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Flashcards in Lecture #5 Deck (61)
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1
Q

What 2 processes does the suns energy drive?

A

Hydrologic cycle

All Weather phenomena

2
Q

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

A

45%

3
Q

What are the gases that make up the atmosphere?

A

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

4
Q

What is the structure of the atmosphere?

A

Tropo
Strato
Meso
Thermo

5
Q

Which area of the atmosphere is all whether confined too?

A

Troposphere

6
Q

Which layer of the atmosphere has the O3 layer?

A

Stratosphere

7
Q

What does the O3 layer do?

A

Naturally occurring and protect us form harmful UV rays

8
Q

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

A

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

9
Q

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

A

-Appearance of cloud
Puffy: cumulus
Flat: stratus

10
Q

What does it mean if a cloud name contains “nimb”?

A

Cloud will produce precipitation

11
Q

What are fronts?

A

Mark the boundaries between 2 air masses

12
Q

What does the name of fronts describe?

A

Describes the type of air behind that front

13
Q

What are the 2 types of fronts?

A

Hot: less dense
Cold: More dense

14
Q

At any moment how many thunderstorms are occurring on Earth?

A

2000

15
Q

What is required for the development of a thunderstorm?

A
  • Unstable environment
  • Water vapour
  • Rising air (or a lifting mechanism like a front)
16
Q

What are the 3 stages of thunderstorm development?

A
  1. Cumulus
  2. Mature
  3. Dissipative
17
Q

What is hail and where is it formed?

A

Its formed during thunderstorms in tall clouds

18
Q

How is hail formed?

A

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
Q

Lightening definition

A

A spark of electricity occurring in a cloud

20
Q

Where does the majority of the lightening strike?

A

within the cloud

-sometime the atmosphere refracts thunder making it inaudible

21
Q

What is the main requirement for lightening ?

A

cumulonimbus cloud containing a region of opposite charges

22
Q

Tornado definition

A

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

23
Q

What is a funnel cloud?

A

When a rotating column is NOT touching the ground

24
Q

Characteristics of tornadoes?

A
  • ~300m wide
  • Travel SW–>NE ~50km/h
  • Exist for less than 30 mins
  • Common in spring
25
Q

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

A
  1. Organizational stage
  2. Mature stage
  3. Rope Stage
26
Q

What is the organizational stage?

A
  • Wind shear causes rotation to develop
  • funnel cloud protrudes from above
  • dust and debris rotate beneath
27
Q

What is the mature stage?

A

Most severe damage occurs at this stage

28
Q

What is the rope stage?

A

Tornado stretches out and weakens

29
Q

What is wind shear?

A

a change in wind speed or direction over a distance

30
Q

What scale do we use to classify tornadoes?

A

Enhanced Fujita Scale

0-5

31
Q

Characteristics of an EF5 tornado?

A

Complete devestation

Wind 322km/h

32
Q

What is the US and the Canadian tornado Alleys?

A

US: kansas + Oklahoma
Canada: Southwestern ontario

33
Q

Why do tornado alleys exist?

A

They occur where hot and cold air masses collide

-also in areas of relatively flat land

34
Q

What and when was the “Super Outbreak” of tornadoes

A

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

35
Q

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

A

2011
SE USA 358 touched down
-324 people killed

36
Q

Why is it easy to predict the direction of tornadoes?

A

They generally move in an almost perfect straight line

37
Q

Characteristics of the Goderich Tornado?

A
  • 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
Q

What are tropical cyclones?

A

high winds, heavy rains and storm surges

  • need warm water and form near the equator
  • Includes tropical depressions, tropical storms and hurricanes
39
Q

What are extratropical cyclones?

A

Form at latitudes 30-70degrees

  • associated with front
  • contain rain snow freezing rain
40
Q

What are the 4 stages of tropical cyclone development ?

A
  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
Q

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

A

26 degrees C

42
Q

What are the 3 components of a Hurricane?

A
  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
Q

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

A

Q U X Y Z

-naming started in 1953

44
Q

Do hurricanes typically move faster or slower?

A

Slower

  • ~20km/h
  • speed varies depending on what side of the hurricane you’re on
45
Q

What is a storm surge?

A

When powerful winds create an abnormal rise in sea level

-most devastating effect of hurricanes

46
Q

What scale do we use to classify hurricanes?

A

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

47
Q

When is the official hurricane season?

A

June 1st-November 30th

-most occur in august-sept

48
Q

What was the main cause of damage from Katrina?

A

From flooding

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

49
Q

What is fog?

A

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

50
Q

When does fog occur?

A

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
Q

What characteristics classify a Blizzard?

A
  • Wind at least 40km/h
  • Snow falling or blowing
  • Visibility less than 400m
  • All must occur for at least 4 hours
52
Q

What is lake effect snow?

A

Cause by cld air moving over relatively warm water

-heavy snowfall downwind from lakes are the snowballs

53
Q

What is lake effect clouds?

A

Clouds form over lakes and move down wind

54
Q

What are Haboobs?

A

Sandstorms that occur in arid and semi arid regions

-Forms from downdrafts on the leading edge of a thunderstorm

55
Q

What are dust devils?

A

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
Q

Ice storm definition?

A

Mainly caused by freezing rain

  • rain freezes upon impacting the surface
  • weight major issue
57
Q

What is a drought?

A

Extended period of unusually low precipitation

58
Q

What is wind chill?

A

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
Q

What is Humidex?

A

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
Q

How do we minimize severe weather hazards?

A

weather satellites detecting cloud cover

-RADAR

61
Q

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

A

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