Providing high quality chlorophyll–a data streams from moored observing systems over broad spatial and temporal scales – part II

Chlorophyll-fluorescence is known to vary on diel, regional and seasonal scales and is often used to reflect trends, rather than concentration in phytoplankton biomass. Australian coastal waters range from tropical to... [ view full abstract ]

Chlorophyll-fluorescence is known to vary on diel, regional and seasonal scales and is often used to reflect trends, rather than concentration in phytoplankton biomass. Australian coastal waters range from tropical to temperate waters, so a one fits all relationship between fluorescence and measured chlorophyll is not possible.
Since 2009, IMOS has deployed moored temperature, salinity, fluorescence and turbidity sensors at multiple sites within Australian coastal waters. Originally there were 9 sites, where in situ samples were collected regularly to aid in the calibration of the sensors. In 2013 two sites which were logistically difficult to sample were removed from the network, leaving 7 sites – Maria Island (Tas), Port Hacking (NSW), North Stradbroke Island (SE Qld), Yongala (N Qld), Rottnest Island (WA), Kangaroo Island (SA) and Darwin (NT).
At AMSA 2014, preliminary results based on data from just one site – North Stradbroke Island was presented. In 2015, the relationship between the data stream from the sensors with the coincident HPLC – Chl-a value determined from an in situ sample for the period 2009 – 2014 will be presented for each site. How these relationships can be used to adjust the fluorescence signal so that a more reliable chl-a concentration can be determined, at each site, on a greater temporal scale than is currently possible will be discussed together with an analysis of the different relationships determined between tropical and temperate waters.