Sebastian Luening, paleogeologist: In the Baltic Sea region, there have been demonstrable major climatic fluctuations over the last 1000 years. Warm and colder periods alternated, with major consequences for the lives of plants, animals and humans. During the "medieval warm period" between 950 and 1250 AD, the northern hemisphere, including the Baltic Sea region, had higher-than-average temperatures compared to the periods before and after. The summer of 2018 experienced warmer than normal temperatures in the Baltic region, making it difficult for those used to air conditioning in the United States to sleep without this convenience after a day of bicycling in Estonia, Latvia and Lithuania. Is this due to man's use of fossil fuels? This paleogeologist shows similar warm periods over the last 1000 years.