Lake Geneva °C in 53 years), while the average temperature of surface water (5 meters deep) increased from 10.9 °C in 1970 to 12.9 °C in 2016 (+ 2 °C in 46 years). Lake Geneva (and particularly the lakeside parts of the city of Geneva) can be affected by the cold Bise, a north easterly wind. This can lead to severe icing in winter. The strength of the Bise wind can be determined by the difference in air pressure (in hectopascal [hPa]) between Geneva and Güttingen in canton of Thurgau. Bise arises as soon as the air pressure in Güttingen is higher
Lake Geneva than in Geneva. In 563, according to the writings of Gregory of Tours and Marius Aventicensis, a tsunami wave swept along the lake, destroying the fort of Tauredunum and other settlements, and causing numerous deaths in Geneva. Simulations indicate that the Tauredunum event was most likely caused by a massive landslide near the Rhône delta, which caused a wave eight meters high to reach Geneva within 70 minutes. In 888 the town was part of the new Kingdom of Burgundy, and, with it, was absorbed into the Holy Roman Empire in 1033. In the late 1960s, pollution made it dangerous