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The Copernicus Atmosphere Monitoring Service has been closely monitoring a summer of extreme wildfires across the Northern Hemisphere, including intense hotspots around the Mediterranean basin and in North America and Siberia. The intense fires led to new records in the CAMS dataset with the months of July and August seeing their highest global carbon emissions respectively.

Scientists from the Copernicus Atmosphere Monitoring Service (CAMS) have been closely monitoring a summer of severe wildfires which have impacted many different countries across the Northern Hemisphere and caused record carbon emissions in July and August. CAMS, which is implemented by the European Centre for Medium-Range Weather Forecasts on behalf of the European Commission with funding from the EU, reports that not only large parts of the Northern Hemisphere were affected during this year’s boreal fire season, but the number of fires, their persistence and intensity were remarkable.

As the boreal fire season draws to a close, CAMS scientists reveal that:

• Dry conditions and heatwaves in the Mediterranean contributed to a wildfire hotspot with many intense and fast developing fires across the region, which created large amounts of smoke pollution.
• July was a record month globally in the GFAS dataset with 1258.8 megatonnes of CO₂ released. More than half of the carbon dioxide was attributed to fires in North America and Siberia.
• According to GFAS data, August was a record month for fires as well, releasing an estimated 1384.6 megatonnes of CO₂ globally into the atmosphere.
• Arctic wildfires released 66 megatonnes of CO₂ between June and August 2021.
• Estimated CO₂ emissions from wildfires in Russia as a whole from June to August amounted to 970 megatonnes, with the Sakha Republic and Chukotka accounting for 806 megatonnes.

Scientists at CAMS use satellite observations of active fires in near-real-time to estimate emissions and predict the impact of resulting air pollution. These observations provide a measure of the heat output of fires known as fire radiative power (FRP), which is related to the emission. CAMS estimates daily global fire emissions with its Global Fire Assimilation System (GFAS) using the FRP observations from the NASA MODIS satellite instruments. The estimated emissions of different atmospheric pollutants are used as a surface boundary condition in the CAMS forecast system, based on the ECMWF weather forecast system, which models the transport and chemistry of atmospheric pollutants, to predict how global air quality will be affected up to five days ahead.

The boreal fire season typically lasts from May to October with peak activity taking place between July and August. In this summer of wildfires, the most affected regions were:

Mediterranean

Many nations in eastern and central Mediterranean suffered the effects of intense wildfires throughout July and August with smoke plumes clearly visible in satellite imagery and CAMS analyses and forecasts crossing the eastern Mediterranean basin. As southeast Europe experienced prolonged heatwave conditions, CAMS data showed daily fire intensity for Turkey reaching the highest levels in the GFAS dataset dating back to 2003. Following the fires in Turkey, other countries in the region went on to be affected by devastating wildfires including Greece, Italy, Albania, North Macedonia, Algeria, and Tunisia.

Fires also hit the Iberian Peninsula in August, affecting vast parts of Spain and Portugal, especially a large area near Navalacruz in the Avila province, just west of Madrid. Extensive wildfires were also registered east of Algiers in northern Algeria, CAMS GFAS forecasts showing high surface concentrations of the polluting fine particulate matter PM2.5 (compare cover picture).

GEFF fire danger forecasts initialized on 31 July 2021, showing 'very extreme' (purple shading) around the Mediterranean valid for 7 August. Credit: EFFIS

Siberia

While the Sakha Republic in northeastern Siberia typically experiences some degree of wildfire activity every summer, 2021 has been unusual, not just in size but also the persistence of high-intensity blazes since the beginning of June. A new emissions record was set on 3^rd August for the region and emissions were also more than double the previous June to August total. In addition, the daily intensity of the fires reached above average levels since June and only began to subside in early September. Other areas affected in Siberia have been the Chukotka Autonomous Oblast (including parts of the Arctic Circle) and the Irkutsk Oblast. The increased activity observed by CAMS scientists corresponds with increased temperatures and decreased soil moisture in the region.

Left: Estimated carbon emissions for the period June-July-August and the years 2003-2021 for Sakha Republic. Right: Daily Fire Radiative Power, a measure for heat output, for fires in the Sakha Republic 2021. Credit: Copernicus Atmosphere Monitoring Service/ECMWF

North America

Large scale wildfires have been burning in western regions of North America throughout July and August affecting several Canadian provinces as well as the Pacific Northwest and California. The so-called Dixie Fire which raged across northern California is now one of the biggest ever recorded in the state’s history. Resulting pollution from the persistent and intense fire activity affected the air quality for thousands of people in the region. CAMS global forecasts also showed a mixture of smoke from the long-running wildfires burning in Siberia and North America travelling across the Atlantic. A clear plume of smoke was seen moving across the north Atlantic and reaching western parts of the British Isles in late August before crossing the rest of Europe. This happened as Saharan dust was travelling in the opposite direction across the Atlantic including a section over southerly areas of the Mediterranean resulting in reduced air quality.

Left: Estimated carbon emissions for the period June-July-August for Western USA in the years 2003-2021. Right: Daily total Fire Radiative Power for Western USA in 2021. Credit: Copernicus Atmosphere Monitoring Service/ECMWF

Mark Parrington, Senior Scientist and wildfire expert at the ECMWF Copernicus Atmosphere Monitoring Service, comments: “Throughout the summer we have been monitoring wildfire activity across the Northern Hemisphere. What stood out as unusual were the number of fires, the size of the areas in which they were burning, their intensity and also their persistence. For example, the wildfires in Sakha Republic in northeastern Siberia have been burning since June and only started receding in late August although we have been observing some continuing fires in early September. It’s a similar story in North America, parts of Canada, the Pacific Northwest and California, which have been experiencing large wildfires since the end of June and beginning of July and are still ongoing.”

“It is concerning that drier and hotter regional conditions - brought about by global warming - increase the flammability and fire risk of vegetation. This has led to very intense and fast-developing fires. While the local weather conditions play a role in the actual fire behaviour, climate change is helping provide the ideal environments for wildfires. More fires around the world are anticipated in the coming weeks, too, as the fire season in the Amazon and South America continues to develop.” he adds.

More information on wildfires in the Northern Hemisphere during summer 2021: https://atmosphere.copernicus.eu/northern-hemisphere-wildfires-follow-pattern-warm-and-dry-weather

The CAMS Global Fire Monitoring page can be accessed here: https://atmosphere.copernicus.eu/fire-monitoring

Find out more about fire monitoring in the CAMS Wildfire Q&As: https://atmosphere.copernicus.eu/qa-wildfires