Chlorophyll concentrations were calculated from these time series (Figure 

 2-6), using shipboard calibration samples, collected with both sample 

 bottles and pumps at each fluorometer depth. At the event time scale 

 within these studies, chlorophyll biomass increased in response to wind- 

 driven upwelling off the Long Island coast. With a seasonal change in 

 stratification and prolonged nutrient addition by vertical mixing, diel 

 variations of chlorophyll (Owens et al., 1980), shifted from a pattern 

 dominated by tidal transport to one reflecting biological processes of 

 nutrient uptake and grazing. This early work suggests that both resolution 

 of the event scale ( 2 to 10 days) and the Nyquist sampling frequency 

 required to resolve phytoplankton cell division can, in fact, be achieved 

 with this approach. 



The initial fluorometer arrays have been redesigned as self-contained 

 units for taut-wire moorings to operate on the deeper shelf and in the 

 waters of the upper continental slope. The large battery pack has been 

 replaced with flash light batteries and the fluormeters now sample in a 

 burst-mode to conserve power. The time-averaged fluorescence data is 

 stored with an internal recording cassette logger for post retrieval 

 analysis rather than li ne-of-sight telemetry ashore as in the past. With 

 these new instruments, data collection could be continued for about 1 to 3 

 months unattended and may be extended for as much as one year with periodic 

 battery and cassette changes. 



Such an in situ fluorometry approach in either a moored or drifting mode, 

 provides the necessary time-series records for comparison of long-term 

 trends in the CZCS data set and for analysis of event responses within the 

 shorter periods taken during combined aircraft-ship studies of areal dis- 

 tribution and rate processes. By incorporating all of these recent 

 advances within a suitable MAREX sampling strategy (utilizing ships, 

 buoys, aircraft, and satellites), it is now possible to significantly 

 lower the variances in both estimates of phytoplankton abundance and popu- 

 lation growth rates in the coastal zone. With the appropriate data sets, 

 the future fluxes of carbon and/or nitrogen in the coastal and open ocean 



2-16 



