What happens during el nino southern oscillation?

The El Niño Southern Oscillation (ENSO) is a periodic shift of the ocean-atmosphere system in the tropical Pacific that impacts weather around the world. It happens every 3-7 years (5 years on average) and typically lasts nine months to two years. It is associated with floods, droughts, and other global disturbances.

How does Southern Oscillation cause El Niño?

What causes an El Niño event? In a normal year, when ENSO is inactive, the equatorial Pacific trade winds blow from east to west. The winds push the warmer water towards the west, and colder water rises up from deeper in the ocean to replace it.

What does El Niño do to the southern hemisphere?

El Niño years tend to see warmer-than-average temperatures across most of southern Australia, particularly during the second half of the year. In general, decreased cloud cover results in warmer-than-average daytime temperatures, particularly in the spring and summer months.

What changes are caused by the El Niño Southern Oscillation in the Pacific Ocean quizlet?

During an El Nino unusually high atmospheric sea level pressures develop in the western Pacific and Indian Ocean regions and unusually low sea level atmospheric pressures develop in the southeastern tropical Pacific due to deterioration or shut down of the Southeast Trade Winds, which allows the warm, low pressure, …

What happens to the ocean during ENSO?

This in turn slows the ocean current that draws surface water away from the western coast of South America and reduces the upwelling of cold, nutrient–rich water from the deeper ocean, flattening out the thermocline and allowing warm surface water to buld in the eastern part of the basin.

What are the effects of El Niño in the Pacific Northwest?

The effects of a strong El Nino include a wetter and cooler than normal winter season in the southern United States, though the Pacific Northwest states tend to be warmer. Along the equatorial Pacific, conditions tend to warmer and wetter. Parts of southern Africa tend to be drier and warmer along with southeast Asia.

How does El Niño affect South America?

El Niño has been brewing in the Pacific since May 2015, affecting Latin American countries severely. Its more notable consequences include droughts, affecting Colombia, Venezuela, Mexico and Central America, strong rainfall in Argentina, Northern Peru and Southern Chile and the increase of wildfires in areas of Brazil.

What effects are there on Pacific sea life and productivity during El Niño?

An El Niño reduces the upwelling of cold water off the coast of the Americas. When this happens, fish either die or migrate into areas where they’ll find more to eat. With the fish gone, sea birds that depend on them may die or go elsewhere. Kelp forests are often destroyed by storms and ocean swells.

What happens during El Nino Southern Oscillation quizlet?

El Nino Southern Oscillation, trade winds weaken &amp, warm surface water moves toward South America. Diminished fisheries off South America, drought in western Pacific, increased precipitation in southwestern North America, fewer Atlantic hurricanes.

What happens in the tropical Pacific Ocean during an El Niño event?

During an El Niño event, the surface waters in the central and eastern Pacific Ocean become significantly warmer than usual. That change is intimately tied to the atmosphere and to the winds blowing over the vast Pacific.

What changes are caused by the Southern Oscillation in the Pacific Ocean quizlet?

Southern Oscillation is the accompanying atmospheric component, coupled with the sea temperature change: –El Niño is accompanied with high, and La Niña with low air surface pressure in the tropical western Pacific. -The two periods last several years each (typically three to four) and their effects vary in intensity.

What is El Niño in relation to ocean oscillations?

El Niño–Southern Oscillation (ENSO) is an irregular periodic variation in winds and sea surface temperatures over the tropical eastern Pacific Ocean, affecting the climate of much of the tropics and subtropics. The warming phase of the sea temperature is known as El Niño and the cooling phase as La Niña.

What exactly does the oscillation in Southern Oscillation refer to?

Southern Oscillation, in oceanography and climatology, a coherent interannual fluctuation of atmospheric pressure over the tropical Indo-Pacific region. The Southern Oscillation is the atmospheric component of a single large-scale coupled interaction called the El Niño/Southern Oscillation (ENSO).

What happens to atmospheric and oceanic circulation in the tropical Pacific during an ENSO event?

El Niño and Southern Oscillation are abbreviated as ENSO. During El Niño, changes in atmospheric circulation over the tropical Pacific are accompanied by changes in ocean currents and sea-surface temperature (SST) patterns. The pool of warm surface water normally driven westward by the trade winds now drifts eastward.

What are the effects of El Niño in California and across the southern states?

In general, the effect of El Niño on California is increased rainfall with accompanying floods, landslides, and coastal erosion. The effects are variable across the state and are more predictable in Southern California. Diminished upwelling of cold, nutrient-rich water upon which phytoplankton depend.

What is the effect of El Niño on both Pacific hurricanes or typhoons and Atlantic hurricanes?

In addition to enhanced vertical wind shear, El Niño suppresses Atlantic hurricane activity by increasing the amount of sinking motion and increasing the atmospheric stability. La Niña has opposite impacts across the Pacific and Atlantic basins.

What effect does an El Niño event have on the western USA?

Generally speaking El Niño brings: cooler and wetter weather to the southern United States. warmer weather to western Canada and southern Alaska. drier weather to the Pacific Northwest.

What does El Niño bring to South America?

El Niño is a weather pattern that occurs in the Pacific Ocean. During this time, unusual winds cause warm surface water from the equator to move east, toward Central and South America. El Niño can cause more rain than usual in South and Central America and in the United States.

How does El Niño affect Middle and South America?

The impacts may be significant at regional levels. In Central America, El Niño leads to excessive rainfall along the Caribbean coasts, while the Pacific coasts will remain dry. Rainfall increases on the coasts of Ecuador, the northern part of Peru, and southern zones of Chile.

How does El Niño affect Australia and South America?

During an El Nino, it is likely to see reduced rainfall and warmer temperatures in Australia and Indonesia. … During an el nino, the trade winds that typically bring warm ocean temperatures to the west, will likely be reversed, bringing the warm ocean temperatures to the East, along the coast of South America.

What are the effects of El Niño on the environment?

In general, El Nino causes global temperatures to rise. However, some areas can experience extreme and unusual cold weather. Depending on one’s location, El Nino can lead to unusually warm and dry winters, or extremely cold and wet winters.

What effects do El Niño and La Niña have on weather and where do these effects occur?

For example, in the Southern United States, during the fall through spring, El Niño usually causes increased rainfall and sometimes destructive flooding. La Niña, however, usually causes drier weather in the South, but the Northwest tends to be colder and wetter than average.

How does El Niño affect the economies of Ecuador and Peru?

Rainfall increases drastically in Ecuador and northern Peru, contributing to coastal flooding and erosion. Rains and floods may destroy homes, schools, hospitals, and businesses. They also limit transportation and destroy crops. As El Niño brings rain to South America, it brings droughts to Indonesia and Australia.

What is the cause of El Niño events quizlet?

is an abnormal weather pattern that is caused by the warming of the Pacific Ocean near the equator, off the coast of South America.

What is an El Niño event quizlet?

El Nino. (oceanography) a warm ocean current that flows along the equator from the date line and south off the coast of Ecuador at Christmas time. La Nina. A cooling of the ocean surface off the western coast of South America, occurring periodically every 4 to 12 years and affecting Pacific and other weather patterns.

What do El Niño mean?

El Niño means Little Boy, or Christ Child in Spanish. South American fishermen first noticed periods of unusually warm water in the Pacific Ocean in the 1600s. The full name they used was El Niño de Navidad, because El Niño typically peaks around December. El Niño can affect our weather significantly.

What is Southern Oscillation in geography class 9?

Southern oscillation refers to shifting the surface air pressure between the tropical eastern Pacific and eastern Indian oceans.

How does El Niño affect the water cycle?

During El Niño periods, reduced precipitation in these regions leads to lower terrestrial moisture content, so there is less water in the soil available to evaporate. These regional reductions are so intense that they severely affect the global average volume of evapotranspiration.

What is the Southern Oscillation quizlet?

Southern oscillation. the periodic change in the pressure differential between the Southeastern Pacific high pressure and the Western Pacific equatorial low pressure that occurs in concert with the El-Nino-Southern Oscillation events.

What is the Southern Oscillation and how is it related to El Niño and La Niña?

El Niño and La Niña are the warm and cool phases of a recurring climate pattern across the tropical Pacific—the El Niño-Southern Oscillation, or “ENSO” for short. The pattern shifts back and forth irregularly every two to seven years, and each phase triggers predictable disruptions of temperature, precipitation.

How do El Niño and Southern Oscillation control the climate of India?

As those conditions change, with the monsoon being linked to El Nino-Southern Oscillation phenomena, summer temperatures over much of India may rise to as high as 45 degrees Celsius, while the Indian Ocean is much cooler.

What are weather oscillations?

A shift in position of various high and low pressure systems that in climate terms is usually defined as an index (i.e., a single numerically-derived number, that represents the distribution of temperature and pressure over a wide ocean area, such as the El Niño-Southern Oscillation, North Atlantic Oscillation, and …

What causes climate oscillations?

Climate oscillations are the naturally reoccurring changes of earth’s climate that are associated with the interactions of atmospheric and oceanic conditions and occur over different geographic scales and time periods.

How does Southern Oscillation occur?

These motions – rising in the west, sinking in the east – are connected through easterly Trade Winds near the surface and a westerly wind aloft, forming the Walker Circulation. Fluctuations in the position and intensity of the Walker Circulation cause the Southern Oscillation.

What is the relationship between the Southern Oscillation and the Walker cell?

These motions – rising in the west, sinking in the east – are connected through easterly trade winds near the surface and a westerly wind aloft, forming the Walker Circulation. Fluctuations in the position and intensity of the Walker Circulation cause the Southern Oscillation.

What relationship is there between El Niño and North Atlantic hurricanes La Niña and North Atlantic hurricanes?

El Niño events generally suppress Atlantic hurricane activity so fewer hurricanes than normal form in the Atlantic during August to October, the peak of Atlantic hurricane season. During La Niña, westerly winds high in the atmosphere weaken.

Why does an El Niño or La Niña event affect the Atlantic hurricane season?

La Niña’s impact on the rest of hurricane season

During La Niña, weaker winds between the ocean surface and upper levels of the atmosphere impact global jet streams and can influence the track and severity of winter storms and hurricanes during warmer months.

How does El Niño affect the number of hurricanes in the Atlantic ocean?

If El Niño has a strong presence, or makes Pacific waters warmer than usual, it increases the amount of “wind shear” across the the Atlantic basin. Wind shear is bad for hurricanes, and tropical storm production. It disrupts necessary conditions for tropical storms to form.