On the SmartBuoy, surface measurements of plant nutrient concentrations are
derived from two instruments. The NAS-3X in-situ nutrient analyser takes
hourly measurements of nitrate concentration, while lower frequency (daily)
measurements of nitrate and silicate concentration are derived from laboratory
analysis of water samples collected and preserved by the WMS-2 water sampler.
An estimate of phytoplankton concentration (biomass) is obtained twice per
hour using a fluorometer measuring chlorophyll fluorescence. To aid
interpretation of these data, SmartBuoy also takes measurements of
conductivity, temperature, suspended sediment concentration, light penetration
with the ESM2 logger. Data are telemetered every two hours using ORBCOMM
satellite telemetry.
The Celtic Deep SmartBuoy is located at 51.2495 N, 6.0818 W It started logging
in May 2009 and finished in February 2012.