Lab 7.3 – Can you make predictions for patterns of variation for other years?

Estimated time to complete: 45 minutes
Materials needed: None

In the previous two activities, you looked at data from only one year. Using your knowledge of how seasonal cycles affect abiotic factors and primary production, can you predict the multi-year pattern of primary production (chlorophyll-a) and nitrate, based on the irradiance and SST data in the temperate Atlantic Ocean?

Explore the data below to see what you can observe about how irradiance and SST vary over four years (Graph 1 & 2). You can adjust the date range shown by using the slider bar to zoom in and out. However, before moving to the next step, make sure that you adjust the slider to show the full date range (all four years).

Then, on Graph 3, use your cursor to draw your prediction of how chlorophyll-a would vary over the same four years. On Graph 4, use your cursor to draw your prediction of how nitrate would vary over the same time frame.


Interpretation questions

  1. How well did your chlorophyll-a prediction match the actual chlorophyll-a readings? Discuss any similarities and differences you notice.
  2. Discuss some possible explanations for any discrepancies between the predicted and actual chlorophyll-a patterns.
  3. How did your prior knowledge of the relationships between primary production, irradiance, SST, and nitrate inform your predictions of the missing data?
  4. How confident are you in your prediction of nitrate concentrations despite the lack of data over the four years? Explain your reasoning behind your prediction.

Assessment question

  1. The area around the Coastal Pioneer Array recently has been identified as a high-use area for the North Atlantic Right Whales, especially during certain times of the year. Explain in detail why you think the whales are spending time in this region at certain times. Your explanation should include evidence from the first three activities of this lab (seasonal and annual cycles of primary production and abiotic variables).