This is part of a series on the effects of climate change.
How do wildfires start?
The two most common causes for wildfires are lightning strikes and human activity, although determining the origin is not always possible. Wildfires have been documented throughout human history and usually start when weather conditions are particularly dry and hot. Areas that offer dense vegetation are more susceptible to such outbreaks, which is why indigenous people introduced controlled burns to reduce the dangers of larger uncontrollable fires. In the past decade, on average, more than five million hectares of tree cover were lost per year due to wildfires worldwide.Most affected regions
The United States is among the countries most affected by wildfires. In the past decade, between three and 10 million acres of land were burned every year. Most of these wildfires occur in the West, a region that receives minimal rainfall in the hot summer months and is home to easily flammable pine forests and shrublands. California has been hit by some of the most destructive wildfires in recent history, and its annual fire season has begun to stretch longer each year as Californian lands have become drier.The Amazon rainforest, which stretches across northwestern Brazil and parts of its neighboring countries, has become increasingly threatened by acts of deforestation and naturally occurring wildfires. In 2022, over 145,000 wildfire outbreaks were recorded in the Legal Amazon area in Brazil, accounting for nearly three-quarters of all wildfires in the country that year. Canada, Russia, Australia, Spain, Greece, and Indonesia are also among the countries ravaged by large wildfires in recent years.