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Newsflash, Reading, 06/12/2021

Graphic: Still of animation of global fire activity on 31/07/2021 showing wildfires in Siberia, North America and around the Mediterranean. Credit: Copernicus Atmosphere Monitoring Service/ECMWF

Scientists in the Copernicus Atmosphere Monitoring Service have been keeping a close watch on wildfire emissions and their impacts on the atmosphere around the world throughout 2021. The service uses satellite observations of active fires to estimate wildfire emissions in near-real-time and predict the subsequent impact on air quality and the atmosphere.

Several regions around the world experienced a year of intense, prolonged, and devastating wildfires which caused an estimated total of 1760 megatonnes of carbon emissions, according to scientists from the Copernicus Atmosphere Monitoring Service (CAMS). The year also saw some of the highest estimatedemissions in several regions around the world based on the CAMS 19-year Global Fire Assimilation System (GFAS) dataset. Implemented by the European Centre for Medium-Range Weather Forecasts on behalf of the European Commission with funding from the European Union, CAMS closely monitors active fires worldwide providing estimated emissions and the impact on atmospheric composition and air quality.

In April, intense and persistent fire activity was observed in western Siberia and Canada. The pattern of activity observed by CAMS scientists coincided with high surface temperature anomalies in these regions.

Global carbon emissions of wildfires between 1 January and 30 November since 2003 according to CAMS GFAS data.

Global carbon emissions of wildfires between 1 January and 30 November since 2003 according to CAMS GFAS data. Credit: Copernicus Atmosphere Monitoring Service/ECMWF

The summer of 2021 in particular experienced a number of extreme wildfires which led to the highest estimated emissions for some of the months in the CAMS GFAS dataset. Not only were extensive parts affected throughout the summer, but their persistence and intensity were remarkable. This included vast expanses in North America, Siberia, eastern and central Mediterranean, and North Africa. Julys monthly total estimated emissions were shortly the highest for 2021 in the CAMS GFAS dataset with 343 megatonnes of carbonreleased into the atmosphere. More than half of the emissions were ascribed to fires in North America and Siberia, two of the worst affected regions. According to GFAS data, August followed suit with the monthly total estimated emissions being even higher with an estimated 378 megatonnes of carbon released into the atmosphere globally.

The 2021 year of wildfires featured four key regions: 

Siberia

A huge number of wildfires raged across areas of western Siberia around Omsk and Tyumen resulting in daily emissions at well above the mean of previous years in the dataset for 2003-2021. Meanwhile, eastern territories were not as active early in the season. The difference was clearly reflected in the surface temperature anomalies for the regions. In the summer however, wildfires in the Sakha Republic in northeastern Siberia set the highest summer-time total in the CAMS GFAS dataset from June to August at more than double previous years. Furthermore, daily fire intensity, measured as Fire Radiative Power (FRP), reached significantly above average levels from June right through to early September. Other regions in eastern Russia, including parts of the Arctic Circle, Chukotka Autonomous Oblast and Irkutsk Oblast, also experienced fires but much less than in 2020 and 2019.

Daily Cumulative wildfire carbon emissions from the CAMS Global Fire Assimilation System (GFAS). Credit: Copernicus Atmosphere Monitoring Service/ECMWF.

Daily Cumulative wildfire carbon emissions from the CAMS Global Fire Assimilation System (GFAS). Credit: Copernicus Atmosphere Monitoring Service/ECMWF.

North America

Wildfires burned across western parts of North America for a significant period from the end of June to late August. The worst affected areas included several provinces in Canada, as well as California and the states in the Pacific Northwest of the USA. Among the fires was also the second* largest recorded fire in Californian state history, dubbed the Dixie Fire after the road in which it started. In all, the fires released estimated total carbon emissions of approximately 83 megatonnes into the atmosphere. The high intensity and persistence of the wildfire emissions could be seen in CAMS global forecasts as a large plume of smoke crossed the North Atlantic and, mixing with wildfires from Siberia, reached western parts of the British Isles and northwest Europe in late August before travelling across large parts of Europe.

CAMS carbon monoxide mixing ratio at 500 hPa (approx. 5km) forecast valid for 12 UTC on 19th August showing smoke transport from North American fires across the Atlantic. Credit: Copernicus Atmosphere Monitoring Service/ECMWF

CAMS carbon monoxide mixing ratio at 500 hPa (approx. 5km) forecast valid for 12 UTC on 19^th August showing smoke transport from North American fires across the Atlantic. Credit: Copernicus Atmosphere Monitoring Service/ECMWF

The Mediterranean

Many countries around the eastern and central Mediterranean suffered several days of high intensity wildfires in July and August, leading to high concentrations of fine particulate matter (known as PM2.5) and degraded air quality. The particularly dry and hot conditions throughout the summer months provided the ideal environment for intense and long-lasting wildfires. Turkey was the worst hit in July with CAMS GFAS data showing daily fire intensity at very high levels which were well above average for the region. Other countries also affected by the devastating wildfires included Greece, Italy, Albania, North Macedonia, Spain, Algeria and Tunisia.

Left: CAMS Daily Total Fire Radiative Power for Turkey (left) compared to the 2003-2020 mean (grey). Right: GEFF fire danger forecast across southeast Europe for 30 July 2021. Credit: Copernicus Emergency Management Service; Copernicus Atmosphere Monitoring Service/ECMWF 

North India

Seasonal crop stubble burning in Pakistan and north-western India occurs every year between late September and the end of November. The haze and smoke pollution caused by this activity was clearly apparent in visible satellite imagery during October and November 2021 and has also been reflected in very high values of fine particulate matter and aerosol optical depth in the CAMS global forecasts throughout the region. Significant air pollution was observed, and reported, throughout the Indo-Gangetic Plain (IGP), affecting millions of people. The majority of the fires were in the Indian states of Punjab and Haryana.

CAMS analyses of aerosol optical depth and surface PM2.5 concentration over South Asia between 1 and 28 November 2021. Credit: Copernicus Atmosphere Monitoring Service/ECMWF

Mark Parrington, Senior Scientist and wildfire expert at the ECMWF Copernicus Atmosphere Monitoring Service, comments: “As the year draws to a close, we have seen extensive regions experience intense and prolonged wildfire activity, some of which has been at an level not observed in the last couple of decades. Drier and hotter regional conditions caused by global warming increase the risk of flammability and fire risk of vegetation and this has been reflected in the extremely large, fast-developing and persistent fires we have been monitoring.”

“It is clear from 2021 that climate change is providing the ideal environments for wildfires, which can also be exacerbated by local weather conditions. Our five-day forecasts allow decision-makers, organisations and individuals to take mitigating action in advance of any pollution incidents,” he adds.

More information on wildfires in the Northern Hemisphere during 2021 can be found here: https://atmosphere.copernicus.eu/wildfires-wreaked-havoc-2021-cams-tracked-their-impact-nf

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