El Niño
What is El Niño?
El Niño is this complex weather phenomenon that occurs every 2 to 7 years in the Pacific and effects weather around the world.
How long does La Nina typically last?
Nine Months
What does ENSO stand for?
El Nino Southern Oscillation
Where did the name El Niño originate from?
The original name, "El Niño de Navidad", traces its origin centuries back to Peruvian fishermen, who named the weather phenomenon in reference to the newborn Christ.
Where did the name La Niña originate from?
"La Niña", chosen as the 'opposite' of El Niño, literally translates to "the girl"
What is the Walker circulation?
-The Walker circulation is caused by the pressure gradient force that results from a high pressure system over the eastern Pacific Ocean, and a low pressure system over Indonesia.
What are El Niño Conditions? (4 conditions)
- Warm ocean T in equatorial Pacific
- Walker Cell reverses
- Upwelling ceases
- Fewer nutrients and fewer fish
What season does La Niña begin to develop? When does it typically peak?
Develop in the spring, peak in the fall. Dissipates the next spring or early summer
What is a thermocline?
A steep temperature gradient in a body of water such as a lake, marked by a layer above and below which the water is at different temperatures
Name a few global effects of El Niño
Wet weather on the US Gulf Coast during winter, which is when it is usually dry
It causes a more active hurricane season in the Atlantic and less active hurricane season in the Pacific.
Temperature and precipitation changes
Usually followed by la nina events
During the Walker Circulation is La Nina known as the warm phase or the cool phase of the circulation?
Cool Phase
Differentiate Climate vs. Weather
Weather is the state of the atmosphere from day to day. It includes temperature, atmospheric pressure, clouds, wind, and precipitation. Climate is the long-term average of the weather.
Economic consequences of El Niño
A reduction of the fish population reduces the amount of fishmeal produced and exported (by local industry) to other countries for feeding poultry and livestock. If the world's fishmeal supply decreases, more expensive alternative feed sources must be used, resulting in an increase in poultry prices worldwide.
What happens during La Nina? (how it affects the different areas of the US)
- Southern and interior Alaska and the Pacific Northwest: cooler and wetter
- Southern tier of U.S. states (California to the Carolinas): warmer and drier
- North, the Ohio and Upper Mississippi River: wetter than usual
What is ITCZ?
The Inter Tropical Convergence Zone, or ITCZ, is a belt of low pressure which circles the Earth generally near the equator where the trade winds of the Northern and Southern Hemispheres come together. It is characterized by convective activity which generates often vigorous thunderstorms over large areas