Subtropical jet stream

Definition

The subtropical jet stream is a fast-flowing ribbon of air located in the upper troposphere, typically found at latitudes around 20 to 30 degrees north and south of the equator. It plays a crucial role in influencing weather patterns by separating tropical and polar air masses, contributing to the development of mid-latitude weather systems, and affecting the distribution of moisture and heat in the atmosphere.

5 Must Know Facts For Your Next Test

1. The subtropical jet stream is typically stronger during winter months due to increased temperature gradients between the tropics and polar regions.
2. It can influence weather events like droughts or heavy rainfall by steering storm systems and altering their paths across continents.
3. Variations in the position of the subtropical jet can lead to significant differences in regional climates, such as shifting precipitation patterns.
4. The subtropical jet stream can interact with the polar jet stream, leading to complex weather phenomena like cut-off lows and enhanced storm development.
5. Changes in climate can affect the strength and position of the subtropical jet stream, potentially impacting global weather patterns.

Review Questions

• How does the subtropical jet stream interact with other atmospheric circulation patterns, such as Hadley cells?
  • The subtropical jet stream is closely linked to Hadley cells, which create an environment where warm air rises near the equator and moves toward higher latitudes. As this air cools, it descends around 30 degrees latitude, forming a region of high pressure. The movement of this descending air contributes to the formation and positioning of the subtropical jet stream. Thus, interactions between these two systems play a key role in shaping global weather patterns.
• Discuss how variations in the subtropical jet stream can lead to extreme weather conditions across different regions.
  • When the position or strength of the subtropical jet stream changes, it can significantly impact regional weather. For example, a southward shift might result in increased rainfall or storms in areas that are usually dry, while a northward shift can lead to drought conditions. These shifts can alter moisture transport and temperature distribution, leading to various extreme weather events such as heatwaves or heavy precipitation.
• Evaluate the potential impacts of climate change on the behavior of the subtropical jet stream and its implications for global weather patterns.
  • Climate change is likely to influence the subtropical jet stream by altering temperature gradients between tropical and polar regions. As temperatures rise globally, this may weaken or shift the jet stream's position, resulting in changes to storm tracks and regional climates. Such alterations could exacerbate existing weather extremes, making some areas more prone to flooding while others may face increased drought risk. Understanding these potential impacts is crucial for predicting future weather patterns as climate change progresses.

Related terms

polar jet stream:

A fast-moving river of air in the upper troposphere that typically exists at higher latitudes than the subtropical jet stream, primarily influencing weather patterns in the mid-latitudes.

Hadley cell: A large-scale atmospheric circulation pattern where warm air rises at the equator, moves towards higher latitudes, cools, and then sinks around 30 degrees latitude, contributing to the formation of the subtropical jet stream.

Rossby waves: Large-scale meanders in high-altitude winds that affect weather patterns by transporting warm and cold air masses, often influenced by the positions of both the subtropical and polar jet streams.