Leverhulme Wildfires Centre

Welcome to the second Giraffe Team Bulletin!

Approximately every two months, we share a Giraffe Team bulletin, providing you with an update on the latest from each of our six teams.  We hope you enjoy the bulletins and that it helps you keep abreast of our research. Please do get in touch if you want to find out more about anything in the bulletin (either wildfire@imperial.ac.uk or contact the researchers involved).

You can find out more about each one of the “Giraffe Teams”, including their overall aims and objectives, and specific projects, here.

Just Fire Giraffe Team

A paper on global expert elicitation of present-day human-fire interactions, led by Just Fire team member Cathy Smith with contributions from several other team members, will be published in a Special Issue of the Philosophical Transactions of the Royal Society B on novel fire regimes under climate changes and human influences: impacts, ecosystem responses and feedbacks. The paper presents data analysis on the distribution of fire use and policy interventions from the Global Fire Use Survey of that elicited and systematised knowledge about human fire use from experts, including academics and practitioners. Look out for that in April 2025.

Just Fire Team members Amos Chege Muthiuru, Adriana Ford and James Millington have been successful in bidding for a grant from the ESRC Impact Accelerator Award Social Science Impact Fund via King’s College London. The award will support integration of indigenous knowledge into wildfire management in multi-use landscapes of southern Kenya. Through workshops and other activities in 2025, the project aims to facilitate knowledge exchange, co-develop a holistic landscape fire management plan that includes multiple stakeholders across multi-use landscapes, and create wider awareness of fire management through local media. In some ways this work will build on a previous workshop funded by the Centre to explore decolonising fire management practices and what is needed for fire management in a Kenyan context.

Finally, big congratulations to former Centre PhD student, and current Just Fire alumni-affiliate, Abi Croker who recently successfully defended her PhD! Abi is now Postdoctoral Research Associate at Princeton University, working with Prof. Simon Levin to explore the drivers and impacts of carbon-based payment for ecosystem service schemes on fire-adapted ecological systems across the tropical savanna-forest transitional zone.

Photo: Dr Abi Croker visiting the UNESCO world heritage site Kit-Mikayi in Kenya, a unique cultural and religious site of the Luo people

Fire-Veg Giraffe Team

The Fire-Vegetation Giraffe Team has finalized the results on clustering the world according to the seasonal cycles of potential productivity (GPP) and potential atmospheric humidity (VPD) to examine global differences in fire properties (Figure 1).

Figure 1. Global map showing regions of similar patterns in the magnitude and seasonal phasing of gross primary production (GPP) and vapour pressure deficit (VPD) based on x-means clustering of data at 10 km resolution. Maps showing the geographic distribution of individual clusters are given in Supplementary Material.

This bottom-up approach of defining pyromes from the biophysical drivers distinguishes it from previous fire regime classifications because it starts with the drivers of wildfires to get at the different fire regimes instead of starting with observed differences in remotely sensed fire data. This approach means that the resulting fire regimes are not fixed but emerge because of the conditions in the underlying drivers (GPP for fuel build-up and VPD for fuel drying). As such, it provides flexibility for the fire regimes to change if the conditions in the underlying drivers did under a changing climate and provides the opportunity of developing a simple but robust parameter-sparse fire model. Redundancy analysis (RDA) was used to explore the variation in fire properties between clusters. The RDA showed that the clusters explained 23% of the variation in fire properties, with weightings on the first four axes of 48%, 34%, 13% and 5% respectively (see Figure 2).

Figure 2. Interquartile ranges of fire properties by clusters. The clusters are numbered from 1 to 18. The seven fire properties are average burnt area (km2), average fire size (km2), average number of ignitions, average fire speed (km/day), average fire duration (days), average seasonal concentration, and average carbon emission (gC/m2).

The clusters are affected human activity to a varying degree, with some clusters exhibiting for example a combination of high population and road density with very low burnt area and other fire properties (Cluster 1) or high pasture area along with high number of ignitions, high burnt area and high carbon emissions (Cluster 11). However, given that the clusters emerge solely from differences in the seasonal cycles of potential productivity (GPP) and potential atmospheric humidity (VPD), the influence of various types of human activity on these fire regimes can be understood as secondary and delimitated by the underlying biophysical conditions (which provide the conditions under which such human activity occurs).

Table 1. Eigenvalues, and the percentage of wildfire trait variation explained by successive redundancy analysis (RDA) axes (constrained by clusters) and residual principal components (PC).

Climate Giraffe Team

The Climate Team is advancing research on wildfire dynamics and atmospheric composition, focusing on peatlands and northern latitudes. A key breakthrough is the first general ignition probability curve for all peat types, forming the basis of INFERNO-PEAT, a new climate forecast model. The TUC-Imperial collaboration has an advanced journal paper draft for submission this summer and a presentation planned for EGU 2025. Dimitra (TUC) will visit Imperial to complete further smouldering peat experiments. Despite unforeseen challenges, the team remains dedicated to understanding peatland fire behaviour and its climate impact, contributing valuable insights to wildfire and atmospheric research.

Figure 3: Schematic summarizing the new parameterizations introduced as part of INFERNO-peat, the input variables, and their sources. Source: Blackford et al 2024

Air Quality Giraffe Team

The team have recently started a British Council funded grant in collaboration with existing partners in Thailand and Laos.  Two aspects are covered by the grant – firstly work to improve robustness of the existing small sensor network for real-time air quality data, and secondly for capacity building between the two partner countries in relation to management of the use of fire and air quality impacts. For this second focus, a workshop is being planned (either for later in 2025 or early 2026) to bring key stakeholders together. The workshop is planned to include aspects of training on use of large-scale earth observation/atmospheric model datasets of air quality, along with more localised use of in-situ data from monitoring stations.  It is hoped that a practical training session of a prescribed fire can also be included. A social science aspect will also be included in the workshop as knowledge and experience of how policies or schemes may impact the use of fire and what results this could have on improving air quality.

Fire Info Giraffe Team

The Earth Observation Climate Information Service (EOCIS) project is coming to an end. Zixia Liu and others at KCL have been involved in producing independent estimates of fire-related emissions of CO derived from geostationary satellites. These satellites are located over the Equator and provide frequent observations (<15 minutes) of fire radiative power (FRP), which can then be integrated temporally and converted into trace gas emissions by using suitable emission factors. These estimates are completely independent of other estimates that rely on first calculating the amount of standing biomass, the fraction of the biomass removed by the fire and so on.

Figure4: Fire CO emissions over 2022 from MSG, GOES-E, GOES-W, and HIM

The above plots show fire CO emissions over 2022 from MSG, GOES-E, GOES-W, and HIM (covering, respectively, Europe/Africa, Americas, Pacific/West Coast of North America and SE Asia/Australia). Dr Liu has also been doing some comparisons between these estimates and other (mostly) satellite derived estimates. Below is a comparison of Himawari hourly estimates Total Particulate Matter (TPM) over SE Asia and GFAS estimates for Feb 2022. Spatial resolution for these two datasets is around 0.1degree.

These data might be useful for others, for e.g. driving or testing models.

Figure 5: comparison of Himawari hourly estimates Total Particulate Matter (TPM) over SE Asia and GFAS estimates for Feb 2022

WIR3 Giraffe Team

No update this time!

March 2025 (following 20th Feb 20265 meeting)

Thank you to all the Giraffe Team leads for providing the updates.