Mercury Pollution in Antarctica Is Rising as Glaciers Continue to Melt

The rapid melting of Antarctica’s glaciers is doing more than reshaping one of the world’s most remote regions. Scientists have discovered that it is also releasing mercury that has remained trapped beneath ice and frozen soils for centuries. This newly identified consequence of climate change is turning parts of Antarctica into an emerging source of toxic pollution with potentially serious impacts on marine ecosystems and the global environment.

A recent study published in the Proceedings of the National Academy of Sciences (PNAS) found that mercury accumulation in the Antarctic Peninsula has increased by 160% since the Industrial Revolution, largely driven by glacier retreat and rising global temperatures.

Mercury Locked Away for Centuries

Mercury enters the environment through both natural processes and human activities, including fossil fuel combustion, mining, and industrial emissions. Over hundreds and even thousands of years, significant amounts of this toxic metal became trapped in Antarctic glaciers and permanently frozen ground, effectively storing the contaminant away from the environment.

As temperatures continue to rise, however, glaciers are melting at an accelerating rate. Meltwater carries the stored mercury into rivers, coastal waters, and eventually the Southern Ocean, where it re-enters natural environmental cycles.

Research Covering Two Centuries

To better understand how mercury levels have changed over time, an international team of researchers analyzed 16 sediment cores collected across the Antarctic Peninsula and its continental shelf. Using geochemical and isotopic techniques, the scientists reconstructed mercury deposition over the past 200 years.

Their findings show that Antarctica’s continental shelf currently accumulates around 93 micrograms of mercury per square meter each year, a rate that exceeds many other continental shelf regions despite Antarctica’s geographical isolation.

The study demonstrates that even the planet’s most remote environments are not immune to pollution generated by human activity.

Climate Change Is Accelerating Mercury Release

According to the researchers, glacier retreat and increased soil erosion are the primary drivers behind the growing release of mercury. The study estimates that mercury mobilization linked to melting ice and erosion has increased by approximately 550% since the Industrial Revolution.

Once mercury reaches the ocean, some of it becomes trapped in marine sediments. However, another portion is released back into the atmosphere through gas exchange between seawater and the air. Scientists estimate that these atmospheric emissions have also risen significantly over the past two centuries, allowing mercury to spread far beyond Antarctica.

This process creates a continuous environmental cycle that may keep mercury circulating for decades.

A Growing Threat to Marine Wildlife

Mercury is considered one of the world’s most dangerous pollutants because it can be transformed into methylmercury, a highly toxic compound that accumulates in living organisms.

Fish, shellfish, seabirds, seals, and whales can all absorb methylmercury through the food chain. As larger predators consume contaminated prey, mercury concentrations increase through a process known as bioaccumulation, posing serious risks to marine biodiversity.

Researchers warn that if global warming continues, the release of mercury from Antarctic ice could intensify, exposing polar ecosystems to even greater levels of contamination.

A New Challenge for Environmental Policy

The study’s authors argue that glacier melt should be recognized as an important factor in international pollution management strategies. While existing policies focus mainly on reducing current mercury emissions, the findings highlight another challenge: climate change is also releasing large quantities of historic pollution that has remained locked away for centuries.

Protecting glaciers is therefore essential not only to slow sea-level rise but also to prevent vast reserves of toxic substances from re-entering the atmosphere and oceans.

The research underscores that the consequences of climate change extend far beyond rising temperatures. The release of contaminants stored beneath polar ice represents an additional threat to biodiversity and reinforces the urgent need to reduce greenhouse gas emissions while protecting the world’s frozen regions.