If the forecast is a drought, on a hot day, heavy snow or storm, the sea has played an important role in this matter. Although the sun of the engine of all time on earth, ocean and atmosphere to produce the energy of the sun directly along certain routes both regional climate and individual weather events. For example, the climate of the West Coast of the United States, moderate winds from the Pacific Ocean warms. And Hurricane Mitch, which was about 10,000 people in Central America, killed in 1998 produced, as all hurricanes over the ocean.
The ocean plays a crucial role in determining the climate because of its ability to record, store and transport heat from the sun. Sea water has a world on the atmospheric temperature and circulation. In addition, sea water, the source of most precipitation.
The top 3 meters (10 feet) of water in the ocean more in the tropics and subtropics of more heat than the atmosphere should be over. The vast ocean heat capacity means that it requires a tremendous amount of heat energy to the temperature of a region of change of the sea, for example, it has several days to a cold area of the ocean a little fresher and make a lot of hot days to warm them.
The result is that the oceans have responded slowly to changes in the stations, forcing them to a moderating influence on climate. The sea makes the winters in the coastal regions and the summers warmer near the coast a bit cooler than they are inside.
Interactions Ocean-atmosphere
The sea can heat or cool the air in a number of different ways. For example, when the air is at a lower temperature than sea water, the ocean heat to the lower atmosphere that is less dense than the heat, the air molecules move several reasons for transfer. Thus, it creates a mass of air at low pressure on this part of the ocean. (Cool or cold waters lead the other hand, as the formation of air masses under high pressure air molecules closer together.) Because air always flows from high pressure areas to lower pressure winds in the area of low pressure is deflected.
In the winds that are affected by changes in pressure, the jet streams, fast-moving bands, the currents of air at high altitudes. The jets of energy supply in the development of storms at low altitudes, then the influence of their movement. So the ocean is to follow the direction of the storm. Storms, even changes in direction by the influence of changes in air pressure Ocean.
Ocean currents help for this purpose is widespread. Some currents carry warm water from the tropics and subtropics to the poles, while others, the cold water flows in the opposite direction to move. The Gulf Stream is a stream of warm water into the North Atlantic brings to the Florida of Europe. Before moving to Europe, the Gulf Stream is broken into several streams, one flowing into the British Isles and Norway. The heat from the warm wind blowing at present these areas are transported, helping the extremely cold winter.
Sun is like ocean circulation a bit uneven heating of the earth, the sun in the tropics receive more energy from the Sun's poles. If not for the moderating effects of ocean currents in the air temperature, would the tropics much warmer than they are and even colder polar regions.
In addition to the transfer of heat to the atmosphere and sea water in the air is absorbed by evaporation. If the sun's heat, the evaporation of surface water, hot water vapor rises into the atmosphere caused. As water vapor rises higher, the water droplets and ice crystals, which is cooled to form large clouds gather. Clouds on the return of moisture on the surface as rain, snow, sleet or hail. Most evaporation occurs in the warm waters of the tropics and subtropics, providing moisture to the tropical storms.
Virtually all the rain from the evaporation of sea water first this may surprise comes, it is logical, considering that about 97 percent of the total water on earth in the sea. Cycle of soil, water or hydrologic cycle is largely of endless movement of water from the ocean into the atmosphere and the sea.
The Role of Ocean Phenomena
The influence of the sea in the regular time by two phenomena that affect ocean climate models highlighted drama in the United States and many other countries. These phenomena El Niño and La Niña are called.
During an El Nino event, which usually takes about a year and to be repeated every two minutes to seven years, from east to west trade winds in the tropical Pacific weaken or change direction. The change in wind flow of the ocean to the east, transfer hot water from the western Pacific and eastern central Pacific. A mass of air at low pressure, type of air mass in a storm develops, builds on the warm waters of the central and eastern Pacific. This system takes air heavy rains of the Pacific coast of South America. At the same time, a high pressure in the western Pacific cold and can lead to drought in South Asia.
place due to changes in air pressure with El Niño interrupt the normal circulation of the atmosphere, the weather in the world will be changed. United States, such as El Niño usually results in milder winters in the Midwest, heavy rain in the south and dry in the Pacific Northwest. Forecasters said the El Niño of 1997-1998 led to severe flooding, landslides and several deaths in North Carolina, Tennessee and California.
La Niña often develops after an El Niño. La Niña is the opposite of El Nino and climate arises when trade winds push warm surface water westward, the lowest load of cold water in the East. Accordingly, an episode of La Niña through the water is cooler than normal water in the central and eastern Pacific and warmer than normal in the western Pacific is over. This can lead to severe storms in the region of South-East Asia and droughts in South America.
Forecasters said a little girl, took place in 1998-1999 also brought heavy rain and snow in the Midwest and Northwest.
Oceanographers said that the conditions typical for La Niña continued in 2001, well over a period of 1-2 years of La Niña. They said that this was probably due to the development of a state of long-term ocean, the Pacific decadal oscillation. Many scientists believe that this state, by cold waters off the Pacific coast of North and South America can, from 20 to 30 years and can be repeated every few decades. They said that can lead this phase of the cold water, cold winter in the Midwest and Northeast in the coming years.
Short-term and Long-term Influences
The reasons for the hot and cold water in the ocean to the development of seasonal weather conditions. Two dramatic examples of these events are cyclones and monsoon rains.
Hurricanes called typhoons when they occur in the Pacific Northwest and Cyclone , when they occur in the vicinity of Australia and the Indian Ocean, is known for its powerful and destructive winds. They are formed when seawater with a temperature above 26.5 degrees Celsius (80 degrees F) evaporates. Water vapor is absorbed by the surrounding air. increases as warm, moist air, the air pressure drops below. Cool air then stir in the area of low pressure will begin to turn around the track. As the air flow picks up speed, increasing the intensity of the winds.
Hurricanes are phenomena of the hot weather. In the Pacific and North Atlantic are most common in August and September, when water temperatures are higher. Typhoons in the Pacific Northwest to the year occur on but they are usually in the summer. Tropical storms often strike in the Indian Ocean in May and November. The mere threat of severe hurricanes in the U.S. on the east coast and along the Gulf of Mexico.
Hurricanes in the Atlantic may be more intense during La Niña.
How are hurricanes, monsoons some kind of seasonal weather phenomenon, for specific conditions ocean. In contrast to the destructive nature of hurricanes, however, the monsoon winds bring rain needed for crops irrigated rice tens of millions of people in Asia. The failure of the monsoon can lead to famine.
The monsoon winds hit continuously from April to October in the south-west in the northern Indian Ocean and the Earth. These winds caused by temperature differences between land and sea are caused during the summer, the sun heats the earth more than the sea and the air is heated above the ground and rises. To replace the air flowing moist air inland from the sea. As moist air rises over the land, it cools and condenses water vapor in clouds. The water in the clouds then falls as rain. In winter when the sea is warmer than the earth, the process is reversed. Then extends the cold, dry air sinks into the ground and from the North Sea.
The ocean affects not only the weather and climate in the short term, but also has a long-term impact on global climate. One way is by absorbing carbon dioxide from the atmosphere. Carbon dioxide is a kind of greenhouse gas emissions, a chemical that acts like a greenhouse trapping heat in the lower solar atmosphere. Many scientists believe that rising levels of carbon dioxide are released into the air by burning fossil fuels, increasing the surface temperature of the earth in a process of global warming known. Researchers predict that one consequence of global warming, the melting of glaciers and ice caps, with a resulting rise in sea level.
But the sea of help against global warming can use his ability to fight remove large amounts of carbon dioxide from the atmosphere. Is able to do this mainly due to the activity of tiny organisms called phytoplankton. These microbes carry out photosynthesis, using energy from sunlight to food from the chemical compound of carbon dioxide and water produce. Many researchers believe that if there is no absorption of carbon dioxide by marine organisms, global warming may occur at a rate much faster than it really is.
Much Remains Unknown
Whether harmful or beneficial to the population, the time depends on the ocean. The interaction between ocean and atmosphere are so complicated and complex than the prognosticators 2001 was a long way to go until they make reliable predictions in the long run. However, the interaction between water and air, is a basic fact of daily life. The next time you walk in the rain and watched the snow fall, a shelter against the cold, or sun bathing in the sun, not to forget the incredible power that the ocean climate.
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