Long description

Figure 11

A series of three line graphs to show the change in temperature, salinity and density with depth in the Atlantic Ocean.

All three graphs share the same vertical axis. The scale is the same for all three graphs and there are major and minor axis ticks on all graphs. However, the axis is only labelled and numbered in the graph on the left. Here the vertical axis is labelled 'depth/m' and goes down from 0 m to 200 m, with minor axis ticks at intervals of 10 m, but only the major axis ticks are numbered, from 0 m to 200 m in intervals of 50 m.

In all three graphs the horizontal axis is labelled and marked at the top of the graph and the major and minor axis tick marks are also shown, unlabelled, at the bottom of the graph.

All three graphs show the same colouration. The graph is pale blue at the top with a gradual transition to dark blue at the bottom.

In all three graphs there is a horizontal dashed line at a depth of 38. The area above this line is called the 'wind-mixed layer'.

The graph on the left shows the temperature data with a red line.

The horizontal axis is labelled 'temperature/°C'. It is marked from 16 °C to 30 °C in intervals of 2 °C with unlabelled minor ticks at intervals of 1 °C.

The red line starts at 28 °C at the surface and the temperature remains constant in the wind-mixed layer, with the red line running almost vertically to a depth of 38 m. Below this depth there is an initial sharp decrease in temperature to 26 °C at a depth of 45 m and then a gradual decrease to 19 °C at a depth of 200 m.

The graph in the middle shows the salinity data with a blue line.

The horizontal axis is labelled 'salinity'. It is marked from 34 to 38 in intervals of 1 with unlabelled minor ticks at intervals of 0.2. No units are indicated.

The blue line starts at 37.2 at the surface and salinity remains constant in the wind-mixed layer, with the blue line running almost vertically to a depth of 38 m. From there the salinity decreases gradually to approximately 36 at a depth of 200 m.

The graph on the right shows the density data with a green line.

The horizontal axis is labelled 'density/kg m⁻³' and is marked from 1024 kg m⁻³ to 1026 kg m⁻³ in intervals of 1 kg m⁻³.

The green line starts at 1024 kg m⁻³ at the surface and density remains constant in the wind-mixed layer, with the green line running almost vertically to a depth of 38 m. Below this depth there is an initial sharp increase in density to 1024.5 kg m⁻³ at 45 m, then a gradual increase in density to 1025.9 kg m⁻³ at a depth of 200 m.