SBC LTERData → Stearns Wharf

 About: 
Location: Latitude: 34° 24.48', Longitude: -119° 41.10'
Data Update Frequency: every 4 min.
 Descriptions of the Types of Data We are Collecting at Stearns Wharf: 

Temperature

  • Units: degrees Celcius or Fahrenheit
  • Instrument Range: -5 to 35 deg C (accuracy of +/- 0.005 deg C)
  • Description: Used here to denote the sea water temperature determined using the ITS-90 algorithm.

Tide

  • Units: feet above mean lower low tide [datum] (converted from db; a pressure change of 1 decibar equals about 1 meter of seawater)
  • Instrument Range: 0 to 20 m (accuracy of +/- 0.02 m)
  • Description: This is measured by a strain gauge sensor. The mounted pressure sensor records the distance between the sensor and the surface of the water in decibars. The sensor is mounted below of (nominally 2 m below mean lower low water), but near the surface of the ocean.
  • Notes: This is not an official tide guage, only an estimate of tidal action.

Salinity

  • Units: Practical Salinity Units
  • Instrument Range: 31.5 to 37 PSU
  • Description: We can not directly measure this quantity, so it is calculated from the conductivity measurement using the UNESCO (1981) algorithm. Salinity quantifies the total amount of dissolved solids in seawater, so a salinity of 33 means that each kilogram of seawater contains 33 grams of total dissolved solids, mostly sodium chloride.
  • Notes: It's possible that after some rain (which is not too common here), you can see the salinity spike downwards (because the sensor is near the surface, and the new fresh water is near the surface too since it's less dense).

Fluorometer

  • Units: ug/L
  • Instrument Range: 0 to 35 ug/L
  • Description: This value is converterd from voltage from the Fluorometer. It measures chlorophyll fluorescence by emitting an excitation beam at a known wavelength which causes chlorophyll to emit at a different, but known wavelength. This is a type of measurment of the amount of phytoplankton (unicellular plants in the water). If water appears more green than blue, their chlorophyll is probably the reason.