Last year, the Arctic literally burned. Dried up by low rainfall and high temperatures, lightning strikes or an unattended camp fire were enough to set huge areas of taiga and tundra on fire and turn them into ash. Throughout the summer, millions of square kilometers were on fire throughout the Arctic. Then the fires disappeared, only to re-ignite this spring. Scientists and NASA discovered that the fires had not gone out last year, but had “continued to live” in the dry tundra soil.
The media, who were grateful for anything but the usual Corona news, dramatically called the resurgent fires “zombie” fires. Because in the dried-up soils of the tundra, which are often made of peat, last year’s fires could continue to smoulder and rise again at the first moment. This was also confirmed by experts such as Dr Mark Parrington, a scientist at the EU’s Copernicus Atmospheric Monitoring Service (CAMS). “We know from the climate data provided by C3S that the Arctic Circle regions most affected by fires in 2019 were experiencing warmer and drier surface conditions, providing the ideal environment for fires to burn and persist,” he said in a press release in May.
The impact of the fires was enormous, according to scientists. In particular, the amounts of carbon dioxide that additionally entered the atmosphere and the amounts of “black carbon”, i.e. soot, which have been drifted with winds, were calculated in the megaton range. For the period between January and August 2020 alone, an additional 244 megatonnes of CO2 entering into the atmosphere is estimated. These additional quantities, which set new records last year but were one-third below the 2020 level, are accelerating global warming further. And the soots carried by the winds onto the snow and ice surfaces of the Arctic can melt them faster because of amplification of the radiation.
The question now is whether these recurring fires are the new reality and the new normal, or whether this is an extreme event, fueled by the actual rising temperatures in the Arctic. CAMS scientists believe climate change was not the direct cause of the fires, as the BBC reports.
“These wildfires shed light on the domino effects of coinciding, multiple, interdependent natural hazards within the Arctic Circle, particularly extreme drought and persistent heat waves.”
Masoud Irannezhad et al (2020) Science 369 (6508)
A group of researchers from China, the US and Sweden in an article in the journal Sciencealso write that more data needs to be collected to more accurately determine the reasons and impacts of these fires. At present, only two years of data are available. “We lack sufficient data about the location and size of roasting areas, the amount of atmospheric heat-trapping greenhouse gas (CO2 and CH4 methane) emissions, the paths of the smoke plumes, and the sites of fire-related black carbon deposition,” the authors write. Nevertheless, they also warn that the growing regularity of such fires in the Arctic is due to the climatic changes to which regions beyond the Arctic Circle are exposed. “These wildfires shed light on the domino effects of coinciding, multiple, interdependent natural hazards within the Arctic Circle, particularly extreme drought and persistent heat waves.” These “zombies” are therefore not the staggering fantasy figures from movies and television, but a real danger that have global consequences for man and nature and could actually return more frequently.
Dr Michael Wenger, PolarJournal
Link to article: Irannezhad et al (2020) Science 369 (6508) The dangers of Arctic zombie wildfires, DOI: 10.1126/science.abe1739
More on the subject:
