The science of attribution , in which the study falls, is an emerging field.
Carbon emissions from fossil fuel companies are impacting the area burned by wildfires in western Canada and the United States, a new study says.
As this fire season could turn out to be the worst in Alberta's history, a new study finds a measurable link between the carbon emissions of major producers of fossil fuels and the increase in the number of blazes in Canada and the United States.
The study, peer-reviewed and published in the scientific journal Environmental Research Letters, concludes that the world's 88 largest fossil fuel and cement companies are responsible for 37% of the forest area burned in Western Canada and the Western United States between 1986 and 2021.
That's about 80,000 square kilometers more than what would have been consumed without emissions from these industries, according to the study, an area greater to that of Ireland.
Without the emissions from the 88 companies, the fires would have burned a cumulative area of 134,735 square kilometers, the researchers write, compared to the 214,000 square kilometers observed.
We have shown that emissions from these companies have dramatically increased the severity of wildfires, says Carly Phillips, co-author of the study and researcher at the Union of Concerned Scientists, an American organization that brings together, among other , scientists who study environmental issues.
To reach this conclusion, the researchers modeled the impact of the global mean temperature (GMT) on the vapor pressure deficit (DPV), which measures the difference between the level of water vapor in the atmosphere and its saturation point.
The higher this deficit, the more the surrounding air sucks water from the soil and plants, drying them out and creating conditions more conducive to fires.
Other studies have previously demonstrated that DPV is one of the main factors linking human-caused climate change to increased wildfires.
The researchers then calculated the contribution of the 88 companies' GHG emissions to the increase in global average temperature.
These calculations determined that during the study period, the VPD increased by 11.2% due to rising temperatures, caused in part by emissions attributable to these companies.
The methods of the study are part of a still young discipline called attribution science, which is increasingly used in climate models.
In a report published in 2019, Natural Resources Canada explains that attribution science assesses how the probability or intensity of an extreme event, or more generally, a category of extreme events has changed. as a result of increased atmospheric concentrations of GHGs from human activity.
Jennifer Baltzer, associate professor in the department of biology at Wilfrid Laurier University in Ontario, says it's increasingly common for scientists to make this connection and affirm it loud and clear. . She's not surprised by the results of the study, given those that came before her.
Last year, studies directly attributed rising emissions and global warming to heat waves that hit Europe, says- her.
When science makes the link between climate change and disasters
Researcher Carly Phillips says her main motivation was to try to establish the link with the activity of the big emitters, especially in light of research and investigations showing that oil companies had been aware for decades of the danger. global warming linked to their activities.
This study shows in part the link between these companies, their emissions and climate impact, which will hopefully result in them being held financially responsible for their contribution to wildfires, concludes- it.
The Canadian Association of Petroleum Producers (CAPP) explains in an email that it holds a different point of view from the group that produced the study, but concedes that the necessary efforts to reduce greenhouse gas emissions must be continued.
Canada's oil and natural gas industry is one of the largest investors in emission reduction innovation, writes Jay Averill, spokesperson for the Canadian Oil and Gas Industry. CAPP.
He adds that Canadian natural gas can play an important role in reducing global carbon emissions by exporting it to countries that still use coal-fired power plants.< /p>
Jatan Buch, a researcher at Columbia University in New York, believes that the new study, in which he was not involved, demonstrates with solid evidence the impact of emissions from some companies.
He adds, however, that while research shows that vapor pressure deficit (VPD) is a key factor in the spread of a wildfire, other factors also come into play, including the volume of precipitation and early season snow accumulation, as well as prescribed burning and fire suppression practices. /p>
With information from Benjamin Shingler
