ATM OCN (Meteorology) 100

THERMODYNAMICS:

BEHAVIOR OF GASES IN THE ATMOSPHERE

Summer 1999

Lecture # 6 Scheduled for:

22 JUN 1999 (T)

Recommended Readings from Moran and Morgan (1997):

pages 120-121; 136-138, 147-149 (skim).

Today's Lecture Objectives:

• To qualitatively apply the gas law (equation of state) to atmospheric processes.
• To explain an adiabatic process as it pertains to motions in the atmosphere.
• To determine the temperature changes experienced by a vertically moving air parcel using the adiabatic process lapse rate.
• To identify the various lifting processes operating with the atmosphere.
• To explain how atmospheric stability influences vertical motion of air.

Outline:

A. INTRODUCTION

• Practical Problems

B. KINETIC THEORY OF MATTER

• Definitions
• Historical
• Assumptions for gases
• Variables describing the molecular state of a gas
• Molecular Diffusion

C. THE GAS LAWS

• Classical approach to Ideal Gas Law (or Equation of State)
• Atmospheric application of Ideal Gas Law
• Dalton's Laws of Partial Pressures
• Atmospheric application of Dalton's Laws of Partial Pressures

D. THE THERMODYNAMIC LAWS

• Introduction
• First Law of Thermodynamics
• Atmospheric application of the First Law of Thermodynamics
• Adiabatic Processes

E. THE VERTICAL MOTION PROBLEM

• Response of an air parcel
• Specification of the parcel response - The adiabatic lapse rate

F. STATIC STABILITY

• Importance
• Stability - Instability Concept
• Response of the atmospheric environment
• Criteria for Static Stability (Instability) Determination
• Processes which change static stability (instability)
• Visual stability indicators
• Graphical Analysis: The Thermodynamic Diagram

Last revision 25 May 1999