Bio-climatic classification of Iran by multivariate statistical methods

Abstract

Traditional classification approaches tend to classify climates in terms of one or a few climatic variables given the specific circumstances. However, climate incorporates wide varieties of variables and serves as a cumulative process. In the present research, the number of 197 climatic parameters were selected and evaluated drawing upon data from the Iranian Meteorological Organization at 164 selected stations during the period of 1981 to 2018. After accuracy verification (by statistics of reliable synoptic stations in the area), such parameters were applied to develop a database. Then, upon reviewing of the library documents while considering the effective climatic elements in the formation and distribution of vegetation in different regions of Iran, finally 137 climatic variables were identified, in turn used as input data to perform factor analysis in SPSS software. Such variables greatly affect the climate of each region, and in fact, are determinant factors of the climate in each area. Subsequently, cluster analysis was performed on climatic factors obtained from the factor analysis method. According to the results, throughout the Iran, nine factors of temperature, relative humidity, cold season rainfall, warm-season rainfall, wind speed, semi-cloudy days, thunderstorm and snowy day with eigenvalues greater than one were 29.

Evidence of Zelkova carpinifolia as a potential host of Tuber uncinatum in Hyrcanian temperate forests

“…The ACHTFs surrounded by the mountains along the southern coasts of the Caspian Sea are one of the very rare temperate deciduous forests in the semi-arid region of the Middle East. The studied regions of the HTFs considered humid temperate zone accompanied by high relative humidity based on bio-climatic classi cation (Khatibi & Saberi 2020).…”

Comparative Phylogeography of Tree Species in the Hyrcanian Forests, Iran by Genome-wide SNPs

“…The Hyrcanian region exhibits spatial variations in precipitation and climate, with the Gilan province (West) having higher rainfall and being more humid than the Mazandaran and Golestan provinces (Domroes et al, 1998;Khalili and Rahimi, 2014). The bioclimatic classification of Iran classifies the Hyrcanian region into very humid and humid areas (zones 12 and 15, respectively in Khatibi & Saberi, 2020), with an overlapping zone in the central region (Khatibi and Saberi, 2020). This division results in two precipitation clusters in the Hyrcanian area, with the northwestern section having a mean annual precipitation of 1,331 mm and the eastern section having a mean yearly rainfall of 379 mm (Domroes et al, 1998), which is also reflected in the spatiotemporal distribution map of Iran (Khalili and Rahimi, 2014).…”