The question
Name: ______________________ Date: ____________ Pacific sea surface temperature, trade winds and rainfall (10 points)
Data
Six years of observations across the tropical Pacific
| Winter | Sea surface temperature difference from average (°C) | Trade wind speed (m/s) | Rainfall at a coastal city in Peru (mm) | Rainfall at a city in Indonesia (mm) |
|---|---|---|---|---|
| 1 | +0.1 | 6.0 | 20 | 900 |
| 2 | +2.1 | 2.5 | 410 | 380 |
| 3 | -1.4 | 8.1 | 5 | 1,250 |
| 4 | -0.2 | 6.3 | 15 | 950 |
| 5 | +1.2 | 3.9 | 180 | 560 |
| 6 | -0.9 | 7.4 | 8 | 1,100 |
(a) Scientists recorded conditions across the tropical Pacific for six winters, shown in the table. Identify the winter with the weakest trade winds, and give its trade wind speed. [1 point]
(b) Describe the relationship between trade wind speed and the sea surface temperature difference shown in the data. Use numbers from the table in your answer. [2 points]
(c) Calculate the percent change in rainfall at the Indonesian city from winter 1 to winter 2. Show your setup and give the answer with units. [2 points]
(d) Identify the winter that best shows La Niña conditions, and justify your answer with data from the table. [1 point]
(e) Explain why rainfall at the coastal city in Peru was so much higher in winter 2 than in winter 1. [2 points]
(f) Coastal Peru has one of the world's largest anchovy fisheries. Describe one effect of conditions like winter 2 on this fishery, and explain how the change in the ocean causes it. [2 points]