Temperature variability in Serbia in the second half of the 20th century

Abstract

According to data of IPCC (Intergovernmental Panel for Climatic Change), the global surface air temperature increased to 0,6 ± 0,2 °C in the 20th century. Weber G. R., (1995) quotes that there is a trend of cold in the last 60 years in the middle latitudes including Europe, too. Starting from already mentioned perplexities we have tried to perceive the problem of climate variability in Serbia in the second half of the 20th century, when it came to very important increasing of concentration of CO2. With that aim we observed the decade values of average annual temperatures in the network of 20 climatic stations. In the period 1951 - 1990 a decrease of temperature was registered in 13 stations while in other stations an increase was less than 0,1 °C. Explorers from Bulgaria (Alexandrov V., 2000) and Hungary (Domonkos P., Zoboki J., 2000) came to similar results, too. However, if we take in account the last decade 20th century the number of stations with positive changes is enlarged on 15. Stations that have small changes and those with decrease of temperature were localized in the south and south eastern part of the country, and they are mainly coincided with before separated climatic regions with maritime pluviometric regime (Radovanović M., 2001). Using Dzerdzevskis B. L., (1975) division on three main types of circulation in the north hemisphere, we found that the increase of temperatures in the last decade 20th century is above all caused by change of dominant type of circulation from the south meridian to zonal. An analysis of seasonal changes showed that in the last five decades 20th century it came to decrease of winter temperatures in almost half of the stations in contrast with results of paleoclimatics models of possible greenhouse effect.

Prema podacima IPCC (Međuvladin panel za klimatske promene) globalna temperatura vazduha na Zemlji, porasla je za 0,6±0,2 °C u XX veku. Međutim Veber (Weber G. R., 1995) navodi da je u poslednjih 60 godina osmotren trend zahlađenja, na srednjim geografskim širinama, uključujući i Evropu. Polazeći od ovih kontradiktornosti, pokušali smo da sagledamo kolebanja temperature vazduha u Srbiji u drugoj polovini XX veka, kada je inače došlo do značajnog povećanja koncentracije CO2. S tim ciljem, posmatrane su dekadne vrednosti srednjih godišnjih temperatura vazduha u mreži od 20 stanica, u periodu 1951 - 1990. g. Pad temperature je registrovan na 13 stanica dok je na ostalim porast manji od 0,1 °C. Istraživači iz Bugarske, Aleksandrov (Alexandrov V. 2000) i Mađarske Domonkos i Zoboki (Domonkos P., Zoboki J., 2000) su takođe došli do sličnih rezultata. Međutim, ako uzmemo u obzir poslednju dekadu XX veka, broj stanica sa pozitivnim promenama se povećava na 15. Stanice koje imaju male promene i one sa padom temperature, nalaze se u južnom i jugoistočnom delu zemlje i ta oblast se u osnovi nadovezuje na već izdvojeni klimatski region sa maritimnim režimom padavina (Radovanović M., 2001). Koristeći podelu koju je dao Dzerdzevskij (Dzerdzevskij B. L., 1975), na 3 glavna tipa na severnoj hemisferi, utvrdili smo da je porast temperature u poslednjoj dekadi XX veka, pre svega izazvan promenom dominantnih tipova cirkulacije, od meridionalno južnog ka zonalnom. Analiza sezonskih promena je pokazala da je u poslednjih 5 dekada XX veka došlo do pada zimskih temperatura na gotovo polovini stanica, suprotno rezultatima paleoklimatskih modela, koji ukazuju na mogući efekat staklene bašte.