Ranojutarnja tuča nad južnim dijelom Jadrana

master's thesis

• Title (english): Early morning hail over the southern part of he Adriatic
• Author: Lovro Karaula
• Mentor: Maja Telišman Prtenjak (mentor)
• Mentor: Barbara Malečić (pomoć pri izradi, neposredni voditelj)
• Committee member: Maja Telišman Prtenjak (predsjednik povjerenstva)
• Committee member: Antun Marki (član povjerenstva)
• Committee member: Snježana Markušić (član povjerenstva)
• Committee member: Giuliana Verbanac (član povjerenstva)
• Committee member: Zvjezdana Bencetić Klaić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Geophysics); Zagreb
• Defense date and country: 2024-09-18, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Geophysics; Meteorology and Climatology

Abstract

U ovom je radu korišten meteorološki model WRF-HAILCAST s fokusom na analizi slučajeva ranojutarnje tuče na južnom Jadranu. Ovo je područje specifično po tome što je tuča cešća zimi i nema poslijepodnevnog maksimuma kao što je osobina dnevnih hodova tuče nad kontinentom. Suprotno tome, ističe se jutarnji maksimum u hladnijem dijelu godine. Mehanizmi koji dovode do konvekcije su stoga drukčiji od onih na kontinentu i potrebno je daljnje ispitivanje uzroka konvekcije u ovim uvjetima. Cilj ovoga rada je provesti numeričke simulacije nekoliko odabranih slučajeva zimske konvekcije na južnom Jadranu te procijeniti uspješnost modela u simuliranju tuče i odabranih meteoroloških parametara. U svrhu analize događaja, korištene su sinoptičke karte te radiosondažna mjerenja na meteorološkoj postaji Zadar - Zemunik. Dobiveni rezultati modelski su tada uspoređeni s izmjerenim podacima iz mreže prizemnih meteoroloških postaja DHMZ-a. Uz to, modelirani potencijal razvoja munja (LPI) uspoređen je s izmjerenim podacima udara munja iz LINET mreže, a provedena je i dekompozicija skala strujanja polja vjetra pomoću Barnesovog filtra kako bi se dobila bolja informacija o utjecaju pojedinih skala u ukupnom strujanju vjetra. Rezultati pokazuju da model podcjenjuje veličinu zrna tuče, ali precjenjuje prostornu pokrivenost tučom. Također, model jako dobro prognozira temperaturu i tlak, no pokazuje slabije rezultate u prognozi relativne vlažnosti. Unatoč tome, model je dao dobre rezultate i uspješno je simulirao meteorološke uvjete koji su doveli do razvoja konvekcije i tuče u svim promatranim slučajevima.

Abstract (english)

In this study, the WRF-HAILCAST model was used with focus on analyzing the cases of early morning hail in the south Adriatic. This area is specific for the fact that hailstorm occur more often in the winter period, but with no afternoon maximum in the diurnal course like it appears for the hailstorms over the continent. Contrary, the early morning maximum stands out in the colder part of the year. Mechanisms that lead to convection are then different than the ones in the continent and more investigation is needed to find the causes of convection in these conditions. The goal of this study is to carry out numerical simulations for a select few cases of winter convection in the southern Adriatic and evaluate the success of the model in simulating hail and the selected meteorological parameters. For this analysis, the study uses synoptic charts and radiosounding profiles from station Zadar - Zemunik. The obtained results where then compared to the measured data from the Croatian Meteorological and Hydrological Service’s network of surface stations. Moreover, the calculated potential of lightning activity (LPI) was compared to the measured data of lightning activity from the LINET network and the study carries out the scale decomposition of the wind flow field using the Barnes filter to obtain better information on the effect of the individual scales in the total wind flow field. The results show that the model underestimates the size of the hail, but overestimates the spatial distribution of the simulated hail. Also, the model predicts the temperature and air pressure data very well, but it shows poor results in predicting the relative humidity data. Despite that, the model gave good results and it successfully simulated the meteorological conditions that led to the development of convection and hail in all observed cases.

• Keywords: Tuča; Južni Jadran
• Keywords (english): Hail; Southern Adriatic
• Language: croatian
• URN:NBN: urn:nbn:hr:217:041311
• Study programme: Title: graduate academic research programme: Master of Physics – geophysics, modules: Seismology and solid Earth physics, Meteorology and physical oceanography; specializations in: Seismology and solid Earth physics, Meteorology and physical oceanography; Course: Meteorology and physical oceanography; Study programme type: university; Study level: graduate; Academic / professional title: sveučilišni magistar fizike – geofizike (sveučilišni magistar fizike – geofizike)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2024-10-04 10:26:50