caa a22 4500 397551428 CHVBK 20180308164751.0 cr unu---uuuuu 161202e199612 xx s 000 0 eng 10.1006/jmsc.1996.0111 doi (NATIONALLICENCE)oxford-10.1006/jmsc.1996.0111 Sea surface temperature changes in the North Sea and their causes [Elektronische Daten] [Gerd A. Becker, Manfred Pauly] On the basis of 25 years of digitized weekly sea surface temperature (SST) maps of the North Sea, regional patterns, decadal changes, and trends are investigated with a view to re-examining the assumption of a general warming trend, as suggested by the observation that the years 1989-1994 represent the mildest winters observed in the past 50, perhaps even 130, years. A regional classification on the basis of an analysis of the patterns of SST anomaly fluctuations suggests eight different regions resembling those identified for the distribution of the North Sea water mass. The oceanic influence on the western side and the continental influence on the eastern side are reflected in the strikingly different behaviour of the western and eastern North Sea SST. Positive anomalies usually start in the Southern Bight and move, with a delay of several weeks, into the central and northern North Sea. None of the regions shows a temperature trend over the last 25 years. However, spectral analysis of long time series and the SST maps clearly indicate climatic fluctuations with a significant peak at a period of about 8 years, a periodicity also found in the North Atlantic Oscillation index (NAO). Salinity at the entrances to the North Sea is high when the NAO indicates an increased zonal atmospheric circulation, whereas the correlation between SST anomaly and NAO is quite low in these areas. By contrast, the correlation is high in the central North Sea. Changes in the air-sea exchange processes and advection of heat and salt from the North Atlantic appear to dominate climatic fluctuations in the North Sea. © 1996 International council for the Exploration of the Sea Articles nationallicence climatic fluctuations nationallicence North Atlantic Oscillation index nationallicence sea surface temperature nationallicence Becker Gerd A. Federal Maritime and Hydrographic Agency Postfach 311220, D-20305 Hamburg, Germany aut Pauly Manfred Universität Trier, Fachbereich IV - Geomathematik D-54286, Trier, Germany ICES Journal of Marine Science Oxford University Press 53/6(1996-12), 887-898 1054-3139 53:6<887 1996 53 icesjms https://doi.org/10.1006/jmsc.1996.0111 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1006/jmsc.1996.0111 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Becker Gerd A. Federal Maritime and Hydrographic Agency Postfach 311220, D-20305 Hamburg, Germany aut NATIONALLICENCE 700 1- Pauly Manfred Universität Trier, Fachbereich IV - Geomathematik D-54286, Trier, Germany NATIONALLICENCE 773 0- ICES Journal of Marine Science Oxford University Press 53/6(1996-12), 887-898 1054-3139 53:6<887 1996 53 icesjms Metadata rights reserved CC BY-NC-4.0 http://creativecommons.org/licenses/by-nc/4.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-oxford