Trans-Atlantic Study of Calanus: Analysis of historical time series data

The objective of this subtask of the Trans-Atlantic
Study of Calanus (TASC) programme was to determine
trends and seasonal cycles in abundance of Calanus in
different regions of the NE Atlantic and examine
evidence for correlation between regions, by extending
the statistical time series analysis of data from the
Continuous Plankton Recorder (CPR) surveys carried out
for the North Sea during ICOS to include a wider area
of the North Atlantic and Norwegian Sea and draw this
together with an analysis of historical time series
data from Icelandic, Faroese, Norwegian and Russian
sources.

Supply of additional CPR data, beyond those obtained
in respect of ICOS, was negotiated with the Sir Alister
Hardy Foundation, UK. Long term data from sampling in
Icelandic waters was in manuscript form and was collated
and digitised at MRII. Similarly, access to data for
Faroese waters was be negotiated. Comprehensive data on
zooplankton in the Barents and Norwegian Seas are known
to exist at the PINRO in Murmansk. These were collated
and digitised through collaboration between UIT? and
local scientists in Russia (Degtereva 1979). The approach
to analysing the CPR and other data had two main thrusts.
The first of these is data analytic. This consists of
identifying and developing smoothing and filtering
procedures for the estimation of the long term trend
and the annual seasonal cycle for each series. The second
effort consists of the construction and validation of
suitable time series models for individual series.
The mixed nature of the data, referred to above,
necessitates the use of non linear time series modelling,
a major area of current research interest.