Recent Change—Atmosphere

Abstract

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.

Heat waves in Poland in the period 1951-2015: trends, patterns and driving factors

“…al. 2013;Rutgersson et al 2015), means that the probability of long and widespread heat wave occurrence is also increasing.…”

Variability of daily winter wind speed distribution over Northern Europe during the past millennium in regional and global climate simulations

“…The relationship between the NAO and mean temperature over Europe is a well-known effect (Rutgersson et al, 2015), in wintertime this is also positive in all models. This effect is caused by the advection of maritime air masses by stronger westerly winds in a more positive NAO state (also discussed in Gómez-Navarro et al, 2015a).…”

“…For example, Wang et al (2011) stated that NAO variations show a relationship with the 99th percentile of wind speed. The NAO itself could also be related to changes in European near-surface winter temperature (Rutgersson et al, 2015). In this regard, scenario simulations indicate a contradicting tendency of the NAO in a warmer future, depending on whether it is defined from the sea-level pressure (SLP) gradient or from the geopotential height at 500 mbar (Z500).…”

“…The coupled GCM ECHAM4-HOPE-G, also denoted in previous literature as ECHO-G (Legutke and Voss, 1999) consists of the atmospheric component (AGCM) ECHAM4 (Roeckner et al, 1996) and the ocean-ice component (OGCM) HOPE-G (Wolff et al, 1997). Both sub-models have been developed at the Max Planck Institute for Meteorology (MPI-M) in Hamburg.…”

“…The coupled GCM ECHAM5/MPI-OM consists of the atmospheric component ECHAM5 (successor of ECHAM4, Roeckner et al, 2003) and the ocean and sea-ice component MPI-OM (Marsland et al, 2003). The analysed simulation ECHAM5/MPI-OM (850-2005 AD) is part of an ensemble of simulations conducted by the Max Planck Institute for Meteorology in Hamburg and will hereafter simply be named ECHAM5.…”