El Nino is a global phenomenon, which affects both the seas and the whole atmosphere. Its effect on the world's weather is very significant. El Nino means the irregular warming of the ocean's surface. According to the scientists there were over ten big El Nino occurrences in the recent forty years. El Nino usually strikes in the South American coasts. Along the whole coast the water temperature is increasing. Not very strong occurrences make the water temperature to increase about 2 or 4 degrees Celsius. This doesn't have a huge impact on fishing. Sometimes stronger events appeared such as the one that occurred between 1982 and 1983, which disturbed the weather conditions around the whole world. Experts linked El Nino floods and droughts. Moreover, the number of hurricanes and tropical storms also increased. Unfortunately, El Nino can't be predicted, so we can't prepare ourselves for it.
El Nino caused a lot of biological changes. Because of the depressed pressure the photosynthetic activity is lowering and it results in a decrease in the number of the primary life forms, which constitutes the first elements of every food chain. Due to the warmer water, which is brought by warm waves, the less oxygen is consisted in the water which forces fish to swim deeper or in the other part of the ocean. There is the lack of information concerning the population of fish, when El Nino appears and we don't know if the number of them is decreasing. But many times scientists observe the decrease in the growth of these specious of fish.
The connection between some climatic and El Nino was confirmed many times. Experts needed many years of researches to fit the ocean waves and a lot of heavy rains. In the twenties the scientists tried to predict some Asian monsoons. When they managed to collect the weather records, they found out that there were some connections between barometer readings form the stations located on the eastern side of the Pacific and the western one. They discovered that when there was the pressure drop in the western part of the ocean, the pressure increased in its eastern part. This kind of phenomenon is called Southern Oscillation. When there is the high pressure on the eastern side of the ocean, there is low pressure on its western one. This hesitation of the pressure on the both sides of the Pacific makes the winds on the ocean's surface to blow. When the pressure is on the lowest level, the strong easterly ocean surface winds are weakening. But the huge changes take place on the western part of Pacific. When on the west the winds almost completely disappear, they weaken on the east side.
The winds, which arise on the ocean's surface, move the waves and are the main controller of the weather. These both winds: the easterly wind, which blows along the equator and the other one - the south easterly wind which blows along coasts of Peru and Ecuador are dragging the water surface. Due to the rotation of the Earth, the surface currents are deflected northward in the Northern Hemisphere and southward in the Southern Hemisphere. In this way the water is deflected from the equator in both these directions. As the water moves away, cold and nutrient-rich water comes from the lower parts to upper ones. This phenomenon is called the upwelling. The nutrient-rich water is also full of phytoplankton, which seems to be the first element of the food chain.
If the easterlies are blowing very strong, the other phenomenon appears. The upwelling of cold water caused the cooling of the air above, which makes the air too dense to get high to be condensed and then form the clouds. It results in that the strips of the ocean stay blow the clouds and it causes the heavy rain along the equatorial belt and on the western part of Pacific near Indonesia.
If the easterlies are weakening and retreating to the east during some earlier stages of El Nino, the upwelling slows down causing the ocean warming. Moreover, the moist over the ocean is getting warmer too. Then it becomes very light to create some deep clouds. These clouds produce a lot of heavy rain along the whole equator. These changes of the ocean temperatures cause the great rain zone in the western parts of Pacific and then move eastward. This causes some adjustments of the atmosphere and the pressure is dropping in the central part and eastern part of Pacific. Moreover, it is rising over Indonesia and Australia. It causes the further weakening and retreating of the easterlies. These small changes of the ocean and waves are amplifying and then the full blown El Nino appears.
Heavy tropical clouds change the flow of the air 5 or 10 miles over the sea level (for example rocks influence the flow of the stream). These kinds of clouds establish the waves in the flow of the air, which in turn affect the positions of monsoons. Also the belt of strong winds over the Earth is created. It separates the warm and cold areas of the Earth. The consequences of El Nino on the climate and the temperature are particularly visible during the wintertime. El Nino makes the winters milder in the western part of Canada and the United States, whereas they are very wet in the southern part of the United States. It means from Texas to Florida. Moreover, El Nino changes also the temperature during the other seasons. It was confirmed that during the winter El Nino is just the one of many factors which influences the temperature. El Nino doesn't always bring the tropical conditions.
Some experts discovered that the monsoon season is often connected with the droughts strike in Australia, Indonesia, India and other regions of Asia. However, the scientists didn't really know the magnitude of their. But in fact, they discovered only a small piece of information about this phenomenon. To explain the whole phenomenon the knowledge of winds patterns are required. They should be measured above the ground level, which weren't recorded yet. In the recent years the researchers managed to add some new pieces of information about Southern Oscillation.
March is quite predictable. El Nino appears in irregular intervals. Sometimes it appears two times in a decade. What is more, every single event is different then the other one. To confirm the statement an example is useful. El Nino stroke between 1982 and 1983 caught the scientists by surprise. It wasn't like the previous events of El Nino, because it wasn't preceded with the period of strong easterlies winds along the equator. What is more, it was set very late during the calendar year. Today to protect against the possibility of occurring of El Nino the experts record properly every single event, which may predict El Nino. The factors that may foresee El Nino are as follows: sea surface temperature, daily record of pressure and the average rainfall. The last one is regarded as the most important factor. Earlier it wasn't recognized as an important factor.
El Nino has a huge impact on economy. The fishing industry in Ecuador and Peru suffered very heavily, because their anchovy harvest was very weak. The sardines suddenly swam south into Chilean seas. Over 100 inches of rain dropped in Ecuador and in northern Peru. It caused that deserts nearby the coast turned into the area full of grass and lakes. This kind of phenomenon attracted a lot of swarms of grasshoppers. After the grasshoppers the explosions of toad and different specious of bird appeared. These newly created lakes were the temporary habitats for a lot of fish, which had moved with streams from the sea and then they had trapped. Most of these fish became the harvest for local people, when all of the lakes dried up. Moreover, in some flooded estuaries the shrimp production was very huge. On the other hand, there was the growth of mosquito-borne malaria cases in hospitals.
What is more, these abnormal winds changed the typical typhoons' patterns and they moved to Hawaii Islands and Tahiti, which aren't accustomed to the severe weather. These wind made the monsoon rains to fall in the central parts of the Pacific Ocean, instead of its western parts. This caused some droughts and forest fires in Indonesia and Australia. A lot of winter storms stroke the southern part of California, which caused floods in the southern States. The loss of the global economy is estimated at 8 billions of dollars. These were consequences of climate's changes.
To improve the researches some buoys were located in the ocean. They are supposed to help to understand and predict the ocean currents. Almost 70 buoys were moored by means of steel cable and linked the Galapagos Islands and New Guinea. They are located about 900 miles if we consider the east-west direction. In the north-south direction they are situated about 150 miles. The buoys measure wind, temperature, air humidity, temperature on the sea surface and temperature of subsurface down to 500 meters. A few buoys measure the ocean currents, the average rainfall and sun radiation. Every data is sent to the weather centres in every part of the world where all dates are analyzed and are helpful in climate forecasting. The data concerning wind and the ocean current transmitted from buoys are useful to find some missing ships in the western part of Pacific. To predict El Nino the photos and observations coming from the National and Oceanic Administration weather satellites are very helpful. Thanks to them the experts observe the tracking patterns of temperature on the sea's surface. The warm waters, which usually exist in the western part of the Pacific Ocean, are observed to move eastward in the direction to the western coasts of South America. Also the NASA satellite photos are very useful in observing the changes in the patterns of storms in the area of the equator, which cause the changes in the shifting situations of warm water. Some high cumulus clouds, which reach the atmosphere, make the regions of strong vertical motions bigger. They are measured to the eastward through the Pacific Ocean, because they are connected with the warm water on the ocean's surface. This kind of movement of the warm water changes the surface winds and also makes the winds blowing from the east to the west weaker. The experts know that El Nino's impact would be lower, if it was predictable.
For many years a lot of NASA missions have researched the other phenomena connected with El Nino. The first efforts to create the map of temperature of the sea's surface and clouds over the sea were carried out in 1978. Thanks to the satellite's photos the number of information increased. Since 1978 the researches have been also scientifically improved. The amount of channels also grew from four to five. These kinds of channels make possible to see many parts of the electromagnetic and infrared spectrum. It is predicted that in the future, one of the NASA missions called "Earth Probes", will be sent to carry out the science investigations, which will improve the knowledge about El Nino. Moreover, NASA has already initiated the mission called "Pathfinder Program", which is hoped to make the data from the last and current mission more visible. All these efforts will be directed to establishing the Earth Observing System (EOS). Thanks to EOS's satellites the scientists will be able to collect and observe the most important data. This information will increase our knowledge of the reasons and effects of this large-scale phenomenon such as El Nino.
Peru constitutes the excellent example of the fact that even short term forecasts of El Nino can be very useful. Economy of tropical developing countries, especially the food production, is strictly dependant to the sensitive climate changes.
Every year the changes in the sea's surface temperature through Peru's coasts have a great impact on the economy. When there is the warm water, it is very unfavourable for fish harvest and cause floods along the whole coast. The cold water is very pleased for fisherman. On the other hand, there is the crop failure, which isn't favourable for the agriculture. When there is the cold weather, it usually predicts strong El Nino period. Peruvians are used to concern about every single El Nino event.
As soon as the flood waters from the record-breaking flood from the years 1982 and 1983 started to recede, Peruvian farmers began to worry about the falling of the sea surface temperature. It would probably cause droughts and harvest failures. That time the government of Peru decided to introduce the program to foresee some climate swings. What is more, the farmers and governments agree to sow the special combination of crops to make the harvest bigger. The typical crops sowed in Peru are rice and cotton, which are very sensitive to climate changes and the whole harvest depends on the rainfall and its timing. If the rice is considered it needs very wet conditions, when it thrives and dry condition in the in ripening stage. Cotton, on the other hand, is resistant to the dry weather. So the foreseeing of El Nino tells the farmers whet they should sow: more rice or more cotton.
Today other countries take advantages of the Peru's success in predicting the weather for agricultural use. Brazil, Australia, India and Ethiopia try to duplicate Peru's success. These countries are situated on the tropics. Most of tropical countries need the exact El Nino predictions, but also some non-tropical countries, for example Japan and the United States, also require the proper prediction. The proper prediction will probably benefit in some strategic planning, agriculture, water resources and harvest of grain and extracting the fuel oil. A lot of scientists are carrying out the researches to predict El Nino. Governments of many countries support the designing and building the huge system to observe the tropical oceans. For every tropical country the prediction of El Nino and some other irregular phenomena in climate is very important. They should make the planning and framing easier.
The prediction of climate changes will improve the agriculture's management, fisheries, water reservoirs supply and some other resources. By introducing the system of predictions, some decisions will be easier.
