07.12.2007 14:23
Fires and floods, droughts and hurricanes all hit our Earth together in 1997. The fires turned the forests of Indonesia to ashes, then raged across the expanses of Australia. Downpours are frequent over the Chilean Atacama Desert, which is particularly dry. Heavy rains and floods did not spare South America either. The total damage from the willfulness of the elements amounted to about 50 billion dollars. The cause of all these disasters, meteorologists believe the phenomenon of El Niño.
El Niño means "baby" in Spanish. That's what they called the anomalous warming surface water Pacific Ocean off the coast of Ecuador and Peru, occurring every few years. This affectionate name only reflects the fact that El Niño most often begins around the Christmas holidays, and the fishermen of the west coast of South America associated it with the name of Jesus in infancy.
In normal years, along the entire Pacific coast of South America, due to the coastal rise of cold deep waters, caused by the surface cold Peruvian current, the temperature of the ocean surface fluctuates within narrow seasonal limits - from 15°С to 19°С. During the El Niño period, the ocean surface temperature in the coastal zone rises by 6-10°C. As evidenced by geological and paleoclimatic studies, the mentioned phenomenon exists for at least 100 thousand years. Fluctuations in the temperature of the surface layer of the ocean from extremely warm to neutral or cold occur with periods of 2 to 10 years. Currently, the term "El Niño" is used in relation to situations where abnormally warm surface waters occupy not only the coastal region near South America, but also most of the tropical Pacific Ocean up to the 180th meridian.
There is a permanent warm current, originating from the coast of Peru and stretching to the archipelago lying southeast of the Asian continent. It is an elongated tongue of heated water, equal in area to the territory of the United States. The heated water evaporates intensively and "pumps" the atmosphere with energy. Clouds form over the warm ocean. Usually trade winds (constantly blowing east winds in the tropical zone) drive a layer of this warm water from the American coast towards Asia. Approximately in the region of Indonesia, the current stops, and monsoon rains pour over southern Asia.
During El Niño near the equator, this current warms up more than usual, so the trade winds weaken or do not blow at all. The heated water spreads to the sides, goes back to the American coast. An anomalous convection zone appears. Rains and hurricanes hit Central and South America. Over the past 20 years, there have been five active El Niño cycles: 1982-83, 1986-87, 1991-1993, 1994-95 and 1997-98.
The La Niño phenomenon, the opposite of El Niño, manifests itself as a drop in surface water temperature below the climatic norm in the eastern tropical Pacific. Such cycles were observed in 1984-85, 1988-89 and 1995-96. Unusually cold weather established in the eastern Pacific during this period. During the formation of La Niño, the trade winds (east) winds from the west coast of both Americas increase significantly. The winds shift the zone of warm water and the "language" of cold waters stretches for 5000 km, exactly in the place (Ecuador - Samoa Islands), where during El Niño there should be a belt of warm waters. During this period, powerful monsoon rains are observed in Indochina, India and Australia. The Caribbean and the United States suffer from droughts and tornadoes. La Niño, like El Niño, most often occurs from December to March. The difference is that El Niño occurs on average once every three to four years, while La Niño occurs once every six to seven years. Both phenomena bring with them an increased number of hurricanes, but during La Niño there are three to four times more than during El Niño.
According to recent observations, the reliability of the onset of El Niño or La Niño can be determined if:
1. At the equator, in the eastern Pacific Ocean, a patch of warmer water than usual (El Niño), colder (La Niño) is formed.
2. The atmospheric pressure trend between the port of Darwin (Australia) and the island of Tahiti is compared. With El Niño, pressure will be high in Tahiti and low in Darwin. With La Niño, the opposite is true.
Research over the past 50 years has established that El Niño means more than just the coordinated fluctuations in surface pressure and ocean water temperature. El Niño and La Niño are the most pronounced manifestations of interannual climate variability on a global scale. These phenomena are large-scale changes in ocean temperatures, precipitation, atmospheric circulation, vertical air movements over tropical part Pacific Ocean.
anomalous weather on the globe during El Niño
In the tropics, there is an increase in precipitation over areas east of the central Pacific and a decrease from the norm over northern Australia, Indonesia and the Philippines. In December-February, more than normal precipitation is observed along the coast of Ecuador, in northwestern Peru, over southern Brazil, central Argentina and over the equatorial, eastern part Africa, during June-August in the western United States and over central part Chile.
El Niño events are also responsible for large-scale air temperature anomalies around the world. During these years, there are outstanding temperature rises. Warmer than normal conditions in December-February were over southeast Asia, over Primorye, Japan, the Sea of Japan, over southeast Africa and Brazil, southeast Australia. Warmer than normal temperatures occur in June-August along the west coast of South America and over southeastern Brazil. Colder winters (December-February) occur along the southwest coast of the United States.
Abnormal weather conditions on the globe during the La Niño years
During La Niño periods, precipitation increases over the western equatorial Pacific, Indonesia and the Philippines and is almost completely absent in the eastern part. More precipitation falls in December-February in the north of South America and over South Africa, and in June-August over southeastern Australia. Dryer-than-normal conditions occur over the coast of Ecuador, over northwest Peru and equatorial east Africa during December-February, and over southern Brazil and central Argentina in June-August. There are large-scale deviations from the norm around the world with the most large quantity areas experiencing abnormally cool conditions. Cold winters in Japan and the Primorye, over South Alaska and western, central Canada. Cool summer seasons over southeast Africa, over India and southeast Asia. More warm winters over the southwestern United States.
Some aspects of telecommunication
Despite the fact that the main events associated with El Niño occur in the tropical zone, they are closely related to processes occurring in other regions of the globe. This can be traced on long-distance communications over the territory and in time - teleconnections. During El Niño years, energy transfer to the troposphere of tropical and temperate latitudes increases. This is manifested in an increase in thermal contrasts between tropical and polar latitudes, and intensification of cyclonic and anticyclonic activity in temperate latitudes. The frequency of occurrence of cyclones and anticyclones in the northern part of the Pacific Ocean from 120°E was calculated at the Far Eastern Research Institute of Geological Research. up to 120°W It turned out that the cyclones in the band 40°-60° N.L. and anticyclones in the band 25°-40° N.L. formed in subsequent winters after El Niño more than in previous ones; processes in winter months after El Niño are characterized by greater activity than before this period.
During the El Niño years:
1. weakened Honolulu and Asian anticyclones;
2. the summer depression over southern Eurasia is filled, which is the main reason for the weakening of the monsoon over India;
3. the summer depression over the Amur basin, as well as the winter Aleutian and Icelandic depressions, are more developed than usual.
On the territory of Russia during the El Niño years, areas of significant air temperature anomalies are distinguished. In spring, the temperature field is characterized by negative anomalies, that is, spring during El Niño years is usually cold in most of Russia. In summer, the center of negative anomalies over Far East and Eastern Siberia, and pockets of positive air temperature anomalies appear over Western Siberia and the European part of Russia. V autumn months no significant air temperature anomalies over the territory of Russia have been identified. It should only be noted that in the European part of the country the temperature background is slightly lower than usual. El Niño years experience warm winters over for the most part territory. The center of negative anomalies can be traced only over the northeast of Eurasia.
We are currently in a weakening El Niño cycle - a period of average distribution of ocean surface temperatures. (The El Niño and La Niño events represent opposite extremes of ocean pressure and temperature cycles.)
Over the past few years, achieved great success in a comprehensive study of the El Niño phenomenon. Scientists believe that the key issues of this problem are fluctuations in the system atmosphere - ocean - Earth. In this case, atmospheric oscillations are the so-called Southern Oscillation (coordinated surface pressure oscillations in a subtropical anticyclone in the southeast Pacific Ocean and in a trough stretching from northern Australia to Indonesia), ocean oscillations - El Niño and La Niño phenomena and Earth oscillations - motion geographic poles. Also great importance in the study of the phenomenon of El Niño is the study of the impact of external cosmic factors on the Earth's atmosphere.
Especially for Primpogoda, the leading weather forecasters of the Department of Meteorological Forecasts of the Primorsky UGMS T. D. Mikhailenko and E. Yu. Leonova
Must retreat. It is being replaced by a diametrically opposite phenomenon - La Niña. And if the first phenomenon with Spanish can be translated as "child" or "boy", then La Niña means "girl". Scientists hope that the phenomenon will help to somewhat balance the climate in both hemispheres, lowering average annual temperature, which is now rapidly flying up.
What is El Niño and La Niña
El Niño and La Niña are warm and cold currents or equatorial zone The Pacific Ocean has opposite extremes in water temperature and barometric pressure that last about six months.
Phenomenon El Niño consists in a sharp increase in temperature (by 5-9 degrees) of the surface layer of water in the eastern Pacific Ocean over an area of about 10 million square meters. km.
La Niña- the opposite of El Niño - manifests itself as a decrease in surface water temperature below the climatic norm in the east of the tropical Pacific Ocean.
Together they represent the so-called Southern Oscillation.
How is El Niño formed? Near the Pacific coast of South America, the cold Peruvian current operates, which arises due to the trade winds. Approximately once every 5-10 years, the trade winds weaken for 1-6 months. As a result, the cold current stops its “work”, and warm waters move to the shores of South America. This phenomenon is called El Niño. The energy of El Niño is able to disturb the entire atmosphere of the Earth, provokes ecological disasters, the phenomenon is involved in numerous weather anomalies in the tropics, which often lead to material losses and even human casualties.
What will La Niña bring to the planet?
Just like El Niño, La Niña appears with a certain cyclicity from 2 to 7 years and lasts from 9 months to a year. The phenomenon threatens the inhabitants of the Northern Hemisphere with a decrease in winter temperature by 1-2 degrees, which in the current conditions is not so bad. If we consider that the Earths have moved, and now spring comes 10 years earlier than 40 years ago.
It should also be noted that El Niño and La Niña do not have to follow each other - often there can be several "neutral" years between them.
But don't expect La Niña to come quickly. Judging by the observations, this year will be dominated by El Niño, as evidenced by monthly both planetary and local scales. "Girl" will begin to bear fruit no earlier than 2017.
Can you imagine such a picture in the underground passage of your city?
But in vain. Everything is possible in our life, and even more!
Temperatures are rising, the climate is changing, rivers are overflowing, the world's oceans are rising, and scammers are skimming the cream off people's fears. global warming
and global example to that - the premiere of the film "". What, you think?
And here she is!
Recent sea level data from NASA (with the Jason-2 oceanography satellite) show that a large-scale, persistent weakening of the winds in the western and central equatorial Pacific during October caused a strong eastward moving wave of warm water. In the central and eastern equatorial Pacific Ocean, this warm wave manifests itself as an area of more high level sea, compared to normal and warmer sea surface temperatures.
The image was created using data collected by a US/European satellite during a 10-day period spanning late October and early November. The picture shows a red and white area in the central and eastern equatorial Pacific Ocean, which is about 10 to 18 centimeters above normal. These areas contrast with the western equatorial Pacific, where more low level water (blue and purple areas) between 8 to 15 centimeters below normal. Along the equator, red and white represent areas where sea temperatures surfaces one to two degrees Celsius above normal.
It is a set of interacting parts of one global system ocean-atmospheric climate fluctuations that occur as a sequence of oceanic and atmospheric circulations. This is the world's best-known source of interannual weather and climate variability (from 3 to 8 years).
The signs of El Niño are as follows:
Rising air pressure over the Indian Ocean, Indonesia and Australia.
Warm air appears next to Peru, causing rain in the deserts.
Warm water spreads from the western Pacific to the eastern. She brings rain with her, causing it in areas where it is usually dry.
As El Niño's warm waters feed storms, it creates increased rainfall in the east-central and eastern Pacific Oceans.
The west of the Antarctic Peninsula, Ross Land, the Bellingshausen and Amundsen seas are covered with large amounts of snow and ice during El Niño. The latter two and the Wedell Sea are getting warmer and under higher atmospheric pressure.
In North America, winters tend to be warmer than usual in the Midwest and Canada, while it is getting wetter in central and southern California, northwestern Mexico, and the southeastern United States. The Pacific Northwest states, in other words, are drained during El Niño.
Based on these data, I can write new scenario for a crushing blockbuster. As usual: apocalypse, catastrophe, panic… El Niño 2029 or El Niño 2033. Now it is fashionable to invent everything with numbers. Or maybe just.
El Ninh oh-oh
Phenomenon La Nina (La Nina, "girl" in Spanish) is characterized by an anomalous decrease in water surface temperature in the central and eastern parts of the tropical Pacific Ocean. This process is the reverse of El Nino (El Nino, "boy"), which is associated, on the contrary, with warming in the same zone. These states replace each other with a frequency of about a year.
Both El Niño and La Niña affect the circulation patterns of ocean and atmospheric currents, which in turn affect the weather and climate around the globe, causing droughts in some regions, hurricanes and heavy rains- in others.
After a period of neutrality in the El Niño-La Niña cycle observed in mid-2011, the tropical Pacific began to cool in August and a mild to moderate La Niña has been observed from October to date.
“Forecasts made on the basis of mathematical models and their expert interpretation indicate that La Niña is close to maximum strength and is likely to slowly weaken in the coming months. However, current methods do not allow forecasting the situation beyond May, so it is not clear what situation will develop in the Pacific - whether it will be El Niño, La Niña or neutrality," the statement said.
Scientists note that the La Niña of 2011-2012 was much weaker than in 2010-2011. Models predict that temperatures in the Pacific will approach neutral levels between March and May 2012.
La Niña in 2010 was accompanied by a decrease in the area of clouds and an increase in the trade winds. Reduced pressure led to heavy rain in Australia, Indonesia and countries South-East Asia. In addition, according to meteorologists, it is La Niña that is responsible for heavy rains in the south and drought in the east. equatorial Africa, as well as for the dry situation in the central regions of southwestern Asia and in South America.
El Niño(Spanish) El Nino— baby, boy) or southern oscillation(English) El Niño/La Niña - Southern Oscillation, ENSO ) is a fluctuation in the temperature of the surface water layer in the equatorial part of the Pacific Ocean, which has a noticeable effect on the climate. In a narrower sense El Niño — phase of the southern oscillation, in which the area of heated near-surface waters is shifting to the east. At the same time, the trade winds weaken or stop altogether, upwelling slows down in the eastern part of the Pacific Ocean, off the coast of Peru. The opposite phase of the oscillation is called La Niña(Spanish) La Nina— baby girl). The characteristic time of oscillation is from 3 to 8 years, however, the strength and duration of El Niño in reality varies greatly. So, in 1790-1793, 1828, 1876-1878, 1891, 1925-1926, 1982-1983 and 1997-1998 powerful El Niño phases were recorded, while, for example, in 1991-1992, 1993, 1994 this phenomenon , often repeating, was weakly expressed. El Niño 1997-1998 was so strong that it attracted the attention of the world community and the press. At the same time, theories about the connection of the Southern Oscillation with global climate changes spread. Since the early 1980s, El Niño also occurred in 1986-1987 and 2002-2003.
Normal conditions along the western coast of Peru are determined by the cold Peruvian Current, carrying water from South. Where the current turns west, along the equator, cold and plankton-rich water rises from deep depressions, which contributes to the active development of life in the ocean. The cold current itself determines the aridity of the climate in this part of Peru, forming deserts. The trade winds drive away the heated surface layer of water into western zone tropical Pacific Ocean, where the so-called tropical warm basin (TTB) is formed. In it, the water is heated to depths of 100-200 m. Atmospheric Walker circulation, which manifests itself in the form of trade winds, coupled with low pressure over the Indonesia region, leads to the fact that in this place the level of the Pacific Ocean is 60 cm higher than in its eastern part . And the water temperature here reaches 29 - 30 ° C against 22 - 24 ° C off the coast of Peru. However, everything changes with the onset of El Niño. The trade winds are weakening, the TTB is spreading, and a huge area of the Pacific Ocean is experiencing a rise in water temperature. In the region of Peru, the cold current is replaced by a warm water mass moving from the west to the coast of Peru, upwelling weakens, fish die without food, and westerly winds bring moist air masses to the desert, showers that even cause floods. The onset of El Niño reduces the activity of Atlantic tropical cyclones.
The first mention of the term "El Niño" dates back to 1892, when Captain Camilo Carrilo told a congress Geographical Society in Lima that the Peruvian sailors called the warm north current "El Niño", as it is most noticeable during the days of the Catholic Christmas. In 1893, Charles Todd suggested that droughts in India and Australia occur at the same time. The same was pointed out in 1904 by Norman Lockyer. The connection of the warm northern current off the coast of Peru with floods in that country was reported in 1895 by Pezet and Eguiguren. The Southern Oscillation was first described in 1923 by Gilbert Thomas Walker. He introduced the terms Southern Oscillation, El Niño and La Niña, and considered the zonal convection circulation in the atmosphere in the equatorial zone of the Pacific Ocean, which now received his name. For a long time, almost no attention was paid to the phenomenon, considering it to be regional. Only towards the end of the 20th century. links El Niño with the planet's climate.
El Niño 1997 (TOPEX)
Quantitative description
At present, for a quantitative description of the phenomenon, El Niño and La Niña are defined as temperature anomalies of the surface layer of the equatorial part of the Pacific Ocean with a duration of at least 5 months, expressed in a deviation of water temperature by 0.5 ° C to a greater (El Niño) or less (La Niña) side.
The first signs of El Niño:
- Increasing air pressure over Indian Ocean, Indonesia and Australia.
- The drop in pressure over Tahiti, over the central and eastern parts of the Pacific Ocean.
- The weakening of the trade winds in the South Pacific until they stop and the wind direction changes to the west.
- Warm air mass in Peru, rains in the Peruvian deserts.
In itself, a 0.5 °C increase in water temperature off the coast of Peru is considered only a condition for the occurrence of El Niño. Usually such an anomaly can exist for several weeks, and then safely disappear. Only a five-month anomaly classified as an El Niño event, can cause significant damage to the economy of the region due to a drop in fish catches.
Also used to describe El Niño southern oscillation index(English) Southern Oscillation Index, SOI ). It is calculated as the difference in pressure over Tahiti and over Darwin (Australia). Negative values index show about the El Niño phase, and the positive ones La Niña .
The influence of El Niño on the climate of various regions
In South America, the El Niño effect is most pronounced. This phenomenon usually causes warm and very humid summer periods(December to February) on the northern coast of Peru and in Ecuador. If El Niño is strong, it causes severe flooding. Such, for example, occurred in January 2011. Southern Brazil and northern Argentina also experience wetter than usual periods, but mainly in the spring and early summer. Central Chile experiences a mild winter with plenty of rain, while Peru and Bolivia experience occasional winter snowfalls that are unusual for the region. more dry and warm weather observed in the Amazon, in Colombia and Central America. Humidity is decreasing in Indonesia, increasing the likelihood of forest fires. This also applies to the Philippines and northern Australia. From June to August, dry weather occurs in Queensland, Victoria, New South Wales and eastern Tasmania. In Antarctica, the west of the Antarctic Peninsula, Ross Land, the Bellingshausen and Amundsen Seas are covered with large amounts of snow and ice. At the same time, the pressure increases and they become warmer. In North America, winters tend to get warmer in the Midwest and Canada. Wetter in central and southern California, northwestern Mexico and the southeastern United States, and drier in the Pacific Northwest. During La Niña, by contrast, the Midwest becomes drier. El Niño also leads to a decrease in the activity of Atlantic hurricanes. Eastern Africa, including Kenya, Tanzania and the White Nile Basin, experience long rainy seasons from March to May. Droughts haunt the southern and central regions of Africa from December to February, mainly Zambia, Zimbabwe, Mozambique and Botswana.
An El Niño-like effect is sometimes observed in the Atlantic Ocean, where the water along the equatorial coast of Africa becomes warmer, while off the coast of Brazil it becomes colder. Moreover, there is a connection between this circulation and El Niño.
The impact of El Niño on health and society
El Niño causes extreme weather patterns associated with epidemic disease frequency cycles. El Niño is associated with an increased risk of developing mosquito-borne diseases: malaria, dengue fever, and Rift Valley fever. Malaria cycles are associated with El Niño in India, Venezuela and Colombia. An association has been observed with outbreaks of Australian encephalitis (Murray Valley Encephalitis - MVE), which manifests itself in the south-east of Australia after heavy rains and floods caused by La Niña. A prime example is a severe outbreak of Rift Valley fever due to El Niño following extreme rainfall in northeastern Kenya and southern Somalia in 1997-98.
It is also believed that El Niño may be associated with the cyclical nature of wars and the emergence of civil conflicts in countries whose climate depends on El Niño. A study of data from 1950 to 2004 showed that El Niño is associated with 21% of all civil conflicts of this period. At the same time, the risk of civil war twice as high in El Niño years as in La Niña years. It is likely that the link between climate and military operations is mediated by crop failures, which often occur during hot years.
The La Niña phenomenon is an anomalous cooling of the water surface in the central and eastern parts of the tropical Pacific Ocean in winter. According to Japanese meteorologists, the most low temperatures were recorded in mid-February, but by the beginning of March, the indicators reached a normal level. According to forecasters, this is a sign of the imminent final onset of spring - at least in Japan, located in the Pacific Ocean. Currently, experts are studying the possibility of the opposite phenomenon occurring in the coming summer - El Niño - which is characterized by an abnormal increase in water temperature in the Pacific Ocean.
Typically, La Niña results in heavy rainfall and tropical storms along the western coast of South America, Southeast Asia, and eastern equatorial Africa. Nevertheless, this phenomenon can also affect the weather on a global scale. In particular, this winter, the phenomenon has become one of the factors that led to severe cold in Europe, ITAR-TASS reports.
http://news.rambler.ru/13104180/33618609/
The La Niña climate phenomenon, associated with a decrease in water temperatures in the equatorial Pacific Ocean and affecting weather conditions almost throughout the globe, has disappeared and most likely will not return until the end of 2012, the World Meteorological Organization (WMO) said in a statement.
The La Nina phenomenon (La Nina, "girl" in Spanish) is characterized by an anomalous drop in water surface temperature in the central and eastern tropical Pacific. This process is the opposite of El Nino (El Nino, "boy"), which is associated, on the contrary, with warming in the same zone. These states replace each other with a frequency of about a year.
After a period of neutrality in the El Niño-La Niña cycle observed in mid-2011, the tropical Pacific began to cool in August, and a weak to moderate La Niña event has been observed from October to date. By early April, La Niña had completely disappeared, and so far, neutral conditions have been observed in the equatorial Pacific Ocean, experts write.
"(Analysis of simulation results) suggests that La Niña is not likely to return this year, while the probabilities of remaining neutral and El Niño in the second half of the year are about equal," the WMO said in a statement.
Both El Niño and La Niña affect the circulation patterns of ocean and atmospheric currents, which in turn affect weather and climate around the globe, causing droughts in some regions, hurricanes and heavy rains in others.
Message from 05/17/2012
The climate phenomenon La Niña, which took place in 2011, was so strong that it eventually led to a drop in global sea levels by as much as 5 mm. With the advent of La Niña, there was a shift in Pacific surface temperatures and precipitation patterns around the world as ground moisture began to leave the ocean and head to land in the form of rain in Australia, in the north of South America, in Southeast Asia.
The alternating dominance of a warm oceanic phase in the southern oscillation phenomenon, El Niño, or a cold phase, La Niña, can change world sea levels so dramatically, but satellite data inexorably indicate that somewhere since the 1990s, global levels water still rise to a height of about 3 mm.
As soon as El Niño comes, the rise in water levels begins to occur faster, but with the change of phases almost every five years, a diametrically opposite phenomenon is observed. The strength of the effect of one or another phase also depends on other factors and clearly reflects the overall climate change towards its aggravation. Both phases of the southern oscillation are being studied by many scientists around the world, as they contain many clues to what is happening on Earth and what awaits her.
The atmospheric La Niña event of moderate to strong intensity will last in the tropical Pacific until April 2011. This is stated in the information bulletin on El Niño/La Niña, released on Monday by the World Meteorological Organization.
As emphasized in the document, all model-based forecasts predict the continuation or possible strengthening of the La Niña phenomenon over the next 4-6 months, ITAR-TASS reports.
La Niña, which formed in June-July this year, replacing the El Niño event that ended in April, is characterized by unusually low water temperatures in the central and eastern equatorial Pacific Ocean. It breaks normal routines tropical rainfall and atmospheric circulation. El Niño is just the opposite, characterized by an unusual high temperatures waters in the Pacific Ocean.
The effects of these phenomena can be felt in many parts of the planet, expressed in floods, storms, droughts, increases or, conversely, decreases in temperatures. La Niña typically results in heavy winter rainfall in the eastern equatorial Pacific, Indonesia, the Philippines, and severe droughts in Ecuador, northwestern Peru, and eastern equatorial Africa.
La Niña, which can increase in intensity and continue until the end of this year or the beginning of next year.
The latest report from the DoD on the El Niño and La Niña phenomena states that the current La Niña phenomenon will peak at the end of this year, but will be less intense than it was in the second half of 2010. Due to its uncertainty, the MoD invites the countries of the Pacific Ocean basin to closely monitor its development and promptly report possible droughts and floods due to it.
The La Niña phenomenon implies the phenomenon of an anomalous prolonged large-scale cooling of water in the eastern and central parts of the Pacific Ocean near the equator, which gives rise to a global climate anomaly. The previous La Niña event resulted in a spring drought on the West Pacific coast, including China.
The first time I heard the word "El Niño" in the US was in 1998. At that time, this natural phenomenon was well known to Americans, but almost unknown in our country. And not surprising, because. El Niño originates in the Pacific Ocean off the coast of South America and greatly affects the weather in the southern states of the United States. El Niño(translated from Spanish El Nino- baby, boy) in the terminology of climatologists - one of the phases of the so-called Southern Oscillation, i.e. fluctuations in the temperature of the surface layer of water in the equatorial part of the Pacific Ocean, during which the area of heated surface waters shifts to the east. (For reference: the opposite phase of the oscillation - the displacement of surface waters to the west - is called La Niña (La Nina- baby, girl)). Periodically occurring in the ocean, the El Niño phenomenon strongly affects the climate of the entire planet. One of the largest El Niño occurred just in 1997-1998. It was so strong that it attracted the attention of the world community and the press. At the same time, theories about the connection of the Southern Oscillation with global climate changes spread. According to experts, the warming phenomenon of El Niño is one of the main driving forces the natural variability of our climate.
In 2015 The World Meteorological Organization has reported that emerging ahead of schedule and dubbed "Bruce Lee" El Niño could be one of the most powerful since 1950. Its appearance was expected last year, based on data on the increase in air temperature, but these models did not justify themselves, and El Niño did not appear.
In early November, the American agency NOAA (National Oceanic and Atmospheric Administration) released a detailed report on the state of the Southern Oscillation and analyzed the possible development of El Niño in 2015-2016. The report is published on the NOAA website. In the conclusions this document It is said that at present there are all conditions for the formation of El Niño, the average surface temperature of the equatorial Pacific Ocean (SST) has increased values and continues to rise. The probability that El Niño will develop during the winter of 2015-2016 is 95% . A gradual decline in El Niño is predicted in the spring of 2016. The report published interesting chart, showing the change in SST since 1951. Blue areas correspond to lower temperatures (La Niña), orange Elevated temperatures shown (El Niño). The previous strong increase in SST by 2 °C was observed in 1998.
Data obtained in October 2015 suggest that the SST anomaly at the epicenter is already reaching 3°C.
Though Causes of El Niño not yet fully explored, it is known that it begins with the fact that the trade winds weaken over several months. A series of waves move along the Pacific Ocean along the equator and create a warm water mass near South America, where the ocean usually has low temperatures due to the rise of deep ocean waters to the surface. The weakening of the trade winds, taking into account the opposition to them by a strong west wind may also create a twin cyclone (south and north of the equator), which is another sign of a future El Niño.
Studying the causes of El Niño, geologists drew attention to the fact that the phenomenon occurs in the eastern part of the Pacific Ocean, where a powerful rift system has developed. The American researcher D. Walker found a clear connection between the increase in seismicity in the East Pacific Rise and El Niño. The Russian scientist G. Kochemasov saw another curious detail: the relief fields of oceanic warming almost one to one repeat the structure of the earth's core.
One of the interesting versions belongs to the Russian scientist - Doctor of Geological and Mineralogical Sciences Vladimir Syvorotkin. It was first mentioned back in 1998. According to the scientist, the most powerful centers of hydrogen-methane degassing are located in the hot spots of the ocean. And easier - sources of constant emission of gases from the bottom. Their visible signs- exits of thermal waters, black and white smokers. In the area of the coasts of Peru and Chile, during the years of El Niño, there is a massive release of hydrogen sulfide. Water boils, there is a terrible smell. At the same time, an amazing force is pumped into the atmosphere: approximately 450 million megawatts.
The El Niño phenomenon is now being studied and discussed more and more intensively. A group of researchers from the German national center geosciences came to the conclusion that mysterious disappearance Mayan civilization in Central America could be caused by strong climate change caused by El Niño. At the turn of the 9th and 10th centuries AD, at opposite ends of the earth, the two largest civilizations of that time almost simultaneously ceased to exist. We are talking about the Maya Indians and the fall of the Chinese Tang dynasty, followed by a period of internecine strife. Both civilizations were located in monsoonal regions, the moistening of which depends on the seasonal precipitation. However, the time has come when rainy season was unable to provide sufficient moisture for the development Agriculture. The drought and subsequent famine led to the decline of these civilizations, the researchers believe. Scientists came to these conclusions by studying the nature of sedimentary deposits in China and Mesoamerica related to the specified period. The last emperor of the Tang Dynasty died in 907 AD, and the last known Mayan calendar dates back to 903.
Climatologists and meteorologists say that El Niño2015, which will peak between November 2015 and January 2016, will be one of the strongest. El Niño will lead to large-scale disturbances in atmospheric circulation, which can cause droughts in traditionally wet regions and floods in dry ones.
A phenomenal phenomenon, which is considered one of the manifestations of the developing El Niño, is now observed in South America. The Atacama Desert, which is located in Chile and is one of the driest places on Earth, is covered with flowers.
This desert is rich in saltpeter, iodine, table salt and copper, for four centuries there was no significant precipitation. The reason is that Peruvian Current cools the lower layers of the atmosphere and creates temperature inversion which prevents precipitation. Rain falls here once every few decades. However, in 2015, the Atacama was hit by unusually heavy rainfall. As a result, dormant bulbs and rhizomes (horizontally growing underground roots) sprouted. The pale plains of the Atacama were covered with yellow, red, purple and white flowers - nolans, bomareys, rhodophials, fuchsias and mallows. The desert bloomed for the first time in March, after unexpectedly intense rains caused floods in the Atacama and killed about 40 people. Now the plants have bloomed for the second time in a year, before the beginning of the southern summer.
What will El Niño 2015 bring? A powerful El Niño is expected to bring long-awaited downpours to the arid regions of the United States. In other countries, the effect may be the opposite. In the Western Pacific, El Niño creates increased Atmosphere pressure bringing dry and sunny weather to vast areas of Australia, Indonesia, and sometimes even India. El Niño's impact on Russia has so far been limited. It is believed that under the influence of El Niño in October 1997 in Western Siberia the temperature was set above 20 degrees, and then they started talking about the retreat to the north of the permafrost. In August 2000, experts from the Ministry of Emergency Situations attributed the series of hurricanes and downpours that swept across the country to the influence of the El Niño phenomenon.
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