Geo test 1 slideshow questions

what is disaster risk and what is it function of

potential loss of life, injury, assets which could occur in specified period of time

how does fire cloud promote spread of wildfire

produce tornado force winds that transport embers producing lightening that can spark addtl. blazes far away from original fires

what is ike dike who build it

proposed coastal barrier protecting houston/ galveston from hurricane storm surge army corp of engineers 23-31 bil

20. What is the connection between rain, soil moisture, and flooding?

rainfall rate < infiltration capacity flow 10mph goes down 15mph goes subsurface flow toward river

9. What does a flood recurrence interval and/or flood probability tell you about a river?

recurrence interval tells you likelihood of magnitude of flood each year

What happens to a soil's internal friction as pore-water pressures increase?

reduce magnitude

what did homeowner insurance affordability act of 2014 do

reinstated subsidized rates, delayed higher full risk premiums placed caps on other increases

. What is porosity and what controls the magnitude of porosity for loose sediment?

relative volume of void or empty space btwn solid particles grain size distribution controls magnitude of porosity

Debris flows, slumps, and slides are all derived from what kind of deposits and/or bedrock?

remobilized

18. What is a 'Flood Pool'?

reservoir's footprint

What is the resisting strength of water and air?

resist < water/air no flow resist> water/air flow

zone of low atmospheric pressure assc. w/ rising or sinking air

rising moist air

how is exposure to wildfire changing in CA

risk increasing because more people moving into mountainous areas making it difficult to clear out fuel

28. What is the role of a dam spillway?

section of dam designed to pass water from upstream to downstream

12. What areas are systematically missed by this present flood mapping?

areas around small streams and across broad swaths of the midwestern and northwestern United States

18. What is the role of infiltrated rain water on a flood hydrograph?

correlated with falling limb

In the northern hemisphere what is the rotation direction associated with air flow toward a low-pressure zone and its convection?

counter clockwise

in mtn areas wildfire increase likelihood of what other disaster

debris flows

Everything else being equal, what happens to infiltration rate as grain sorting decreases (i.e., the range of particle sizes increases)?

decrease

why does tilting of supercell thunderstorm allow it to keep growing

deep and persistent rotating updraft called a mesocyclone. shear maintaining a separate updraft and downdraft region.t reduces the likelihood that too much rain-cooled, stable air from the downdraft region will be ingested into the updraft, causing the storm to weaken.

what is diff btwn debris flow, slump, slide

degree to which material deforms internally small- slide significant-flow slump btwn the two

5. How is the cross-sectional area for a channel connected to the channel discharge?

directly proportional

16. How are river discharge and water-surface elevation correlated?

discharge and elevation go down slowly as infiltrated rain flows underground and feed river

15. Why is the Rising Limb of a flood hydrograph almost always steeper than its Falling Limb?

discharge decreases slowly bc infiltrated rain flows underground

What is infiltration?

downward entry of water into soil

what is infiltration

downward entry of water into soil

What are the 3 primary controls on channel discharge?

drainage basin area, surface slope, precipitation.

23. Why was the 2015 Memorial Day flood on Shoal Creek shorter in duration than the flood on the Blanco River, which in turn was shorter in duration than the flood on the Trinity River?

drainage basin size small correlation btwn channel discharge and water surface elevation

what is a hazards return period or recurrence interval

elapsed time btwn same sized events

. What happens to most soils as they begin to deform?

excess pore water liquefied soil high pressure low strength

16. What is the inundation easement associated with a reservoir?

extra area you can flood

What happens to buildings sitting on top of liquefied soil or sediment?

fall over

what is fire swirl

fire generated wind

what happens when rain falls on a soil that is fully saturated with all pores already full of water?

flooding surface runoff

What two properties of a mass movement determines its destructive impact pressure or kinetic energy?

force area

supercell thunderstorms associated with what style of air lifting

frontal

What are the 3 required components of a wildfire?

fuel, oxygen, heat

What happens when pore-water drains out of a debris flow?

gains speed?

10. The topography of TX is connected to what other property of our state?

geology

What two properties of a soil or sediment deposit control its infiltration rate?

grain size and sorting

12. What is a Hydrograph?

graph showing the rate of flow (discharge) at a specific point on a river versus time. The rate of flow is typically expressed in cubic meters or cubic feet per second (cms or cfs)

what are typical fuels for wildfire

grasses shrub tree slash building

What is the role of gravity in mass movements?

gravity acts on mass applying force that pulls downslope

disaster risk is estimated as function of

hazard, exposure, vulnerability

What is the measured relative loss of sediment from behind burned vegetation dams versus unburned vegetation dams?

high loss on burned dams v. unbured

what is wind and how is it driven

horizontal flow of atmosphere (a gas) is driven by a pressure gradient

29. What happened to the Canyon Lake spillway in 2002?

huge amt of water overfill spillway and cut off canyon lake gorge

natural hazard is different then

human induced hazard

Did a 2017 investigation of Texas high-hazard and significant-hazard dams find more or less these structures in adequate or inadequate condition?

inadequate

Pore water tends to do what to the resisting strength of slope-forming materials?

increase in pore water reduce resisting strenght

In mountainous areas, wildfires increase the likelihood of occurrence for what other natural hazard?

increase likelihood of debris flow

what is hazard vulnerability

increased susceptibility to impacts of a hazard caused by physical, social, or economic factors

Everything else being equal, what happens to infiltration rate as grain size increases?

infiltration rate increase

emphasizing wildfire suppression has done what to fuel loads in forests

inhibiting preventative fuel removal causing fuel loads to increase

what is fire cloud

intense wildfires produce own thunderstorms hot air rises and cools produce lightening

13. What exits between the timing of peak rainfall and the Flood Peak?

lag time

what is base floodplain

land area covered by floodwaters of base flood floodway + flood fringe

6. Is the Magnitude = 1 flood the largest or smallest event on record?

largest

What does the concentric layering often seen in hailstones represent?

layering records rates of accumulation and freezing

30. What needs to happen when the reservoir behind a dam fills up with sediment?

leads to erosion need to let out wter?

Between 2002 and 2017 about 90% of all costs associated with natural disasters in the U.S. occurred in areas having what percentage of the national population?

less than 20%

what is the natural way of removing fuel from forests

letting fires burn

what is most common natural starter of wildfires

lightening

What happens to pore-water pressures during consolidation of a soil

liquefaction

each hazard is characterized by

location, magnitude, return period

Why is the primary cause of increased sediment yields following wildfire?

loss of vegetation

what is downburst

area of strong downward moving air air force outward in all directions producing strong wind

27. What government agency is required to notify homeowners that they are living within a dam's inundation zone?

none

what is slash

organic detritus lying on the ground

6. Are most Inundation Zones of dams inside or outside the mapped 100-year or base floodplain?

outside of mapped flood plain

what is hazard exposure

people and infrastructure located in hazard prone area

how undervalued were homeowner insurance premiums in 2017 when it comes to covering wildfire costs in CA

$24 billion

What is a 'vegetation dam'?

plants that hold sediment

how is straight line flow path from high to low atmospheric pressure modified

air flows from high to low pressure pressure gradient force

what properties are used to estimate vertical velocities assc. w/ convection

-hot air -cold air -viscosity of air - area covered by air w/ diff density -acceleration by gravity

11. What percentage of the conterminous 48 states is presently covered by FEMA flood maps?

60%

what is convectional lifting

air heated near the ground rises vertically due to buoyancy (air near the ground is less dense than cold air directly above )

what is NFIP

(NFIP) is the main program intended to provide federal assistance to homeowners and renters recovering from flood losses. The maximum coverage for one to four family homes is $100,000 for contents and $250,000 for buildings coverage.

what are the 3 properties used to estimate lift force of a tornado or any natural hazard

-air density -wind velocity - roof top area

4. What is the definitions for a Base Flood and how is it used by the National Flood Insurance Program?

1% annual chance flood (informally referred to as the 100-year flood). the national standard used by the NFIP for the purposes of requiring the purchase of flood insurance and regulating new development

what 3 conditions used to define a severe thunderstorm

1) winds exceed 93 km/hr (58 mph); 2) hail is 25 mm in diameter or larger; 3) a tornado is reported.

heat from wildfire flows outward by what 4 processes

1. Diffusion of embers from zone of higher concentration to zones of lower concentration; 2. Radiation from flames and other hot surfaces; 3. Convection of hot gases that rise upwards; and 4. Wind.

What two entities drive Earth's atmospheric circulation?

1. Energy from the Sun (solar radiation) 2. Rotation of Earth

what are 4 stages of a thunderstorm

1. Warms air rises high enough to pass through the lifting condensation level. 2. Condensation of water vapor begins. 3. Condensation of water droplets releases heat (called Latent Heat of Condensation) helping the cloud to rise even higher. 4. Evaporation of falling rain droplets acts to cool air near the ground, shutting down the storms

13. How many people are mapped as being exposed to the 100-year flood using the 'bottom-up' approach?

13 million people

How much money does NFIP currently owe US treasury

20.5 billion

What decision was made in August, 2017, to ensure waters in Lake Conroe did not rise above the inundation easement and what was the consequence of this decision of communities downstream along the San Jacinto River?

207 ft above sea level max. flood communities downstream

What was the federal coverage of major natural disasters in the 1920s, 1950s, 1970s, and 1990s?

20s: 3.3% 50s 6.2% 60s 12.8% 70s: 48% 90s 53%

32. How many sites that handle toxic chemicals are located in flood-prone areas across the country?

2500

why did PG&E file for bankruptcy in 2019

30 billion in liabilities for role in wildfires in 2017/18

. How much of the energy from the Sun is lost back into space versus absorbed into Earth's climate system?

30%

how many of the 40 most expensive disasters btwn 1970-2017 were natural disasters

39

what fraction of dams in TX have been exempted from safety requirements by the Texas Legislature?

44%

btwn 1992-2012 what % of all wildfires in 48 states were stated by people

84%

What is the 'Head Scarp' of a landslide?

: The upper parts of the landslide along the contact between the displaced material and the main scarp.

how and why did CA insurance commissioner place moratorium on cancelation of residential insurance

A 2018 state law allows the California Department of Insurance to require insurers to renew residential policies for one year in ZIP Codes that have been declared wildfire disasters. The CA Insurance Commissioner invoked this law in December, 2019, in an effort to halt an insurance- availability crisis.

What is orographic lifting?

Air flows up a steep land surface, expanding and cooling

what is frontal lifting

Air masses collide at frontal boundaries; less dense air mass rises to form clouds, including lines of severe thunderstorms

how bad did air quality get in sydney in 2019 fires

Australia's clear air standard for Ultrafine Particles = 8 g/m3. Smoking a single cigarette produces 20 g/m3. Recent air-quality readings in Sydney have been as high as 734 g/m3 - the equivalent of about 37 cigarettes.

what is largest wildfire in TX history and what 2 conditions led to it

Bastrop county fire sept 4-oct 10 2011 strong winds from tropical storm lee knock trees onto electrical lines (drought)

how do co2 h2o and released heat fit into fire reaction

C6H12O6=glucose which approximates the composition of cellulose, the main component of wood Plant material is heated up above its point of combustion, and oxygen (O) begins to combine with organic material. Carbon (C) and hydrogen (H) bonds are broken and stored energy is given off as heat. Moisture must be driven off before combustion can begin, so wood with a high moisture content is hard to ignite.

what was world's costliest natural disaster in 2018

Campfire, CA

How much of NFIP's debt did Congress cancel/forgive in 2017?

Congress cancelled $16 B of NFIP debt, making it possible to pay claims for hurricanes Harvey, Irma, and Maria.

. In what cases can Dams mitigate flooding and in what cases may Dams lead to increased exposure and vulnerability to natural disasters?

Dams can mitigate flooding by providing retaining volume for flood waters BUT, improperly managed & maintained dams can lead to both increased exposure and vulnerability to a natural disas

In the northern hemisphere what is the rotation direction associated with air flow away from a high-pressure zone and its descending air?

clockwise

What controls the degree of atmospheric instability that leads to thunderstorms?

Degree of atmospheric instability increases as the temperature differences increase between the warm bottom air and overlying cool air.

what agency is responsible for mapping area flooded by base flood

FEMA

What is FEMA and in what department of the federal government is it located?

Federal Emergency Management Agency within the Department of Homeland Security administers the NFIP (National Flood Insurance Program)

what is FEMA

Federal emergency management agency created in 1970 new administrator of NFIP absorbed into Dept. Homeland security 2003

11. "Flash Flood Alley" of central TX is connected to extreme rainfall produced by what 2 lifting mechanisms?

Frontal Lifting: warm, moist Gulf-coast air rises over denser central TX air mass. Orographic Lifting: steeper land-surface slopes and elevation gain of Balcones Fault Zone (~800 ft =245 m).

What is the name of the wind damage scale? Is the highest rank on the scale associated with winds exceeding 100, 200, or 300 mph?

Fujita wind damage scale Exceeding 200

8. How is Flooding Probability related to flood recurrence interval?

P (flooding probability)=1/R EXAMPLE: If Recurrence Interval = 100 years, there is one chance in 100 that a flood of that magnitude will occur each year. There is a 1/100 (= 0.01 or 1.0 %) probability of flooding of that magnitude in any one year.

what is consistent diff in fuel moisture of wildfires started by humans v. lightening

Human-started wildfires disproportionally occurred where fuel moisture was higher than lightning- started fires.

9. What are the requirements for building on the Flood Fringe?

Most communities permit development in the Flood Fringe if the development is elevated or otherwise protected to the Base Flood Elevation

31. What is TX Senate Bill 339?

Requires homeowners to disclose if their properties are located in: (1) the 500 year floodplain; (2) a flood pool (3) in or near a reservoir; and (4) whether the home has flooded before.

What government agency is required to notify homeowners that they are living within a reservoir's flood pool?

None? tx law doesn't require it Army corp and fed dont require

what is base flow

Normal discharge of the river

what is firefighting trap

Response to periods of worsening fire severity has been to increase fire suppression. Emphasizing suppression can degrade the long-term effectiveness of forest-fire management by:

what is point of combustion

Plant material is heated up above its point of combustion, and oxygen (O) begins to combine with organic material. how easily it will burn

Who decides if the Disaster Relief Fund will cover costs associated with a natural disaster?

President

. What are the units for Channel Discharge and how is it measured?

Q = V× A Q = channel discharge (m3/s) V = average velocity (m/s) A = cross-sectional area of flow (m2) Measured in (m3/s)

7. How is Flood Recurrence Interval calculated?

R= N+1/M r= recurrence interval m= magnitude n= # year of data

what did Biggert waters flood insurance reform act 2012 set out to do

Reform the national flood insurance plan extends it for 5 years trying to protect the housing market and keep property values

How is 'Lifting of Air' connected to significant precipitation events?

Significant precipitation events are driven by the lifting of air that leads to it cooling and the condensation of water vapor into rain drops and/or ice crystals.

What is the trend in number and total cost of billion dollar natural disasters in the U.S. from 1980 2019?

Since 1980, Texas has experienced the highest number of events (104) and is one of the few states that have been impacted by all seven types of the billion-dollar disasters analyzed.

21. What does NASA's SMAP satellite measure?

Soil Moisture Active Passive mission. Provides high-resolution and frequent- revisit global mapping of soil moisture and landscape freeze/thaw state uses two microwave sensors, a radar and a radiometer

what 4 months of the year are associated w/ largest number of tornadoes and supercell storms

april, may, june, july

how are soil density, soil depth, gravity, and the slope of a hillside combined to estimate the downslope driving stress?

T=Fs=Psoil (density) x h (thic) x gravity sinslope

what state has the most dams

TX

what 2 states have greatest concentration of tornadoes per year

TX & OK

Why is Texas 'extraordinary' when it comes to billion dollar natural disasters from 1980 2018?

Texas leads the U.S. in total cumulative costs (~$250 billion) from billion-dollar disasters between 1980-2018.

How is the deflection of a flow path by the Coriolis Effect different in the northern hemisphere versus the southern hemisphere?

The Coriolis Effect deflects moving fluid in the atmosphere and ocean to the right in the northern hemisphere and to the left in the southern hemisphere.

What is the federal sharing of reconstruction costs mandated by the Stafford Act?

The Robert T. Stafford Emergency Relief and Disaster Assistance Act of 1988 authorizes the U.S. President to issue declarations triggering financial and physical assistance through FEMA with 75% federal sharing of reconstruction costs.

What happens to number and size of natural disasters as human populations and infrastructure grow?

The number & size of natural disasters is increasing with growth of human population & growth of infrastructure (buildings, roads, pipelines, etc.).

why did FAIR plan assc. sue CA insurance commissioner in 2019

The organization says the orders will wreck the FAIR Plan's already strained finances. The plan's rates "are currently inadequate and must be increased," but the is state unwilling to grant the industry the rate hikes it needs in high-risk fire zones. FAIR Plan Association President Anneliese Jivan said the orders will destabilize the insurance market because there will be no incentive for private companies to sell plans in wildfire prone areas.

what is convection

The transfer of heat by atmospheric flow warm air rises taking heat up

What are the differences between the 'bottom-up' versus 'top-down' approaches to floodplain mapping?

Traditional "bottom-up" approach: FEMA develops separate hydraulic models for individual river reaches and then stitches model outputs together to generate a nationwide view of area mapped as base floodplain gold standard in flood inundation modeling, but it requires significant resources and time to accomplish. As a result, FEMA mapping currently covers only about 60% of the conterminous United States (CONUS), and the maps may not represent headwater areas and smaller floodplains "Top-down" approach: Automatically create flood inundation models of whole countries using digital elevation models (DEMs), river hydrography Complete estimate to what the flood base plan actually is Gets more detail of streams

What produces lightning in a thunderstorm and how does this differ from what produces lightning in a fire cloud?

Water droplets in the bottom part of the cloud are caught in the updrafts. Downdrafts in the cloud push ice and hail down from the top of the cloud. Where the ice going down meets the water coming up, electrons are stripped off Electrical fields increase until the strength of the charge overpowers the insulating properties of the atmosphere and lightning happens.

25. What is the Inundation Zone associated with a dam?

area downstream of dam covered by water released during dam failure

Why is moist air less dense than dry air at any given temperature?

When water vapor content increases, the density of the moist air decreases relative to dry air at the same temperature. REASON: Water vapor is light compared to N 2 (diatomic Nitrogen) and O 2 (diatomic Oxygen), the dominant components of air (99% by volume). When water vapor increases in air, the amount of N 2 O 2 decreases per unit volume and the density of the mixture decreases compared to dry air.

Can soil infiltration rates exceed 1 inch (2.54 cm) per hour?

no?

What is the definition of natural disaster

a naturally occurring phenomenon that has the potential to cause loss of life, injury, property damage, societal and economic disruption

What is hazard 'mitigation'?

actions to eliminate or reduce threat of natural disaster

how does global warming change vulnerability to fires

acute drought and increasing temperature kills trees and low point of combustion increases exposure

how is a wind path modified by coriolis effect

additional shear and rotation deflects wind

2. What are the aims of the National Flood Insurance Program?

aims to reduce the impact of flooding on private and public structures. Provides affordable insurance to property owners, renters and businesses, encouraging communities to adopt and enforce floodplain management regulations.

what primarily controls density of air and by how much does it vary in atmosphere

air density controlled by temperature molecules per unit volume varies in atmosphere by .1

why do zones of high and low pressure develop in earth's atmosphere

ascending and descending air

The volume of debris flows produced following wildfire has been found to depend on what 3 things?

basin gradient area burned storm rainfall

Why do relatively small changes in flow speed translate into relatively larger changes in impact pressure and destructiveness?

because it is an inverse relationship

What are at least two ways of mitigating debris-flow hazard?

catching flows draining water out of flows

What are the key differences between dams classified as having low-hazard, significant- hazard, and high-hazard potential by the Texas Administrative Code?

low hazard- no loss of human life minimal $ loss significant- 1-6 life 2 structures, economic loss rural area high- 7+ lives 3+ structures excessive economic loss near urban area

Why are debris flows with high pore-water pressures so mobile?

low strength

what is the typical correlation btwn return period of natural hazard and magnitude or size

magnitude and return period correlated- (larger mag= longer return period)

What happens to the mass of a rock or soil when water replaces air-filled pore space?

mass increased

What human activity destabilized Rattlesnake Ridge in Washington State?

mining

What is a Mass Movement = Mass Flow = Sediment-driven Flow?

mixtures of solids and fluid in which solids are distributed throughout flow and play critical role in motion

what produces rotation that leads to tornado formation

multiple air masses moving in different directions

how does a natural disaster differ from natural hazard

natural disaster is serious disruption of society due to hazardous event strictly speaking, disasters, not hazards cause death and damage

Why are logged hillsides more susceptible to debris generation than forested hillsides?

no consolidation of grains so becomes unstable

How do significant rain events trigger debris flows?

no plants/ trees to hold sediment increase vulnerability

is oxygen a limiting component for wildlife development

no, heat and fuel typically limiting

Why is earthquake shaking so effective at producing very high pore-water pressures in soils and sediments?

shear strain to buildup pore fluid pressure creates liquefaction

is a zone of high pressure assc. w/ rising or sinking air

sinking dry air

What did the 2014 Oso landslide do to the Stillaguamish River? Can one natural hazard produce another?

slide dammed river making upstream flooding and catastrophic dam failure

Where is the highest concentration of large clasts (i.e., grains) found in a debris flow?

slow moving front where friction is greatest

what are embers

small pieces of burning or glowing coal/ wood

what is a powder avalance

snow avalanches and dust storms, solids suspended by turbulent fluid (air)

What happens when a soil of grain framework consolidates?

soil has less space for pore water leads to elevated pressures

what is CA FAIR plan

state-mandated program providing access to insurance for individuals who are having trouble insuring their property due to high risk. not a state agency and is not funded by taxpayers. It is funded by an association of private insurance companies, who are required to participate in the plan if they want to do business in California. can cost two or three times as much as traditional insurance and only offers fire insurance. Homeowners must purchase a second plan in the private market to cover other risks and theft, adding to their cost burden.

What is the connection between steepness of topography and landslide occurrence and why?

steeper slope more likely to have landslide

What three conditions are required in of a thunderstorm to produce large hailstones?

strong updraft freezing level relatively close to the ground high wind shear that separates zones of updraft and downdraft provide complicated path through Tstorm to make ice pellets

can infrastructure be built in floodway

strongly discourages or prohibited

How does surface slope and river-valley shape change from the headwaters of a drainage basin moving down slope to its outlet?

surface slope increases speed of headwater?

what is flood fringe

the portion of the floodplain outside the floodway that is usually covered with water from the 100-year flood or storm event. Can flood if needed but isn't super likely to

what is the definition of floodway

the stream channel and that portion of the adjacent floodplain that must remain open to effectively convey floodwaters

Remobilization of slope materials occurs when?

time resisting strength of slope forming materials is exceeded by down slope direct shear stress

What is the best way to predict if a slow-moving landslide is going to transition into a fast-moving landslide?

timing of slip rates

What is 'liquefaction'?

transformation of water saturated sediments from solid to liquid as consequence of increase pore pressure

What is the connection between air temperature and the amount of water vapor that air can hold?

warmer air can hold greater amount of water vapor temp directly relates to amt of moisture atmosphere can hold

do large wildfires last days, weeks or months

weeks- months

. When does a hailstone fall to the ground?

when updraft can no longer support

which of the 4 processes is most effective at growing footprint of fire

wind

Are big precipitation events and flooding correlated?

yes

Can the basal surface of a landslide be curved?

yes

can single thunderstorm make multiple tornadoes

yes

is magnitude of lift force sensitive to vertical diff in wind velocity

yes

Does a Flood Pool and the 100-year or Base Floodplain have to cover the same area and what are the implications of flood pools being larger than connected floodplains?

yes flood pool being larger than flood plain leads to people building in this area

Can mass movements produced downstream flooding? If so, how?

yes bc weight supporting pore fluid pressure develops during failure and flow initiation

wildfires produced by lightening strikes in 48 states most common may-sept. is there reason for human caused fires

yes human started wildfires disproportionately occured where fuel moisture was higher higher moisture content in fuel = longer ignition time- difficult for fire

can wildfires create own local weather

yes intense ones can

14. How many people are mapped as being exposed to the 100-year flood using the 'top-down' approach and why the difference?

~ 41 million people Top-down" models fill in the areas that the "bottom-up" FEMA maps miss, such as areas around small streams and across broad swaths of the midwestern and northwestern United States