Injecting aerosols into the stratosphere can refreeze Earth's poles

Injecting aerosols into the stratosphere can refreeze Earth’s poles

  • Scientists Believe Tank jets can spray sulfur dioxide mist into the upper atmosphere above Earth’s poles to help it refreeze.
  • The study says Earth’s poles could be cooled by about two degrees Celsius, at a cost of about $11 billion a year.
  • But this proposal carries risks, and it’s not an end-to-end solution to climate change – just a band-aid.

In the face of the growing threat of global warming, scientists continue to devise new concepts for stabilizing Earth’s temperatures. The latest participant is a plan published in Environmental Research Communications Which calls for high-altitude tankers to spray aerosol particles over the Earth’s subpolar regions. Once in place, it will help divert incoming solar radiation.

🌏 Want to keep up with the latest Earth news? Learn with us – Join Pop Mech Pro.

Stratospheric aerosol injection (SAI), as the study calls it, presents a “potential climate intervention that would limit global warming by slightly increasing the reflectance of Earth’s upper atmosphere.”

The SAI concept is nothing new, but this proposal calls for aerosols to be targeted in places where significant sea-level rise could potentially cause sea level rise across the planet. As Earth’s poles warm over time, the study calls for “injection of sulfur dioxide (SO2) … which will oxidize into sulfuric acid (H2SO4) and coagulate in a supercooled liquid aerosol after a month in the stratosphere.”

This is expected to reduce temperatures at the poles by two degrees Celsius. That’s enough cooling to help refreeze the polar extremes and return average temperatures to what they were before the industrial age. The adverse effects of climate change, such as extreme weather and massive floods, may be slowed.

“Subpolar spread would rapidly envelop the poles as well and could halt or reverse thawing of ice and permafrost at high latitudes. This would provide a global benefit by delaying sea level rise,” lead author Wake Smith wrote in the study. Yale College and Senior Fellow at Harvard Kennedy School.Unlike previous aerosol plans, which would cover the entire Earth, the plan Smith proposes focuses only on latitudes beyond 60 degrees north and south (think north of Anchorage, Alaska, and southern Patagonia).

“Because the tropopause is so low at high latitudes, that neither aerosols nor their precursors need to rise as high, reducing engineering challenges for global spread,” Smith wrote.

In order to work, the study specified that the aerosol would have to be released at an altitude of at least 13 kilometers, or 43,000 feet above the ground — an altitude lower than what is required elsewhere in the world by other SAIs plans. To compensate for the greatest amount of solar radiation, a specialized fleet of about 125 aircraft will operate during the very long spring and early summer in one hemisphere before traveling to the other pole to perform the same tasks.

There is only one hitch: the release of the necessary aerosol payload at this altitude is beyond the capacity of any existing carrier aircraft. The researchers have narrowed down the potential aircraft to the Boeing KC-135R, Boeing KC-46A Pegasus, Airbus A330 MRTT, Boeing KC-10, and Airbus A340F — but all of these will still need modifications for the mission. Ideally, a purpose-built “top” aircraft, called the SAIL-43K, which is based on sail 01 the design.

By focusing efforts on the poles, the plan will drastically reduce costs compared to other hardware plans, according to the study, at an annual cost of just $11 billion. This is well below the projected annual cost of $36 billion to lower surface temperature by the same degree over the entire Earth instead.

Of course, the less generous discharge of aerosols also helps resolve obvious concerns about particles dumping into the atmosphere. Will the aerosols have an unexpected environmental impact on Earth, if delivery can lead to further depletion of the ozone layer? “There is a widespread and reasonable fear of aerosols spreading to cool the planet, but if the risk-benefit equation pays off anywhere, it’s at the poles,” Smith says. This plan will reduce the risks, as less than one percent of the population lives within those areas.

Polar Bear, Expulsion Bay, Nunavut, Canada

A polar bear swims beside a melting iceberg near the Arctic Circle in Hudson Bay, Canada.

Paul Souders//Getty Images

The concept of stratospheric aerosol injection comes with a bunch of unknowns. Along with creating the best aerosol to use – the latest study sticks to sulfur-based aerosols – scientists aren’t sure of the best delivery method or for how long the aerosol will provide benefits once released. Could we finally see giant sulfur dioxide rockets firing over other continents to slow global warming, as in the futuristic geoengineering novel Termination shock by Neil Stevenson? Probably not, but this may be the first step.

In addition, this SAI proposal is by no means the ultimate solution to climate change. “The rules of the game are changing. Although this may happen in a rapidly warming world, stratospheric aerosol injections treat only a symptom of climate change but not the underlying disease,” Smith says. “It is aspirin, not penicillin. It is not a substitute for decarbonization.”

While it is still conceptually preliminary, the study authors believe the idea warrants exploration. “Given its obvious implementation potential and low cost,” they wrote, “this scenario deserves further attention.”

#Injecting #aerosols #stratosphere #refreeze #Earths #poles

Leave a Comment

Your email address will not be published.