Key Climate and Ocean Terms Defined
Cell Connect
A closed set of backward and side wind movements.
Ocean Currents
Movements are continuous, and water bodies are the main mechanism of heat transport, more effective than the atmosphere.
Surface Currents
The main ocean currents that run through the central zones of the oceans largely follow the pattern of anticyclonic winds, moving west and then east along the trade winds, carrying clouds and rainfall. Upon reaching the west (East Coast), they return to their origin; this is called the West Wind Drift. There are deviations towards higher latitudes, bringing warmth and moderating climate (e.g., the Gulf Stream), but there are also deviations towards the tropics.
Jet Streams
Located on the boundaries of convective cells, these currents are fast and very thin, ranging from west to east. They are found in the upper troposphere. The most powerful is the polar front jet stream.
Global Ocean
The interconnected set of all seas and oceans. It is central to global climate because it stores CO2 and transports heat and influences cloud cover.
Ocean Conveyor Belt
A great ocean current system that travels the Earth’s oceans. The first part flows as a deep undercurrent from Greenland, consisting of cold, salty waters. It crosses the Atlantic and reaches the Antarctic, where part returns as a surface flow towards the North Pole. From there, it returns in the opposite direction, guided by prevailing winds in the form of surface currents. It also regulates the amount of atmospheric CO2, as cold water holds a large amount of this gas, which is released in upwelling areas some 1,000 years later.
El Niño Phenomenon
The normal situation on the coast of Peru is that the trade winds push surface water westward, resulting in an upwelling of cold, nutrient-rich water and fertilization of the area. These winds originate from the anticyclone of Easter Island. The El Niño phenomenon, also known as the Southern Oscillation (ENSO), occurs every 3-7 years and lasts about 18 months, often being more intense around Christmas. It involves excessive heating of surface water in the Eastern Pacific (off the Peruvian coast). When the trade winds weaken, the westward push and upwelling decrease, leading to warmer surface waters. The effects of El Niño include declines in global fish production and rising ocean temperatures. It brings storms and torrential rains to Peru, California, and eastern East Africa, and severe drought to Brazil, South Africa, and the Philippines.
Causes of El Niño
- Global warming, which reduces the thermal contrast between the two shores of the Pacific, decreasing the intensity of trade winds and ocean currents.
- Increased volcanic activity on oceanic ridges, which raises the temperature of the ocean.
La Niña
Occurs when the normal situation is exaggerated; the trade winds blow with great force, coastal waters are colder than normal, leading to increased rainfall in the Eastern Pacific and droughts in South America.
Weather
The state of the atmosphere at a given place and time, referring to temperature, humidity, etc.
Climate
A set of meteorological phenomena that characterize the typical weather conditions at a particular place on Earth over a long period (typically 20-30 years).