Lab 5.3 – Comparison of temperature, salinity, density, and stratification at polar and temperate locations.

Estimated time to complete: 60 minutes

Materials needed: none

Most of the variability in temperature, salinity and density occurs in ocean surface waters. Ocean locations differ slightly in these properties with latitude and season. In this activity you will compare the vertical density structuring at a temperate location (Coastal Pioneer) and a polar location (Global Argentine) and propose the most likely explanation for the differences.

Below you are able to see a dataset of temperature, salinity and density at the two locations over a year. You can interact with the data by:

  • Viewing a location by selecting either Coastal Pioneer or Global Argentine from the “Select a Site” pull-down menu under the 3-panel graph
  • Viewing a month by selecting the month of interest from the “And a Month” pull-down menu under the 3-panel graph
  • Viewing variable values by clicking on and moving along a profile. The values will appear at the bottom of the graphs.
  • Note the change in depth scale plotted for the two locations.


Quick Check Questions:


Interpretation Questions:

  1. Describe how temperature, salinity, and density change with depth at each location between seasons.
  2. Which ocean location is the saltiest? Freshest? Propose an explanation why one location is saltier than the other.
  3. Which of the locations shows the greatest stratification?
  4. During which season is the stratification the strongest at each location?
  5. Propose an explanation for the vertical density structure you observed at each ocean location.