how to roll back climate change, the only catch?
It could cost as much as 5 trillion dollars and use more steel than the United States
produces in a year.
Hey there freezing fans, Jules here for Dnews!
Climate change is very real, and one of its biggest victims is Arctic sea ice.
Since the 1980s, the amount of ice has, on average, dropped by more than 13 percent each
decade.
But fear not!
Because according to a paper just published in the journal, Earth’s Future, scientists
may have an ingenious solution.
It involves ten million pumps.
The plan is to “refreeze” ten percent of the arctic ice cap by using giant wind-powered
pumps to cover the existing caps with salty seawater..
When the seawater is sprayed on top of frozen ice and surrounded by the -40 degree celcius
air, it freezes into new ice.
According to the paper, it would take 10 million wind-powered pumps, outputting roughly 16.5
pounds of water per second, to add 3 feet of ice over ten percent of the Arctic Ocean.
For every 4 feet of water pumped onto the surface, the ice will become roughly 3 feet
thicker, a plan that, if it works, will postpone the loss of the ice caps by about 17 years
for every year they do this.
As the researchers say, quote “Implementation over the entire Arctic in the early 2030s
… would reset the clock to the present day.”
That’s great news because at the current rate, scientists estimate the polar ice caps
will be entirely gone by 2030.
Of course, the plan isn’t easy, or economical.
Each wind turbine used to power the pump will need to be roughly 19 feet across, and use
roughly 22,000 pounds of steel.
The paper also states that ten million pumps would only really cover ten percent of the
Arctic Ocean’s roughly 4 million square mile size; to cover the entire area would
take 100 million pumps, and roughly 100 million tons of steel each year.
The US alone currently produces about 80 to 90 million tons of steel a year, so covering
just 10 percent of the Arctic ice would use around 13 percent of U.S. steel production.
The total cost would be 50 billion dollars per year, or 500 billion over 10 years -- and
again, that’s if you only cover 10 percent of the Arctic.
To cover the whole thing would be a whopping 5 trillion dollars.
But not all efforts to save the Arctic ice caps are so costly.
Another leading solution is called solar-radiation management, where sunlight is reflected away
from the ice, instead of being absorbed by it, leading to slower melting.
One method of doing this is to inject reflective aerosol particles, particularly chemicals
like sulfates, into the stratosphere.
In nature, volcanic eruptions scatter sulfate particles high into the air as part of an
ash cloud, and it has been observed that these particles reflect solar radiation back into
space and lead to cooling of the earth below it.
So if we could do this artificially, it could have the same effect.
In fact, a 2008 study found that if we could decrease the sunlight reaching the Arctic
area by about 21%, it would allow the ice to remain even if the amount of CO2 in the
air doubled.
But this solution leads to many other environmental concerns, such degradation of the ozone, which
sulfates are known to do.
It could also lead to a warming of the stratosphere, as the reflective particles would absorb some
of the heat and disperse it in the surrounding atmospheric air.
Both of these could ultimately lead to a worsening of climate change conditions.
And the aerosol in itself is air pollution, of the kind that leads to asthma and other
health problems.
Ultimately, there is no simple, elegant solution.
The paper itself admits that technology alone won’t solve our problems.
The world is still warming, the ice caps are melting, and the sea levels are rising.
Without the ice caps reflecting light away from earth, the ocean will absorb even more
solar radiation and heat, which could influence global warming.
Worse yet, the more ice is melted in the Arctic, the more methane, a greenhouse gas, will be
released into the atmosphere.
Currently that methane is trapped under the permafrost, and as that thaws, it could speed
up the effects of global warming.
While setting up 100 million pumps, or shooting sulfates into the sky may sound crazy, those
may not be as crazy as the alternatives.
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Scientists' Crazy Plan To Refreeze The Arctic

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Ntiana 2017 年 11 月 21 日 に公開

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