RA

Chapter 4 Part 2: Weather and Weather Forecasting

The Atmosphere: An Ocean of Air

  • The atmosphere is a thin envelope of air surrounding our planet.
  • We live at the bottom of this "ocean of air."

Upper Air Troughs and Surface Weather

  • Upper Air Troughs: Elongated areas of low pressure in the upper atmosphere.
  • Upper air troughs play a crucial role in the formation of low-pressure systems at the surface.
  • Key Relationship: What occurs in the upper atmosphere directly influences surface weather conditions.

Divergence Aloft

  • Upper air troughs produce divergence at high altitudes.
  • Divergence: When more air is leaving an area than entering.
  • Divergence aloft contributes to lower surface pressure.