2 research outputs found
Changes of Temperature and Precipitation Extremes Following Homogenization = Hőmérsékleti és csapadék szélsőségek vizsgálata homogenizált adatokon
Climate indices to detect changes have been defined in several international projects on climate change. Climate index calculations require at least daily resolution of time series without inhomogeneities, such as transfer of stations, changes in observation practice. In many cases the characteristics of the estimated linear trends, calculated from the original and from the homogenized time series are significantly different. The ECA&D (European Climate Assessment & Dataset) indices and some other special temperature and precipitation indices of own development were applied to the Climate Database of the Hungarian Meteorological Service. Long term daily maximum, minimum and daily mean temperature data series and daily precipitation sums were examined. The climate index calculation processes were tested on original observations and on homogenized daily data for temperature; in the case of precipitation a complementation process was performed to fill in the gaps of missing data. Experiences of comparing the climate index calculation results, based on original and complemented-homogenized data, are reported in this paper. We present the preliminary result of climate index calculations also on gridded (interpolated) daily data.
A klĂmaváltozás detektálása cĂ©ljábĂłl több nemzetközi, a klĂmaváltozással foglalkozĂł programban klĂmaindexek sorát definiáltak. Az Ă©ghajlati szĂ©lsĹ‘sĂ©gek vizsgálatához, avagy az extrĂ©m indexek számĂtásához inhomogenitásoktĂłl (állomás áttelepĂtĂ©sek, a mĂ©rĂ©si idĹ‘pontok Ă©s a mĂ©rĂ©si mĂłdszerek változásai) mentes, jĂł minĹ‘sĂ©gű napi adatsorok szĂĽksĂ©gesek. Sok esetben ugyanis jelentĹ‘sen eltĂ©r az eredeti Ă©s a homogenizált adatok alapján számolt lineáris trend Ă©rtĂ©ke nemcsak nagyságában, hanem elĹ‘jelĂ©ben is. Ez pedig a klĂmaváltozás tekintetĂ©ben tĂ©ves következtetĂ©sek levonásához vezethet. Az OMSZ klimatolĂłgiai adatbázisban törtĂ©nt fejlesztĂ©s során megvalĂłsĂtottuk az ECA&D (European Climate Assessment & Dataset) projektben alkalmazott extrĂ©m klĂmaindexek sorozatát Ă©s ezeket kiegĂ©szĂtettĂĽk nĂ©hány általunk kifejlesztett karakterisztikával. Az extrĂ©mumokban fellĂ©pĹ‘ változások nyomon követĂ©sĂ©re lineáris trendelemzĂ©st vĂ©geztĂĽnk mind az eredeti, mind a homogenizált sorokon, ennek a vizsgálatnak a tapasztalatairĂłl számolunk be ebben a dolgozatban. Bemutatjuk emellett a rácsponti klĂmaindex számĂtások elĹ‘zetes eredmĂ©nyeit is
Changes of Temperature and Precipitation Extremes following Homogenization
Climate indices to detect changes have been defined in several international projects on climate change. Climate index calculations require at least daily resolution of time series without inhomogeneities, such as transfer of stations, changes in observation practice. In many cases the characteristics of the estimated linear trends, calculated from the original and from the homogenized time series are significantly different. The ECA&D (European Climate Assessment & Dataset) indices and some other special temperature and precipitation indices of own development were applied to the Climate Database of the Hungarian Meteorological Service. Long term daily maximum, minimum and daily mean temperature data series and daily precipitation sums were examined. The climate index calculation processes were tested on original observations and on homogenized daily data for temperature; in the case of precipitation a complementation process was performed to fill in the gaps of missing data. Experiences of comparing the climate index calculation results, based on original and complemented-homogenized data, are reported in this paper. We present the preliminary result of climate index calculations also on gridded (interpolated) daily data