Recent Change - Atmosphere

• Main Authors: Rutgersson, Anna, Jaagus, Jaak, Schenk, Frederik, Stendel, Martin, Lars, Barring, Briede, Agrita, Claremar, Bjorn, Hanssen-Bauer, Inger, Holopainen, Jari, Moberg, Anders, Nordli, Qyvind, Rimkus, Egidijus, Wibig, Joanna
• Format: Book Part
• Language: English
• Published: 2015
• Subjects: Baltic Sea; Climate change; Atmosphere; North Atlantic; North Atlantic oscillation
• Online Access: http://vu.lvb.lt/VU:ELABAPDB11698731&prefLang=en_US

This chapter describes observed changes in atmospheric conditions in the Baltic Sea drainage basin over the past 200–300 years. The Baltic Sea area is relatively unique with a dense observational network covering an extended time period. Data analysis covers an early period with sparse and relatively uncertain measurements, a period with well-developed synoptic stations, and a final period with 30+ years of satellite data and sounding systems. The atmospheric circulation in the European/Atlantic sector has an important role in the regional climate of the Baltic Sea basin, especially the North Atlantic Oscillation. Warming has been observed, particularly in spring, and has been stronger in the northern regions. There has been a northward shift in storm tracks, as well as increased cyclonic activity in recent decades and an increased persistence of weather types. There are no long-term trends in annual wind statistics since the nineteenth century, but much variation at the (multi-)decadal timescale. There are also no long-term trends in precipitation, but an indication of longer precipitation periods and possibly an increased risk of extreme precipitation events.