AVIA101 Lecture Notes - Lecture 22: Arctic Front, Intensify, Polar Front
Document Summary
Can never take a technical log on board on the aircraft. Stability in the air vertical movements of air parcels: determined by temperature difference b/w rising air parcel and surrounding air. Stable (returns to original position), unstable(when disturbed it continues to move in direction of disturbance), neutral stability (remains fixed after disturbance changes its position) Convection: air heated at the surface rises (unstable) Orographic: air moving over an upslope, mountain range (forced up) Convergence: air moving into a low pressure area, air rises up as it moves into the area. Frontal: warm air mass forced aloft by cold air mass. Mechanical: surface friction, obstructions (town, foot hills), turbulence. Amount of temperature lost over an altitude is lapse rate. Steep lapse rate: temperature decreases rapidly with altitude (unstable air) Shallow: temperature decreases very slowly with altitude (stable air) Isothermal: temperature does not change with an increase in altitude: more stable than shallow lapse rate.
