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Flashcards in Lecture #5 Deck (61):
1

What 2 processes does the suns energy drive?

Hydrologic cycle
All Weather phenomena

2

What % of solar radiation makes it down to earths surface?

45%

3

What are the gases that make up the atmosphere?

N2 78%
O2 21%
Water vapour, CO2, other trace gases= 1%

4

What is the structure of the atmosphere?

Tropo
Strato
Meso
Thermo

5

Which area of the atmosphere is all whether confined too?

Troposphere

6

Which layer of the atmosphere has the O3 layer?

Stratosphere

7

What does the O3 layer do?

Naturally occurring and protect us form harmful UV rays

8

What are the 3 prefixes for naming clouds and what elevation do they refer too?

-Heigh of cloud
High cloud: cirro
Mid level: alto
Low cloud: strato

9

What are the 2 suffixes for naming of clouds and what do they describe?

-Appearance of cloud
Puffy: cumulus
Flat: stratus

10

What does it mean if a cloud name contains "nimb"?

Cloud will produce precipitation

11

What are fronts?

Mark the boundaries between 2 air masses

12

What does the name of fronts describe?

Describes the type of air behind that front

13

What are the 2 types of fronts?

Hot: less dense
Cold: More dense

14

At any moment how many thunderstorms are occurring on Earth?

2000

15

What is required for the development of a thunderstorm?

-Unstable environment
-Water vapour
-Rising air (or a lifting mechanism like a front)

16

What are the 3 stages of thunderstorm development?

1. Cumulus
2. Mature
3. Dissipative

17

What is hail and where is it formed?

Its formed during thunderstorms in tall clouds

18

How is hail formed?

Updrafts in the cloud repeatedly force water droplets up. It develops a ring of ice around it each time it enters the cold part of the cloud

19

Lightening definition

A spark of electricity occurring in a cloud

20

Where does the majority of the lightening strike?

within the cloud
-sometime the atmosphere refracts thunder making it inaudible

21

What is the main requirement for lightening ?

cumulonimbus cloud containing a region of opposite charges

22

Tornado definition

A rotating column of air touching the ground that formed within a supercell thunderstorm

23

What is a funnel cloud?

When a rotating column is NOT touching the ground

24

Characteristics of tornadoes?

- ~300m wide
- Travel SW-->NE ~50km/h
-Exist for less than 30 mins
- Common in spring

25

What are the 3 defined stages of a tornado life cycle?

1. Organizational stage
2. Mature stage
3. Rope Stage

26

What is the organizational stage?

-Wind shear causes rotation to develop
-funnel cloud protrudes from above
-dust and debris rotate beneath

27

What is the mature stage?

Most severe damage occurs at this stage

28

What is the rope stage?

Tornado stretches out and weakens

29

What is wind shear?

a change in wind speed or direction over a distance

30

What scale do we use to classify tornadoes?

Enhanced Fujita Scale
0-5

31

Characteristics of an EF5 tornado?

Complete devestation
Wind 322km/h

32

What is the US and the Canadian tornado Alleys?

US: kansas + Oklahoma
Canada: Southwestern ontario

33

Why do tornado alleys exist?

They occur where hot and cold air masses collide
-also in areas of relatively flat land

34

What and when was the "Super Outbreak" of tornadoes

Occurred April 3rd 1974 where 148 tornadoes touched down between Ontario and Alabama in one day

35

What year did the largest tornado outbreak occur? and how many?

2011
SE USA 358 touched down
-324 people killed

36

Why is it easy to predict the direction of tornadoes?

They generally move in an almost perfect straight line

37

Characteristics of the Goderich Tornado?

-Killed 1 person
-August 2011
-EF3
-Radar showed curved wind formation on RADAR
-Formed over Lake Huron
-Warning issued 12 mins before it reached to town

38

What are tropical cyclones?

high winds, heavy rains and storm surges
-need warm water and form near the equator
-Includes tropical depressions, tropical storms and hurricanes

39

What are extratropical cyclones?

Form at latitudes 30-70degrees
-associated with front
-contain rain snow freezing rain

40

What are the 4 stages of tropical cyclone development ?

1. Tropical disturbance: Large area of low pressure with unsettled weather
2. Tropical Depression: Unorganized area of thunderstorms
3. Tropical Storm: Orangized area of thunderstorms; wind speed 65-119km/h
4. Hurricane: Area of low pressure; wind speed of at least 120km/h

41

How warm does the water need to be in order to form a tropical cyclone?

26 degrees C

42

What are the 3 components of a Hurricane?

1. Eye: region in the center with light winds and clear skies
2. Eyewall: ring of intense thunderstorms that whirl around the eye
3. Spiral Rain Bands: Rings of tall clouds and heavy rain that exists throughout the hurricane

43

What are the 5 letters skipped for male/female naming of thunderstorms?

Q U X Y Z
-naming started in 1953

44

Do hurricanes typically move faster or slower?

Slower
-~20km/h
-speed varies depending on what side of the hurricane you're on

45

What is a storm surge?

When powerful winds create an abnormal rise in sea level
-most devastating effect of hurricanes

46

What scale do we use to classify hurricanes?

Saffir-Simpson Scale
1-5
-based on wind speed

47

When is the official hurricane season?

June 1st-November 30th
-most occur in august-sept

48

What was the main cause of damage from Katrina?

From flooding
-actual city is below sea level, and on the other side is the mississippi

49

What is fog?

It is a cloud with its base at the earths surface and reduces visibility to less than 1 km

50

When does fog occur?

At night when the air cools to dew point and the vapour condenses to droplets
-stays near the ground because its the coolest
-cold dense air sinks

51

What characteristics classify a Blizzard?

- Wind at least 40km/h
-Snow falling or blowing
-Visibility less than 400m
-All must occur for at least 4 hours

52

What is lake effect snow?

Cause by cld air moving over relatively warm water
-heavy snowfall downwind from lakes are the snowballs

53

What is lake effect clouds?

Clouds form over lakes and move down wind

54

What are Haboobs?

Sandstorms that occur in arid and semi arid regions
-Forms from downdrafts on the leading edge of a thunderstorm

55

What are dust devils?

Small spinning vortex of air formed over hot dry land
-caused as hot air rises, the wind direction may change due to obastacles
-results in a spinning column
-no clouds

56

Ice storm definition?

Mainly caused by freezing rain
-rain freezes upon impacting the surface
-weight major issue

57

What is a drought?

Extended period of unusually low precipitation

58

What is wind chill?

It is a correction facto to a temperature reading cause obit the presence of wind making the air feel cooler than the temperature suggests

59

What is Humidex?

It is a correction factor to a temperature reading caused by high levels of humidity making the air feel warmer than the temperature suggests

60

How do we minimize severe weather hazards?

weather satellites detecting cloud cover
-RADAR

61

What are the 3 categories of altering people of weather hazards?

Watch: An alert covering a wide area. Conditions favour the development of hazardous weather but none has been reported
Warning: An alert that usually covers smaller areas. Indicated that hazardous weather is currently occurring in the area
Advisory: used to alter the public of less hazardous weather conditions