Benefits and limits of Integrated Fire Management for climate change adaptation: a global quantitative assessment

Wildfires are increasing in severity and harm to humans, creating a pressing climate change adaptation challenge. Current firefighting-focused management approaches in the Global North can drive fuel accumulation and increased fire intensity. In contrast, Indigenous peoples and local communities have used controlled burning to successfully co-exist with fire for at least 50,000 years. Consequently, intentional and controlled burning of landscape vegetation has been suggested as a strategy to adapt to climate-altered fire regimes in an approach known as Integrated Fire Management.  

Here, we present the first quantitative global assessment of controlled burning in Integrated Fire Management (IFM) for climate change adaptation, using the JULES-INFERNO dynamic global vegetation model coupled to the WHAM! agent-based model of human fire use and management. WHAM! has agent types to represent both fire exclusionary, suppression-oriented and pyro-inclusive, controlled burning (IFM) land manager approaches. This new online coupling includes novel representations of human fire use seasonality and fireline intensity. Modelled fireline intensity, accounting for climate, fuel and human management now drives fire-induced vegetation mortality in JULES. Hence, the WHAM-JULES-INFERNO ensemble can assess the human and climate drivers of future fire intensity, and also fire-vegetation feedbacks resulting from contrasting management approaches.  

We explored two Shared Socio-Economic Pathways (SSP1.26 and SSP3.70), using gridded socio-economic capitals consistent with the SSP scenarios and biophysical forcings from three ISIMIP 3b ESMs. Additionally, we drew on WHAM! functionality to complement the SSPs scenarios with two IFM scenarios: “IFM-max”, in which the world turns increases controlled burning through IFM; and “Suppression-max”, in which IFM is abandoned and the world focuses on fire exclusion and suppression. 

We find that IFM can play an important role in constraining future fire hazard and intensity. However, we also identify barriers and confounding factors that may limit implementation. Notably, even in a low emissions-scenario (SSP1.26) with increased adoption of IFM, fire hazard is still 40.0% [32.1%-49.6%] higher in 2100 than in 2015. Importantly, we find that the impact of IFM is smaller than general land management changes resulting from economic conditions of the SSPs. For example, for both IFM scenarios mean 2100 fire intensity is higher in SSP1.26 than SSP3.70 because changes in fire management do not offset increases in intensity due to reduced human fire use between the SSPs. Specifically, in SSP1, rapid economic growth in low-income countries (e.g. sub-Saharan Africa) sees fire use in agriculture and forestry increasingly replaced by chemicals and machinery.  

Our results suggest that incremental changes in land and fire management may be an insufficient response to the combined impacts of socio-economic and climate change. Transformative approaches that change fundamental relationships between economic development and fire suppression could in principle address this adaptation shortfall, but will need to grapple with how to integrate and maintain low-intensity fire in capital-intensive land systems on an increasingly flammable planet.