Home >> Science & Nature >> Nature

How Does the Ocean Affect Weather?

The Earth constantly receives radiation from the sun. The oceans, which constitute approximately 70 percent of the planet's surface, slowly absorb and store warm solar energy, with the largest concentrations of radiant heat located close to the equator. Since high-latitude regions lose more radiation than they receive, much of the energy from equatorial waters flows toward the polar regions. Earth's oceans are the mechanisms by which some 30 percent of excess solar energy is transferred.

Temperature and Precipitation
- Although water has a high capacity for storing energy, it takes large amounts of solar radiation to raise ocean-water temperatures. This is a process that takes place gradually. Conversely, ocean temperatures cool more slowly than land temperatures. Large bodies of water, therefore, have a moderating effect upon air temperatures in coastal regions. Solar energy causes evaporation of ocean water, which eventually forms as clouds and precipitation when cooler ocean air collides with warmer temperatures characteristic of large land masses.
Ocean Currents
- Ocean currents resemble rivers flowing through much larger bodies of water. Depending upon their location, direction of flow and points of origin, the various ocean currents may have either a warming or cooling effect upon nearby land masses. The Gulf Stream, which originates in the Gulf of Mexico, is a warm ocean current that runs along the eastern seaboard of the United States, then traverses the North Atlantic before warming the British Isles and Western Europe.
El Niño and La Niña
- El Niño is a climate phenomenon that describes above-average surface-water temperatures in the eastern and central equatorial areas of the Pacific Ocean. The appearance of El Niño generally signifies a warmer winter for much of the United States, particularly across the northern tier of states. La Niña describes the condition under which surface-water temperatures in the Pacific equatorial regions are unusually cool. This phenomenon generally supports warmer-than-usual temperatures in the southeastern states while lowering temperatures in the Pacific Northwest.
Tropical Cyclones
- Hurricanes and other tropical cyclones form over areas where oceanic water temperatures average 80 degrees Fahrenheit or above. They require the existence of near-surface disturbances, such as thunderstorms, that have some rotation, low-level inflow and vertical wind shear between the troposphere and ocean surface. These devastating storms are accompanied by heavy rain and winds that may be well in excess of 100 miles per hour. According to the Atlantic Oceanographic Meteorological Laboratory, oceanic disturbances must be located at least 300 miles from the equator for a tropical cyclone to develop.
The Nor'easter
- A nor'easter is a cyclonic storm that develops and moves along the eastern seaboard of the United States and Canada. These weather events, which are primarily a winter phenomenon, form when southward-moving arctic air collides with warmer air created by the northward flowing Gulf Stream. The nor'easter, which is characterized by heavy rain or snow and gale-force winds, is capable of causing flooding and beach erosion.

Nature