Westerlies are prevailing winds that blow from the west towards the east in the middle latitudes of the Earth, roughly between 30° and 60° latitude north and south of the equator. They play a significant role in shaping regional climate patterns and are a key factor in the global atmospheric circulation.
Characteristics
- Westerlies blow from the west towards the east, driven by the rotation of the Earth and the pressure gradient between the equator and the poles.
- They are strongest in the upper atmosphere and weaken as they descend to the surface.
- Westerlies are more pronounced in the Southern Hemisphere, where they are known as the “Roaring Forties” and “Furious Fifties” due to their intensity.
Impact on Climate
- Westerlies influence the distribution of heat and moisture around the globe, contributing to regional climate patterns.
- They play a significant role in shaping the climate of mid-latitude regions, including Western Europe and North America.
Weather Patterns
- Westerlies are associated with various weather patterns, including low-pressure systems, fronts, and storms.
- They can bring rain and storms to regions like Western Europe and the western coasts of North America.
Examples
- The Roaring Forties in the Southern Hemisphere are known for their strong westerly winds, which have been a challenge for sailors and navigators throughout history.
- The westerlies in the North Atlantic influence the climate of Western Europe, bringing mild winters and cool summers to the region.
In summary, westerlies are a significant component of the global atmospheric circulation system, playing a crucial role in shaping regional climate patterns and influencing weather events in mid-latitude regions.