407 research outputs found
Climatic Impacts of Tropical Land Use Practices
Climatic Impacts of Tropical Land Use Practice
Telekonnektionsmuster-Sequenzen im Luftdruckfeld im Zusammenhang mit der NiederschlagsvariabilitÀt im Mittelmeerraum [Abstract]
Temperatur- und Niederschlagsanomalien an der Zugspitze in AbhÀngigkeit von nordatlantisch-europÀischen Telekonnektionsmustern
Untersuchung zur InhomogenitĂ€t von Extremtemperatur-Messreihen durch Ănderung der Messtechnik
Investigating regional source and sink patterns of Alpine CO2 and CH4 concentrations based on a back trajectory receptor model
Klimawandel und Extremereignisse im mediterranen GroĂraum: Kurzvorstellung eines DFG-Gemeinschaftsprojekts an den UniversitĂ€ten Augsburg und WĂŒrzburg [Abstract]
A new approach to classification of 40âyears of Antarctic sea ice concentration data
In this paper, we present a characterization of Antarctic sea ice based on the classification of annual sea ice concentration (SIC) data from 1979 to 2018. A clustering algorithm was applied to provide a climatological description of significant annual cycles of SIC and their spatial distribution around the Southern Ocean. Based on these classification results, we investigate the variability of SIC cycles on decadal and interâannual time scales. First, we discuss significant spatial shifts of SIC cycles during 1979â1998 and 1999â2018. In the Weddell Sea and in large parts of the Ross Sea, we observed higher SIC during the summer season, and an extension of sea ice cover in winter compared to the longâterm average. Second, we introduce the Climatological Sea Ice Anomaly Index (CSIAI), which is an annual measure for yearâround sea ice anomalies of the Southern Ocean and its regional subâsectors. By relating selected years of significant sea ice conditions (1981, 2007 and 2014) with atmospheric influences, we demonstrate that the CSIAI is very useful for assessing interâannular Antarctic SIC variability. Positive and negative sea ice anomalies can be qualitatively explained by atmospheric circulation anomalies in the years 1981 and 2007. However, in 2014, the year with the largest observed sea ice extent in our time series, we found that this positive sea ice anomaly was surprisingly not associated with a stationary and interâseasonally persistent pattern of circulation anomaly. This suggests that subâseasonal to seasonal circulation anomalies and oceanârelated processes favoured the formation of the sea ice maximum in 2014. With this study we provide additional information on the longâterm annual SIC variability around Antarctica. Furthermore, our classification approach and its results have potential for application in the evaluation of sea ice model results
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