Humans blamed for spike in homes and buildings destroyed by wildfires

"Human fingerprints are all over this — we influence the when, the where, and the why," lead author Philip Higuera, a fire ecologist and professor at the University of Montana, said.

In Ireland, gorse fires have become a major issue in recent years. in April 2021, the whole of Killarney National Park was threatened after a fire, started within, blazed out of control. 

In Cork last April, the Glen River Park on the northside of the city was besieged by two fires within 48 hours, believed to have been the result of arson. Last August, a massive wildfire on Mount Leinster could be seen from Carlow, Wexford, and Kilkenny, taking dozens of firefighters to bring it under control.

Prof Higuera worked with several researchers at the Cooperative Institute for Research in Environmental Sciences (CIRES) to examine 15,000 Western wildfires between 1999 and 2020.

It found that wildfires are extending to previously out-of-season months, while more buildings are in areas of vegetation prone to blazes. Burned area increased 30% across the West but structure loss rose by nearly 250%, the team found.

In addition, nearly two-thirds of all structures destroyed since the turn of the century were lost in just three years — 2017, 2018, and 2020.

Between 1999 and 2009, just over one structure was lost for every 1,000 hectares of land scorched by wildfire. Between 2010 and 2020, that ratio increased to more than three.

The likes of backyard burning, power lines, and other human-related ignition accounted for 76% of all structure loss and resulted in 10 times more structures destroyed per unit area burned compared to lightning-ignited fires, the analysis found.

The findings come just months after Europe experienced one of its worst environmental and human catastrophes in years as several countries were beset by wildfires.

A report from Christian Aid calculated that drought caused by the extreme heat across Europe during the summer was likely to have cost €20bn and 20,000 deaths in excess of normal, with wildfires and agricultural losses particularly acute.

Wildfires across Europe proved costly not just in monetary terms, but also regarding emissions. Emissions from June to August were the highest summer total wildfire output estimated for the EU plus Britain in the last 15 years. 

France, Spain, Germany, and Slovenia experienced their highest summer wildfire emissions for at least the last 20 years, Copernicus said. Australia suffered one of its worst climate disasters in 2019-2020, with 19m hectares burned and 3,000 homes destroyed.

Climate change mitigation is essential, the American scientists said.

"Longer fire seasons—a result of climate change— mean that human-related ignitions are more consequential, leading to more destructive wildfires in the fall and early winter, for example, when they were once rare," they said.