Report on potential fire behaviour and exposure under climate change scenarios (D4.4c)

Fires have a crucial role within Mediterranean ecosystems, with impacts both negative and positive on all biosphere components and with reverberations on different scales. Fire determines the landscape structure and plant composition, but it is also the cause of enormous economic and ecological damages, beside the loss of human life (Haas et al., 2015).In the Mediterranean area, the occurrence of fires is mainly related to human activities (FAO, 2013) and varies considerably from year to year, suggesting a strong dependence on fire-weather conditions, such as drought and heat waves, as highlighted by Bedia et al. (2015) and Urbieta et al. (2015). However, during the past decades, fire frequency and fire extent have changed (Pausas and Fernández-Muñoz, 2012; Marques et al., 2011; Spano et al. 2014; Turco et al. 2016) as well as the burning patterns, especially in terms of expansion of the fire-prone areas (Arianoutsou et al., 2008; Fernandes et al., 2010; Koutsias et al., 2012) and lengthening of the fire seasons (e.g., Lavalle et al., 2009; Koutsias et al., 2015).These changes have been linked to different transformations that have affected the entire Mediterranean basin concerning not only climate and weather, but also land use, socio- economic processes, and fire management (eg, Moreira et al., 2011; Viedma et al., 2015; Spano et al., 2014; Turco et al., 2016).It is also widely recognized that wildfire risk and exposure are likely to be exacerbated by climate change (IPCC, 2014). In fact, a substantial increase in temperatures and drought conditions will likely alter the actual fire regime and may lead to an increase in fire hazard and risk. Indeed, extreme weather events, such as extended drought, heat waves and strong winds, facilitated the incidence and the behaviour of recent forest fires in Southern Europe, especially if supported by a general lack of forest management activities.

Within this context, understanding local climate change impacts and assessing vulnerabilities and risks are the first steps to provide information for identifying measures to adapt to climate change impacts and thus prepare effectively the landscape and the society for future risks imposed by climate change. Vulnerability and risk assessment under climate change encompasses a number of elements towards the efforts of expressing the complex interaction of different factors that determine the system proneness to be negatively affected. Building on the fire weather index results of Deliverable 4.3 (Atlases of newly developed hazard indexes and indicators), which provided an evaluation of vulnerable areas with respect to the potential of fire occurrence at the regional level under climate change by mapping the spatial and temporal distribution of fire danger, deliverable 4.4c applied high resolution fire spread and behaviour model within representative critical areas (Sardinia, Corsica, and Crete islands). In particular, here we applied FlamMap model (Finney, 2006) which allows simulating thousands of fires and generating burn probability and intensity maps based on the minimum travel time (MTT) algorithm. The final aim of this deliverable was to

• -  estimate and evaluate potential fire characteristics and impacts (burn probability, expected burned areas, conditional flame length),

• -  and identify landscapes prone to large and severe fires, as well as the most relevant areas at high risk

  under two RCP scenarios (2.6 and 8.5), two future scenarios (2026-2045 and 2081-2100), and using three RCM/GCM pairs, developed within the EURO-CORDEX initiative.

  This approach and the results obtained can contribute to mapping fire regime changes due to climate change, and to support fire managers, decision and policy-makers to respond to the potential increase on fire vulnerability and risk.