Global Wind Patterns: Diagram illustrating prevailing winds, trade routes, and convection currents on a motionless planet, highlighting the impact of Earth's rotation on wind patterns.

You’ve uploaded a worksheet titled “Global Wind Patterns” that explains how prevailing winds influenced historical navigation (especially Columbus’s voyages) and the science behind wind formation via convection. Let’s go through each question and provide a clear, accurate explanation — even though you’ve already filled in some answers, we’ll verify and expand on them.

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Question 1: Why did Columbus sail south along Africa before he sailed west to the Americas?

✔ Answer:
He needed to reach the Northeast Trade Winds.

🔹 Explanation:
Columbus understood that at about 20°N latitude, there are consistent northeast trade winds that blow steadily from the northeast toward the southwest — perfect for sailing westward across the Atlantic Ocean to the Americas. To catch these favorable winds, he first sailed south along the coast of Africa (from Spain/Portugal) to reach that latitude zone. Once he reached ~20°N, he turned west and let the trade winds carry his ships efficiently across the ocean.

This was a clever navigational strategy based on early understanding of global wind patterns — long before modern weather forecasting!

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Question 2: What do we call winds from the most common wind direction?

✔ Answer:
Prevailing winds

🔹 Explanation:
“Prevailing winds” are the dominant, most frequently occurring winds in a particular region or latitude belt over time. For example:
- The Trade Winds (NE in N. Hemisphere, SE in S. Hemisphere)
- The Westerlies (blow from west to east in mid-latitudes)
- The Polar Easterlies (blow from east near poles)

These are not random — they’re part of Earth’s global atmospheric circulation system driven by solar heating and the Coriolis effect.

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Question 3: Winds are heat flow by ________.

✔ Answer:
Convection

🔹 Explanation:
Wind is essentially air in motion, and this motion is caused by differences in air temperature and pressure — which result from uneven heating of Earth’s surface by the sun.

This process is called convection:
→ Warm air rises (less dense)
→ Cool air sinks (more dense)
→ This creates circulation cells (like Hadley, Ferrel, Polar cells)
→ Air moves horizontally to replace rising/sinking air → wind!

The diagram labeled “Convection on a Motionless Planet” shows this simple model — but Earth rotates, so the Coriolis effect bends the wind paths, creating the complex patterns we see today.

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✔ Final Answers Summary:

1. He needed to get to the NE trade winds — to use them for efficient westward travel across the Atlantic.
2. Prevailing winds — the most common, dominant wind direction in a region.
3. Convection — the transfer of heat through the movement of fluids (like air), which drives wind.

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Let me know if you’d like help with pages 2–4 of this worksheet too! 🌍🌀