CONCEPTS OF METEOROLOGY (NSCI-170)

Project 2: Satellite-Image Interpretation (El Niño/La Niña)

Addresses course outcomes 1, 3, and 4

 critically evaluate weather data, including observations of natural weather phenomena, to make informed decisions in daily life  explain how climate change impacts weather  recognize the interrelationship between the atmosphere and other Earth systems to evaluate potential impacts

Background Information on El Nino and La Nina conditions:

Major changes in sea temperatures in the equatorial Pacific have been linked to natural oscillations in weather patterns across the Pacific Ocean, from the Americas to Australia, to as far away as the Asian monsoon area and east Africa. From the two figures below one can clearly observe that when sea surface temperatures in the eastern equatorial Pacific are warmer-than-normal then an El Niño event occurs. When sea surface temperatures “flip-flop” and become lower-than-normal, a La Nina event occurs..

Both "normal" (mean temperatures) conditions and "anomaly" conditions are depicted. Note how the "anomaly" displays help to better accentuate the El Niño or La Niña phenomenon that may be occurring. In the eastern tropical Pacific, El Niño shows warmer-than-normal sea surface temperatures, and La Niña shows cooler-than-normal sea surface temperatures. El Nino vs. La Nina maps across the equatorial Pacific Ocean

6/9/2011 3:52 PM

Normal, El Nino, and La Nina Conditions:

The following three charts show sea surface temperature (top) and wind conditions (bottom) over a span of several years. The long-term "seesaw effect" of surface atmospheric pressures across the tropical Pacific called the El Nino/Southern Oscillation (ENSO) helps produce the relaxing and strengthening of the trade winds, ultimately resulting in the cycle of “El Niño, La Niña, and normal”. The following figures display "wind" data and "sea surface temperature" data across the tropical Pacific Ocean for normal, El Nino, and La Nina conditions: Normal conditions:

El Niño conditions: La Niña conditions:

Sea Surface Height (SSH) Anomaly – June 2011

Source: Woods Hole Oceanographic Institution—Oceanus http://www.whoi.edu/oceanus/viewImage.do?id=83611&aid=53506 6/9/2011 3:52 PM Assignment Questions:

Just above is a satellite image displaying "sea surface height anomaly" (SSHA) across the tropical Pacific Ocean in 2011. Red over the eastern Pacific depicts higher-than- normal sea surface heights, and blue across the western Pacific depicts lower-than-normal sea surface heights. Based on your interpretation of the SSHA satellite image above, answer the following questions:

1) Based on the satellite imagery in 2011, how do sea surface height (SSH) and sea surface temperature (SST) relate to each other? 2) Do you think that either an El Niño or a La Niña condition was in effect at the time of the satellite image? Justify your answer. 3) Describe expected general weather conditions over Peru and Ecuador (eastern equatorial Pacific). 4) What would be the expected general fishing conditions off the coast of Peru and Ecuador? Explain why?

5) What would be the expected weather conditions across the southern USA (from California to the Carolinas), especially California? What natural hazards may intensify during this El Nino or La Nina event there?

6) What would be the expected weather conditions in Australia and Indonesia (western equatorial Pacific)? What natural hazards may intensify there during this El Nino or La Nina event?

7) What does the next year or so (2015-16) indicate from recent satellite monitoring of SSHA data. Check the course Webliography, scientific web sources, and the recent mainstream press news. View the Jason 2 satellite image and SST Pacific map on the next page for Question 7. For Question 7:

Satellite (Jason 2) image of Pacific Jan 15

Average sea surface temperature (SST) anomalies (C) for June 2015 (note red area)