Sarah Meier

Sarah Meier, Eric Strobl & Robert J. R. Elliott

The Great Fire of 1910 in the northwestern United States burnt more than 1.2 million hectares in just two days and stands as one of the largest wildfires ever recorded. While it is known for having led to the introduction of a rigorous fire suppression regime that lasted for much of the 20th century, it also generated a considerable amount of smoke far beyond the burnt areas that is likely to have impacted the health of those exposed. This paper examines the short- and long-term impact of this fire-sourced smoke pollution on children, combining historical data with smoke emission and dispersion modelling. The econometric results indicate a 119% increase in excess mortality during the week of the fire and a decrease of 4-14% in later-life socioeconomic status scores 20 and 30 years after the event. This research offers novel insights into wildfire smoke repercussions on health and long-run human capital formation in a setting where avoidance behaviour was minimal.

Sarah Meier, Ben Balmford, Michela Faccioli, & Ben Groom

Biodiversity is a multifaceted component of natural capital and challenges traditional valuation methods. We therefore propose a cost-based approach, novel in its application to biodiversity, and seek to define a metric that accurately reflects within-class substitutability of different biodiversity attributes. Preferences from the British public over key biodiversity attributes are elicited through a choice experiment, while eschewing problematic money-biodiversity trade-offs, and compared to the preferences of experts. The findings indicate a consensus between public and expert preferences regarding within-class substitutability, prioritising species richness and reduced extinction risk over increased intactness. Furthermore, we apply the preference-derived metric in a case study of optimal conservation restoration policy for Great Britain to determine shadow prices which enable policymakers to value biodiversity within cost-benefit analyses. Targeting the Kunming-Montreal Global Biodiversity Framework 30-by-30 commitment, our proposed utility metric suggests a biodiversity shadow price of approximately £45 million per 1% of the available uplift. Thus, this paper establishes preference-aligned marginal rates of substitution for within-class attributes, determining a metric which is applied to calculate a robust cost-based shadow price for across-class substitution.

Matthew W. Jones et al.

Climate change contributes to the increased frequency and intensity of wildfires globally, with significant impacts on society and the environment. However, our understanding of the global distribution of extreme fires remains skewed, primarily influenced by media coverage and regionalised research efforts. This inaugural State of Wildfires report systematically analyses fire activity worldwide, identifying extreme events from the March 2023–February 2024 fire season. We assess the causes, predictability, and attribution of these events to climate change and land use and forecast future risks under different climate scenarios. During the 2023–2024 fire season, 3.9×106 km2 burned globally, slightly below the average of previous seasons, but fire carbon (C) emissions were 16 % above average, totalling 2.4 Pg C. Global fire C emissions were increased by record emissions in Canadian boreal forests (over 9 times the average) and reduced by low emissions from African savannahs. Notable events included record-breaking fire extent and emissions in Canada, the largest recorded wildfire in the European Union (Greece), drought-driven fires in western Amazonia and northern parts of South America, and deadly fires in Hawaii (100 deaths) and Chile (131 deaths). Over 232 000 people were evacuated in Canada alone, highlighting the severity of human impact. Our analyses revealed that multiple drivers were needed to cause areas of extreme fire activity. In Canada and Greece, a combination of high fire weather and an abundance of dry fuels increased the probability of fires, whereas burned area anomalies were weaker in regions with lower fuel loads and higher direct suppression, particularly in Canada. Fire weather prediction in Canada showed a mild anomalous signal 1 to 2 months in advance, whereas events in Greece and Amazonia had shorter predictability horizons. Attribution analyses indicated that modelled anomalies in burned area were up to 40 %, 18 %, and 50 % higher due to climate change in Canada, Greece, and western Amazonia during the 2023–2024 fire season, respectively. Meanwhile, the probability of extreme fire seasons of these magnitudes has increased significantly due to anthropogenic climate change, with a 2.9–3.6-fold increase in likelihood of high fire weather in Canada and a 20.0–28.5-fold increase in Amazonia. By the end of the century, events of similar magnitude to 2023 in Canada are projected to occur 6.3–10.8 times more frequently under a medium–high emission scenario (SSP370). This report represents our first annual effort to catalogue extreme wildfire events, explain their occurrence, and predict future risks. By consolidating state-of-the-art wildfire science and delivering key insights relevant to policymakers, disaster management services, firefighting agencies, and land managers, we aim to enhance society's resilience to wildfires and promote advances in preparedness, mitigation, and adaptation. New datasets presented in this work are available from https://doi.org/10.5281/zenodo.11400539 (Jones et al., 2024) and https://doi.org/10.5281/zenodo.11420742 (Kelley et al., 2024a).