OVER the past few weeks, Alaska recorded record-high temperatures, scientists released a “report card” showing relentless deterioration of the Arctic’s climate, and researchers warned that an ice shelf in Antarctica could collapse within a few years, dramatically increasing the region’s contribution to rising sea levels.
These are signposts on a grim path. They show that damage to the cryosphere, the portions of Earth’s surface where ice predominates, is happening faster than many anticipated. After a year of promises — at the United Nations’ Glasgow climate conference and beyond — 2022 must be the year of concrete action, in particular at the Earth’s poles.
The annual Arctic health check produced by the US National Oceanic and Atmospheric Administration provided a worrying snapshot. For the eighth year in a row, surface air temperatures in the High North were at least 1 degree Celsius (1.8 degrees Fahrenheit) above the long-term average. In April, the post-winter volume of sea ice — a crucial indicator — hit the lowest level since record-keeping began.
Since 1980, the Arctic has warmed nearly four times faster than the rest of the globe. This is partly due to feedback loops. Retreating sea ice exposes darker ocean, which absorbs sunlight rather than reflecting it, and hence causes more melting. It’s a similar story with thinning ice sheets and shrinking snow cover. Permafrost — which holds twice the present-day atmosphere’s load of carbon — is now thawing and releasing methane, which in turn is heating the atmosphere and worsening the thaw.
Antarctica tells a similar tale. An ice shelf has held the giant Thwaites Glacier in place like a cork, but researchers last month said warm water was melting it from below, while the grip of an undersea mountain that has pinned it in place is loosening. Increased fracturing could simply shatter it. If the Thwaites Glacier melted entirely, it would raise global sea levels by about two feet, threatening coastal cities.
What’s to be done?
Global emissions reduction is of course essential. But those efforts won’t do enough to forestall a looming crisis in the polar regions. Policy makers should view the cryosphere as a test bed for the kind of large-scale technological interventions that may soon be needed in other areas as climate change intensifies.
As a start, that will require a more robust governance forum for the poles. Existing frameworks — notably the Arctic Council and the Antarctic Treaty — have helped keep the peace and advance scientific goals, but neither is suitable for making political choices. An effort under the UN’s auspices to oversee climate technology at the poles could help lay the groundwork for significant new experiments.
Several such projects are already under study. Some are clever if far-fetched, such as a plan to coat seasonal Arctic ice with a reflective glass powder, thereby increasing its reflectivity and diminishing feedback loops. Some are plausible but require further study and risk assessment, such as efforts to deploy hydrosols to increase surface-water brightness; use wind power to pump water to the surface during the Arctic winter, where it should rapidly freeze and thicken; or inject sulfates into the lower stratosphere to reduce temperatures and ice loss.
A few proposals seem potentially transformative. One plan, published by four scientists in Nature, envisions constructing large barriers at the base of glaciers that could block warm ocean currents and prevent the underlying ice from thawing. The authors propose using berms and artificial islands to buttress ice shelves and impede sea-level rise. If successful, they estimate, such efforts could delay catastrophic melting by several centuries — buying crucial time for emissions reduction to take hold.
All these approaches will have drawbacks. Some won’t work. None should reduce the urgency to slash carbon emissions. But solving climate change requires experimentation, boldness and openness to new ideas — even those that may sound slightly unhinged.