exam 2 Flashcards
1
Q
What regions are tornadoes typically generated in?
A
Regions of already severe thunderstorms
Tornadoes are common in areas where air is undisturbed by mountains, particularly in the Midwest USA.
2
Q
What are the two prime factors for tornado initiation?
A
- General topography
- Local climate
3
Q
What is ‘tornado alley’?
A
A region in the USA where tornadoes are very common, including TX, OK, KS, NB, IA, MO, IL
Texas has the most tornadoes, while Alaska has the rarest tornado touchdowns.
4
Q
What are the average dimensions of a tornado?
A
- Width: 75 yards
- Track length: 1-4 miles
- Time on ground: 5 minutes
- Forward speed: 25 mph
5
Q
During which season do ideal conditions for tornado formation typically occur?
A
Spring to early summer
This prime season appears to be shifting earlier.
6
Q
What is the prime time of day for tornado formation?
A
Late afternoon to late evening
This time corresponds to maximum local ground and atmospheric heating.
7
Q
What types of winds contribute to tornado structure?
A
- High level, relatively dry/cooler winds from the west
- Lower level, warm/wet winds from the southeast
8
Q
What is a ‘roller’ in the context of tornado formation?
A
Winds that form cyclonic rotation parallel to the ground
9
Q
What can large thunderstorms do to warmer air?
A
Pull warmer air upward from lower levels, providing energy for the storm
10
Q
What is the significance of a tornado’s touchdown?
A
It marks the point at which a tornado is born
11
Q
What are tornado ‘families’ or ‘swarms’?
A
Multiple tornadoes produced by large storms
Example: A large tornado swarm in 1974 caused damage in 13 states.
12
Q
What was the total damage and casualties from the 1974 tornado swarm?
A
- 148 tornadoes touched down
- 307 killed
- Over 6,000 injured
- $600 million in damage (in 1974$)
13
Q
What is the lowest pressure recorded inside a tornado?
A
As low as 3 inches of mercury (Hg)
14
Q
What is the general track direction of tornadoes?
A
SW to NE
15
Q
Who created the Fujita Scale and when?
A
Professor Theodore Fujita in 1971
16
Q
What does the Enhanced Fujita Scale range from?
A
EF0 to EF5
17
Q
What are the wind speeds and damage classifications for EF0 on the Fujita Scale?
A
- Wind: 65 - 85 mph
- Damage: Minor damage to buildings/trees
18
Q
What are the wind speeds and damage classifications for EF5 on the Fujita Scale?
A
- Wind: > 200 mph
- Damage: Complete destruction
19
Q
What is the purpose of the TOTO device?
A
To measure atmospheric parameters from inside a tornado
20
Q
What challenge did TOTO face during its operation?
A
It was difficult to safely place it in the path of an oncoming tornado
21
Q
What is the Storm Prediction Center (SPC) responsible for?
A
Monitoring regional weather conditions and issuing risk warnings for severe weather
22
Q
What technology does the National Severe Storms Laboratory (NSSL) use?
A
Doppler radar
23
Q
What is a ‘hook echo’?
A
A distinctive pattern in Doppler radar indicating mesocyclones and tornado vortex signatures
24
Q
What is the function of mobile Doppler radar?
A
To image nearby tornadic activity and capture three-dimensional images of a tornado’s structure
25
What are some mitigation strategies for tornadoes?
* Building underground tornado bunkers
* Building 'safe rooms' above ground
* Improving scientific instrumentation and early warning systems
26
True or False: Most injuries and deaths from tornadoes occur from being picked up and thrown great distances.
True
27
Fill in the blank: The Enhanced Fujita Scale was modified in _______.
[2007]
28
29
What are the primary causes of the most damaging and costly disasters on Earth?
Weather hazards
30
What was the largest loss of life from a weather-related disaster?
Cyclone Bhola in Bangladesh in 1970, killing ~500,000 people
31
What are examples of primary/direct weather threats?
* Tornadoes
* Hurricanes
* Ice storms
* Nor'easters
* Lightning
32
What are examples of secondary/indirect weather causes?
* Drought
* Floods
* Forest fires
* Desertification
* Air pollution
33
Which federal agency is most responsible for monitoring weather events?
National Oceanic and Atmospheric Administration (NOAA)
34
What is the website for the National Oceanic and Atmospheric Administration (NOAA)?
http://www.noaa.gov/
35
What is the significance of weather-related hazards in the United States?
* Highest number of tornadoes
* Second highest number of lightning strikes
* Only country with large nor'easters
* High number of landfall hurricanes
36
What were the top two costliest disasters in the US between 1994 and 2022?
* Hurricane Katrina (2005)
* Hurricane Maria (2017)
37
What was the deadliest natural disaster in the US?
The hurricane that hit Galveston, TX in 1900, killing ~6,000 – 12,000 people
38
What can thunderstorms bring?
* Heavy rains
* Flash flooding
* Strong winds
* Hail
* Lightning
* Tornadoes
39
Where are thunderstorms most likely to occur in the United States?
Central and southern states, with Florida having the highest number of thunderstorm days
40
How many thunderstorms occur at any given time on Earth?
~1,800 thunderstorms
41
How many thunderstorms does the US experience each year?
~100,000 thunderstorms
42
What is the average number of tornadoes that develop from thunderstorms in the US each year?
~1,000 tornadoes
43
What is a thunderstorm?
A storm formed from moisture, rapidly rising warm air, and a lifting force
44
What is lightning responsible for?
Thunder
45
What are the characteristics of multi-cell storms?
* Regions of intense updraft
* High rainfall followed by downdrafts
* New cell formation and lines of thunderstorms
46
What are supercell thunderstorms characterized by?
Rotating winds called a mesocyclone
47
What are the key characteristics of supercell thunderstorms?
* Air rises and turns at speeds up to 170 mph
* Cooling causes condensation and energy release
* Overshooting top forms at the top of the column of rising air
48
How does the National Weather Service issue storm warnings?
* Severe thunderstorm watch: Severe thunderstorms are possible
* Severe thunderstorm warning: Severe thunderstorms are occurring
49
What technology is used for monitoring thunderstorms?
* Satellites
* Doppler radar
50
What is lightning?
An electrical discharge from the buildup of positive and negative charges within a thunderstorm
51
How often do lightning strikes occur worldwide?
~6,000 bolts hit the Earth every minute
52
How many people does lightning kill each year worldwide?
~2,000 people
53
What is the typical length and width of a lightning bolt?
3-4 miles long and ~1-inch wide
54
What is the temperature of a lightning bolt?
Hotter than the surface of the sun, approximately 55,000°F
55
What causes the buildup of charges in a thunderstorm?
Separation of ice crystals due to wind currents
56
What is cloud to ground lightning?
The most dangerous type of lightning, but only about 20% of all lightning
57
What are common victims of lightning strikes?
* More men than women
* 25% of victims are struck dead immediately
58
What percentage of annual insurance claims are related to lightning strikes?
~5% (~$1 billion)
59
What percentage of annual power outages are caused by lightning?
~30% (~$1 billion)
60
How many PCs are destroyed annually due to lightning?
> 100,000 PCs (~$100 million)
61
What are the short, medium, and long-term effects of dry weather and heat waves?
Short: heat wave (days to weeks)
Medium: drought (months to years)
Longer: desertification (years to decades)
## Footnote
Heat waves can lead to immediate health crises, while prolonged droughts and desertification have long-lasting environmental impacts.
62
What significant event occurred in Riyadh, Saudi Arabia, on March 10, 2009?
A dust cloud engulfed the city, reducing visibility to 0-3 meters, causing traffic jams and halting airport operations
## Footnote
This event highlights the increasing frequency of dust storms in urban areas.
63
How many lives were claimed during the 2003 heatwave in Europe?
Estimated 35,000 lives
## Footnote
France specifically recorded 14,802 deaths due to extreme temperatures.
64
What was the impact of the heatwave in Italy between July 8 and July 17, 2023?
659 mainly elderly people died due to heat
## Footnote
This was part of a larger trend, with a total of 968 excess deaths recorded.
65
What were the conditions during the Chicago heatwave in July 1995?
Strong upper-level ridge of high pressure, numerous heat records, high humidity
## Footnote
465 people died, predominantly affecting the poor and elderly.
66
What has been the trend in average global temperature over the last 25 years?
Increased by 1°F or 0.6°C
## Footnote
This rate is 5 times more than the previous century.
67
What defines a desert?
A region with a mean annual precipitation < 25 cm (~10 inches) per year
## Footnote
Deserts have very little vegetation and support for life.
68
How much of the Earth's land surface is classified as a desert?
Approximately 1/3
## Footnote
This classification includes various types of deserts.
69
What are the four primary classes of deserts?
* Polar
* Mid-latitude (continental)
* Trade-wind
* Coastal
## Footnote
Each class has unique characteristics based on location and climatic conditions.
70
What is the precipitation range for hyper-arid deserts?
< 2.5 cm of precipitation/year
## Footnote
These areas are characterized by little to no vegetation.
71
What characterizes arid deserts?
Receives 2.5 - 25 cm of precipitation/year, marked by some drought-resistant vegetation
## Footnote
Playas and saline lakes are common in these regions.
72
What is desertification?
Slowly advancing spread of desert conditions due to prolonged drought, climate change, and anthropogenic land degradation
## Footnote
It can lead to severe consequences for human populations and ecosystems.
73
What are the main causes of desertification?
* Climate change
* Land degradation/soil erosion
* Over-cultivation
* Over-grazing
* Deforestation
* Bad irrigation practices
## Footnote
These factors contribute to the transition of land into desert-like conditions.
74
What methods are used for monitoring desertification?
* Weather and soil moisture conditions
* Ground- and satellite-based instruments
* Human land use practices
## Footnote
Effective monitoring is crucial for understanding and mitigating desertification.
75
True or False: Once a long-term drought transitions to desertification, little can be done to mitigate the effects.
True
## Footnote
This emphasizes the importance of proactive measures before conditions worsen.
76
landslide potential maps
- used to identify slide prone areas
- the distribution of past landslides
- identify potentially unstable slopes
77
incidence (landslide)
the percentage of slope failure over a given area
can be high, moderate, or low
78
susceptibility (landslides)
the probable degree to slope failure of rocks and soils due to natural or artificial cutting, loading of slopes, or anomalously high precipitiation
(high, mod, low)
79
La Conchita, CA 2005 - landslide
prior slope failure (landslide) in 1995
o after which, the homes were rebuilt
o excessive rain in January, 2005
o 1995 debris was mobilized, and a new slide/flow created
destroyed 15 homes
killed 12 people
80
Oso, WA (2014) - landslides
landslide transitioning into a mud/debris flow
o engulfed a rural neighborhood
o covering 1 square mile
43 people were killed
49 homes and other structures destroyed
81
slopes
over-steepend slopes are an issue when:
- seismic activity
- rainfall
examples:
- weak base of slope
- orientation of bedding
- evidence of prior slides
82
predicting mass movements
slopes
surface water buildup
vegetation
visible damage to structures
morphologic features resulting from old slides
83
prevention and mitigation
slope drainage
perforated pipe
wells into sloped terrain
slope reduction
engineering structures
retaining walls
rock bolts
cable nets
rock sheds and tunnels
84
types of mass movements
1. fall: material moves through the air
2. slide: material moves but stays in contact with underlying surface
3. flow: materials break up and move as a fluid
85
types of slides
rock slide: most common on steep slopes
land slides: moves rapidly as a unit or series of units
slump: sliding of material along curved surface
86
driving forces of landslides
gravity
excess loading
87
angle of repose and factors
maximum angle at which granular material can be piled
affected by:
particle size
particle shape
sorting
packing
moisture content
88
role of water in landslides
increases loading
reduces cohesion (more unstable)
89
initiation of mass movements
saturation by water
over steepening of slopes
freeze/thaw cycles
earthquakes
volcanic eruption
vibrations (man made)
overpiling
90
types of flows
creep: very slow of soil down a slope
solifluction: slow movement of water/ice saturated sediment in cold environments
mud and debris flows: rapid movement of soil and water
debris avalanche: unconsolidates debris moving slow
91
types of volcanic monitoring
seismic
deformation
heat discharge
gas discharge
water flows
92
seismic monitoring
network of seismometers to measure the magnitude (M), frequency (F)
and distribution (position) of earthquake types under an active volcano
93
seismic activity caused by volcanos
high fequency EQs: magma pushes rock out of the way as it rises, shallow, small M high F
volcanic tremor: magma movement in the conduit and gas bubbles in magma, long period EQs, lower depth
94
deformation (volcano)
measurement of changes in the volcano's shape due to increasing pressure
95
heat flow (volcano predictor)
volcanoes begin to heat up days-months before eruption
soil and ground water temp can be measured
96
volcanic gas monitoring
chemistry of volcanic gas to determine composition of magma and likelihood of eruption
97
types of volcano hazard mitigation
physical structures
public education
use of modern tech
98
physical structures in lava mitigation
laval diversion
water cooling
lahar diversion
99
volatiles
any dissolved gas or liquid composition in magma
100
viscosity
internal resistance to flow (strain) by a substance when subjected to shearing
(stress)
101
basalt composition lava
dark igneous rock characterized
by small (<1 mm) grains
produced by partial melting of
upper mantle material
these lavas form shield-shaped
volcanoes
102
andesite compostion lava
- lava production at subduction
zones
-dominated by fluids from ocean
slab driven into the overlying
mantle of the continental crust
- wet , forms cone-shaped volcanoes
103
rhyolite composition lava
produced at subduction zones
or other large volcanic centers
"sticky" magma, very explosive
104
hawaiian style eruption
mostly flows on the surface
low eruption columns
forms spatter and cinder cones
typically basalt
105
strombolian style eruption
low ask columns
more energetic than hawaiian
basalt or andesite
106
pelean stype eruption
collapse of a lava dome
large ash columns are rare
pyroclastic flows
107
surtsean style
violent explosions as magma contacts seawater or groundwater
highly fragmented ash
108
plinian style eruption
high ash columns
powerful, sustained
large pyroclastic flows
