It is obvious that climate in Bulgaria in recent decades has been changing. The hot summer days are getting more and the ski season seems to be getting shorter. But what is the reason for the changes, according to experts?

"Climate is not something static.It evolves. According to what is known to science, there are fluctuationsand different periods in the development of climate, which is something natural," says in an interview for Radio Bulgaria Assoc. Prof. Ilian Gospodinov from the National Institute of Meteorology and Hydrology at the Bulgarian Academy of Sciences. Actually, in the first half of the twentieth century, the climate in this country was relatively warmer. In the middle of the century a long period of cold weather was observed, while the weather became warmer again in the last years of the twentieth century. These are deviations in the range of 1-2 degrees Celsius averagely for the whole country. This is largely due to natural climate changes, says Assoc. Prof. Ilian Gospodinov. "You know that in earlier times there were even more dramatic variations in climate, such as ice ages," he adds. Of course, the relative warming as a whole in the world and in Bulgaria in particular in the second half of the twentieth century and today is also a result of the impact of human activity on the climate system. The warmest years in Bulgaria, since the start of meteorological studies at the end of the XVII century, have been the past 20 years, the expert says.

Rapid development of economic activity can lead to irreversible climate changes to which people will have to adapt. According to forecasts, in the coming decades, warm weather will be more frequent and cold periods will be less likely in comparison to what was observed in the past decades. This will lead to changes in flora and fauna. Because of the natural evolution of the climate system, living organisms, including humans, have learned to adapt to climate changes that cause changes inthe familiar environment. People have migrated because of climate changes. These problems and the possibility of reaching an agreement to limit human impact on earth's climate in order to avoid a temperature rise of more than 2°C, will be topics of discussion during the 21^st Paris Climate Change Conference, which will be held in the period November 30 to December 11th.

But what weather should we expect in Bulgaria during the upcoming winter season? Will skiers be able to enjoy lots of snow?

"This year is special because there are factors that affect the weather on a large scale. The so-called ‘El Niño’ process in the Pacific has a strong influence on the climate, which is expected to continue during the upcoming winter season. The phenomenon affects large areas of the Earth, and this year it is strong and affects seasons in Europe and Bulgaria, along with other factors such as the condition of North Atlantic Ocean. For this reason, it is very likely that this winter would be relatively mild, with average temperatures similar to last winter’s. Precipitation is expected to be near the average level, or less in comparison to last winter. In the mountains there won’t be lots of snow but that does not mean that there would be no conditions for winter sports," Ilian Gospodinov forecasts.