The Arctic on the edge

As the ice sheet shrinks, its gravitational pull on surrounding ocean water weakens, causing local sea levels to drop, writes B K Singh.

The Arctic is warming four times faster than the global average — a phenomenon called Arctic amplification. As sea ice retreats, dark ocean water absorbs solar radiation rather than reflecting it.

Warmer Atlantic and Pacific currents push into the Arctic, while heat trapped near the surface cannot rise because vertical circulation is weaker at the poles than in the tropics.

A warmer atmosphere holds more water vapour, itself a potent greenhouse gas.

Thawing permafrost releases methane and carbon dioxide, compounding the feedback. The Arctic is not just responding to climate change — it is accelerating it.

The retreat of sea ice has opened shipping lanes that were once impenetrable, and the boom in maritime traffic is adding to the crisis. Ships emit black carbon, or soot, which settles on ice and reduces its reflectivity. Clean ice reflects up to 80% of solar radiation; soot-covered ice reflects barely half that.

In 2024, the International Maritime Organisation (IMO) proposed requiring ships north of 60°N to use cleaner polar fuel, but adoption remains limited.

France, Germany, Denmark, and the Solomon Islands have since pushed for stricter regulations, likely to come before the IMO’s Pollution Prevention and Response Committee in April.

Meanwhile, the United States is moving in the opposite direction. The Arctic National Wildlife Refuge — 1.5 million acres of pristine habitat in northern Alaska, home to nearly 200 wildlife species and the ancestral lands of the Inupiat and Gwichin peoples — has been opened for oil and gas drilling.

Over 300 km of roads, blocked under the previous administration, have been ordered to be built to facilitate operations. Federal funding for Arctic climate research has been slashed.

An annual assessment by the US National Oceanic and Atmospheric Administration found that surface air temperature between October 2024 and September 2025 was the highest since records began in 1900.

Toxic minerals have flooded rivers across northern Alaska, and last winter’s sea ice reached its lowest annual maximum extent in 47 years. Erik Grafe of Earthjustice called it a sacrifice of unique landscapes to the oil industry at precisely the wrong moment in the climate fight.

The science being ignored is sobering. A team led by geophysicist Lauren Lewright at Columbia University has documented a counterintuitive phenomenon around Greenland: sea levels there are actually falling. Greenland is 80% covered by a mile-thick ice sheet that has literally depressed the landmass beneath it.

As that ice melts — at roughly 200 billion tons per year — the land rebounds. The study estimates that Greenland is projected to gain 0.9 metres of newly exposed coastline by 2100.

But the relief is an illusion. As the ice sheet shrinks, its gravitational pull on surrounding ocean water weakens, causing local sea levels to drop even as global levels rise. For coastal communities, reduced sea levels bring their own disruptions to food security and livelihoods. And if Greenland’s ice sheet were lost entirely, global sea levels would rise 2.5 metres.

Far from the ice, another climate buffer is under stress. Peatlands cover just 3% of Earth’s surface but store 600 billion tons of carbon — more than all the planet’s forests combined. As the Arctic warms, a process called Arctic greening is underway: receding ice exposes darker ground, which absorbs more heat, thereby enabling plants to advance northward into newly warm terrain.

Paleo-ecologist Josie Handley, lead author of a recent study, notes that things are getting greener and wetter. But the thawing permafrost beneath is releasing ancient carbon long locked in frozen soil. Extreme heat drives massive wildfires through shrubs, trees, and dried peat.

Biogeochemist Angela Gallego-Sala of the University of Exeter is blunt: “We are already in extreme dry years, the peatlands are going up in fire.” Carbon sequestered over millennia is returning to the atmosphere in seasons.

In the waters between Greenland and Canada, another fragile system is at risk. North Water Polynya — an expanse of ocean within Baffin Bay that never freezes — is sustained by converging currents and a natural ice arch to the north that holds back sea ice.

The polynya produces nutrient-rich waters that support extraordinary biodiversity and the Inuit communities who have depended on it for generations. With unprecedented Arctic warming, the ice arch sometimes fails to form. The Inuit have urged the Canadian and Greenland governments to establish a marine protected area before the window closes.

The Arctic is not simply a distant ecosystem in distress. It is a system of systems — ice, ocean, permafrost, peat, people — each one interlinked, each one under pressure simultaneously.

Decisions made in Washington, Brussels, and Beijing echo at the poles. The science is unambiguous; what remains is whether politics will catch up before the feedbacks become irreversible.

The author is a former head of Forest Force, Karnataka, and an environment commentator.