Satellite images show the blazes that, over the past few weeks, have been burning through the Arctic Circle and the boreal forest, with serious consequences for habitats and the climate.
Arctic Circle forests had not been burning at this rate for at least 10,000 years. The abnormally high temperatures recorded in the Arctic over the past few weeks triggered, between June and July, the outbreak of numerous severe wildfires that are destroying forests and peatlands, causing an ecological catastrophe and contributing to the release of enormous quantities of CO2 into the atmosphere. The vast scale of the blazes is borne out by satellite images published by Pierre Markuse, a German expert in satellite photography.
Images captured by the Sentinel satellite show the blazes that have broken out in Greenland, Siberia, Alaska and Canada, with large plumes of smoke rising from the tundra across vast stretches of uninhabited, wild land.
As well as severely damaging Arctic ecosystems and the fauna and flora that inhabit them, the fires are causing the emission of large amounts of CO2, further exacerbating the global climate crisis. The blazes that broke out between 1 June and 21 July, according to Mark Parrington, a scientist at the Copernicus atmosphere monitoring service (Cams), have caused the release of approximately one hundred million tonnes of CO2 — a quantity roughly equivalent to Belgium's total emissions in 2017.
In this short space of time, scientists report, the entire quantity of carbon dioxide emitted between 2010 and 2018 by all Arctic wildfires combined has been released into the atmosphere. "I think it's fair to say that the fires that affected the Arctic Circle in July have reached unprecedented levels," Parrington tweeted. "Since the beginning of June, Cams has been monitoring more than one hundred intense, long-lasting fires in the Arctic Circle," reads a statement from the World Meteorological Organization (WMO). "The northern part of the world is warming faster than the rest of the planet, and this heat is drying out forests, making them more vulnerable to fire."
Despite the flames having broken out across the wild, uninhabited expanses of the Arctic, people too are threatened by their effects. "Wildfires emit several types of pollutants," Cams warned, "many of which can affect our health. Wind can carry pollution thousands of kilometres from its source, affecting air quality around the world."
The blazes in Alaska, fuelled by extraordinarily high temperatures, are still out of control and are incinerating large areas of forest. The nearly 260 fires — most of them ignited by lightning — have burned approximately 900,000 hectares of land, particularly in the north of the state. "It is unusual to see fires of such scale and duration at these latitudes in June," Parrington said. The flames have also reached the Kenai Peninsula, located on Alaska's southern coast. The fire does not appear to be spreading and is being monitored by firefighters to ensure it does not threaten power lines and other infrastructure.
The extent and duration of the fires suggest that it is not only forests that are burning, but also peatlands — the planet's largest natural carbon stores. These are environments where peat forms and accumulates: a fossil fuel derived from the partial carbonisation of plant debris and deposits in water. Under natural conditions, peat, which is composed predominantly of water, is capable of preventing the spread of forest fires. But humans have plundered peatlands for their own purposes by draining them, and few things in nature are as flammable as dry peat. Peatland fires, unlike forest fires which burn out within a few days at most, can burn continuously for weeks and even months. Fires burning through peatlands also cause the release of large quantities of CO2. Extinguishing the fires devastating large swathes of the Arctic is virtually impossible, as they broke out in remote and inaccessible areas. The only hope lies in rain.
The fires are also accelerating the thawing of permafrost — the vast layer of ice covering much of the Arctic, which is already under strain from global warming. The melting of the permafrost would have catastrophic consequences: trapped within it are billions of tonnes of greenhouse gases. According to a study published last April in Nature, nearly 1,600 billion tonnes of carbon are stored in the frozen soils of the northern hemisphere — twice the amount contained in the atmosphere. It is also likely that ancient viruses are concealed within the Arctic ice, which could once again pose a threat to humans and animals.
