Potential impact of climate change on length of ignition danger season in Mediterranean shrubland of North Sardinia

The flammability of vegetation is influenced by several factors that include structural properties, chemical properties and moisture content. The fuel moisture content is one of the critical parameters affecting fire ignition and fire propagation. In addition, live fuel moisture content (FMC) plays a crucial role in determining the fire danger in Mediterranean shrubland. In these types of ecosystems, a decrease in vegetation moisture during drought season can determine severe fire danger when combined with extreme meteorological conditions (i.e. strong summer wind). In this context, more prolonged drought seasons induced by climatic changes is likely to influence directly the FMC and the length of critical periods of high ignition danger. The main aim of this work is to propose a methodology to identify the length of critical periods of high ignitability danger in maquis ecosystems by using meteorological data in order to predict the potential impacts at local scale of climate change on the length of fire danger season in Mediterranean shrubland. Moisture content of live fuel was determined periodically during five years on four shrub species (Cistus monspeliensis L., Juniperus phoenicea L, Pistacia lentiscus L., and Rosmarinus officinalis L.). Some meteorological drought codes were also calculated. Threshold values of codes for estimating the starting and ending dates of high ignition danger periods were estimated by percentile and logistic analysis. Then, the potential climate change impacts on length of ignition danger season in Mediterranean Basin shrublands was determined using the meteorological code and future climate scenarios at local scale derived from an advanced high resolution Regional Climate Model.