Walker Circulation explained in DETAIL | A Level Geography (2024)

Summary

In this video, the presenter discusses the Walker Circulation as part of a broader lesson on physical geography for A-level students. The Walker Circulation, a key atmospheric phenomenon in the Pacific Ocean, involves the movement of warm and cold ocean currents from the western to the eastern Pacific. The presenter explains how easterly trade winds cause warm water to accumulate in the west, while cold water upwells in the east, leading to dry conditions in South America and wet weather in Australia and Southeast Asia. The video also touches on how this process relates to El Niño and its potential impact on weather patterns.

Takeaways

• 😀 Walker circulation is a key concept in understanding the atmosphere and climate systems, particularly in the Pacific Ocean region.
• 😀 The Walker circulation involves the movement of warm ocean water from the eastern Pacific (near South America) to the western Pacific (near Australia) due to easterly trade winds.
• 😀 Trade winds blow from east to west, carrying warm water towards Indonesia and Australia, causing a low-pressure area in the western Pacific.
• 😀 In the eastern Pacific, cold nutrient-rich water rises to the surface along the coast of Peru and Chile due to upwelling, creating a high-pressure area.
• 😀 The western Pacific experiences wet weather due to intense convection caused by warm water and low pressure, leading to thunderstorms and rainfall.
• 😀 The eastern Pacific experiences dry conditions due to the high-pressure system, which is linked to cold ocean currents in the region.
• 😀 The key elements of the Walker circulation are trade winds, warm ocean water, cold upwelling water, and the resulting convection and pressure differences.
• 😀 Understanding the Walker circulation helps explain why regions like Chile and Peru often experience droughts while Australia and Indonesia face wet weather.
• 😀 Exam questions on Walker circulation may include diagram drawing, describing weather patterns, or evaluating impacts on regions like social and environmental factors.
• 😀 Key terms to remember for Walker circulation: trade winds, upwelling, convection, pressure systems (low and high), and their impact on weather patterns.

Q & A

What is the Walker Circulation?

The Walker Circulation refers to the movement of warm and cold ocean water and the atmosphere across the Pacific Ocean, affecting weather patterns in the surrounding regions. It involves the trade winds, ocean currents, and convection processes.

How do trade winds influence the Walker Circulation?

Trade winds blow from east to west across the Pacific Ocean, pushing warm ocean water towards the western Pacific. This leads to a region of low pressure in the western Pacific, driving convection and wet weather patterns.

What is the significance of the upwelling in the eastern Pacific?

Upwelling is the process where cold, nutrient-rich water from the ocean depths rises to the surface along the coast of Peru and Chile. It contributes to the dry conditions in the eastern Pacific by creating a high-pressure area.

What weather conditions are associated with the Walker Circulation in the western Pacific?

In the western Pacific, the warm ocean water creates a low-pressure zone, which leads to active convection and thunderstorms, resulting in wet weather conditions.

What weather conditions are associated with the Walker Circulation in the eastern Pacific?

In the eastern Pacific, cold ocean water creates a high-pressure area, leading to dry weather and potential droughts, particularly in areas like Peru and Chile.

What role does convection play in the Walker Circulation?

Convection occurs in the western Pacific due to the low pressure created by warm ocean waters. This results in the rising of warm air, which causes thunderstorms and wet weather patterns in that region.

How does the temperature difference between the western and eastern Pacific affect pressure systems?

The temperature difference causes low pressure in the warm western Pacific due to high temperatures and high pressure in the cold eastern Pacific. This creates a balance that drives the Walker Circulation.

What is the Peruvian Current and how does it relate to the Walker Circulation?

The Peruvian Current is a cold ocean current that flows along the coast of Peru and Chile. It contributes to the high-pressure system in the eastern Pacific, which results in dry conditions in that region.

How can the Walker Circulation impact the social and economic conditions of affected regions?

The Walker Circulation affects social and economic conditions by influencing agriculture, water availability, and overall climate. Wet conditions in the western Pacific can lead to flooding, while dry conditions in the eastern Pacific can cause droughts, affecting local economies.

What is the relationship between the Walker Circulation and El Niño?

El Niño is a phenomenon that disrupts the normal Walker Circulation. During El Niño, the weather patterns reverse, leading to wet conditions in the eastern Pacific and dry conditions in the western Pacific, causing significant changes in climate and weather systems.