Download this lab as a Word document: Lab 6: Ocean Properties & Circulation (Please download required files below.)
The lab this week is fairly short. The goal is to give you a more visual overview of surface ocean properties and circulation and their relationship with climate change. The questions will require you to have mastered the material in the module, so make sure you read and understood them completely.
The goals of this lab are to:
- describe the distribution of temperature, salinity, and nutrients;
- investigate the processes that control surface water properties and
- consider changes in the coastal ocean in the future.
Files to download
Before you begin answering the Practice questions, please load and get comfortable turning on and off the following kmz files:
- Sea surface temperatures (World and Regional Sea Surface Temperature.kmz)
- Chlorophyll concentrations (chl.kmz)
- Surface ocean currents (2016 GCH Ocean currents.kmz)
Please Note: You will be downloading kmz files from the Internet this week, not directly from this Lab.
The map shows average Sea Surface Temperatures (SSTs). The colors are a little close together, so you will need to look carefully to determine trends. Note also the data are acquired from a bunch of different sources so there can be artificial “joins” on the map. We try to make sure these do not impact the questions. If certain areas don’t show the temperatures, keep rotating the globe.
- Where is the SST warmest? (for the lat long coordinates, hover your mouse and look at the coordinates bottom right)
A. Western equatorial Pacific (2N 140E)
B. Off the coast of Florida (30N 81W)
C. Off the coast of West Africa (25N 15W)
D. Off the coast of Western Australia (31S 114E)
- Of the following, where is the SST coolest?
A. St Lawrence Seaway (48N 63W)
B. English Channel (50N 3W)
C. Near the Falkland Islands 52S 63W
D. Labrador Sea 65N 60 W
- Which restricted basin has the coolest temperatures?
A. Black Sea
D. Hudsons Bay
Now, turn on the surface current kmz and answer the following questions. Note the white arrows are surface ocean currents and the blue and red lines are the global conveyor belt. If you don’t know where places are, you can search for them by adding a name in the box, top left.
- Look at the dominant current off the coast of Japan. Is it coming from the North or the South?
- Is the water off the coast of Japan warm or cold relative to areas at comparable latitude in the central Pacific?
- Based on your answers to the previous two questions, is the current off Japan warm or cold?
- Now, look at the area to the north of Antarctica on a global basis. What are the currents doing there?
A. Flowing around the continent from west to east
B. Flowing northward
C. Flowing southward
Now turn on the chlorophyll kmz and answer the following questions. The colors again are very subtle; make sure you use the scale at bottom right - anything lighter blue or white is considered high productivity.
- Which of the following locations had high productivity? (for the lat long coordinates hover your mouse and look at the coordinates bottom right)
A. Caribbean (19N 82W)
B. Offshore Brazil (12S 30W)
C. Offshore Peru (10S 79W)
D. Bahamas (24N 74W)
- Give a one-word answer for why productivity is high in that location.
- Find the South Equatorial Current in the Atlantic. Why is productivity high in that location?
A. Because evaporation leads to high chlorophyll contents
B. Because surface ocean currents draw surface waters away leading to upwelling
C. High temperatures lead to high chlorophyll contents
D. Because high precipitation leads to upwelling
- What is the coldest temperature in the surface ocean? (answer to the nearest whole degree)
The future: Observe the El Niño visualization for the years 2015-2016. Since warm water holds less oxygen than cold water, determine how the expansions of dead zones occur from 2015 to 2016.
- Was hypoxia more widespread in 2016 than in 2015? Yes or No.