CZ_7._KAP_Global_atmospheric_movement_notes

Climate & Weather Day 7

Important Key Vocabulary

• Air Pressure: The weight of air exerted on a surface, crucial in understanding weather systems as it influences wind and precipitation patterns.

• Wind: The movement of air from areas of high pressure to areas of low pressure, primarily driven by temperature variations in the atmosphere.

• Coriolis Effect: The phenomenon that describes how moving objects, including air, are deflected to the right in the Northern Hemisphere and to the left in the Southern Hemisphere due to Earth’s rotation, significantly affecting wind patterns.

• Wind Belt: Distinct regions of the Earth characterized by consistent patterns of wind, influenced by temperature gradients and the Coriolis effect.

• Jet Stream: Fast-moving air currents found in the upper atmosphere, acting as a major player in the movement of weather systems and influencing climate across different regions.

Review of Coriolis Lab

Questions to Consider

• Analyze the direction of airflow in high and low pressure systems and how they affect local weather.

• Investigate the influences of Earth’s rotation on global wind patterns and the implications for climate.

• Deepen understanding of the Coriolis Effect and its importance in meteorology.

Global Patterns of Atmospheric Movement

Atmospheric Pressure:

• Definition: A crucial measurement that reflects the force exerted by the atmosphere on a specific surface area. Atmospheric pressure can impact weather by influencing wind patterns and storm development.

• Isobars: Lines on weather maps that connect points of equal atmospheric pressure, providing a visual representation of pressure systems and aiding in weather prediction.

High Pressure vs. Low Pressure

• High Pressure:

  • Characteristics: Typically associated with sinking air which creates clear, stable weather conditions. High pressure zones are often cooler and have a denser atmosphere that feels weighty, leading to fewer clouds and precipitation.

• Low Pressure:

  • Characteristics: Associated with rising air, often leading to cloud formation and precipitation. Low pressure areas are typically warmer, less dense, and can be indicative of storm development.

Mechanism of Wind Formation

• Wind formation is driven by thermal dynamics:

  1. Warm air rises, creating a region of lower pressure.

  2. Conversely, cooler air sinks, resulting in high pressure.

• The interplay between these zones results in wind flow directed from areas of high pressure to low pressure, which is fundamental to weather phenomena.

• Remember: "From HIGH to LOW the winds will blow."

Global Wind Patterns

Coriolis Effect and Wind Belts

• The Coriolis Effect significantly influences large-scale wind patterns, causing global winds to curve rather than flow straight.

• Wind Belts include defined regions at various latitudes:

  • Doldrums: Characterized by calms and light winds at the equator, where the trade winds meet.

  • Horse Latitudes: Calm zones located at about 30 degrees latitude, north and south, known for their calm weather and high pressure.

  • Polar Easterlies: Cold winds that blow away from the polar regions, resulting in distinct cold weather patterns.

  • Prevailing Westerlies: Winds that flow from west to east in the mid-latitudes, crucial for determining storm tracks.

  • Trade Winds: These winds blow from the horse latitudes toward the equator, facilitating intertropical weather patterns.

Jet Stream

• The Jet Stream is a narrow band of strong winds located at high altitudes that play a significant role in global weather patterns by influencing storm paths and temperature distributions across continents.

Climate Phenomena: El Niño and La Niña

• El Niño: A climate pattern characterized by warmer-than-average Pacific surface temperatures, often leading to weaker trade winds and less rainfall in some regions, but excessive rainfall in others, impacting agriculture and ecosystems.

• La Niña: The counterpart to El Niño, marked by cooler-than-average Pacific surface temperatures and stronger trade winds, typically resulting in increased rainfall in certain regions and droughts in others, affecting global weather patterns.

Summary of Global Patterns of Atmospheric Movement

• Variations in air pressure are the driving force behind wind formation, shaping weather patterns across the globe.

• It is essential to understand how the Coriolis Effect and jet streams influence global wind patterns, as these are fundamental concepts in meteorology.

Diagram of Radiation, Conduction, and Convection

This diagram represents the sequence of events that lead to the formation of air and ocean currents:

1. Radiation: The Sun heats the land and water, driving temperature differences.

2. Conduction: The land heats the air directly above it, increasing its temperature.

3. Convection: Rising heated air creates convection currents, creating wind.

• Result: Wind patterns contribute to ocean currents, playing a significant role in climate regulation.

Diagrams

Diagram illustrating atmospheric pressure systemsDiagram of the Jet Stream and its influence on weather patternsIllustration of the Coriolis Effect on global winds

Diagram of radiation, conduction, and convection processes

Note: Replace the example URLs with actual links to the diagrams you wish to include.