IMPACTS OF CLIMATE CHANGE ON SEA TEMPERATURE
Robert Marsh and Elizabeth Kent
National Oceanography Centre, Southampton
Executive Summary
Sea surface temperatures (SST) have been rising in both the mid-latitude North Atlantic and UK coastal waters in recent decades. The broad Atlantic pattern of warming can be seen in Fig. 1, depicting SST anomalies in 2005/06, relative to the 1985 – 2003 average, based on satellite data. For this period, particularly strong anomalies (~2°C) are visible in the north-west Atlantic. In addition to surface warming, there is evidence from ‘Argo’ profiling floats of a simultaneous warming within the upper 1500m of the Atlantic, focussed within the 50-60N latitude. There is no clear consensus on the mechanism for this, which must either be due to surface heat gain or anomalous influx of warmer waters. Considering UK coastal waters only, using preliminary fields from the NOC SST in-situ dataset, widespread surface warming is evident around much of the coast throughout the 1970 – 2004 period (Fig. 2). The largest rates of warming are located within the English Channel and North Sea regions, where changes have approached 2°C in magnitude. The weakest warming is seen to the north-west of the UK. The pattern of these changes is broadly similar to that shown by marine air temperature, for the same period.
Level of Confidence
High
Key sources of Information
Please acknowledge this document as: Marsh, R. and Kent, E. (2006). Impacts of Climate Change on Sea Temperature in Marine Climate Change Impacts Annual Report Card 2006 (Eds. Buckley, P.J, Dye, S.R. and Baxter, J.M), Online Summary Reports, MCCIP, Lowestoft, www.mccip.org.uk