BATS scientists use these contour plots to help visualize how data parameters change through time throughout the water column in the Sargasso Sea. Ocean temperature at BATS changes both with time and depth. As you can see, the difference in temperature in the surface waters ranges from 18 to 29 degrees Celsius. Nitrate and Phosphate are two essential nutrients for plant growth in the sea. At BATS, concentrations of these two nutrients are generally low.
Plants take up nutrients in the surface waters, so that they are almost undetectable.
However, in winter, storms mix deep, cold, nutrient-rich water into the surface waters. This can be seen well in the nitrate graph. Primary production is the rate of plant photosynthesis. At BATS, primary production tends to be highest in the springtime when there are nutrients present in the surface waters from winter mixing, and increased day length and strength of sunlight. This spring bloom is also reflected in the amount of Chlorophyll a pigments in the water.