Op-ed: Ice Melt Drives Earth's Sea Level Rise

This is an op-ed written by an external contributor. All views expressed are the author's own.

This month, Arctic sea ice shrank to its annual minimum extent or lowest point of the melt season. Although this is not a record low, it is a stark reminder that we must act now to reduce emissions like black carbon, which are accelerating ice melt and driving sea level rise. 

A recent study published by the National Academy of Sciences shows that ice melt is the main driver of global sea level rise.

Researchers at Hong Kong Polytechnic University compiled a 30-year record tracking the water added to the seas between 1993 and 2022 which found that within that period, global sea levels rose by about 90 millimeters (3.5 inches).

Their new study strengthens confidence in how scientists monitor rising sea levels and resolves some prior uncertainty about the causes.

Their study revealed that about 60% of the sea-level rise came from added ocean mass mostly due to melting ice. Melting ice sheets and glaciers combined accounted for about 85% of all ocean mass increase, with the largest amount coming from Greenland.

This study confirms that ice melt is driving the increase in ocean levels now being experienced. Ocean levels are rising more quickly, and melting ice is the main reason.

Sea-level rise caused by the warming climate is already having big impacts on the environment, human societies and economies, especially in coastal regions.

Impacts include coastal erosion and loss of land, displacement of populations, damage to infrastructure, increased flooding, saltwater intrusion into freshwater aquifers and alteration of coastal ecosystems and habitats. 

Low-lying coastal areas such as the Pacific Islands and parts of Bangladesh, Vietnam, India and southern Louisiana are particularly at risk and already experiencing impacts that include the relocation of communities, flooding, erosion and salinization of freshwater supplies. 

As climate change continues to progress, projections show many millions of people will be adversely affected due to sea level rise.

Academic models project that up to 200 million people could be displaced by 2100, depending on the extent of global warming and the effectiveness of adaptation measures. 

The Arctic, warming far faster than the rest of the planet, is where a lot of the melting ice is concentrated. A recent report by Pacific Environment, On thin ice: Why black carbon demands immediate action, discusses the role of black carbon in accelerating the Arctic meltdown.

Black carbon is a “super-pollutant” characterized mainly by its high degree of warming potential as a powerful “short lived climate forcer.”

Its small particles have a relatively brief lifespan of a few days in the atmosphere compared to longer-lived greenhouse gases such as carbon dioxide. However, although short-lived, black carbon’s small particles are powerful warming agents with a warming impact up to 1,500 times greater than that of carbon dioxide per unit of mass. 

When released in the Arctic, its impact is amplified by the loss of albedo effect, the reduced reflection of solar energy due to the melting of snow and ice. Black carbon heats the atmosphere and accelerates melting, exposing the dark surfaces that absorb more heat, causing warming loops.

This reduces the reflectivity of the Arctic ice cap, one of the planet's most important cooling systems.

International maritime shipping is one of the big emitters of greenhouse gases and, by consuming residual fuels (the dirtiest of all transport fuels), is also a major emitter of black carbon.

Pacific Environment’s report proposes an urgently needed solution: requiring ships operating in the Arctic to reduce black carbon by burning cleaner fuels.

A rapid, large-scale reduction of black carbon emissions from ships in the Arctic can be accomplished by mandating a switch away from highly polluting residual fuels to marine distillates or other cleaner fuels.

The International Maritime Organization, which regulates global shipping, will have the opportunity to act on this issue next spring, when it should adopt a MARPOL amendment requiring a mandatory switch from residual fuels to cleaner distillate marine fuels for ships operating in the Arctic.

The IMO can enact a high-impact policy that achieves immediate benefits for the climate and human health by mandating use of cleaner fuels that cause less black carbon in the Arctic.

The IMO’s Pollution Prevention and Response 13 Sub-Committee (PPR 13) meets in February, 2026; by recommending adoption of a cleaner fuels mandate, PPR 13 can kick start the IMO’s process to address this issue.

The IMO can arrest Arctic warming, protect the marine environment and adjacent communities, and slow global sea level rise by reducing black carbon from ships in the Arctic.