Balkan — The Balkans are located in south east Europe. A new data set of high quality daily maximum and minimum summer air temperature series from 246 stations in the eastern Mediterranean region (including Albania, Bosnia-Herzegovina, Bulgaria, Croatia, Cyprus, Greece, Israel, Romania, Serbia, Slovenia, Turkey) has been developed and used to quantify changes in heat length and intensity between 1960 and 2006. Daily temperature analyses suggest that many instrumental measurements in the 1960s are warm biased, correcting for these biases regionally averaged heat wave trends are up to 8% higher.
A heat wave is a prolonged period of excessively hot weather, which may be accompanied by high humidity. There is no universal definition of a heat wave. One of the longest heat waves on record was the one at Marble Bar in Australia, where from October 31, 1923 to April 7, 1924 the temperature broke the 37.8 °C (100.0 °F) benchmark (160 days).
An example of a recent heat wave in the Balkans happened in June 2008. A period of extremely warm temperatures started and lasted three weeks. Temperatures stayed over or around 40 degrees Celsius (104 degrees Fahrenheit).
To make the situation even more difficult for the population, this period was also marked by tropical nights where temperatures stayed above 20 or even 30 degrees Celsius overnight.
In a recent study it was found that there were significant heat wave or temperature changes across the western Balkans, southwestern and western Turkey, and along the southern Black Sea coastline. Since the 1960s, the mean heat wave intensity, heat wave length and heat wave number across the eastern Mediterranean region have increased by about a factor of 7.6, 7.5 and 6.2 respectively. These findings suggest that the heat wave increase in this region is higher than previously reported.