Scientists test pumping seawater to slow Arctic ice loss, but questions remain

Sea ice engineers are using hydrogen-powered pumps to thicken Arctic ice, but the effort is raising concerns about effectiveness, environmental risk, and Indigenous consent.

Matilda Hay reports for Grist.


In short:

  • The nonprofit Real Ice is testing a method that pumps seawater onto existing ice to boost winter freezing, with early data suggesting it could significantly thicken ice and potentially slow summer melt.
  • Critics warn the approach may not scale to the vast size of the Arctic, could distract from emission reductions, and may bring ecological and social risks to Indigenous communities.
  • Real Ice aims to expand its experiments while seeking local partnerships, regulatory approval, and a possible global funding model akin to rainforest protections.

Key quote:

“We don’t want to repeat the kind of mistakes that have been made by Western researchers and organizations in the past.”

— Cian Sherwin, co-CEO of Real Ice

Why this matters:

Arctic sea ice acts like Earth’s reflective shield. It bounces much of the sun’s energy back into space, helping regulate the planet’s temperature. As global warming accelerates, this shield is disappearing — with the oldest, thickest ice down by 95% since satellite records began. That’s not just a polar problem: as the ice vanishes, the darker ocean absorbs more heat, fueling more warming. The changes ripple out, altering jet streams, increasing wildfire risk, and threatening biodiversity far beyond the Arctic. Efforts like Real Ice’s offer a controversial stopgap — thickening the ice temporarily in hopes of delaying its collapse. But they come with environmental unknowns and moral dilemmas: Do such strategies offer real protection, or do they let the world dodge the hard work of cutting emissions? For now, the Arctic is melting faster than humanity is adapting.

Related: Melting Arctic ice is rewriting the planet’s future

Aerial view of several rows of solar panels in a green field

COP31 host Türkiye is home to one of Europe's largest solar farms. Why can’t it kick coal?

As Türkiye prepares to host the UN climate summit, one critic describes the country's climate targets and policies as “critically insufficient”.
A yellow skid-steer loader in front of destroyed homes on January 13, 2013 in Lavallette, New Jersey in the aftermath of Hurricane Sandy
Credit: Glynnis Jones/BigStock Photo ID: 41233060

Disaster-prone communities face cuts and slowdowns in federal help

The Trump administration is scaling back or stalling investments that help vulnerable places harden themselves to rising flood and fire threats.
A view of a large ocean wave breaking

Why the blue wave brings new hope for clean energy

While affordability and inflation were top of mind for voters, midterm results will also affect climate policy at virtually every level of government.

A group of red and blue stickers with "VOTE" and "VOTE TODAY" on them

What experts think the Democratic blue wave will mean for climate action

With a new majority in the House and Senate, here's what climate experts think Democrats will prioritize.
A view of a cellphone with the Meta logo on it with the facebook logo on the wall behind it

Oil companies spent over $2M on Meta ads in the lead-up to the midterms

A look at Meta’s social issues advertising database shows that Shell, Exxon, and Chevron have long outspent environmental groups.

A view from Portland, Oregon of a bridge with a big mountain in the background

Oregon judge allows Multnomah County climate lawsuit against fossil fuel giants to advance

Gas companies sought to have the climate case dismissed, saying state governments don't have the power to regulate their interstate pollution.
View of Tetiaroa from the lagoon on a cruise ship French Polynesia
Credit: Piccola/BigStock Photo ID: 195061267

How Marlon Brando’s private island inspired a plan to suck carbon pollution from the air

A pristine atoll in the Pacific Ocean is the birthplace of a technology that could help solve a problem created far beyond its sandy shores.

From our Newsroom
Multiple Houston-area oil and gas facilities that have violated pollution laws are seeking permit renewals

Multiple Houston-area oil and gas facilities that have violated pollution laws are seeking permit renewals

One facility has emitted cancer-causing chemicals into waterways at levels up to 520% higher than legal limits.

Regulators are underestimating health impacts from air pollution: Study

Regulators are underestimating health impacts from air pollution: Study

"The reality is, we are not exposed to one chemical at a time.”

Pennsylvania governor Josh Shapiro speaks with the state flag and American flag behind him.

Two years into his term, has Gov. Shapiro kept his promises to regulate Pennsylvania’s fracking industry?

A new report assesses the administration’s progress and makes new recommendations

silhouette of people holding hands by a lake at sunset

An open letter from EPA staff to the American public

“We cannot stand by and allow this to happen. We need to hold this administration accountable.”

wildfire retardants being sprayed by plane

New evidence links heavy metal pollution with wildfire retardants

“The chemical black box” that blankets wildfire-impacted areas is increasingly under scrutiny.

Stay informed: sign up for The Daily Climate newsletter
Top news on climate impacts, solutions, politics, drivers. Delivered to your inbox week days.