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El Nino. La Nina. &. By:John-Paul Aleo&Kory Martyniuk. Table Of Contents. Recent Occurrences Of El Nino & La Nina. What Is El Nino & La Nina?. Slide 8. Slide 1. What Causes El Nino?. Potential For Destruction. Slide 2. Slide 9. What Causes La Nina?. Slide 3.
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El Nino La Nina & By:John-Paul Aleo&Kory Martyniuk
Table Of Contents Recent Occurrences Of El Nino & La Nina What Is El Nino & La Nina? Slide 8 Slide 1 What Causes El Nino? Potential For Destruction Slide 2 Slide 9 What Causes La Nina? Slide 3 Potential For Destruction Continued… Slide 10 Time Of The Year It Occurs & How Often Slide 4 Slide 11 Other Info Where El Ninos & La Ninas Occur Slide 5 Other Info Continued… Slide 12 Slide 6 El Nino In Our Area La Nina In Our Area Slide 7
El Niño refers to a pattern characterized by the tropical Pacific’s warmest water spreading eastward to the coast of South America. • The opposite condition which is called La Nina is characterized by unusually cold ocean temperatures in the tropical Pacific. What Is El Nino & La Nina
Trade winds blow in a westerly direction along the equator. These winds pile up warm surface water in the western Pacific, so the sea surface is higher in the western Pacific than in the eastern Pacific. • These trade winds are one of the main sources of fuel for the Humboldt Current. This cold ocean current which flows north along the coasts of Chile and Peru, then turns west and warms as it moves out into the Central Pacific. So, the normal situation is warmer water in the western Pacific, cooler in the eastern. What Causes El Nino In Non-El Nino Conditions El Nino Conditions • the equatorial westerly winds diminish. As a result, the Humboldt Current weakens and this allows the waters along the coast of Chile and Peru to warm and creates warmer than usual conditions along the coast of South America.
What Causes La Nina Typically, a La Niña is preceded by a buildup of coolerthannormal subsurface waters in the tropical Pacific. Eastward-moving atmospheric and oceanic waves help bring the cold water to the surface through a complex series of events. In time, the easterly trade winds strengthen, cold upwelling off Peru and Ecuador intensifies, and sea-surface temperatures drop below normal.
What Time Of The Year It Occurs How Often This Weather Event Occurs & • Extreme El Ninos event could occur once every 20 to 50 years. • Both La Niña and El Niñq tend to peak during the Northern Hemisphere winter. • El Nino mostly occurs in our winters, and La Nina occurs during our summers. • La Niña conditions typically last approximately 9-12 months. Some episodes may last for as long as two years. • El Nino events usually begin early in the year (between January and March) and often peek during the month of December. • They may only happen for a few months, or more often they occur for 1 or 2 years. • Usually happen every 3-5 years.
Where Are El Ninos and La Ninas Most Likely To Happen? Where Is It Least Likely To Happen? • El Nino & La Nina is most common to occur between the tropical and equatorial Pacific Ocean but leaves many effects all over the world. Places such as South and North America, Africa, and Australlia. • El Nino and La Nina have a big impact on Peru and Ecuador.
Events Of El Nino In Our Area 1997-98 Ice Storm In 98 • The ice storm of January 1998 was the worst ever to hit Canada, based on the the amount of ice accumulationn, the duration of the storm, and the population affected. • The areas affected by the storm were eastern Ontario, southern Québec, and most of the east coast. • During the six days of the storm, January 4-10, the water equivalent of freezing rain and ice pellets exceeded 100 mm in many areas, more than double the yearly average. • A record warm February helped to produce the warmest 1997-99 winter in 66 years in southern Ontario. With the temperatures 6 degrees Celsius above normal
Events Of La Nina In Our Area • Inclement winter weather continued into March 1996. On the 20th, which is the first day of spring,one of the winter's strongest snow storms hit southern Ontario. Accompanied by high winds and thunderstorms, this storm brought traffic to a virtual standstill in areas outside of Toronto. In Windsor, where ice buildups also occurred, the storm was the worst in the previous five years. The cost of snow removal was $250,000, ¼ of the city's annual snow-removal budget.
Recent Occurances Of El Nino & La Nina • Recent years in which El Niño events have occurred are 1951, 1953, 1957-1958, 1965, 1969, 1972-1973, 1976, 1982-1983, 1986-1987, 1991-1992, 1994 and 1997. • The El Niño of 1982-83 was responsible for the loss of nearly 2,000 lives and displacement of hundreds of thousands from their homes. The losses were caused by droughts, forest fires, and floods. • La Niñas occurred in 1904, 1908, 1910, 1916, 1924, 1928, 1938, 1950, 1955, 1964, 1970, 1973, 1975, 1988, 1995
Potential For Destruction • Because El Niño's warm pool feeds thunderstorms above, it creates increased rainfall across the east-central and eastern Pacific Ocean. • The effects during the months of February, March and April may become critical in Southern Brazil and Argentina also experience wetter than normal conditions but mainly during the spring and early summer. • An El Niño is associated with warm and very wet summers in (december through febuary) along the coasts of northern Puru and Ecuador causing major flooding whenever the event is strong or extreme. • Chile receives a mild winter with large rainfall • Drier and hotter weather occurs in parts the Amazon River, Colombia and Central America.
Potential For Destruction Continued.... • Direct effects of El Niño resulting in drier conditions occur in Indonesia, the Philippines, and northern Australia • Summer is wetter in themountain regions of the U.S. • During a La Niña, by contrast, the midwestern U.S. tends to be drier than normal. • In North America, typically, winters are warmer than normal in the upper midwest states and Canada. • Africa experiences wetter than normal conditions near the equator. • There also are drier than normal conditions in south-central Africa
Other Information About El Nino & La Nina • The name comes from Spanish name for the Christchild; the name was given by a fishermen working off the coast of Peru and Ecuador, who noticed it often occurs around Christmas. • A new El Niño has been in effect since September 2004 • La Niña means The Little Girl. La Niña is sometimes called El Viejo (Old Man), anti-El Niño, or simply "a cold event"
Other Information About El Nino & La Nina Continued..... • The relationship between the earths rotation, the coriolis force, and El Nino & La Nina? • El Nino results in a decrease in the earth's rotation rate, an increase in the length of day, and therefore a decrease in the the strength of the Coriolis force. La Nina tends to have the opposite effect. • In the tropical Pacific Ocean, El Ninos are detected by many methods such as satellites, drifting buoys, and sea level analysis.
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