GEO 211 1st Edition Lecture 29 Outline of Last Lecture I. El Nino and La NinaA. El nino- abnormal warming of the Pacific Ocean between South America and Australia and Indonesia in the equatorial regionB. La nina- extensive, below normal cooling of the central/eastern Pacific OceanII. Air masses and frontsA. Air mass- large body of air that has a uniform weather characteristics, particularly temperature and water vapor contentB. Source regions (birthplace): flat land surfaces with light windsOutline of Current Lecture III. Air masses that affect North AmericaA. Continental Arctic (CA)B. Maritime Polar (mP)C. Continental Polar (cP)D. Continental tropical (cT)E. Maritime tropical (mT)F. Fronts- Warm front- OverrunningG. Cold frontH. Occluded front- Two types:o Cold typeo Warm typeI. Stationary frontCurrent LectureIII. Air masses that affect North AmericaThese 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.A. Continental Arctic (CA)- Very cold, dry- Origin: arctic basin and the GreenlandB. Maritime Polar (mP)- Mild (cool), moist- Origin: North Pacific, North AtlanticC. Continental Polar (cP)- Cold, dry- Origin: interior Canada, parts of Alaska D. Continental tropical (cT)- Hot, dry- Origin: Northern Mexico, Southwestern US (summer only)E. Maritime tropical (mT)- Warm, moist- Origin: Gulf of Mexico, Caribbean sea, tropical AtlanticF. Fronts- Transition zone between two different air masses- Warm front: zone where warmer air is replacing cooler airo Ex: mT replacing CP by cooler air retreats while warm air glides gen Hy over retreating cooler air- a gentle slope for ms average slope (1:300)- Overrunning- gliding over cooler airo Different clouds develop along the warm front slope (figure 11.22)o Warm front moves slowlyG. Cold front- Zone where cooler air is replacing warmer air - Cold, dense air lifts warm air up steeply forming a steeper cold front slope- Rain cloud formed is cumulonimbus- Accompanied with heavy rain fall and floods, thunderstorms, hail, tornadoes, lightning- Cold front moves faster than warm frontH. Occluded front- Formed when a cold front catches up with a warm front- Two types:o Cold type- air mass behind the cold type occluded front is colder than air ahead of ito Warm type- air mass ahead of the occluded front is colder than air behinditI. Stationary front- A front that is nearly stationary- Winds blow almost parallel an from opposite directions on each side of the
View Full Document