1. 2003 Siberian Taiga Fires (Russia) – 55 Million Acres

In 2003 – during one of the hottest summers Europe experienced up to that point – a series of extremely devastating blazes in the taiga forests of Eastern Siberia destroyed over 55 million acres (22 million hectares) of land.

A combination of extremely arid conditions and increased human exploitation during recent decades are believed to have played a role in what is remembered as one of the most devastating and largest wildfires in human history. The fires spread across Siberia and the Russian Far East, northern China, and northern Mongolia, sending a plume of smoke that reached Kyoto thousands of miles away. Emissions from the Siberian Taiga fires can be compared to the emission cuts promised by the European Union under the Kyoto Protocol and their effects can still be seen in present-day environmental studies on ozone depletion.

2. 1919/2020 Australian Bushfires (Australia) – 42 Million Acres

The 2020 Australian bushfires went down in history for their catastrophic impact on wildlife. The ​​extreme bushfires tore through New South Wales and Queensland in southeastern Australia, burning 42 million acres, destroying thousands of buildings, and killing dozens of people as well as 3 billion animals, including a staggering 61,000 koalas. Australia experienced the hottest and driest year in its recorded history in late 2019 and early 2020, which was a major contributing factor to the devastating wildfires. Data released by the climate monitoring body show Australia’s mean temperature in 2019 was 1.52°C higher than average, making it the warmest year since records began in 1910; January 2019 was the warmest month Australia has ever recorded. Rainfall was 40% below average, its lowest level since 1900.

3. 2014 Northwest Territories Fires (Canada) – 8.5 Million Acres

In the summer of 2014, over 150 separate fires broke out across the Northwest Territories, an area of about 442 square miles (1.1 billion square kilometres) in northern Canada. 13 of them were believed to have been caused by humans. The smokes they generated sparked air quality warnings across the whole country as well as in the US, with smoke visible as far away as Portugal in western Europe. A total of nearly 8.5 million acres (3.5 million hectares) of forest were completely destroyed and firefighters operations cost the government a staggering US$44.4 million. These devastating consequences made the Northwest Territories Fires one of the worst recorded in nearly three decades.

 4. 2004 Alaska Fire Season (US) – 6.6 Million Acres

 2004 year fire season in Alaska State was the worst on record  in the history of the US state of Alaska in terms of area burned. More than 6.6 million acres (2.6 million hectares) of land were burned by 701 fires. 215 of these were started by lightning strikes; the other 426 were started by humans. The summer of 2004 was extremely warm and wet in comparison to the typical interior Alaska summer climate, which resulted in record amounts of lighting strikes. After months of this lighting and increased temperatures, an uncharacteristically dry August resulted in the fires that continued through September.

 5. 1939 Black Friday Bushfire (Australia) – 5 Million Acres

 Gone down in history as Black Friday, the bushfires that destroyed more than 5 million acres in Victoria – a state in southeastern Australia – in 1939, were the culmination of several years drought, followed by high temperatures and strong winds. The fires covered over three-quarters of the state’s area and resulted in 71 casualties, making it the third most deadly bushfire in Australia’s history. Despite going on for several days, on 13 January, when temperatures reached 44.7C in the capital Melbourne and 47.2C in Mildura in the northwest, the fires escalated, claiming 36 lives and destroying more than 700 homes, 69 sawmills as well as several farms and businesses. Ash from the blazes fell as far away as New Zealand.

6. The Great Fire Of 1919 (Canada) – 5 Million Acres

 Despite happening more than a century ago, the Great fire of 1919 is still remembered as one of the largest and most devastating wildfires in history. In early May, a complex of many fires swept through the boreal forest of the Canadian provinces of Alberta and Saskatchewan. The wood that had been cut for the timber industry, combined with strong, dry winds, contributed to the quick-burning flames that, within just a few days, ravaged about 5 million acres (2 million hectares), destroying hundreds of buildings and claiming 11 lives.

7. 1950 Chinchaga Fire (Canada) – 4.2 Million Acres

Also known as the Wisp fire and ‘Fire 19’, the Chinchaga Forest Fire burned in Northern British Columbia and Alberta from June until the early fall of 1950. It went down in history as one of the largest recorded fires in North American history, burning an area of approximately 4.2 million acres (1.7 million hectares). While lowering the impact on buildings and threat to humans, the lack of settlements in the region allowed the fire to burn freely. The massive amount of smoke from the blazes created the historic  Great Smoke pall, a thick cloud of smoke that obscured the sun for nearly a week, turning it blue and making it visible to the naked eye without discomfort. The phenomenon could be observed for several days across eastern North America and Europe.

 8. 2010 Bolivia Forest Fires (South America) – 3.7 Million Acres

 In August 2010, more than 25,000 fires burned across Bolivia, covering an area of approximately 3.7 million acres (1.5 million hectares) and damaging especially the country’s section of the Amazon. The thick smoke that resulted from them forced the government to halt numerous flights and declare a state of emergency. Among the causes was a combination of fires started by farmers to clear land for planting as well as dry vegetation resulting from the extreme drought that the country experienced during the summer months. The Bolivia forest fires were some of the worst the South American nation experienced in nearly 30 years.

 9. 1910 Great Fire of Connecticut (US) – 3 Million Acres

 Also called the Big Burn, Big Blowup or the Devil’s Broom fire, this wildfire roared through the states of Idaho and Montana during the summer months of 1910. Despite burning for just two days, strong winds caused the initial fire to combine with other smaller fires to form one massive blaze that destroyed 3 million acres (1.2 million hectares) – approximately the size of the entire state of Connecticut – and killed 85 people, making this one of the worst wildfires in US history. Despite being remembered for the destruction it caused, the Fire paved the way for the government to enact forest protection policies. 

10. 1987 Black Dragon Fire (China and Russia) – 2.5 Million Acres

Also known as the Daxing’annling Wildfire, the Black Dragon fire of 1987 may have been the largest single fire in the world in the past several hundred years as well as the deadliest forest fire in the People’s Republic of China. It burned incessantly for over a month, destroying approximately 2.5 million acres (1 million hectares) of land, 18 million acres of which were forest. While the exact cause is not clear, Chinese reports stated that the fire might have been caused by human action. A total of 191 lives were lost during the fire, with a further 250 left injured. Additionally, nearly 33,000 people were left displaced.