The mid-eighties regime shift and appendicularian abundance

• Main Authors: Lopez-Urrutia, A, Beaugrand, G, Greve, W, Harris, RP
• Format: Text
• Language: unknown
• Published: 2007
• Subjects: Arctic; Helgoland; White Sea; Climate change; North Atlantic; Zooplankton
• Online Access: http://plymsea.ac.uk/id/eprint/5831/

There is accumulating evidence suggesting that a regime shift occurred in the North Atlantic during the mid-eighties. This shift has been reported primarily from Continuous Plankton Recorder (CPR) data as a stepwise change in plankton abundance and copepod community structure. Here we analyse the CPR data for appendicularian abundance to show that a similar stepwise increase occurred in the abundance of appendicularians during the mid-eighties. Furthermore, we compare these results to data recorded by other zooplankton time series programmes to show that a similar abrupt increase in appendicularian abundance during the mid-early eighties has also been recorded in other areas. The fact that such a change occurred at locations so distant apart as Helgoland Roads in the North Sea or the White Sea in the Arctic suggests that these changes have a global origin. The strong dependence of appendicularian phenology with temperature points out to direct links to global climate change.