GEOGRAPHY Notes for class

GEOGRAPHY Notes for class - GEOGRAPHY November 20, 2007...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
GEOGRAPHY November 20, 2007 Cold and dry polar continental Warm and moist (formed over ocean) When airmasses meet at fronts- COLD OR WARM(if being directed by a dominant warm air mass) weather conditions are created typically… At the front air rises and cools then drops it contents- the cross section shows how air masses behave- as it rises it is cooled and reaches dew oint- a cold front is much steeper and more violent weather conditions- this depends on the dew- RAIN, SNOW, OR ICE- if dew point is above freezing then rain- This weather phenomenon has certain important features which occur throughout the year- SOME ARE VERY IMPORTANT TO UNDERSTAND- THREE!!! 1. Thunderstorms- rumbling occurs with three conditions- within warm, moist air mass. 2. Along linear fronts- particularly cold fronts 3. Along slopes when there is orographic uplift of air. 2. Tornados- most violent cyclonic storms in weather systems- they are associated with thunderstorms or with hurricanes and occur in all states of the u.s. and Canada- however, there is a particular corridor from texas to n.e Kansas where they are most frequent (tornado alley)- funnel shaped cloud with a route downward- degree of strength is measured by fujita scale- rotational speed at fo- the speed is 40-74 miles per hour 261-381 mph at highest. 3. Hurricane-very destructive possibly- formed fundamentally in the tropical areas- certain fundamental conditions are required formed on western side of ocean where temp of ocean is 80 degrees and above, and 10 degrees north and south of the equator- tropical cyclones, hurricanes- atlantic, typhoons in pacific. 1. First low pressure or area of depression (surrounded by a high pressure system) the core location begins to generate winds and air movement- the winds first seek to move from high to low pressure areas but are also diverted by coriolis effect (in the north movemts are to the right and in the south movements are to the left. The pressure gradient the movements are inwards but are deflected right.this results in a wind
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
movement that is counter-clockwise. As the winds circulate, they rise and the condition for disturbance rises. And when the speed reaches 39 mph it is called a tropical storm- because this system is on warm water it gathers energy and its momentum increases causing it to go faster- when it reaches 74mph it is called a category one hurricane. Imagine two forms- it is circulating but also directionally moving north westwards and continues to gather momentum until it reaches land area. Can move up to category 5 when the windspeed is over 155mph. because of the frequency and the north atlantic- it is from june 1 to nov. 30. They are given names. KATRINA- wreaked enormous havoc- developed into category 4 to 140
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 19

GEOGRAPHY Notes for class - GEOGRAPHY November 20, 2007...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online