Variety Is The Spice Of ClimateClimate conditions can change for short periods of time. Those short time periods are called seasons. There are four defined seasons in a year even though there are some climates that do not show four seasonal changes each year. In a marine west coast climate there may be only subtle temperature changes between summer and fall. There are also larger climate changes that last years.
A Young Boy Causes TroubleA big topic on the West Coast of the United States is El Niño. El Niño is a weather phenomenon that happens every three to seven years. What makes it happen? On the Pacific Ocean there are constant winds called trade winds. They usually blow from east to west. Sometimes those winds slow down and the water current shifts directions. The currents no longer have the wind to push them so the warm water moves to the west coast of the American continents. This change in the direction of the current changes the weather and climates all over the world. In some places the temperature changes and in others there is more rain. It depends on what your climate was like before El Niño.
Who CHanged The Rain?Another large change in climates happened in the late nineteenth century. For some reason, in the tropical zone rainfall amounts increased all over the world for a few years. Since that time, the rainfall amounts have decreased every year. Scientists have not figured out if that was just something that happened at that time or if there is a larger cycle at work. Rain amounts may go up again in the future.
Warming UpGlobal warming is a variation that you may have discussed in school. As greenhouse gases increase in any atmosphere, IR radiation is trapped inside the lower layers of the atmosphere. This additional heat affects climates across the world and can create changes over hundreds of years. As the entire planet heats up, temperatures will increase in all climate zones. Extreme results can be long periods of drought and the melting of polar ice caps.
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Climate Connect: Questions from the Carolinas (USGS Video)
Useful Reference MaterialsEncyclopedia.com (Global Warming):
Wikipedia (El Niño):
Encyclopædia Britannica (Greenhouse Gas):