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Klimatske promjene predstavljaju sve veći problem u suvremenom svijetu, a njihov utjecaj na urbane sredine iznimno je važan s mnogih aspekata (npr. ekološkog, socijalnog, ekonomskog, zdravstvenog). Više od polovice svjetske populacije živi u gradovima koji doprinose emisiji stakleničkih plinova, a time i klimatskim promjenama. S druge strane, stanovništvo gradova je pod utjecajem klimatskih uvjeta koji čine urbanu klimu. Gradovi pokazuju specifične meteorološke i klimatološke karakteristike zbog čega se sve više proučava urbana klima. U ovom radu napravljena je analiza temperaturnih obilježja i toplinskog opterećenja grada Dubrovnika na temelju izmjerenih podataka o temperaturi u razdoblju 1961.-2019. na meteorološkoj postaji Dubrovnik te na temelju satelitskih snimaka satelita LANDSAT5 i analize klimatskih indeksa dobivenih simulacijama modela MUKLIMO_3. U radu su proučavani trendovi srednjih dnevnih, maksimalnih dnevnih, minimalnih dnevnih i sezonskih temperatura pomoću dvije nezavisne metode, Mann-Kendall testa i metode linearne regresije. Rezultati pokazuju uzlazan trend za sve promatrane temperature. Istim metodama ispitani su i trendovi klimatskih indeksa (studeni dani, ljetni dani, tropske noći) koji su u skladu s pozitivnim temperaturnim trendom i također ukazuju na povećanje toplinskog opterećenja grada Dubrovnika u promatranom razdoblju. Prema Köppenovoj klasifikaciji klime pokazano je da u 30-godišnjim razdobljima za godine 1961.-1990. nije došlo do promjene tipa klime u Dubrovniku te da prevladava sredozemna klima sa suhim i vrućim ljetom (Csa). Rezultati satelitskih snimaka prosječnih ljetnih površinskih temperatura u razdoblju 2001.-2010. pokazuju da se urbanizirane površine više zagrijavaju od prirodnih površina s vegetacijom. Rezultati klimatskih indeksa (ljetni i vrući dani, tople i ljetne večeri, tople i tropske noći) dobiveni simulacijama modela MUKLIMO_3 također pokazuju da se urbanizirane površine više zagrijavaju od prirodnih površina te da to zagrijavanje ovisi o gustoći izgrađenosti. In modern world problem of climate change is raising. More than half of world's population is living in cities, which contribute green house gass emission causing global climate changes. Urban areas show particulary meteorological and climatological characteristics, that's why urban climate is getting more considered. In this work temperature characteristics and heat load of Dubrovnik is analyzed by using observed temperature data from local station in Dubrovnik in period 1961.-2019., satellite data from LANDSAT5 satellite were also used for analysis and analysis of climate indices obtained from simulations of MUKLIMO_3 model. Trends of mean daily, maximum daily, minimum daily and seasonal temperatures were analyzed using two independent methods, Mann-Kendall test and method of linear regression. Results are showing positive trends for all analyzed temperatures. Using same methods, trends of climate indices (frost days, summer days and tropical nights) were also analyzed and have showed raise of temperature and heat load in the city of Dubrovnik in the observed period. Analysis of Köppen climate clasification showed that in Dubrovnik there were no changes of climate type in 30-year periods for years in 1961.-1990., climate type of Dubrovnik is hot-summer Mediterranean climate. Results of satellite data of mean summer land surface temperatures in period 2001.-2010. showed that urban surfaces are heated more than natural surfaces with vegetation. Results of climate indices (summer and hot days, warm and summer evenings, warm and tropical nights) obtained by simulations of MUKLIMO_3 model also showed that urban surfaces are heated more than natural surfaces with vegetation and less dense built areas.

U članku su analizirani nizovi srednjih dnevnih, mjesečnih i godišnjih temperatura zraka i mjesečnih i godišnjih oborina mjereni na tri postaje na otoku Visu. Korišteni su podaci opaženi na glavnoj meteorološkoj postaji Komiža (1956.-2019.) i automatskim postajama Hum (2012.-2019.) i Dračevo polje (2017.-2019.). Osim toga analizirani su i nizovi srednjih dnevnih, mjesečnih i godišnjih temperatura površine mora mjereni na postaji Komiža (1991.-2019.). Vis je mali karbonatni otok površine 89,72 km2 s najvišim vrhom od 587 mnm na kojem je locirana automatska meteorološka postaja Hum. Režim temperatura zraka na sve tri postaje na malom otoku udaljenom od kopna je sličan. Srednje dnevne, mjesečne i godišnje temperature zraka najviše su na postaji Komiža. Više su za oko 1 ºC od srednjih godišnjih temperatura zraka izmjerenih u Dračevom polju i oko 3,6 ºC od onih izmjerenih na postaji Hum. Trend porasta srednjih mjesečnih temperatura zraka u razdoblju 1964.-2019. javlja se u svakom pojedinom mjesecu godine. Gradijent opadanja srednjih dnevnih temperatura zraka s nadmorskom visinom u toplom dijelu godine znatno je niži nego u hladnom dijelu godine. Najintenzivniji porasti temperatura zraka javljaju se u najtoplijem dijelu godine. Srednje godišnje vrijednosti temperatura površine mora u razdoblju 1991.-2019. brže su rasle od srednjih godišnjih temperatura zraka. Prosječne mjesečne temperature površine mora više su od prosječnih mjesečnih temperatura zraka u razdoblju od rujna do travnja. U ostalim mjesecima su niže. Minimalne dnevne temperature zraka javljaju se u hladnom dijelu godine između 6 i 7 sati dok se tijekom toplog dijela godine javljaju nešto ranije između 4 i 5 sati. Maksimalne dnevne temperature zraka uglavnom se javljaju oko 13 sati. Niti jedan od analiziranih nizova godišnjih i mjesečnih oborina u razmatranom razdoblju (1956.-2019.) nije pokazao postojanje statistički značajnog trenda porasta ili opadanja., The paper analyses the series of average daily, monthly and annual air temperatures and monthly and annual precipitation measured at three stations on Vis Island. The used data were observed at the main meteorological station Komiža (1956 - 2019), as well as automatic stations Hum (2012 – 2019) and Dračevo polje (2017 - 2019). Additionally, the analysis also included the series of average daily, monthly and annual sea surface temperatures measured at the station Komiža (1991 - 2019). Vis Island is a small carbonate island with a surface of 89.72 km2 and the highest peak of 587 asl, where the automatic meteorological station Hum is located. The air temperature regimes at all three stations on the small island far off the mainland are similar, with the average daily, monthly and annual air temperatures being the highest at the station Komiža - by about 1 ºC higher than the average annual air temperatures measured at Dračevo polje and by about 3.6 ºC higher than those measured at the station Hum. The upward trend in average monthly air temperatures in the period of 1964 - 2019 occurs in each individual month of the year. The gradient of average daily air temperatures’ decrease with altitude is significantly lower in the warm part of the year than in the cold one. The most intense increases in air temperatures occur in the warmest part of the year. The average annual values of sea surface temperatures in the period of 1991 – 2019 increased faster than the average annual air temperatures. The average monthly sea surface temperatures are higher than the average monthly air temperatures in the period from September to April, while lower in other months. The minimum daily air temperatures occur in the cold part of the year between 6 a.m. and 7 a.m. During the warm part of the year they occur slightly earlier - between 4 a.m. and 5 a.m. The maximum daily air temperatures generally occur around 1 p.m. Not one of the analysed series of annual and monthly precipitation in the observed period (1956 - 2019) showed the existence of a statistically significant upward or downward trend., Im Beitrag werden die Zeitreihen für die Tages-, Monats- und Jahresmittel der Lufttemperatur sowie für die Monats- und Jahresmittel des Niederschlags analysiert, die an drei Stationen auf der Insel Vis gemessen wurden: an der meteorologischen Hauptstation Komiža (1956-2019) sowie an den automatischen Wetterstationen Hum (2012-2019) und Dračevo polje (2017-2019). Außerdem werden die an der Station Komiža (1991-2019) gemessenen Zeitreihen für die Tages-, Monats- und Jahresmittel der Meeresoberflächentemperatur analysiert. Vis ist eine kleine Kalkinsel mit einer Fläche von 89,72 Quadratkilometern und mit dem höchsten Gipfel von 587 Metern über dem Meeresspiegel, wo sich die automatische Wetterstation Hum befindet. Das Lufttemperaturregime an allen drei Stationen auf dieser weit vom Land entfernten Insel ist ähnlich. Die höchsten mittleren Tages-, Monats- und Jahreslufttemperaturen wurden an der Station Komiža gemessen. Sie sind etwa 1 ºC höher als die an Dračevo polje gemessenen mittleren Jahreslufttemperaturen und etwa 3,6 ºC höher als die an der Station Hum gemessenen mittleren Jahreslufttemperaturen. Ein Aufwärtstrend liegt bei den mittleren Monatslufttemperaturen im Zeitraum 1964-2019 in jedem einzelnen Monat des Jahres vor. Der abfallende Gradient der mittleren Tageslufttemperaturen ist in der warmen Jahreszeit mit abfallender Seehöhe wesentlich niedriger als in der kalten Jahreszeit. Die stärksten Lufttemperaturerhöhungen wurden in der wärmsten Jahreszeit beobachtet. Die Werte der mittleren Jahresmeeresoberflächentemperaturen erhöhten sich im Zeitraum 1991-2019 schneller als die Werte der mittleren Jahreslufttemperaturen. Die Monatsmittel der Meeresoberflächentemperatur sind höher als die Monatsmittel der Lufttemperatur im Zeitraum zwischen September und April, während sie in anderen Monaten niedriger sind. Die minimalen Tageslufttemperaturen wurden in der kalten Jahreszeit zwischen 6 und 7 Uhr beobachtet, während sie während der warmen Jahreszeit etwas früher, zwischen 4 und 5 Uhr, die Minimalwerte erreichen. Die Maximalwerte der Tageslufttemperatur zeigen sich meistens um 13 Uhr. Bei keinen von den analysierten Zeitreihen des Jahres- und Monatsniederschlags zeigte sich im beobachteten Zeitraum (1956-2019) ein statistisch signifikanter Aufwärts- oder Abwärtstrend.

This work calculates and analyses monthly, seasonal and annual precipitation trends over continental Spain between 1961 and 2010, according to data from 144 weather stations widely distributed throughout the study area. The magnitude and sign of the trends were evaluated with Sen¿s slope estimator and their statistical significances were determined with the nonparametric MannKendall test. In general terms, the rainfall trends for the period and the study area are mainly non nonsignificant at the monthly, seasonal and annual timescales. By and large, we noted the highest number of weather stations with positive significant trends in September and October, whereas the highest number of stations with negative significant trends was observed in February, June, winter, summer and at the annual time¬scale. The most pronounced decreases occurred in June (¿18.58 mm/50years) and in summer (27.67 mm/50years) in the south, which points to an intensification of mediterraneity in this area. We observed a sign asymmetry in significant rainfall trends during winter, spring and at the annual timescales between the north (negative) and the southeast (positive).