On Anomalous Sea Surface Temperatures in the

• Main Authors: Tore Furevik Geophysical, Tore Furevik
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2000
• Subjects: Barents Sea; Greenland; Norway; Denmark Strait; Greenland Sea; Iceland; Nordic Seas
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.16.9867; http://www.gfi.uib.no/~tore/OLpub/FullText/jclim2000ft.pdf

Gridded sea surface temperature (SST), sea level pressure, 10 m wind field, and ice concentration data from the winters 1982 to 1998 are used in a study of the large scale variability of the SSTs in the Nordic Seas. Mean fields are extracted, and areas of maximum variability identified. A complex principal component analysis is applied to identify coherent structure of variability in the SST field. The leading mode accounting for 39 percent of the variance, reveals a band of high correlations at increasing phase lags along the west coast of Norway, across the Greenland Sea, and south through the Denmark Strait. The SST data contains two cycles of low frequency variability during the 17 winters studied, having approximately 5 years and 12 years periods. For the eastern parts of the Nordic Seas, propagation speeds agree with other transport estimates. This indicates that SST anomalies are representing upper ocean heat anomalies advected by the mean flow from north of Scotland towards the Barents Sea. This is not true for the Greenland side of the Nordic Seas, where propagation speeds are unrealistically high. Composite maps of cold and warm years show that forcing from the wind field anomalies is likely to produce the observed SST anomalies here. No links are found between the SST anomalies in the Nordic Seas, and anomalies south of the Iceland-Scotland Gap. It is therefore believed that the upper ocean heat anomalies are mainly created inside the Nordic Seas region.