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Newsflash Reading 27/05/2020

As the Boreal fire season is beginning to get underway in the northern hemisphere, scientists from the Copernicus Atmosphere Monitoring Service (CAMS) are keeping a watchful eye on activity in the Arctic Circle as satellites are starting to detect active fires. CAMS and other scientists are considering the possibility of existing ‘Zombie’ fires in the Arctic, although this hypothesis has not been confirmed at the moment, given the absence of ground measurements. CAMS, implemented by the European Centre for Medium-Range Weather Forecasts (ECMWF) on behalf of the European Commission, consistently monitors the intensity and emissions from fires across the world.

Following last year’s unprecedented fires in some areas of the northern hemisphere, CAMS scientists have taken a first look at Arctic Circle wildfires for 2020 with data from the Global Fire Assimilation System (GFAS), which uses observations from satellite-based sensors to provide daily estimates of emissions and information about the fires’ intensity which are then compared with the average of previous years to build up a longer-term picture. They have observed ‘fairly typical’ fire activity for the region, which is expected to increase in the next few weeks as the season progresses, according to estimates from 2003-2019 climatology.

The Fire Radiative Power – a measure of heat output from wildfires in the Arctic Circle shown as the boreal fire season gets underway (red) and the 2003–2019 average (grey). Credit: Copernicus Atmosphere Monitoring Service (CAMS), ECMWF

The risk of wildfires can be aggravated by unusually warm and dry conditions and there have already been record temperatures in Europe for March and April this year. ECMWF Copernicus’s sister service, the Copernicus Climate Change Service (C3S), reported that April 2020 temperatures were above average in northern and coastal central Greenland as well as much of Siberia.

“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,” explains Mark Parrington, CAMS Senior Scientist and wildfire expert.

Signals that ‘Zombie’ fires might have reignited in the Arctic Circle are cause for concern as last year’s wildfires in the region were unprecedented, emitting an estimated 50 megatonnes of carbon dioxide in June 2019 alone– the equivalent of Sweden’s total annual emissions.

Mark Parrington explains: “We have seen satellite observations of active fires that hint that ‘Zombie’ fires might have reignited, yet it has not been confirmed by ground measurements. The anomalies are quite widespread in areas that were burning last summer. If this is the case, then under certain environmental conditions, we may see a cumulative effect of last year’s fire season in the Arctic which will feed into the upcoming season and could lead to large-scale and long-term fires across the same region once again.”

CAMS scientists have already been monitoring wildfire activity in other parts of the world during the northern hemisphere tropical fire season, which has recently come to an end. They can report that emissions for the Caribbean region including countries such as Belize, Guatemala, Honduras, Nicaragua, Panama and the Mexico Yucatan Peninsula, were well above the 2003-2019 average. Correspondingly, the intensity of the fires, known as the Fire Radiative Power (FRP), was as also found to be well above the 2003-2019 average in these countries.

The Fire Radiative Power – a measure of heat output from wildfires shown during the northern hemisphere tropical fire season (red) and the 2003–2019 average (grey). Credit: ECMWF Copernicus Atmosphere Monitoring Service (CAMS) 

By contrast, the emissions and intensity of fires in South East Asia including Cambodia, Laos, Malaysia and Myanmar were closer to average, with Thailand and Vietnam registering lower than average.

One particular region badly affected by wildfires was Indonesia, suffering one of the most intense incidents in almost 20 years. CAMS scientists estimated that the Indonesian fires that began in August 2019 and only ended three months later, pumped out at least 708 megatonnes of CO2. Drier than average conditions combined with the burning of carbon-rich peatlands were thought to be the main cause of the intensive flare-ups. The scientists of CAMS estimated that the daily total fire intensity was higher than the average of the last 16 years. The resulting toxic haze not only had a detrimental effect on the local population, but also caused lasting damage to the natural forests and wildlife.

Mark Parrington comments: “We have also been closely monitoring the emissions and intensity of fires in the tropical regions of the northern hemisphere, and while some regions were slightly above average, others were slightly reduced. This goes to show that although some areas are at more risk of greater wildfire activity in warmer/drier conditions, it is never an easy or straightforward picture. Our work involves monitoring these fires very closely for both emissions and intensity so that we can build up a longer-term representation over time to understand their impact on atmospheric composition and inform policymakers and organisations who are looking at mitigation measures.” 

You can find more information about the tropical fire season in the northern hemisphere here.