Centre for Research and Technology of Agro-Environment and Biological Sciences, CITAB, University of Trás-os-Montes and Alto Douro, Portugal.
Centre for Research and Technology of Agro-Environment and Biological Sciences, CITAB, University of Trás-os-Montes and Alto Douro, Portugal; Instituto Dom Luiz, Faculdade de Ciências da Universidade de Lisboa, Lisboa, Portugal.
Sci Total Environ. 2018 Aug 1;631-632:534-549. doi: 10.1016/j.scitotenv.2018.03.044. Epub 2018 Mar 16.
Heat waves (HW) can have devastating social, economic and environmental impacts. Together with long-term drought, they are the main factors contributing to wildfires. Surprisingly, the quantitative and objective analysis leading to the identification and characterization of HW in current and future climate conditions as well as its influence on the occurrence of extreme wildfires (EW) has never been performed for Portugal and are the main objectives of this study. For this reason, we assess HW in recent past and future climate based on a consistent high resolution meteorological database and have compared their occurrence with long and reliable, precise and detailed information about Portuguese fire events. Results include the characterization of HW frequency, duration, seasonality and intensity for current and different future climate conditions and their relationship with EW occurrence. We detected 130 HW between 1981 and 2010, concentrated between May and October and highest values in July and August. The highest HW number and duration is found over the Northeast corner and the south of the country while highest amplitudes are typically located in central area. HW characteristics present high inter-annual variability but are clearly associated to the temporal and spatial distribution of EW: 97% of total number of EW were active during an HW, 90% of total EW days were also HW days; 82% of the EW had duration completely contained in the duration of an HW; and, 83% of EW occurred during and in the area affected by HW. Our results also show that HW should increase in number, duration and amplitude, more significantly for RCP 8.5, and for the 30-year periods near the end of the 21st century. Findings of this study will support the definition of climate change adaptation strategies for fire danger and risk management.
热浪（HW）会对社会、经济和环境造成破坏性影响。与长期干旱一起，它们是导致野火的主要因素。令人惊讶的是，目前和未来气候条件下识别和描述 HW 以及其对极端野火（EW）发生的影响的定量和客观分析，在葡萄牙从未进行过，这也是本研究的主要目标。为此，我们根据一致的高分辨率气象数据库评估了最近过去和未来气候中的 HW，并将其发生情况与葡萄牙火灾事件的长期、可靠、精确和详细信息进行了比较。结果包括了当前和不同未来气候条件下 HW 的频率、持续时间、季节性和强度的特征描述，以及它们与 EW 发生的关系。我们在 1981 年至 2010 年期间检测到了 130 次 HW，主要集中在 5 月至 10 月，7 月和 8 月达到最高值。HW 数量和持续时间最高的是东北地区和该国南部，而最高幅度通常位于中心区域。HW 特征具有高度的年际可变性，但与 EW 的时空分布明显相关：总 EW 数量的 97%是在 HW 期间发生的，总 EW 天数的 90%也是 HW 天数；82%的 EW 持续时间完全包含在 HW 的持续时间内；83%的 EW 发生在 HW 期间和受 HW 影响的区域内。我们的研究结果还表明，HW 的数量、持续时间和幅度将增加，在 RCP 8.5 情景下增加更为显著，并且在 21 世纪末的 30 年期间内增加更为显著。本研究的结果将支持制定适应气候变化的战略，以应对火灾危险和风险管理。
