A global belt of strong westerly winds in the atmosphere. The jet stream forms the dividing line between warm, tropical air masses and cold, polar air masses. The jet stream steers weather systems around the Earth. The phase of the Southern Oscillation characterized by an abnormal weakening of the sea-level pressure contrast across the equatorial Pacific, accompanied by a weakening of the easterly trade winds. The rainy season over the tropical continents that normally occurs during the Summer, when the continents tend to be warmer than the nearby oceans.
Tiny plant species that float freely in the water.
Data obtained through historical records, such as core samples and tree rings. The periodic strengthening and weakening of the contrast in sea-level barometric pressure between the eastern and western sides of the Pacific. Normally, the pressure is higher on the eastern side, driving the easterly trade winds in the equatorial belt. Sea surface temperatures. Term used to describe the process by which cold, nutrient rich water rises up to the surface to replace water that has been moved away horizontally.