Now, it appears there is another thing we should worry about – the nuclear fallout buried in all that snow and ice. Radioactive icebergs sound like a dodgy plot device in a fanciful disaster flick along the lines of Geostorm. And yet, emerging research presented at this year's General Assembly of the European Geosciences Union (EGU) suggests that radioactive debris stored in glaciers really could be a ticking time bomb.
"Research into the impact of nuclear accidents has previously focussed on their effects on human and ecosystem health in non-glaciated areas," lead researcher Caroline Clason, from the University of Plymouth, said in a statement.
"But evidence is mounting that cryoconite on glaciers can efficiently accumulate radionuclides to potentially hazardous levels."
This is the first time an international team of researchers has set about analyzing the nuclear contents of glaciers in the Arctic, the Antarctic, the Alps and Caucasus Mountains, British Columbia, and Iceland. Their findings reveal levels of human-made radioactive material in each of the 17 sites surveyed. Frequently, these were at concentrations 10 times higher (or more) than those at non-glacial sites.
The explanation for this especially high concentration comes down to the dispersal of radioactive particles after a nuclear disaster event like Chernobyl or Fukushima. These particles are light and can travel far.
Normally, they return to the ground as acid rain, where they may be absorbed into the soil or consumed by plants. Hence, the higher concentrations of radioactivity in places like Chernobyl and Fukushima – and, subsequently, higher cancer rates, higher infertility rates, and the existence of radioactive boar. However, some of these particles will travel to icier climes where they fall to Earth as snow, land on the ice, set in weightier sediment, and accumulate in denser concentrations.
The team analyzed the material and not only did they find nuclear fallout from Chernobyl and Fukushima, both nuclear accidents, but they also found material from decades of nuclear weapons testing.
"We're talking about weapons testing from the 1950s and 1960s onwards, going right back in the development of the bomb," Clason told the Associated Press.
"If we take a sediment core you can see a clear spike where Chernobyl was, but you can also see quite a defined spike in around 1963 when there was a period of quite heavy weapons testing."
While research shows that radioactive material in the food chain is definitely not good for you, it is unclear yet what the presence of this nuclear fallout means exactly. The team hopes to find out.
"Very high concentrations of radionuclides have been found in several recent field studies, but their precise impact is yet to be established," Clason said.
"Our collaborative work is beginning to address this because it is clearly important for the pro-glacial environment and downstream communities to understand any unseen threats they might face in the future."