GEOG 111 1st Edition Lecture 30 Outline of Last Lecture I. Types of weather around wave cyclonesII. Cyclone tracksa. The Alberta Clipperb. Texas-Great Lakesc. The Gulf-Atlantic CoastIII. Frozen precipitationa. Typesb. Weather setupOutline of Current Lecture I. Processes associated with freezing rain developmentII. Factors that control ice buildupIII. Weather features that produce big ice stormsCurrent LectureI. Processes associated with freezing rain developmenta. Higher altitudesi. Snow- Bergeron processb. Warm nosei. Warm advection warming1. Warmer air coming from south/south west carrying air north (produces warm nose) a. Frontal liftingb. Warmer air forced over colder airii. Melting of snow cooling1. Sensible heat converted to latent heatiii. Frontal lifting cooling1. As air rises, it coolsc. Cold wedgei. Freezing of rain warming (freezing rain is a self-limiting process)1. Sensible heat is liberated by freezing raina. Need constant supply of cold dry air for an ice stormii. Dry air evaporation of rain (because air is not saturated) coolingiii. Cold air advection cooling1. Bottom of columnII. Factors that control ice buildupa. Antecedent temperature of surfaceThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.i. Example: ice accumulation on south vs. north facing slopes, asphalt (low albedo)vs. concrete surface (cooler, more light reflecting, more likely to buildup), groundvs. tree limb (doesn’t take long for them to cool off, exposed to wind)b. Wind speedi. Materials will go down to freezing more quicklyc. Rainfall rate/durationi. In a given ice storm, freezing rain isn’t falling too quicklyii. Ideal: lower rate of precipitation over a longer durationIII. Weather features that produce big ice stormsa. Strong anticyclone to the north that provides a replenishing supply of cold, dry air.b. Slow-moving, wave cyclone that moves south of the area and provides persistent warm and moist air advection over the wedge of cold
View Full Document