Geoengineering is often presented as a last-ditch technological solution to the climate crisis that could still step in and save the day.
But new models suggest that such risky measures, such as dimming the sun, are not enough to save Antarctica now.
There is only one thing left to do, and it is the same thing we have failed to do for 40 years now: stop burning fossil fuels.
In the face of catastrophic fires… Floods and other extreme weather events Plagued by summer in the Northern Hemisphere, there has been renewed interest in the possibilities of geoengineering. The incentive to try potentially dangerous solutions will grow stronger as climate-induced disasters intensify.
“The window of opportunity to limit global temperature rise to below 2 degrees is closing rapidly, so technical measures to influence climate in the future may be seriously considered,” says Johannes Sutter, a glaciologist at the University of Bern.
So Sutter and his colleagues decided to investigate the effect of the sun’s dimming on one of the rapidly approaching climate tipping points that researchers care about most.
“Observations of ice flows in West Antarctica indicate that we are very close to or have already passed the so-called tipping point,” explains Suter. “So with our study we wanted to find out whether ice sheet collapse could occur.” “Theoretically it can be prevented by managing solar radiation.”
The region is already missing significant amounts of ice, even though it is currently the middle of winter there. This includes a reduction in sea ice that blocks the West Antarctic glaciers on Earth. Melting of West Antarctica would raise sea levels by metres, and all that extra freshwater in the sea could also contribute to the collapse of ocean currents, which are already slowing.
The melting is happening faster than expected and is already decimating wildlife.
Sutter and his colleagues simulated ice sheet conditions under high, medium, and low emission pathways and four different stratospheric aerosol injection scenarios.
While the researchers’ models have shown that dimming the sun by spraying millions of tons of sulfur dioxide into the stratosphere by 2050 could delay ice collapse, it would only work with carbon removal and only in moderate or low emissions pathways.
“As long as greenhouse gas concentrations in the atmosphere remain high, solar radiation management is likely to continue for centuries, perhaps even millennia,” the researchers explain.
if Sun blocking management strategies If we stop suddenly we run the risk of terminal shock, where there will be a sudden increase in temperature with more serious consequences. In addition to other problems caused by increased carbon dioxide2 In our atmosphere it will continue unabated.
“Managing solar radiation could have impacts on regional weather patterns harmful to society and the biosphere and other as-yet-unknown impacts, while not addressing the direct harmful effects of rising atmospheric carbon dioxide.”2 Such as ocean acidification,” Suter and his team wrote.
Moreover, the only scenario that revealed an opportunity to stop the collapse of the West Antarctic ice sheet involved reducing carbon emissions.
“Our simulations show that the most effective way to prevent the collapse of the West Antarctic ice sheet in the long term is to remove carbon rapidly,” Suter warns.
This research was published in The nature of climate change.