Content area
Full Text
ABSTRACT
Last decades of the 20th and the first of the 21st century were marked by rising awareness of climate change. A load of studies clearly shows an increase of the global average temperature, and changes in internannual distribution of rainfall in Southern Europe. The impact of these quantitative findings on climate acquire qualitative expression by applying climatic classifications.
South Bulgaria is located in the transition zone between Continental and Mediterranean climate. Despite the relatively small size of the area, and due to its diverse terrain, the territory belongs to the different sub-regions according to Köppen climate classification.
For the study purposes meteorological data from 50 meteorological stations located at various altitudes were used. Data covers the period 1961-2010 year. Man-Kendall trend test was applied. Climatic zoning of territory was done utilizing Köppen classification for two most distant periods (1961-1990 and 1981-2010). Analysis of the differences found were also done
Keywords: Koppen, climate, classification, climate change, drought, Bulgaria
INTRODUCTION
Last decades of the 20th and the first of the 21st century were marked by rising awareness of climate change. A load of studies clearly shows an increase of the global average temperature, and changes in internannual distribution of rainfall in Southern Europe.
Long-term annual average air temperature over Bulgaria during the 20th century is not marked by any significant trend. This result differs from globally stated increase in average surface air temperature. The above findings confirm observed tendencies in local, regional and global scale could differs significantly [1].
In the last two decades, all countries in the Balkan region are affected of drought. Drought is a natural part of climatic cycle in Bulgaria. The frequency of dry years in Trace Lowland increases, but the frequency of wet ones does not show any trend [2].
Statistically significant decreasing trend was observed in snow depth as well as in number of days with snow cover for the mountain regions of South Bulgaria [3]
Three and more consecutive days with temperature above 38 C were registered after the year 1985 and 70% of registered...