In a new study, experts say high-flying aircraft could spray tiny aerosol particles into the atmosphere at latitudes 60 degrees north and south. If released at an altitude of 43,000 feet (above aircraft cruise altitudes), these aerosols would slowly drift poleward, lightly shadowing the surface below. This extra shade would allow the melting poles to refreeze, alleviating the problems of melting glaciers and rising sea levels. The technique would “reduce climate change by diverting a small fraction of incoming solar radiation back into space,” the scientists say. The idea, called stratospheric aerosol injection (SAI), would cost $11bn (£9.6bn) a year – but researchers say this would be cheaper than other climate mitigation methods. Researchers propose a system of high-flying jets that spray tiny aerosol particles into the atmosphere at latitudes 60 degrees north and south
STRATOSPHERIC AEROSOL INJECTION (SAI)
Scientists put forward an idea whereby high-flying jets would spray tiny aerosol particles into the atmosphere at latitudes 60 degrees north and south.
If injected at 43,000 feet (above aircraft cruising altitudes), these aerosols would slowly drift poleward, slightly shadowing the surface below.
The technique would “reduce climate change by diverting a small fraction of incoming solar radiation back into space,” the scientists say.
The idea has been formulated in a new study, published in Environmental Research Communications and led by Wake Smith at Yale University.
The researchers acknowledged that the idea is controversial, but argued that it would be “feasible” and that $11 billion a year is “extremely cheap” compared to other climate responses, such as carbon sequestration.
“There is widespread and reasonable fear of developing aerosols to cool the planet,” said Smith, a lecturer at Yale.
“But if the risk/benefit equation paid off anywhere, it would be at the poles.”
Cooling at the poles would provide immediate protection for only a small part of the planet, although mid-latitudes should also see some cooling, the team admits.
“Nonetheless, any deliberate turning of the global thermostat would be of common interest to all of humanity, not just the province of Arctic and Patagonian nations,” Smith said.
According to Smith and colleagues, particle injections from the jets would occur seasonally during the long days of local spring and early summer.
The same fleet of jet aircraft could serve both hemispheres, switching to the opposite pole with the change of seasons.
Pre-existing military air-to-air refueling aircraft such as the aging KC-135 and A330 MMRT do not have enough payload at the required altitudes. However, newly designed high-altitude tankers, including one called the SAIL-43K, will prove more effective, the team says
The blankets of aerosols would stretch 60 degrees north and south – about the same level as Anchorage, Alaska, and the southern tip of Patagonia.
Pre-existing military air-to-air refueling aircraft such as the aging KC-135 and A330 MMRT do not have enough payload at the required altitudes.
However, newly designed high-altitude tankers, including one referenced in the study called the SAIL-43K, will prove more effective, the team says.
A fleet of about 125 such tankers could lift a payload enough to cool the poles by 3.6°F (2°C) annually, which would return them to near their pre-industrial average temperatures.
The $11 billion a year cost is less than a third of what it would cost to cool the entire planet to the same 3.6°F and a tiny fraction of the cost to achieve net zero emissions, experts say.
However, the plan is not without drawbacks – the aircraft would of course release its own emissions, which would contribute to global warming.
This extra shade would allow the melting poles to refreeze, alleviating the problem of melting glaciers and in turn rising sea levels. In the photo, the ice in the Arctic is melting
In addition, the aerosol will consist of sulfur dioxide, which at high levels can cause nausea, vomiting, stomach pain and corrosive damage to the airways and lungs.
According to experts, less than 1 percent of the world’s human population lives in the target development zones, so the risk to most of humanity is small.
Smith also acknowledged that the idea would not address the root causes of climate change. rather, he would rather be something like a sticking plaster for Earth.
“The game is changing, although this could be happening in a rapidly warming world, stratospheric aerosol injections are just treating a symptom of climate change but not the underlying disease,” Smith said.
“It’s aspirin, not penicillin. It is not a substitute for decarbonisation.”
Unfortunately, potential methods of dealing with the issue of melting glaciers and rising sea levels are becoming increasingly urgent as the poles are warming many times faster than the global average, studies have shown.
ARCTIC IS WARMING ALMOST FOUR TIMES FASTER THAN REST OF WORLD, STUDY REVEALS
The Arctic is warming nearly four times faster than Earth’s average – up to twice as fast as previously described, according to a 2022 study. The researchers analyzed multiple data sets from NASA and the Met Office on Arctic Circle temperatures between 1979 and 2021. They found that a large percentage of the Arctic Ocean warmed at a rate of 1.35°F (0.75°C) per decade during this period, nearly four times faster than the global average. Previous studies indicate that the Arctic is warming either twice, or more than two or three times faster than the global average. Temperatures are rising faster in the Arctic than in the rest of the world, mainly due to the loss of sea ice. When the bright and reflective ice melts, it gives way to a darker ocean. This reinforces the warming trend because the surface of the ocean absorbs more heat from the sun than the surface of snow and ice. read more
