Assignment

There are five parts to this assignment: Introduction, 3 body sections, and a conclusion. We will focus on the 3 body sections first and complete the intro and conclusion last. Each section of your paper must have a subtitle.

I) Introduction: What is the purpose of this essay? Then write a short statement about each of the three body paragraphs to describe what will be discussed there.

II) El Nino vs. La Nina: In the first body paragraph, provide a general description of what El Niño and La Niña are. Use your textbook as a primary reference. Using the image (Figure 1), make sure to describe the sea surface temperature anomaly (comparison of sea surface temperature under an El Niño/La Niña condition to the normal condition). Make sure to refer to Figure 1.

III) Sea Surface Temperatures and Atmospheric Circulation:

The sea surface temperature changes during El Niño/La Niña events are associated with changes in atmospheric circulations (Figure 2)

Compared to the normal circulation condition , identify regions where major circulation change occurs (hint: look at where the greatest cloud buildup occurs).

a) It would be a good idea to first characterize the normal conditions (Walker Circulation) seen in top image frame of Figure 2.

b) How have the atmospheric and ocean circulation dynamics changed during Nino and Nina? Alteration in Trade Winds and Ocean circulation - Figure 2

1. Reduction in the strength of the Northeast Trade Winds Eastern Pacific Ocean during NH winter along equatorial west coast of South America compared to western portion of Pacific Ocean.

a) During El Nino there is a transfer of warm water from western to eastern Pacific ocean due to higher sea level on western side of Pacific near northern Australian east coast.

2. La Nina - Exaggerated version of the Walker Circulation -

Enhanced Normal Trade Winds, Colder Eastern Pacific Water and Warmer Western Pacific Water = Dry SA and Wet Australia

3. Changes from normal Walker Circulation to Nino and Nina.

c) What is the relationship between sea surface temperature change and the location of rising and sinking air? Figure 2

1. Warmer Surface Temperature = Potentially less stable atmosphere and more rising air - Lower Pressure

2. Cooler Surface Temperatures = Potentially more stable atmosphere and more sinking air. Higher Pressure

3. Identify where increased sinking air is occurring and where rising air is occurring - Figure 2

a. During El Nino air is rising along west coastal equatorial South America.

b. During La Nina air is sinking along west coastal equatorial South America.

4. What is the association with the shift of warmer/colder sea surface temperatures and rising branch of air and sinking branch of air? Figure 2

a. Warmer than normal water (SA) creates lower surface atmospheric pressure.

b. Cooler than normal water (N. Australia) creates higher than normal atmospheric pressure.

5. What typically happens with the regions of rising branch of air and sinking branch of air? Figure 2

a. Rising = More than normal precipitation - Eastern Pacific (West SA)

b. Sinking = Below normal precipitation - Western Pacific (Eastern Australia)

c. Walker Circulation vs. El Nino and La Nina

IV) In the final body paragraph, refer to (Figure 3).

Try to describe what North American regions are experiencing warmer or cooler conditions along with which North American locations are experiencing wetter or drier conditions during El Nino and La Nina conditions.

V) Conclusion : You want to focus on summarizing what was discussed by reducing each paragraph to its essential take-away message.

Attachment:- Writing-Assignment.pdf