Hrvatske vode, Vol. 25 No. 101, 2017.
Professional paper
A comparison of the mean value of air temperature (on different time scales) calculated by two different methods
Ognjen Bonacci
orcid.org/0000-0002-7123-3421
; Faculty of Civil Engineering, Architecture and Geodesy, University of Split, Split, Croatia
Tanja Roje-Bonacci
orcid.org/0000-0002-7123-3421
; Faculty of Civil Engineering, Architecture and Geodesy, University of Split, Split, Croatia
Ivana Željković
; Independent researcher
Abstract
The formula used for the determination of accurate mean daily air temperature, T0, is: T0=(sum(Ti)/24). In the climatological practice in Croatia as well as numerous Central European countries, mean daily air temperature, T1, is calculated by using the following formula (called “official” further in the text): T1=(T7+T14+2*T21)/4. These two formulas result in different values of mean daily, monthly and annual air temperatures. In the paper we have compared mean daily, monthly and annual air temperatures measured at the meteorological stations Zagreb-Grič and Dubrovnik in the period from 1 January 1999 to 31 December 2014 and calculated by applying both formulas. The differences between the ranges of the accurate and official values of mean daily air temperatures at Zagreb-Grič and Dubrovnik stations were analyzed. Additionally, the differences between the accurate mean daily, monthly and annual values of air temperatures, T0, measured at the meteorological stations Dubrovnik and Zagreb-Grič were also calculated and analyzed. It was determined that the accurate mean monthly and annual air temperatures, T0, at the meteorological station Dubrovnik were always higher than those calculated by using the “official” formula (2), whereas at the meteorological station Zagreb-Grič they were always lower. When the temporal scale is extended, the values of these differences are smaller, although still not negligible. The paper was written with the aim of attracting attention to the necessity of studying these issues in the near future.
Keywords
mean daily, monthly and annual air temperature; difference between accurate and official air temperatures; Zagreb-Grič; Dubrovnik
Hrčak ID:
186170
URI
Publication date:
5.9.2017.
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