Graduate School in Physics and Astrophysics ------------------------------------------- ANNUAL REPORT ------------------------------------------- name:Marta Magnani email:marta.magnani@edu.unito.it ciclo:XXXIV year completed (1,2 or 3):2 supervisor:Antonello Provenzale (CNR) and Guido Boffetta ------------------------------------------- GRADUATE SCHOOL COURSES code:19 title:Case Studies in the History of Physics teacher:Matteo Leone hours:8 ------------------------------------------- CONFERENCES title:European Geoscience Union General Assembly place:online (owing to COVID-19) webpage: www.egu2020.eu days:5 (4-8 May 2020) talk (Y/N):Y (short presentation) poster (Y/N):Y ------------------------------------------- WORKSHOP title: Climate modelling: different approaches and applications place: Pavia webpage: www.iusspavia.it/-/climate-modelling-different-approaches-and-applications days:1 (4 December 2019) talk (Y/N):N poster (Y/N):N ------------------------------------------- VISITS AND STAGES institution:Utrecht University, Centre of Complex System Studies (CCSS) place:Utrecht, The Netherlands starting date:10/01/2020 days:58 --------------------------------------------------- Research activity/Publications in the current year During the second year of my PhD I carried on the two topics of 1) modelling of carbon dioxide fluxes in extreme environments and 2) istudy of turbulent mixing of stratified fluids. The first topic focused on three main case-study: high-altitude, high-latitude and fire-prone ecosystems. A multi regression model that identifies the main drivers of both carbon dioxide emissions and uptake from soil and vegetation was obtained for both the high-altitude alpine tundra of Nivolet plain (Gran Paradiso National Park, IT) and the high-latitude arctic tundra of Bayelva Basin (Svalbard Islands, NO). The same meteoclimatic and ecological variables drive fluxes variability in those two environments, which allows for a comparation between sites. The model of alpine fluxes was published on Science of the Total Environment [1] in August, while a paper on arctic fluxes variability is now in preparation. Results were also presented at EGU Conference in two posters and a short online presentation [2,3]. The third case-study is related to the assessment of carbon dioxide emissions due to wildfires. A process-based model for the reproduction of characteristic fire frequencies in the main fire-prone ecosystems and fire-vegetation mutual interactions was implemented during my visit at Utrecht University. Expenses were covered by the awarded grant of the Swaantje Mondt Fund for visiting PhDs, for which I applied in 2019 (https://www.uu.nl/en/news/new-travel-fund-call-for-foreign-phd-candidates). Preliminary results were presented at EGU conference [4] and a paper will be submitted on The American Naturalist in the next month. The second topic of my research is the mixing of two unstably stratified fluids in the Rayleigh-Taylor configuration. This configuration was used to address a sedimentation problem, where the heavier phase is a particle-laden fluid while the lighter phase is a limpid fluid. The effect of particles on turbulence development and fluids mixing was assessed and a paper will be submitted on Journal of Fluid Mechanics in the next few days. [1] Magnani M., Baneschi I., Giamberini M., Mosca P., Raco B., Provenzale A., Drivers of carbon fluxes in Alpine tundra: a comparison of three empirical model approaches, Science of The Total Environment, 2020, Vol 732, 139139, ISSN 0048-9697, https://doi.org/10.1016/j.scitotenv.2020.139139. [2] https://meetingorganizer.copernicus.org/EGU2020/EGU2020-3919.html [3] https://meetingorganizer.copernicus.org/EGU2020/EGU2020-2956.html [4] https://meetingorganizer.copernicus.org/EGU2020/EGU2020-13840.html