Numerical investigation of atmosphere-fire interactions during high-impact wildland fire events in Greece

This study investigated two high-impact wildland fire events that took place on 23 July 2018 in Attica Region, Central Greece during extreme prevailing weather conditions. The tragic aftermath was 102 life losses in MATI fire event, the largest number of deaths from a fire event in history of the country. The synoptic analysis revealed the presence of a positively tilted trough over the Central Mediterranean and Balkans, propagating eastwards and interacting with the subtropical jet, resulting in a strong westerly flow over Greece. Several surface stations in the wider area recorded wind gusts exceeding 20 m s(-1) between 12:00 and 17:30 UTC. The online coupled atmosphere-fire model WRF-SFIRE was utilized in order to simulate these extreme fire events and to investigate the role of the complex terrain to the mean flow and fire behavior. The numerical simulations revealed the presence of induced orographic waves, paths of high winds on the lee-slopes, transient resemblance of a hydraulic jump downstream of Penteli Mt. (MATI), while indicated a downward transport of energy and momentum during the maximum wind speed occurrences. The turbulent and dynamically unstable conditions on the lee-slopes of Gerania Mts. (KINETA) and Penteli Mt. contributed to the flow kinetic energy. Quite different influences of topography in each fire event were found, where the isolated Gerania Mts. contributed to warmer, drier and windier conditions leeward, while Penteli Mt. had a lesser impact on atmospheric variables downstream.

Automated summary

This study investigated two high-impact wildland fire events that occurred on July 23, 2018 in the Attica Region of Central Greece during extreme weather conditions. The analysis revealed the significant role of complex terrain in influencing fire behavior and airflow dynamics.