Vorschlag einer neuen Methode zur Analyse der Trockenheit

Ključan čimbenik pojave i intenziteta suše u svakom okolišu je manja količina oborina od prosječne. Uz to, na fenomen suše snažan utjecaj vrši i temperatura zraka. Što je ona viša od prosječne vrijednosti u određenom dijelu godine, to su i negativne posljedice suše teže. U doba recentne globalne promjene klime koja se najizrazitije manifestira upravo porastom temperature zraka, taj je ključni klimatološki parametar neophodno uvesti u proračun indeksa suše. Uvođenjem tog parametra uz parametar oborine, moguće je definirati integralni indeks suše primjenjiv za analizu bilo koje vrste suša. U članku je prikazana nova metoda analize suše u kojoj se koriste standardizirane vrijednosti oborine i srednje temperature zraka u određenom razdoblju. Standardizirana vrijednost izračunava se tako da se od svake pojedine izmjerene vrijednosti oborine i temperature u nekom vremenskom intervalu (mjesec, sezona, godina, itd.) odbije njena prosječna vrijednost u razmatranom razdoblju te se ta veličina podijeli sa standardnom devijacijom u tom intervalu. Novi Indeks Suše (NIS) izračuna se tako da se od standardizirane vrijednosti oborine odbije standardizirana vrijednost temperature. Vrijednosti NIS-a analizirane su za nizove mjesečnih i godišnjih količina oborine i srednje mjesečne i srednje godišnje temperature zraka izmjerenih na postajama Split-Marjan i Zagreb-Grič u razdoblju 1948. - 2020. Izračunate vrijednosti NIS-ova ukazuju na to da se opasnost od suše značajno intenzivira u posljednjim desetljećima, što se može povezati s učinkom aktualnog globalnog agrijavanja. Na razini mjeseci, sušom su najugroženiji oni u toplom dijelu godine, od travnja do kolovoza u Zagrebu te od lipnja do kolovoza u Splitu.The key factor in drought occurrence and intensity in any environment are quantities of precipitationthat are lower than the average. Additionally, drought phenomenon is stronglyaffected by air temperature - the higher it is than the average temperature value in a certain period of the year, the more severe are the adverse consequences of drought.In this period of climate change,whose most pronounced manifestation is increased air temperature, this key climatological parameter should be, indeed, included in the calculation of drought index. If included, it can, combined with precipitation, determine the integrated drought index that is applicable to analyses of any kind of drought. The paper presents a newdrought analysis method using standardised values of precipitation and mean air temperature in a certain period. The standardised value is calculated by subtracting the average valuein the observed periodfrom each individual measured value of precipitation and temperature in a time interval (month, season, year, etc.), and then dividing this value with the standard deviation in that interval. The new drought index (NDI) is calculated by subtracting the value ofstandardised temperature from the value of standardised precipitation. The NDI values were analysed for series of monthly and annual precipitation quantities and mean monthly and annual air temperatures measured at the stations Split-Marjan and Zagreb-Grič in the 1948-2020 period. The calculated NDI values indicate that drought hazard has been significantly intensifying in the past decades, which can be linked to the effects of global warming. The months most affected by droughts are those in the warm part of the year, i.e. from April to August in Zagreb and from June to August in Split.Der Schlüsselfaktor des Auftretens und der Intensität der Trockenzeit in jeder Umgebung ist die unterdurchschnittliche Niederschlagsmenge. Zusätzlich übt die Lufttemperatur einen starken Einfluss auf die Trockenheit aus. Je höher die Lufttemperatur in Bezug auf den Mittelwert einer bestimmten Jahreszeit, desto schwerwiegender die negativen Folgen. Zur Zeit des globalen Klimawandels, der sich insbesondere im Anstieg der Lufttemperatur manifestiert, soll dieser klimatologischeSchlüsselparameter in die Berechnung des Trockenheitsindex mit der Niederschlagsmengeeinbezogen werden. Auf diese Weise ist es möglich den integralen Trockenheitsindex zu bestimmen, der für die Analyse aller Trockenheitstypen anwendbar ist. Im Beitrag wird eine neue Methode zur Analyse der Trockenheit dargestellt, in der standardisierte Werte des Niederschlags und der mittleren Lufttemperatur in einem bestimmten Zeitraum verwendet werden. Standardisierter Wert wird so berechnet, dass von jedem einzelnen gemessenen Wert des Niederschlags und der Temperatur in einem Zeitraum (Monat, Jahreszeit, Jahr usw.) sein durchschnittlicher Wert in diesem Zeitraum abgezogen wird und diese Größe durch die Standardabweichung in diesem Zeitraum geteilt wird. Der neue Trockenheitsindex wird dann so berechnet, dass vom standardisierten Niederschlagswert der standardisierte Temperaturwert abgezogen wird. Die Werte des neuen Trockenheitsindex wurden für die Zeitreihen von monatlichen und jährlichen Niederschlagsmengen sowie für diemittleren Monatsund Jahreslufttemperaturen analysiert, die an den Stationen Split-Marjan und Zagreb-Grič im Zeitraum 1948-2020 gemessen wurden. Die berechneten Werte des neuen Trockenheitsindex weisen darauf hin, dass die Gefahr der Trockenheit namentlich in den letzten Jahrzeiten zunimmt, was mit den Auswirkungen der globalen Erwärmung verbunden werden kann. Die durch Trockenheit am stärkstenbedrohten Monate sind die Monate in der warmen Jahreszeit und zwar von April bis August in Zagreb und von Juni bis August in Split

Vorschlag einer neuen Methode zur Analyse der Trockenheit

Ključan čimbenik pojave i intenziteta suše u svakom okolišu je manja količina oborina od prosječne. Uz to, na fenomen suše snažan utjecaj vrši i temperatura zraka. Što je ona viša od prosječne vrijednosti u određenom dijelu godine, to su i negativne posljedice suše teže. U doba recentne globalne promjene klime koja se najizrazitije manifestira upravo porastom temperature zraka, taj je ključni klimatološki parametar neophodno uvesti u proračun indeksa suše. Uvođenjem tog parametra uz parametar oborine, moguće je definirati integralni indeks suše primjenjiv za analizu bilo koje vrste suša. U članku je prikazana nova metoda analize suše u kojoj se koriste standardizirane vrijednosti oborine i srednje temperature zraka u određenom razdoblju. Standardizirana vrijednost izračunava se tako da se od svake pojedine izmjerene vrijednosti oborine i temperature u nekom vremenskom intervalu (mjesec, sezona, godina, itd.) odbije njena prosječna vrijednost u razmatranom razdoblju te se ta veličina podijeli sa standardnom devijacijom u tom intervalu. Novi Indeks Suše (NIS) izračuna se tako da se od standardizirane vrijednosti oborine odbije standardizirana vrijednost temperature. Vrijednosti NIS-a analizirane su za nizove mjesečnih i godišnjih količina oborine i srednje mjesečne i srednje godišnje temperature zraka izmjerenih na postajama Split-Marjan i Zagreb-Grič u razdoblju 1948. - 2020. Izračunate vrijednosti NIS-ova ukazuju na to da se opasnost od suše značajno intenzivira u posljednjim desetljećima, što se može povezati s učinkom aktualnog globalnog agrijavanja. Na razini mjeseci, sušom su najugroženiji oni u toplom dijelu godine, od travnja do kolovoza u Zagrebu te od lipnja do kolovoza u Splitu.The key factor in drought occurrence and intensity in any environment are quantities of precipitationthat are lower than the average. Additionally, drought phenomenon is stronglyaffected by air temperature - the higher it is than the average temperature value in a certain period of the year, the more severe are the adverse consequences of drought.In this period of climate change,whose most pronounced manifestation is increased air temperature, this key climatological parameter should be, indeed, included in the calculation of drought index. If included, it can, combined with precipitation, determine the integrated drought index that is applicable to analyses of any kind of drought. The paper presents a newdrought analysis method using standardised values of precipitation and mean air temperature in a certain period. The standardised value is calculated by subtracting the average valuein the observed periodfrom each individual measured value of precipitation and temperature in a time interval (month, season, year, etc.), and then dividing this value with the standard deviation in that interval. The new drought index (NDI) is calculated by subtracting the value ofstandardised temperature from the value of standardised precipitation. The NDI values were analysed for series of monthly and annual precipitation quantities and mean monthly and annual air temperatures measured at the stations Split-Marjan and Zagreb-Grič in the 1948-2020 period. The calculated NDI values indicate that drought hazard has been significantly intensifying in the past decades, which can be linked to the effects of global warming. The months most affected by droughts are those in the warm part of the year, i.e. from April to August in Zagreb and from June to August in Split.Der Schlüsselfaktor des Auftretens und der Intensität der Trockenzeit in jeder Umgebung ist die unterdurchschnittliche Niederschlagsmenge. Zusätzlich übt die Lufttemperatur einen starken Einfluss auf die Trockenheit aus. Je höher die Lufttemperatur in Bezug auf den Mittelwert einer bestimmten Jahreszeit, desto schwerwiegender die negativen Folgen. Zur Zeit des globalen Klimawandels, der sich insbesondere im Anstieg der Lufttemperatur manifestiert, soll dieser klimatologischeSchlüsselparameter in die Berechnung des Trockenheitsindex mit der Niederschlagsmengeeinbezogen werden. Auf diese Weise ist es möglich den integralen Trockenheitsindex zu bestimmen, der für die Analyse aller Trockenheitstypen anwendbar ist. Im Beitrag wird eine neue Methode zur Analyse der Trockenheit dargestellt, in der standardisierte Werte des Niederschlags und der mittleren Lufttemperatur in einem bestimmten Zeitraum verwendet werden. Standardisierter Wert wird so berechnet, dass von jedem einzelnen gemessenen Wert des Niederschlags und der Temperatur in einem Zeitraum (Monat, Jahreszeit, Jahr usw.) sein durchschnittlicher Wert in diesem Zeitraum abgezogen wird und diese Größe durch die Standardabweichung in diesem Zeitraum geteilt wird. Der neue Trockenheitsindex wird dann so berechnet, dass vom standardisierten Niederschlagswert der standardisierte Temperaturwert abgezogen wird. Die Werte des neuen Trockenheitsindex wurden für die Zeitreihen von monatlichen und jährlichen Niederschlagsmengen sowie für diemittleren Monatsund Jahreslufttemperaturen analysiert, die an den Stationen Split-Marjan und Zagreb-Grič im Zeitraum 1948-2020 gemessen wurden. Die berechneten Werte des neuen Trockenheitsindex weisen darauf hin, dass die Gefahr der Trockenheit namentlich in den letzten Jahrzeiten zunimmt, was mit den Auswirkungen der globalen Erwärmung verbunden werden kann. Die durch Trockenheit am stärkstenbedrohten Monate sind die Monate in der warmen Jahreszeit und zwar von April bis August in Zagreb und von Juni bis August in Split

Relationship between the sea surface and surface air temperature: a case of the Island of Hvar (Adriatic Sea, Croatia)

Povezanost površinske temperature mora (PTM) i površinske temperature zraka (PTZ) izmjerene na malome otoku Hvaru (Jadransko more) ispituju se na godišnjim i mjesečnim vremenskim ljestvicama, koristeći se podacima za razdoblje od pedeset pet godina (1964. – 2018.). Analizirana su sljedeća tri indeksa PTM-a i PTZ-a: (1) apsolutni minimum, (2) srednja vrijednost, (3) apsolutni maksimum. Rezultati su istaknuli statistički značajan trend porasta za sva tri godišnja indeksa PTM-a. U slučaju PTZ-a trend niza apsolutnih minimalnih godišnjih vrijednosti nije statistički značajan. Za nizove srednjih i apsolutno maksimalnih godišnjih vrijednosti PTZ-a trend je statistički značajan na razini p < 0,01. Mjesečne analize indeksa PTM-a gotovo u svim mjesecima (osim u listopadu) imaju statistički značajne trendove povećanja. U slučaju PTZ-a, statistički značajan trend porasta svih analiziranih indeksa dogodio se preko ljeta (srpanj i kolovoz). Rezultati pokazuju da je analizirana regija, posebice mali jadranski otoci, ugrožena klimatskim promjenama, tj. globalnim zatopljenjem tijekom ljeta. Primjenom RAPS metode na minimalnom godišnjem PTM-u zabilježen je statistički značajni pomak 1988. godine. Deset godina poslije, 1998. godine, otkriven je statistički značajan pomak prema gore na srednjem i maksimalnom indeksu PTM-a i PTZ-a. U slučaju minimalnih godišnjih vrijednosti PTZ-a otkriven je statistički značajan pomak prema dolje, počevši od 1979. godine. U analiziranom slučaju otoka Hvara, zagrijavanje indeksa PTM-a veće je od zagrijavanje indeksa PTZ-a i događa se tijekom cijele godine (osim u listopadu).Relationship of Sea Surface Temperature (SST) and Surface Air Temperature (SAT) measured at the small island of Hvar (Adriatic Sea) are examined on annual and monthly time scales using data for a period of 55 years (1964-2018). The following three SST and SAT indices were analysed: (1) absolute minimum; (2) mean; (3) absolute maximum. The results highlighted a statistically significant increasing trend for all three SST analysed annual indices. In the case of SAT absolute minimum increasing trend is not statistically significant. For the other two indices the trends are statistically significant at the level, p<0.01. Monthly analysis for SST indices almost in all months (except October) have statistically significant increasing trends. In the case of SAT, a statistically significant increasing trend for all analysed indices occurred in summer (July and August). All results point out that the analysed region, especially small Adriatic islands are endangered of climate change, i.e. global warming during the summertime. Using the RAPS method on the minimum annual SST, a statistically significant shift upward was detected in 1988. Ten years later, in 1998, a statistically significant shift upward was detected on the mean and maximum SST and SAT indices. In the case of SAT minimum annual values, a statistically significant shift downward is detected, starting in 1979. In the analysed case of the Island of Hvar, the warming of SST indices is higher than the warming of SAT indices and occur during the whole year (except in October)

Die Analyse der Beziehungen zwischen Lufttemperatur, Meeresoberflächentemperatur und Niederschlag auf der Insel Vis

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

Die Analyse der Beziehungen zwischen Lufttemperatur, Meeresoberflächentemperatur und Niederschlag auf der Insel Vis

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

Analytic pulse design for selective population transfer in many-level quantum systems: maximizing amplitude of population oscillations

State selective preparation and manipulation of discrete-level quantum systems such as atoms, molecules or quantum dots is a the ultimate tool for many diverse fields such as laser control of chemical reactions, atom optics, high-precision metrology and quantum computing. Rabi oscillations are one of the simplest, yet potentially quite useful mechanisms for achieving such manipulation. Rabi theory establishes that in the two-level systems resonant drive leads to the periodic and complete population oscillations between the two system levels. In this paper an analytic optimization algorithm for producing Rabi-like oscillations in the general discrete many-level quantum systems is presented.Comment: Published in Phys.Rev.A. This is the final published versio

Quantifying and comparing web news portals’ article salience using the VoxPopuli tool

[EN] VoxPopuli tool enables quantification of absolute and relative salience of news articles published on daily news web portals. Obtained numerical values for the two types of salience enable direct comparison of audience impact of different news articles in specified time period. Absolute salience of a news article in a specified time period is determined as the total number of distinct readers who commented on the story in that period. Hence, articlesthat appear on web portals with larger audiences will in general be (absolutely) more salient as there are more potential commentators to comment on them. On the other hand, relative salience of a particular article during a particular time period is calculated as the quotient of a number of distinct readers who comented on that particular story and the number of all readers who in the same period commented on any news story published on the same news portal. As such relative salience will always be a number between 0 and 1, irrespective of the popularity of particular news portal, the (relative) salience of news stories on different news portals can be compared.Bonacci, D.; Jelinić, A.; Jurišić, J.; Vesnić-Alujević, L. (2016). Quantifying and comparing web news portals’ article salience using the VoxPopuli tool. En CARMA 2016: 1st International Conference on Advanced Research Methods in Analytics. Editorial Universitat Politècnica de València. 31-37. https://doi.org/10.4995/CARMA2016.2015.3137OCS313