75 oceanographic stations measured orthophosphate, nitrite, nitrate, ammonia, and silicic acid concentrations during the 1989 North Atlantic Pilot Project. The Netherlands contributed this dataset from the R.V. Tyro Leg 1 cruise, with analysis performed on Technicon Traacs 800 autoanalyzers. Approximately 1500 total samples were analyzed, with 400 reruns for phosphate.
Use Cases
- Model spatial gradients of orthophosphate and silicic acid across the 33N to 61.5N transect to understand nutrient availability for phytoplankton.
- Analyze correlations between nitrite, nitrate, and ammonia measurements to study nitrogen cycling processes in surface waters.
- Use the low-level nitrate and nitrite data from modified analyzer to examine distributions in oligotrophic regions below 1 micromol/kg.
- Investigate nutrient ratios (e.g., N:P, Si:N) from concurrent measurements to assess potential limiting factors for algal blooms.
- Validate or calibrate regional ocean biogeochemical models using in-situ ammonia and phosphate concentration data from a defined cruise track.
Strengths
- 75 sampling stations provide spatial coverage along a 20W meridian transect.
- Approximately 1500 total sample analyses for five nutrient species.
- Methodology details for each analyte, including specific colorimetric methods and wavelengths, are documented.
Limitations
- Data is from a single cruise leg in 1989, offering only a temporal snapshot.
- Sample size is limited to one region (North Atlantic near 20W), not globally representative.
- Approximately 400 phosphate samples required reruns, indicating potential measurement noise for that analyte.
Provenance
- Source
- Dutch JGOFS contribution to the North Atlantic Pilot Project (NAPP/NABE), hosted by NASA Earthdata.
- Collection Method
- Seawater samples drawn from Rosette samplers, analyzed unfiltered within 12 hours using Technicon Traacs 800 autoanalyzers with colorimetric methods.
- Time Range
- Cruise Leg 1: 31 July to 11 September 1989.
- Freshness
- null
- Geography
- North Atlantic Ocean at or near 20W longitude, between 33N and 61.5N latitude.