Thermodynamic Chart (or Thermodynamic Diagram)

A chart containing contours of pressure, temperature, moisture, and potential temperature , all drawn relative to each other such that basic thermodynamic laws are satisfied. Such a chart typically is used to plot atmospheric soundings , and to estimate potential changes in temperature, moisture, etc. if air were displaced vertically from a given level. A thermodynamic chart thus is a useful tool in diagnosing atmospheric instability . (See sounding):