Here we introduce Part 1 of a special issue series arising from the IX International Conference on Forest Fire Research, held 14–18 November 2022, Coimbra, Portugal. This issue comprises eight papers covering a wide variety of topics. All papers in the issue are published Open Access.

Projections of fire activity in southeastern France show that very large increases in fire metrics arise mostly from an intensification in the already fire-prone region during the core of the current fire season and only to a lower degree from an expansion of the fire-prone region and lengthening of the season.

We leveraged Bayesian spatio-temporal modelling to disentangle the contributions of climatic and non-climatic drivers for fire activity in Mediterranean France. We showed that recent fire-weather increase caused the increase of fire probability in the west; but in the east, it was over-compensated by a reduction of escaped-fire probability.

Temperature perturbations resulting from solar heating of Earth’s surface can induce buoyancy-driven wind turbulence. Using experimental numerical simulations, this work investigates how atmospheric wind turbulence, under different atmospheric conditions, can change the energy transfer within the fire area and subsequently impact fire behaviour.

Multi-modal observations of fire behaviour and overlying atmospheric turbulence were carried out for four wind-driven gorse bush experimental fires. Novel image velocimetry analysis outlined the dynamics and scales of motion of fire sweeps in relation to overlying atmospheric coherent turbulent structures. Results are useful for evaluating coupled fire–atmosphere model simulations.

Oxidative pyrolysis gases were measured in a wind tunnel and small prescribed burns using two analytical methods. Gas composition measured by FTIR spectroscopy differed between wind tunnel and field fires. The relative amount of the primary fuel gases (CO, CH₄) was not significantly affected by fire location.

In wildland–urban interface fires, particulates from combustion of natural vegetative and human-made fuels may have deleterious effects on the environment. Particulate samples were taken during both flaming combustion and smouldering combustion states. The morphology of the generated particulates is greatly influenced by the state of combustion for both fuels.

Smouldering fire in peatland is one of the largest wildfire phenomena on Earth that can burn slowly deep underground without flame. Laboratory experiments on tall peat soil samples revealed burning, propagation and emission physics of deep smouldering wildfires in peatland.

Post-fire treatment consisting of leaving burnt logs and felled branches in close contact with the forest floor promotes the ability of the soil to sustain high values of multiple functions simultaneously in the medium term after wildfire, as compared to straw mulching application.