Geography Topics

A halocline is a subtype of chemocline where salinity changes sharply with depth, acting as a structural barrier between layers of different water density.

The Ekman spiral describes how the Coriolis force and frictional drag between water layers cause net transport to move at an angle to the wind, cascading downward through the water column.

North Atlantic Deep Water (NADW) forms in the North Atlantic (Labrador and Greenland Seas) as brine rejection from ice formation and intense cooling increase water density, causing it to sink.

The Carbonate Compensation Depth (CCD) is the deep-ocean boundary below which high pressure and low temperature cause calcium carbonate to dissolve completely, leaving behind siliceous oozes or red clays.

Westward intensification is driven by the northward increase in the Coriolis parameter (the beta effect), compressing boundary currents on the western sides of basins into narrow, fast streams like the Gulf Stream.

Terrigenous (or lithogenous) sediments originate from land masses through weathering, river transport, and wind, settling mostly along continental shelves and slopes.

Rossby waves in the ocean propagate slowly westward, adjusting the internal thermal structure and thermocline depth across basin scales.

Active continental margins are associated with subduction zones or plate boundaries, featuring narrow shelves, steep slopes, and deep oceanic trenches.

For shallow-water waves (where depth is less than 1/20th of the wavelength), wave speed depends entirely on water depth ($C = \sqrt{gD}$), where $D$ is the depth.

The Benguela Current is the cold eastern boundary current of the South Atlantic Gyre, flowing northward along southwestern Africa.