Blog Post #2: Getting to Know El Niño

Blog Post #2: Getting to Know El Niño

Background                              

El Niño events have been occurring for millennia, but it was not until the 1980s that El Niño and La Niña entered our vernacular. A strong El Niño event occurred in 1983 which spawned several notable storms in the eastern Pacific Ocean, impacting the West Coast of the United States. Another major El Niño event occurred in 1997-1998, causing storms, high surf, floods, and landslides across California.

While the effects of El Niño may be felt on both sides of the Pacific and across the United States, the geographic origins of El Niño can be traced to the eastern Pacific waters off the coast of Peru. El Niño develops when easterly trade winds weaken, slow, and sometimes reverse in the tropical waters of the Pacific Ocean. When this occurs, the typically cold waters off the coast of Peru begin to warm. Simultaneously, the typically warm waters in the western Pacific begin to cool. This “swapping” of sea-surface temperatures is known as the Southern Oscillation. Together with El Niño, the entire phenomenon is known as El Niño-Southern Oscillation (ENSO). The anomalous tropical Pacific sea-surface temperatures of ENSO may occur for up to a year.

This blog post is designed to explore the ocean-atmospheric phenomenon known as El Niño-Southern Oscillation (ENSO).

Resources

El Niño-Southern Oscillation (Links to an external site.)Links to an external site.: The interactive learning module explains the causes and effects of El Niño-Southern Oscillation. Explore the entire module, paying special attention to the Air-Sea Interactions and U.S. Regional Responses sections. (http://media.pearsoncmg.com/bc/bc_0media_geo/weather_animations/tutorials/final/11_enso.html (Links to an external site.)Links to an external site.)

National Geographic: El Niño and Peru (Links to an external site.)Links to an external site.: This video documents the ecological and economic impacts of El Niño events on the local economy of coastal Peru. (https://www.wiley.com/college/deblij/1118093607/videos/peru_el_nino/ (Links to an external site.)Links to an external site.)

Questions

Part 1

  1. Review the El Niño-Southern Oscillation (Links to an external site.)Links to an external site. learning module. In your own words, how would you describe the normal atmospheric and oceanic conditions of the tropical Pacific Ocean? What are the predominant normal wind patterns (east-to-west or west-to-east)? What is the normaldistribution of ocean temperatures?
  2. In your own words, what changes from normal conditions in the tropical Pacific Ocean (in terms of winds and distribution of ocean temperatures) occur during El Niño years? What changes from normal conditions occur during La Niña years?
  3. How do El Niño and La Niña events affect temperature and precipitation anomalies in the United States? How do they affect temperature and precipitation anomalies in coastal Southern California?

Part 2

  1. Watching the short National Geographic: El Niño and Peru (Links to an external site.)Links to an external site. What are the immediate ecological impacts of El Niño on Paracas National Reserve? How do the ecological impacts of El Niño affect the local economy?
  2. Synthesizing what you learned from the El Niño-Southern Oscillation learning module and National Geographic: El Niño and Peru video, how might El Niño and La Niña events impact the local ecologyin Southern California? Although the Southern California economy is not dependent on fishing, how else might El Niño and La Niña events impact the local Southern California economy?

Your response should be formulated in whole sentences and paragraphs. Proper punctuation, syntax, and writing mechanics must be followed. Be sure to define and explain any terms used. Make your explanations organized, clear, and detailed.