EGU24-6004, updated on 08 Mar 2024
https://doi.org/10.5194/egusphere-egu24-6004
EGU General Assembly 2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.

Meteorological environments leading to two large fires in Southern Portugal

Carolina Purificação1,2, Cátia Campos1,2, Alice Henkes3, Stergios Kartsios4, and Flavio T. Couto1,2,5
Carolina Purificação et al.
  • 1Instituto de Investigação e Formação Avançada (IIFA), University of Evora, Évora, Portugal (ana.purificacao@uevora.pt)
  • 2Institute of Earth Sciences (University of Evora Pole), Earth Remote Sensing Laboratory — EaRS Lab, University of Evora, Évora, Portugal
  • 3Leipzig Institute for Meteorology, Universität Leipzig, Leipzig, Germany
  • 4Department of Meteorology and Climatology, School of Geology, Aristotle University of Thessaloniki (AUTh), Thessaloniki, Greece.
  • 5Physics department, University of Evora, Évora, Portugal

The study is a step forward in the characterization of meteorological environments that favour the evolution of large and extreme fires in Southern Portugal. The region has some fire-prone areas which are recognized by the mega fires occurred in 2003, 2005, and 2018. Two numerical simulations were performed using the Meso-NH non-hydrostatic research model and used to investigate in detail the atmospheric environments of two large fires that occurred on 18th July 2012 and 19th June 2020. The simulations were configured using two nested domains with a 375 km × 375 km grid domain (D1) at 2.5 km horizontal resolution and a 150 km × 150 km domain (D2) at 500 m resolution added before the start of the fires. The vertical grid was configured with 50 stretched levels following the terrain. The initial and boundary conditions are provided by the 6-hourly operational ECMWF analyses. The large-scale circulation has been characterised using data obtained from the ECMWF's Meteorological Archival and Retrieval System. In addition to the large-scale circulation, namely the positioning of the Azores anticyclone and the thermal low development over the Iberian Peninsula, the results have shown the important role played by regional orography in creating favourable fire weather conditions. For instance, the high-resolution simulations showed the high daytime temperatures and sometimes overnight, low humidity, and strong wind gusts that favour fire spread. In July 2012, the typical sea breeze circulation affected the fire evolution, whereas the intense downslope winds favoured the fire spread in June 2020. The study brings useful guidelines for interpreting the impact of different mesoscale environments that may produce large fires, namely the orographic effects that can increase the fire susceptibility and vulnerability of some regions. This study was funded by national funds through FCT-Foundation for Science and Technology, I.P. under the PyroC.pt project (Ref. PCIF/MPG/0175/2019).

How to cite: Purificação, C., Campos, C., Henkes, A., Kartsios, S., and Couto, F. T.: Meteorological environments leading to two large fires in Southern Portugal, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6004, https://doi.org/10.5194/egusphere-egu24-6004, 2024.