Movement restrictions during the COVID-19 pandemic were associated with a 12.3% reduction in the number of fire incidents worldwide in the first half of 2020. In Australia, the decrease reached 79%. The results of a study published in the scientific journal Cell Reports Sustainability show how human activity can contribute both to the initiation of fires and to their prevention and control.
The investigation compared fire activity between January and June 2020 with patterns recorded between 2013 and 2019, using satellite observations, weather data, government lockdown measures, and information on human mobility.
The results reveal significant regional differences. In addition to the 79% drop in Australia, the United States recorded a reduction of almost 23%. In contrast, incidents increased by 31% in Colombia and 70% in Honduras. According to the researchers, these differences may reflect the dual role of people in the dynamics of fires: on the one hand, they can trigger them, on the other, they contribute to surveillance, management and response to incidents.
“The relationship between human activity and fires is very complex,” says Jianghao Wang of the Chinese Academy of Sciences, the study’s first author. The researcher considers that the pandemic provided an opportunity to better understand this relationship by temporarily reducing outdoor human activity.
Fewer fires in forests and meadows
The reduction was particularly pronounced in forests and meadows, where the number of occurrences decreased by more than 27% and 8%, respectively. The results suggest that these ecosystems are especially vulnerable to fires originating from human activities.
The team also analyzed the impact of prescribed burns, used deliberately to reduce the amount of vegetation fuel and limit the risk of larger fires. In 12 countries with detailed records, the area covered by these interventions in 2020 fell to about half the historical average.
Even after accounting for the effects of reduced prescribed burns, the number of occurrences in the 12 countries decreased by more than 27% after the restrictions were imposed.
However, the reduction in human activity did not always result in fewer fires. In some regions, the reduction of management, surveillance and patrolling operations could have delayed detection and response to incidents, contributing to the observed increase.
Regional fire management adapted to each region
The researchers argue that prevention strategies should take into account the characteristics of each territory. In regions where fires are predominantly ignited by people, restricting activities involving fire could help reduce occurrences. In areas where human presence is lower and management resources are scarce, strengthening surveillance and patrolling could be more important.
The team therefore warns of the limits of a one-size-fits-all approach to fire prevention. “Human activity can act as a double-edged sword with respect to fires,” says Jianghao Wang, emphasizing that the role of people should be considered in the specific context of each region.
The study demonstrates an association between the reduction of human activity during lockdowns and the decrease in occurrences, but also shows that fire management depends on distinct factors, including prevention, surveillance and response capacity.
