Zagreb, December 16, 2022

Ivana Čavlina Tomašević defended the Cotutelle PhD

Our member, Ivana Čavlina Tomašević, Ph.D. defended her doctorate at the Department of Geophysics, Faculty of Science, University of Zagreb on December 16, 2022 with a research topic in the field of silvometeorology. The research is the first in Croatia to link the fire behavior and weather conditions. The dissertation entitled "Analysis of fire weather conditions during catastrophic fires in Croatia and Australia" was defended twice as a Cotutelle PhD, which is the first such doctorate in the scientific field of geophysics in Croatia per agreement between the University of Zagreb, Croatia and Macquarie University in Sydney, Australia. The doctorate at the Macquarie University was awarded on November 9, 2022, after an international peer review process which included three experts in the field of fire weather. Čavlina Tomašević received a scholarship from Macquarie University for this Cotutelle PhD and spent a year in Sydney conducting this research in cooperation with the Bureau of Meteorology and Tasmania Fire Service.

The goal of the research was to analyze weather conditions during catastrophic wildfires in Croatia and Australia. The case study from Croatia included the Split from July 2017 and from Australia included the Forcett-Dunalley megafire from January 2013. The latter created a firestorm in the form of pyroCumulonimbus (pyroCb), the first ever in Tasmania. The research has showed that both wildfires were wind driven from the ignition. In the case of Split, the ignition of the wildfire coincided with an episode of strong downslope NE bura windstorm, and in Dunalley wildfire with strong NW wind. The antecedent conditions in both cases included the drier and warmer-than-average periods in months’ prior the wildfires, which contributed to drying out fuels in the area and extreme fire danger rating. Important findings on atmospheric dynamics in the Split case included a long amplitude and shortwave upper-level trough, which caused the cool and dry air outbreak, and a deep bura flow. The pyroCb development in the case of the Dunalley was triggered by the highly unstable atmosphere and the line of convergence over the wildfire’s area in the hours prior to the cold front passage.

Scientific contribution of the research:

- Provided a comprehensive literature review of fire weather together with past and future climate influencing fire risk at the Adriatic Coast in Croatia and in southeast Australia.

- Drew similarities between dynamic atmospheric processes and mechanisms that occurred in chosen wildfire cases.

- Implemented a coupled fire-atmosphere model for the first time in Croatia and provided the numerical evidence on fire-atmosphere interactions along the Adriatic Coast.

- Presented the recommendations for the improvement of fire management in Croatia.

Two scientific papers have been published to date. The first paper presents previous research in the field of silvometeorology from Croatia and Australia (Tomašević et al., 2022), and the second paper presents the reconstruction and meteorological analysis of the Split wildfire (Čavlina Tomašević et al., 2022). This is the first such meteorological analysis published in an international scientific journal, which gave the international scientific community an insight into the wildfire problem in Croatia.

Tomašević, I.Č., Cheung, K.K.W.; Vučetić, V., Fox-Hughes, P., 2022. Comparison of Wildfire Meteorology and Climate at the Adriatic Coast and Southeast Australia. Atmosphere 2022, 13, 755. https://doi.org/10.3390/atmos13050755.

Čavlina Tomašević, I., Cheung, K. K. W., Vučetić, V., Fox-Hughes, P., Horvath, K., Telišman Prtenjak, M., Beggs, P. J., Malečić, B., Milić, V., 2022. The 2017 Split wildfire in Croatia: Evolution and the role of meteorological conditions. Nat. Hazards Earth Syst. Sci. Discuss. 22, 3143–3165. https://doi.org/10.5194/nhess-2022-116.

Ivana Čavlina Tomašević defended her doctorate at the Department of Geophysics, Faculty of Science, University of Zagreb on December 16, 2022