How high-latitude peat and forest fires could shape the future of Earth’s climate

Understanding how forest fires influence the climate of our planet is an intimidating challenge. Although fire occurs almost everywhere on earth and has always been present, it is always one of the least understood components of the earthly system. Recently, an unprecedented shooting activity has been observed in the boreal (north) and Arctic regions, which attracted the attention of the scientific community to the fields whose role in the future of our planet remains a mystery. Climate change probably has a major role in this alarming trend. However, high latitude forest fires are not only a symptom of climate change; They are an acceleration force that could shape the future of our climate in a way that we are currently unable to predict.

The growing threat of northern fires

As global temperatures increase, forest fires are growing further north and reaching the Arctic. Canada, Alaska, Siberia, Scandinavia and even Greenland, all in the northern latitude regions, have recently experienced some of the most intense and prolonged forest seasons. With climate change occurring more quickly in these regions, the future of fires in the North seems even darker.

In addition to typical forest fires that consume surface vegetation, many high latitude fires burn by peat, the dense layers rich in organic matter partially in decomposition. Although they cover only 3% of the earth’s surface, peat bogs are one of the most important carbon storage environments in the world, containing around 25% of the existing carbon in earth soils.

Global warming, which is even faster at high latitudes in northern due to polar amplification – the greatest climate change phenomenon near the poles compared to the rest of the hemisphere or the globe – increases the vulnerability of these fire ecosystems, with potentially serious implications for the global climate. When the peat bogs light up, they release massive quantities of “fossil carbon” which have been locked up for centuries or even millennia. The most important and most persistent fires on earth, peat fires can smoke for long periods, are difficult to put out and can continue to burn underground throughout the winter, only to revive on the surface in the spring. They have recently been described as “zombies” fires.

Warm and darkest conditions led by climate change, in addition to making boreal forests more flammable, should intensify and increase the frequency of peat fires, potentially transforming the peat bogs of carbohydrates into net sources of greenhouse gas emissions. Such a change could trigger a feedback loop, which means that a warming climate will cause more carbon emissions, which will accelerate climate change.

Air pollution and weather conditions

Forest fires release large quantities of smoke particles (aerosols) in the atmosphere, contributing significantly to the local and widespread degradation of air quality. These particles are harmful to human health and can cause serious respiratory and cardiovascular problems, while prolonged exposure can cause stress induced by smoke, hospitalizations and increased mortality. Forest fires can also cause mental health strains associated with evacuations, loss of houses, livelihoods and lives.

Beyond their long-term climate effects, forest emissions can also influence weather conditions more in the short term via their impacts on air pollution levels. Smoke particles interact with sunlight and cloud formation processes, affecting temperatures, wind models and precipitation.

For example, our recent study on large -scale atmospheric impacts of Canadian forest fires in 2023, which we presented to the General Assembly of the Union of European Geosciences this spring, demonstrated that the aerosols of forest fires led to a reduction in the temperature of the surface air which has spread to the whole northern hemisphere. The cooling was particularly pronounced in Canada (up to -5.5 ° C in August), where the emissions were located, but were also significant in remote areas such as Eastern Europe and even Siberia (up to approximately -2.5 ° C in July). The average hemispherical temperature anomaly that we have calculated (almost -1 ° C) highlights the potential of large regional emissions, forest fires to disrupt weather conditions for weeks in a whole hemisphere, with deep implications for forecasting. Unreliable weather forecasts can disrupt daily activities and present risks to public security, especially during extreme events such as heat waves or storms. They also have serious consequences for industries such as agriculture, fishing and transport, where planning strongly depends on precise and timely predictions.

Peat fires and climate puzzle

Although the integration of peat bog feeds into the models of terrestrial systems (ESMS) is essential for precise climatic projections, most existing models have no representation of peat fires. Understanding the smoking behavior of organic soils when burning, their probability of ignition and how these processes can be represented on a global scale is of the utmost importance. Recent research efforts are focused on filling this lack of knowledge. For example, at the Technical University of Crete, we collaborate with the Hazelab Research Group of the Imperial College London and the Leverhulme Center for Wild Fire, Environment and Society to carry out research on the ground and advanced experiences) on the peat smoke, in order to highlight the complex mechanisms of peat fires.

The integration of these laboratory results into ESMs will allow a model emissions that changes the game, which presents a potential for revolutionary results with regard to our level of competence to predict the future of the earth climate. By quantifying how the current atmosphere is influenced by fire emissions from boreal forests and peat bogs, we can improve the quality of projections of world temperature elevation. This integration has also referred to forecasts of regional climatic impacts driven by fire -related aerosols, such as changes in precipitation patterns or the melting of accelerated arctic ice.

Take up the challenge of northern fires

Without a doubt, we have entered an era of more frequent megafires – fires of size, intensity, duration or extreme impacts – with catastrophic consequences. The recent megafire events in the boreal and arctic regions reveal the dramatic change of forest models in high latitudes of the North, which is a question that requires urgent attention and action.

While the planet continues to warm up, high latitude fires should help shape the future of our planet. Massive forest fire events, such as those in Canada in 2023, have not only burned millions of hectares, but also forced hundreds of thousands of people to evacuate their homes. Unprecedented quantities of parts covered by the smoke of North America in dangerous air, causing school closures and health warnings and forcing citizens to stay inside for days. Events like this reflect an increasing trend. They emphasize why the progress of research to better understand and predict the dynamics of northern peat tours and forest fires, and to alleviate their climatic impacts, is not only a scientific imperative but also moral responsibility.

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