Jon Ahlquist10/4/2006MET1010 Intro to the Atmosphere1Chapter 6: Stabilityand Cloud DevelopmentComments on chapterDefinition of stabilityBuoyancy forceVertical stability in atmosphereLapse rate and stabilityStability and cloudsChanging cloud formsDetermining the height of the cloud baseComments on chapter 6In this chapter, hard concepts are mixed in with straightforward concepts.Be guided by these notes and my review questions as to what to learn. I don’t expect you to know too many things from this chapter. Just strengthen the concepts presented in these notes.If you want to be a meteorology major, you’ll ultimately need to understand everything in this chapter, so it won’t hurt to get started now.Only about 6-8 exam questions for exam 3 will come from this chapter.Classical Definition of Stability (p. 140)Something at rest is in equilibrium. Give something at rest a small push. Then see whether there is a force on the object. The equilibrium is:Stableif a force pushes it back toward its initial positionUnstableif a force pushes it further away from its initial positionNeutrally (un)stableif there is no push either toward or away from its initial position (ball on flat surface, not pictured)Fig 6.1,p. 140Stability: Psychology ExampleApply the preceding stability definitions to psychology. If you experience a small disturbance in life, you would be:stableif you adjust back to the way you were before the incidentunstableif the small disturbance becomes a big deal in your lifeneutrally stableif you don’t go back to the way you were nor do you become more extreme(“go with the flow”)Buoyancy Force (not in book)A “fluid” is anything that can flow. Liquids (like water) and gases (like air) are both fluids.An object in a fluid has at least 3 vertical forces pushing on it:(1) the force of gravity pulling it down,(2) the pressure in the fluid pushing down on its top side, and (3) the pressure in the fluid pushing up on its bottom side.The combination of these three forces is called the buoyancy force.