Sinking Particle Flux in the Western Antarctic Peninsula

 

The Palmer Long-Term Ecological Research (LTER) program studies an oceanic and coastal region along the Western Antarctic Peninsula - one of the most rapidly warming parts of our planet.  The program was originally started in the early 1990s in part to try to understand declining abundances of Adelie penguins in the region, although the LTER program studies the entire ecosystem.  Among other measurements, they have been measuring sinking particle flux using a moored sediment trap.  This moored sediment trap is basically an instrument that is attached to a line containing both midwater buoys and weights to anchor it to the bottom of the ocean.  The sediment trap hangs on this line at a depth of about 150 meters beneath the surface of the ocean.  The sediment trap includes a funnel to collect sinking particles and beneath that funnel is a series of rotating cups. The cups rotate approximately once every two weeks allowing the scientists to collect a time-series of sinking particles throughout the year.  Ever year, in January, they collect and then re-deploy the sediment trap, allowing them to get continuous bi-monthly measurements of particle (and carbon) flux from the surface into the deep ocean at this site about 130 km from shore.  However, because this site is far from shore and very difficult to get to, they cannot measure other properties at the site with the same frequency.  They do, however, have another station much closer to shore (<1 km from shore) at which they make many other measurements to which the sediment trap data can be compared.  This other data, which requires that scientists actually go out on a small boat to collect the samples, is only collected in the austral summer, however.  The scientists make all of this data freely available and if you want to download it for yourself you can access it at the Palmer LTER DataZoo website.

 

Please note that in this dataset the letters "NaN" means that a measurement was not taken.  Time-series evolve over time and logistical issues (e.g., 20-foot waves and 40-knot winds) can make it impossible to make every measurement every time.

 

Palmer LTER Offshore Sediment Trap Data.xlsx

 

Data Columns:

 Record = a unique sample number

 Deployment = a unique number corresponding to the annual sediment trap deployment

 Cup = which of the 21 cups of the sediment trap the sample came from

 Start Date = beginning time of collection

 End Date = end time of collection

 Duration = length of collection (unit = days)

 Mid-date = midpoint of collection

 Surface Phosphate =  Phosphate concentration at the surface ocean at station B (unit = millimoles of phosphate per meter cubed of seawater).  Phosphate is the most abundant phosphorus-containing nutrient available to phytoplankton.

 Surface Silicate =  Dissolved silicate (silicic acid) concentration at the surface ocean at station B (unit = millimoles of silicon per meter cubed of seawater).  Silicic acid is the most abundant phosphorus-containing nutrient available to phytoplankton.

 Surface Nitrate = Nitrate concentration at the surface ocean at station B (unit = millimoles of nitrogen per meter cubed of seawater).  NItrate is the most abundant nitrogen-containing nutrient available to phytoplankton.

 Surface Ammonium = Ammonium concentration at the surface ocean at station B (unit = millimoles of nitrogen per meter cubed of seawater).  Ammonium is the most easily-utilized nitrogen-containing nutrient available to phytoplankton and is rapidly recycled in the surface ocean.

 Surface 19'-butanoyloxyfucoxanthin = 19'-butanoyloxyfucoxanthin concentration at the surface at station B.  19'-butanoyloxyfucoxanthin is an "accessory" pigment that helps phytoplankton use wavelengths of light that are unavailable to Chlorophyll a.  19'-butanoyloxyfucoxanthin is most commonly found in diatoms.  Unit = micrograms 19'-butanoyloxyfucoxanthin per liter of seawater.

 Surface Fucoxanthin = Fucoxanthin concentration at the surface at station B.  Fucoxanthin is an "accessory" pigment that helps phytoplankton use wavelengths of light that are unavailable to Chlorophyll a.  Fucoxanthin is most commonly found in diatoms.  Unit = micrograms fucoxanthin per liter of seawater.

 Surface 19'-hexanoyloxyfucoxanthin = 19'-hexanoyloxyfucoxanthin concentration at the surface at station B.  19'-hexanoyloxyfucoxanthin is an "accessory" pigment that helps phytoplankton use wavelengths of light that are unavailable to Chlorophyll a.  19'-hexanoyloxyfucoxanthin is most commonly found in diatoms.  Unit = micrograms 19'-hexanoyloxyfucoxanthin per liter of seawater.

 Surface Chlorophyll a = Chlorophyll a concentration at the surface at station B.  Chlorophyll a is the most important photosynthetic pigment found in nearly all plants and phytoplankton (unit = micrograms of chlorophyll per liter of seawater).  This column was measured by high-pressure liquid chromatography

 Surface Particulate Organic Carbon = total amount of organic carbon contained in particles at the surface at station B (unit = milligrams of carbon per meter cubed).  It is equal to the sum of the organic carbon in phytoplankton + protistan zooplankton + heterotrophic bacteria + dead organic matter

 Surface Particulate Organic Nitrogen = total amount of nitrogen contained in particles at the surface at station B (unit = milligrams of nitrogen per meter cubed).  It is equal to the sum of the nitrogen in phytoplankton + protistan zooplankton + heterotrophic bacteria + dead organic matter

 Vertically-integrated Particulate Organic Carbon = total amount of organic carbon contained in particles in a vertical column of water at station B (unit = milligrams of carbon per meter squared).  It is equal to the sum of the organic carbon in phytoplankton + protistan zooplankton + heterotrophic bacteria + dead organic matter

 Surface Net Primary Productivity = net bicarbonate uptake by phytoplankton at the surface at Station B (units = milligrams of carbon per meter cubed of seawater per day)

 Vertically-integrated Net Primary Productivity = net bicarbonate uptake by phytoplankton at all depths in a vertical column of water  at Station B (units = milligrams of carbon per meter squared of seawater per day)

 Sinking Carbon Flux = organic carbon flux of sinking particles that were collected in the sediment trap (units = milligrams of organic carbon per meter squared per day)

 Sinking Nitrogen Flux = total nitrogen in sinking particles that were collected in the sediment trap (units = milligrams of nitrogen per meter squared per day)

 Sinking Phosphorus Flux = total phosphorus in sinking particles that were collected in the sediment trap (units = milligrams of phosphorus per meter squared per day)