final revision

part A: multiple choice answers

  1. C increasing temperature

  2. D pycnocline

  3. D tidal mixing

  4. D supply of nutrient rich deep water

  5. C reduced nutrient transport to the surface

  6. D dissolved organic matter (DOM)

part B: short answer questions

  1. a water mass is a body of seawater with a defined uniform temperature and salinity signature, which determines its density and allows it to be identified and traced as it moves through the water column

  2. thermocline is where there is a drastic change in temperature, halocline is where there is a drastic change in salinity, and pycnocline is where there is a drastic change in density. Denisty changes with increasing salinity, and decreasing temperature. So where there is a sharp change in temperature and salinity, there is similarly a sharp change in the density, creating a pycnocline

  3. upwelling happens when winds push the ocean water away form the coast or equator, creating a void that colder, nutrient rich water from teh deep comes to fill.

  4. residence time is the amount of time a chemical/inorganic compound remains in an ecosystem.

  5. POM/POC and algal blooms