All data on-board the Thetis Profiler is time stamped using the on-board processor clock. This clock provides 10 ms resolution. The on-board clock is synced to the shore side host controller computer during each surface telemetry session, though the user can...
Scientific
What vertical resolution in the environmental sensor data can the Thetis provide?
To first order, the vertical resolution is set by the vertical profiling speed. The profiling speed is user configurable (which can be changed during the deployment). At typical profiling speeds of 20 cm/sec, the Thetis Profiler provides the required 0.25 m vertical...
Deriving the vertical diffuse attenuation coefficient (Kd) from the absorption coefficient (a).
Derivation of Kd from a In what follows we have left off the dependence on wavelength. In addition we have left off effects due to inelastic scattering. Modeling Kd(z) requires the inclusion of the depth dependence of the shape of the radiance...
Does it matter whether you use natural or artificial seawater for calibrations? Which does Sea-Bird use?
For SBE 4 conductivity calibrations, Sea-Bird uses natural seawater that has been carefully collected, stored, UV irradiated, and filtered. Artificial seawater is not adequate if calibration errors are to be kept below 0.010 psu. Note: SBE 4 is the...
Is an instrument with the class based calibration still within the published specification for accuracy? If not, what is the accuracy?
Instrument specific calibrations are more accurate and correspond to the published accuracy specifications. The accuracy of the class based calibration is estimated to be 2.2 uM +/- 20%.
How does absorption from CDOM affect the SUNA V2 nitrate measurement?
The SUNA V2 determines nitrate concentrations from the shape of the UV absorption curve. The least squares curve fitting algorithm uses calibrated extinction coefficients for nitrate and bromide (strong absorbing species in salt water) to calculate the concentration...
Do I need accurate salinity and temperature data to correct the SeaFET™ pH output?
The acquisition of conductivity/salinity data alongside the SeaFETTM is recommended. The acquisition of temperature data is not necessary as the SeaFETTM performs temperature measurements. Typically, conductivity and temperature measurements are combined in...
What are the main differences between the multispectral and hyperspectral radiometers?
Sea-Bird Scientific multispectral 500 series radiometers measure light at each fixed wavelength with an interference filter/detector assembly. The analog output of each detector is amplified and digitized. The amplification stage and noise filtering is...
Can I use in air irradiance sensors in water and vice versa?
Sea-Bird Scientific has developed cosine collectors that are specifically designed to optimize performance in the intended media of operation (air or water). So in water irradiance sensors have cosine collectors that provide an excellent response in water but not in...
How does the FIRe System differ from Pulse Amplitude Modulated (PAM) fluorometer?
The FIRe System measures changes in chlorophyll fluorescence that occur during a short (100 - 400 ?s) but intense (> 20,000 ?mol photons m-2 s-1) flash of light whereas the PAM approach measures the fluorescence induced by a weak modulated light source while using...
Featured Posts
November 2023 Newsletter
Come See Us at AGU in San Francisco! Sea-Bird Scientific is excited to exhibit at the upcoming AGU Fall Meeting taking place in San Francisco, California, from December 11 – 15, 2023. Please come see members of our team at booth #604 to get answers to your...
Seattle Ocean Science Happy Hour
Please join us alongside BioSonics, Marine Technology Society, and Sequoia Scientific as we host a Seattle Ocean Science & Technology Conference Happy Hour! Date: Wednesday, November 29, 2023 from 5:30 - 8:30pm Location: National Nordic Museum | 2655 NW Market...
Featured in ECO Mag: Deep-Sea Exploration with the SBE 49 FastCAT
We were excited to be featured in ECO magazine’s latest digital edition of their Deep-Sea Exploration series. In the spring of 2018, Triton Submarines reached out to the team at Sea-Bird Scientific, to express interest in using our SBE 49 FastCAT CTD (conductivity,...