University of Tehran Press Iranian Journal of Soil and Water Research 2008-479X 46 4 2015 12 22 Two Hundred Year Based Tree-ring Reconstruction of Maximum Temperature Koliak, Nowshahr Two Hundred Year Based Tree-ring Reconstruction of Maximum Temperature Koliak, Nowshahr 641 652 56788 10.22059/ijswr.2015.56788 FA Mehdi Nadi PhD Candidate, agro meteorology, University College of Agriculture & Natural Resources University of Tehran, Faculty of Agricultural Engineering & Technology, Department of Irrigation and reclamation, Agro meteorology Division 0000-0003-0854-8380 Javad Bazrafshan Assist. Professor, University College of Agriculture & Natural Resources university of Tehran, Faculty of Agricultural Engineering & Technology, Department of Irrigation and reclamation, Agro meteorology Division Kambiz Pourtahmasi Associate Professor, Wood & Paper Science & Technology Department, University College of Agriculture & Natural Resources, university of Tehran Achim Bräuning Professor, Department of Geography, University of Erlangen-Nuremberg, Germany Journal Article 2015 03 02 One of the ways to reconstruction of climatic variables, especially temperature, is dendroclimatology or the use of tree-ring width chronology. There did not so far exist any tree-ring based reconstruction of long term temperature in Caspian Ecosystem. Throughout the present research, temperature was reconstructed using <em>Fagus Orientalis</em> tree-ring chronology samples collected from high elevated regions of Koliak (Nowshahr). To follow the target, a correlation between annual tree ring width and meteorological variables in local and as well in global scales was considered. Correlation analysis revealed that drop in maximum temperature is a limiting factor of tree growth, particularly in the period March-September. So, the average of March-September maximum temperature (based on data taken from Nowshahr’s station) was reconstructed. The results of temperature reconstruction showed that this region has experienced very cold years more than it has very warm ones within the past two centuries. Also the first decade of 20^th century and years, 1950-1970 vs the decade of 1830^th, and years 1930-1950 formed the warmest vs coldest periods, respectively. Besides, the significant effect of negative NAO on temperature rise in the early months of growth period was revealed. Reconstructed temperatures of this research as like the results obtained by other researchers in Eastern Mediterranean didn’t show any warming trend within recent years. One of the ways to reconstruction of climatic variables, especially temperature, is dendroclimatology or the use of tree-ring width chronology. There did not so far exist any tree-ring based reconstruction of long term temperature in Caspian Ecosystem. Throughout the present research, temperature was reconstructed using <em>Fagus Orientalis</em> tree-ring chronology samples collected from high elevated regions of Koliak (Nowshahr). To follow the target, a correlation between annual tree ring width and meteorological variables in local and as well in global scales was considered. Correlation analysis revealed that drop in maximum temperature is a limiting factor of tree growth, particularly in the period March-September. So, the average of March-September maximum temperature (based on data taken from Nowshahr’s station) was reconstructed. The results of temperature reconstruction showed that this region has experienced very cold years more than it has very warm ones within the past two centuries. Also the first decade of 20^th century and years, 1950-1970 vs the decade of 1830^th, and years 1930-1950 formed the warmest vs coldest periods, respectively. Besides, the significant effect of negative NAO on temperature rise in the early months of growth period was revealed. Reconstructed temperatures of this research as like the results obtained by other researchers in Eastern Mediterranean didn’t show any warming trend within recent years. https://ijswr.ut.ac.ir/article_56788_42c0f5b1c1db73b2b70d0ac9ef242f7f.pdf