ATOC 185 Final questions

What does "tsunami" mean in Japanese? Why?

"Harbour wave" because it is harmless until it hits the harbour.

What is the issue with the Canadian radar network for detecting tornadoes?

It is very spotty and has lots of whole in coverage.

What are causes of previous climate change?

Sun's intensity, earth's orbit, thermohaline circulation, volcanoes, ocean currents and snow covers

How much warning time is there for a tsunami?

1 hour per 750 km

What does thunderstorm formation require?

1. A source of moisture. 2. A conditionally unstable atmosphere and 3. A mechanism to trigger a thunderstorm updraft through forced lifting or heating. ("Lim" = Lift, Instability, Moisture)

What are the stages of a thunderstorm lifecycle?

1. Cumulus: warm, buoyant plume with updraft. 2. Mature: both updraft and down draft 3. Dissipating: falling precipitation shuts off the updrafts...all down drafts and system self-destruct

What was Canada's most expensive natural disaster?

2001-2002 drought.

Differentiate between a distant tsunami and a local tsunami.

A distant tsunami is one that propagates across the ocean (there is warning time). A local tsunami is one that results from a nearby earthquake or trigger so there is little warning time.

Explain the differences between divergent, convergent, and transform margins. Give examples of each

A divergent margin is where two tectonic plates are being created as magma is injected in a crack, cooled, and hardened into new crust (Ex. Pangaea: supercontinent which diverged to form plates). At a convergent margin, two plates are being either consumed (oceanic-oceanic) or colliding (continental-continental) causing mountains to form (Ex. Juan de Fuca plate dives beneath the North American plate). At a transform margin, plates simply slide by each other. These occur along strike-slip faults (Ex. San Andreas fault).

What is a fault and where are they found?

A fault is a crack in the Earth where earthquakes occur. Faults can either be active or inactive. They are located around the crust of the earth and most active faults are occur on plate boundaries.

Why will more people be affected by natural disasters in the future?

A greater reliance on fragile infrastructures of increasing vulnerabilities, population growth in coastal floodplains, and global warming influences.

What is a natural disaster?

A hazardous event affecting a community in an adverse way such that essential social structures and functions are disrupted.

What is a tsunami?

A long ocean wave generated by a sudden displacement of the sea floor or ocean mass.

What is a conveyor belt?

A path by which warm and moist air produces precipitation as it overrides the cold air.

What are the three aspects of a prediction/forecasting?

A prediction/forecasting is a statement that a particular natural hazard will occur A. with a given probability B. during a certain time and C. in a specified geographic area.

What is a spreading center?

A spreading centre is a linear zone in the sea floor along which magma rises and from which adjacent crustal plates diverge.

What is Nevado del Ruiz?

A subduction zone volcano. It has high-risk of pyroclastic flows and lahars. There is a large elevation drop so the mud flows very far. Armero is a city in the area that is in high hazard area because it is in the path of the Lahar. People did not realize how far the lahar would flow and did not prepare. Lesson: need effective communication between scientists, politicians, and public.

Differentiate between a tornado warning and a tornado watch.

A tornado warning means that a tornado is believed to be present in the area. A tornado watch provides more lead time and states that conditions are favorable for a tornado. Can be 12 hours in advance.

What is a "trigger?"

A trigger or a lifting mechanism is any mechanism which lifts a parcel of air up the point where it gets buoyant and can produce a thunderstorm.

Why is a tsunami in the open ocean difficult to detect?

A tsunami in the open ocean is difficult to detect because its wave length is so large (hundreds of kilometres) so you wouldn't detect the waves.

What is a tornado?

A violently rotating column of air extending between and in contact with a cloud and the surface of the earth.

Describe the Walker Circulation.

A. Evaporation from ocean moistens atmosphere. B. Trade Winds carry moisture west. C. Moist air rises and feeds rain. D. Dry air cools and sinks.

What is meant by conditional instability?

Air is table to a certain height. However, if a "lifting mechanism" can cause air to rise to a level where condensation is reached, the air becomes saturated and atmosphere becomes unstable.

What are the causes of tsunamis?

All causes revolve around displacement of water. Earthquakes, volcanic activity, landslides, and meteors.

Why do scientists agree that climate change is human induced?

All factors that influence climate change are staying constant except for the increase in GHGs and the temperature is increasing. Therefore, increase in GHGs is causing global warming.

Where do all tornadoes form?

All tornadoes form in thunderstorms which can be found in A. Landfalling hurricanes B. Within supercell thunderstorms or C. In squall lines, often located ahead of cold fronts.

What is a pyroclastic flow?

Ash falling downwind of the volcano (fragmented magma). It is not lava but actually particles colliding. The flow follows gravity so avoid valleys! Can have a devastating impact because flow can reach very far from the volcano.

What is the Saffir-Simpson Intensity Scale?

Assesses intensity of hurricanes. Range is from category 1 to 5. Measures wind speed and storm surge.

Explain the differences between Basalt Lava, Pahoehoe Lava, Aa Lava, and Fire Fountaining.

Basalt Lava: low silica content, high temperature, quite fluid but stickier than maple syrup. Pahoehoe Lava: smooth, ropy lava, fluid-like texture Aa Lava: blocky surface, cool

Why do the countries that emit the most CO2 not suffer the most from climate change?

Because CO2 mixes well with atmosphere the emissions are equally distributed throughout the world.

Why is climate change not a "classic cost-benefit analysis?"

Because the benefits and costs are being carried by different groups. North America and Europe have most CO2 emissions (benefits) but are harmed the least. Developing countries, which do not produce much CO2 are being harmed the most (costs).

What is Cascadia?

Cascadia is a locked subduction zone on the Pacific coast capable of producing M9 earthquakes. It is seismically quiet because the subduction is stuck but it is building stress.

What is Cascadia?

Cascadia is a subduction zone with the potential of a magnitude greater than 8 earthquake so there is a danger of a locally-generated tsunami.

What are the five types of volcanoes?

Cinder Cone, Caldera, Shield Volcano, Stratovolcano, Lava Dome.

Describe and each type of volcano.

Cinder Cone: simple volcano built from blobs of lava ejected from a single vent. They are basaltic and erupt once. Stratovolcano: built of layers of lava, ash, and volcanic debris. There are alternating layers of lava and pyroclastics. They occur at subduction zones. Shield Volcano: built from outpouring of fluid lava flow, broad, gently sloping, mainly basaltic flow. Calderas: large depressions created by collapses of volcanoes and removal of magma beneath volcanoes, causing ground to collapse. They erupt repeated and can keep becoming more depressed. Lava Domes: circular dome of lava which forms because of viscosity of lava (toothpaste analogy), can create pyroclastic flows.

How has climate change increased the impact of storms?

Climate change has caused a rise in sea levels which increases the impact of storm surges.

Why is the Earth habitable?

Combination of the location with respect to the sun and the greenhouse gases in the atmosphere. Factors: surface temperature, surface pressure, major greenhouse gases, temperature if no GHGs, actual temperature, change in temperature due to GHGs

Why do tornadoes with smaller radiuses of rotation have faster wind speeds?

Conservation of angular momentum: r(wall) x v(wall) = r(tornado) x v(tornado). Therefore, the smaller radius of rotation, the faster the wind speeds (decrease in radius must be compensated by increase in velocity to conserve momentum).

What is Coriolis Force?

Coriolis force is the force that acts perpendicular to the movement of a mass moving in a rotating system. It deflects objects in the Northern Hemisphere to the right.

On a sounding graph, what color is the DLR line? ELR line?

DLR line is green. ELR is purple.

What is proxy data?

Data gathered from natural recorders of climatic variability.

How is the destructiveness of an earthquake determined?

Destructiveness of an earthquake depends on magnitude, distance to epicenter, depth, strength of buildings, and nature of soil/foundation on which the structure is built.

How is volcano explosivity determined?

Determined by A. Silica content and B. Gas content of magma.

What is Dew Point Temperature?

Dew Point Temperature is the temperature at which air can no longer "hold" the water vapour mixed with it and must condense into liquid water.

How does volcanic activity affect tsunami generation?

Displacement of rocks (Ex. Submarine Caldera Collapse, entrance of pyroclastic flows in water, Debris Avalanches) results in a displacement of water.

How do volcanoes form at divergent boundaries? Subduction zones? Hot spots?

Divergent Boundaries: mantle rises and melts, producing magma which erupts as basaltic lava flow. Subduction Zone: subducted oceanic plates heat as they plunge. Volcanoes form parallel to subduction zones. Hot Spots: magma from deep within mantle moves up. Hot spots are stationary relative to tectonic plates.

How are tree rings used to assess climate change?

Each ring represents on growing season so we can use the variability in the width of these rings to compare strengths of growing seasons, which depend on temperature and precipitation. Problems: you can only look back as far as the tree is old (<1000 years) and sometimes trees are in bad form and difficult to assess.

What is El Nino?

El Nino is the warming of the waters in the equatorial Pacific, resulting in Southern Oscillation.

What are the three requirements of a hurricane?

Enough Coriolis Force to develop a low pressure system, warm SSTs, and low vertical wind shear.

How is aviation affected by volcanoes?

Eruption column gets in the path of airplanes and can clog engines or blind pilots.

What is a flood basalt?

Flood Basalts can be very large and form lava plateaus. They occur over millions of years and can cause mass extinctions.

What are tsunami hazards?

Flooding, impact on coastal structures, force of waves remobilizing objects, drawdown

What is a Lahar?

Flows of water and loose volcanic debris, common at ice and snow-clad volcanoes.

Describe tornado forecasting.

Forecasting is based largely on the recognition of the patterns which are conducive to tornado formation. We cannot pinpoint locations because process is random and are for generalized regions with probabilities of events.

When do freezing rainstorms occur?

Freezing rainstorms occur when supercooled rain falls onto objects and freezes.

What is the deadliest cyclone in history? Why is this location prone to cyclones?

Great Bhola Cyclone (1970) in Bangladesh. Bangladesh has a high population density in low elevation areas and the storm surge was quite high.

How did climate change impact Europe in 2003?

Heat wave. Land surface temperatures were up to 100C higher. Elderly people suffered mostly due to a lack of air conditioning and mobility (Note: AC is not a solution because electrical grids are fragile during heat waves). Impacted agriculture and forestry.

How does global warming affect extreme events?

Higher Global TemperaturesMore evaporationMore water vapour in atmosphereHigher moisture content (which results in more extreme events).

Explain the difference between hurricanes, cyclones, and typhoons.

Hurricanes: Atlantic and Eastern Pacific Ocean, Typhoons: Western Pacific Ocean, Cyclones: Indian Ocean

How are ice-cores used to assess climate change?

Ice cores are useful to assess climate hundreds of thousands of years ago, but this is still a small amount geologically speaking. Within each layer of the ice core are trapped air bubbles which can be analyzed to detect the amount of carbon dioxide present. There is a direct correlation between the amount of carbon dioxide and the temperature (when CO2 goes down, temperature goes down).

What must be present for water to freeze?

Ice nuclei (dust, soot, etc.) must be present. Ice nuclei are most effective at producing ice at temperatures less than -100C.

Where do ice storms occur?

Ice storms occur to the north (cold) side of a warm front, west of a surface cyclone and/or the cold side of a cold front in a cold-air dome associated with a high pressure system. Freezing rain is most heavy on the cold side of the warm front, and less heavy on the cold side of cold front or the edges of the cold front in a Cold Air Dome. Severe events combine a cyclone to the south and a cold air dome to the North.

What is a Debris Avalanche?

If a volcanic foundation is weak, it may collapse, causing an avalanche.

Describe the 1900 Galveston Hurricane.

In Southeastern United States. The worst US natural disaster. 7 m surge. Low elevation city. However, after this event, the city built a seawall which mitigated the effects of another hurricane just 15 years later.

Explain the development of an ice storm around a cyclone.

Initially, a stationary front (or boundary) separating warm air to the south from cold air to the North. Wave on the front form as an upper-level disturbance embedded in the jet stream moves over the front, resulting in a "kink" where the wave is developing. As wave intensifies, both fronts become better organized. The warm air overrides the denser cool air to the North.

Define instability in terms of thunderstorms.

Instability: if an air parcel is shifted from equilibrium, it will accelerate away from original position (tennis ball experiment). In terms of thunderstorms, there is warm air at the surface and cold air aloft (opposite of Ice Storms).

What was the impact of Hurricane Andrew?

Insurance companies went bankrupt so it lead to the reinsurance industry. Luckily, the hurricane hit the cheap real-estate so the economic losses weren't too bad.

What are trigger mechanisms of hurricanes?

Intertropical Convergence Zone (ITCZ), Easterly Waves, and Middle Latitude Cold Fronts. ITCZ is the area encircling the earth near the equator where the SE and NE trade winds come together. It migrates with the sun towards the summer hemisphere.

Why is tree planting on coastal areas good mitigation for tsunami waves?

It increases Manning's coefficient in the inland penetration formula because it requires more force for the tsunami to penetrate deeper.

How was the term "El Nino" coined?

It was coined by fishermen. It means "Christ Child." During El Nino years, the fishing industry declines so fishermen can spend more time with their families, hence the term "Christ Child."

Why is Montreal vulnerable to ice storm?

Its location in the Saint Lawrence River Valley which traps cold air flowing into area from anti- cyclones. This cold air then lifts warm air, resulting in an environment favorable for freezing rain.

How does Hurricane Camille's storm surge compare to Katrina's? How about their impacts?

Katrina's landfall was category 3 but its storm surge was more than Camille's because although its winds had weakened, its surge was still 8.4 m (compared to Camille's 7.3 m).

Why is Bangladesh especially vulnerable to tornadoes?

Lack of warning system and population density.

Define lapse rate. Differentiate between environmental lapse rate, dry adiabatic lapse rate, and moist adiabatic lapse rate.

Lapse rate is the rate at which air temperature falls with increasing elevation. Measured in degrees/kilometer. Environmental Lapse Rate is the rate of decrease of temperature with altitude in the stationary atmosphere. Dry Adiabatic Lapse Rate is the rate at which dry air cools with increase in altitude (approximately 100C/km). Moist Adiabatic Lapse Rate: The rate at which moist air cools with increase in altitude (approximately 60C/km).

How do thunderstorms cause hurricanes?

Large scale convergenceIncrease in surface windsIncrease in heat and moisture in the ocean and airCentral low pressure in eye with warm core created by subsidence.

What are three types of lifting?

Lifting by a front, lifting by a gust front from a thunderstorm, and lifting by a sea-breeze front.

What are the critical issues of natural disasters?

Linked hazards, intelligent choices, resilience and preparation.

Explain the impacts of earthquakes.

Liquefaction (wet, unsolidated soils and sediments especially vulnerable to aftershock), tsunamis, aftershocks, landslides, fires, personal loss.

What are some safety measures for tornadoes?

Listen to media, move to designated shelter such as abasement or an interior room (as many walls between you and the tornado as possible). If outside, go to low elevation.

What are some mitigation techniques for ice storms?

Listen to the media, close off unneeded rooms, stuff towels in cracks of doors, cover windows, eat to maintain energy, stay hydrated, and wear layers.

Why do tornadoes cause fatalities comparable to other weather disasters?

Little warning time and catastrophic nature of damage.

Why was the Tohoku earthquake not as devastating as it could have been?

Low population density in the area affected.

Why is the Moist Adiabatic Lapse Rate not constant?

MALR is variable but always less than DALR. As the moist air parcel rises, it becomes saturated (holding as much moisture as possible) and condensation occurs, resulting in a release of latent heat. MALR is not constant because the rate of condensation changes with height.

How does higher silica content affect magma?

Magma with higher silica content is more vicious and has a higher viscosity (sticker/thicker).

Describe the Boxing Day 2004 Indian Ocean Tsunami.

Magnitude 9-9.3 earthquake triggered the tsunami. The earthquake's epicenter was on coast of Indonesia. 1⁄4 million fatalities with global propagation, affecting as far as BC. Took 1-2 days to hit North America (distant) so plenty of warning time but none for Indian Ocean (local).

Why are strike-slip faults less likely to generate a tsunami?

Mainly vertical crust movements cause displacements so strike-slip faults are less dangerous.

How did El Nino affect Indonesia in 1997-1998?

Massive wildfires, releasing lots of carbon dioxide and pollution.

How is volcano destructiveness measured?

Measured by the Violent Explosivity Index. Caldera-forming eruptions are the highest (ex. Yellowstone).

What is the Doppler Radar? How does it work?

Measures wind speed of tornadoes and hurricanes. Points a beam at the stormWind has an impact on beam's wavelengthradar detects wind speed by calculating difference in frequency and direction.

What is a mesocyclone?

Mesocyclone is the circulation that could spawn a tornado due to a rotating updraft.

Define "mitigation."

Mitigation is efforts to reduce the effects of a natural hazard on a community.

Describe volcano mitigation techniques.

Monitor gases, monitor seismicity, and study geology.

How does the rigidity of the earth's surface affect a tsunami?

Seismic movement = slip x fault area x rigidity of rocks so displacement can increase if decrease in rigidity.

Why is Montreal a seismically active region?

Montreal is not located near a plate boundary. However, it is a seismically active region because of its position in the Saint Lawrence River Valley. The valley may have once been a plate boundary which left behind rift zones

Where are the most dangerous hurricanes located? Why?

Most dangerous tropical cyclones are located in Asia due to population density in low elevations.

Where do earthquakes occur?

Most earthquakes occur when ground is breaking in a brittle fashion along a fault and in the crust closest to the surface because the crust is too hot deeper down.

Where and when do most hurricanes occur?

Most hurricanes do not occur at least 50 away from the equator and rarely poleward of 259 poleward. Hurricanes do not occur in cold waters. Two-thirds of hurricanes occur in North America. Hurricanes tend are more frequent in the months of AugustOctober (because SSTs are highest) but there are significant inter-annual period of variability.

Where do the most powerful earthquakes occur? Why?

Most powerful earthquakes occur along convergent boundaries because of the friction and stress being built up from subduction zones.

What are the areas most prone to tsunamis?

Most prone areas are those associated with earthquakes and volcanoes, mainly in subduction zones (most in Pacific Ring of Fire).

Where do most tornadoes occur? Why?

Most tornadoes (85%) occur in North America because geography of North America is favourable for tornadoes: warm-moist air source, cold air source, and mountain ranges oriented North-South.

Where do most volcanoes occur?

Most volcanoes occur at plate boundaries, under the ocean (mid-Atlantic Ridge) and the Ring of Fire.

Explain the differences between normal (vertical), reverse (thrust), and strike-slip (lateral) faults.

Normal (vertical) faults are the result of tensional forces - being pulled apart - and occur along divergent margins. Reverse (thrust) faults are caused by horizontal compression and occur at convergent margins. Strike-slip (lateral) faults are a mini-version of transform margins. They are either left-lateral (sinistral) or right-lateral (dextral). The movement is in reference to the upper block.

What is the Southern Oscillation index?

Normally, Darwin (Northern Australia) has warm waters and Tahiti (Southern Pacific) has colder waters. These locations have a large longitude difference but a small latitude difference. The SOI measures the pressure at these two locations, which are indirectly proportional, resulting in a balance. SOI = Tahiti pressure - Darwin pressure. SOI > 0 = La Nina. SOI < 0 = El Nino.

What is an inversion? How does it form?

Normally, temperature decreases with elevation but during freezing rain, temperature increases with elevation near surface and decreases with elevation farther above. Inversion is a layer in which temperature increases. Inversions form from warm and moist air flowing above dome of cold air which hugs the ground and does not allow warm air to penetrate the ground.

Where do most tornado-related fatalities occur in the US? Why?

Not in tornado-alley but rather just south of it because they do not have proper warning systems and are unprepared.

Is the number of fatalities from tornadoes increasing, decreasing, or stable?

Number of tornadoes is slightly increasing but number of fatalities is decreasing.

What is thermocline?

Ocean temperatures decrease with increasing depth. Thermocline is the region from 0-1500 m below sea-level, where the ocean temperature decreases very rapidly. After this region, the change slows down.

What are issues with assessing climate change?

Only 150 years of record - insufficient to document natural climate variability - and inconsistency of data.

What is supercooled water?

Supercooled water is water that exists below 00C. 00C is a melting point but not necessarily a freezing point.

What is freezing rain?

Supercooled water that freezes upon impact.

What is wave run-up dependent on?

Wave run-up is dependent on water depth, sea floor profile, and the shape of the coastline (continuous or irregular).

When is the peak or tornado frequency in US? Why?

Peak of tornadoes in US is May and June because thunderstorm formation is most active in tornado alley in May. Tornadoes also peak in evenings because air temperature is warmest and air tends to be better mixed so wind speed is higher.

What does ice storm severity depend on?

Persistence, intensity, phase (supercooled), and location.

What caused the severity of the 1998 Ice Storm?

Persistence: lasted five days. Intensity: Hundreds of millimetres of precipitation across. Phase: the supercooled water froze upon impact, resulting in widespread power outages as utility poles and power lines were damaged. Location: Saint Lawrence River Valley trapped cold air in the region, increasing its severity.

How do subduction zones generate tsunamis?

Plates are stuckOverriding plate distortsStuck area ruptures, releasing energyTsunami spreads due to displacement

Explain the Disaster Assistance Response Team (DART).

Pressure sensors at the bottom of the ocean which can detect movement and generation. They are located around the Pacific Ring of Fire to detect pressure change.

What are the economic impacts of cyclones?

Rebuilding, evacuation costs, impact on energy production, coastal erosion

What is a recurrence interval?

Recurrence interval is the average time between the occurrence of two events of similar magnitude.

What are the impacts of El Nino on American weather?

Reduction in Atlantic hurricane activity because of strong upper level winds that produce too much wind shear for a hurricane to exist.

Explain the differences between Richter Magnitude and Moment Magnitude.

Richter Magnitude measures the amplitude of ground shaking and is a logarithmic scale. Moment Magnitude measures the size of the earthquake in terms of energy released.

What are the differences between risk, hazard, and vulnerability in terms of natural disasters?

Risk is the probability of loss as a result of a natural event. Hazard is the potential threat to humans and their welfare. Vulnerability is the potential loss, or degree of loss from the event (0 = no damage, 1 = total loss).

What are the preferred areas for freezing rain in Canada?

Saint Lawrence River Valley, Newfoundland, Eastern Great Lakes, Eastern valleys of Appalachian Mountains, river and mountain valleys in general. Cold air migrates from North but Rockies act as a boundary so cold air only to the East of them.

How seismic hazard determined?

Seismic frequency determines risk and population density determines vulnerability.

Why don't single-cell/air-mass thunderstorms produce tornadoes?

Single-cell thunderstorms do not produce tornadoes because 1. Updrafts are supressed by weight of the water and 2. No inherent rotation to work with.

What are some myths about tornadoes?

Skyscrapers prevent tornadoes, highways are a safe place to shelter, if condensation doesn't reach ground, then the tornado can't do damage, tornadoes always move from SW to NE.

Describe the atmosphere during each of the following events: snow, freezing rain, ice pellets.

Snow: Deep cold layer throughout. Precipitation stay as snow throughout passage. Ice Pellets: cold layershallow warm layercold layer. Snowpartial meltingsupercooled waterrefreezingice pellets. Freezing Rain: cold layerdeep warm layershallow cold layer. Snowcomplete meltingsupercooledfreezing upon impact.

Describe the Greenhouse Effect.

Solar radiation passes through the clear atmospheremost radiation is absorbed by earth's surface and warms itsome radiation reflected by the earth and atmosphereinfrared radiation is emitted from the earth's surfacesome infrared radiation passes through atmosphere and some is absorbed and re-emitted by GHG molecules, warming the earth's surface and lower atmosphere.

What is the source of moisture for thunderstorms in North America?

Source of moisture is Gulf of Mexico and cold dry air comes from Rockies.

What locations are most vulnerable to climate change? How is vulnerability measured?

Southeast Asia, Africa, and Latin America are most vulnerable. Vulnerability is a product of hazard (climate change) and number of people affected (population density).

Describe Southern Oscillation.

Southern Oscillation is the sea-saw variation of surface pressure between western and eastern equatorial Pacific. Equatorial eastern winds weaken and strengthen alternately in response to Southern Oscillation.

Describe the tornado breakout of November 10/11, 2002.

Southwestern US. 88 tornadoes in Alabama and Pennsylvania alone. The outbreak was unusual for November. It shows large-scale control on location of outbreaks.

How is the speed of a tsunami calculated?

Speed = wave length ÷ wave period

How is the stability of the atmosphere related to the changes of temperature with height?

Stability of atmosphere is directly related to the changes of temperature with height. As a parcel of air rises, it moves into regions of lower pressure and expands: the same number of molecules covers a large area so air in parcel must do work to inhabit that volume, resulting in a lower kinetic energy and a temperature decrease.

When is the atmosphere stable, neutral, or unstable?

Stable: ELR < DLR. Neutral: ELR = DLR. Unstable: ELR > DLR

What are the hurricane hazards?

Storm srge, wind damage, heavy rain, and associated tornadoes.

What is storm surge? How is the level of surge determined?

Storm surge is the rising of the sea as a result of atmospheric pressure changes and winds associated with a storm. The level of surge is determined by the high and low tides and the slope of the continental shelf.

How is the strength of a tornado determined?

Strength of a tornado is determined through the damage it causes.

What is subsidence?

Subsidence is another mechanism of warming in tropical cyclone centers. As the air in the eye sinks, it warms due to compression.

How does El Nino affect trade winds? What is the significance of this?

Surface winds are typically from the east in the tropics and surface currents bring cool water up the west coast of South America. This results in cold water on the west coast of continents and warm waters on the east coast of continents. However, during El Nino, trade winds are weakened so this huge amount of water comes back and disrupts weather patterns.

Where can climate change be seen?

Temperature changes or sea level changes.

Where are the seismically active regions in Canada?

The Canadian Shield is seismically quiet but areas such as Vancouver and Montreal are prone.

What is the Elastic Rebound Theory?

The Elastic Rebound Theory states that after rupture, the rocks generally return to their original shape and stress level. However, sometimes there is leftover stress. There exists a balance between the stress and friction on the fault. When the stress exceeds the friction, the fault fails.

What is the Enhanced Fujita Scale?

The Enhanced Fujita Scale is a more precise and robust version of the Fujita Scale. It classifies F0- F5 damage across 28 different types of damage indicators (buildings, trees, etc) because a "one size fits all" approach (Fujita Scale) doesn't work because the scale needs to evaluate strengths and weaknesses of different constructions.

Describe the structure of a hurricane.

The Eye: hurricane's center, calm, clear area of sinking air and light winds. The Eyewall: ring of tall thunderstorms and strongest winds. A change in the structure of the eye and eyewall affect hurricane intensity. The Eyewall can grow or shrink in size. Rainbands: curved bands of clouds of thunderstorms that spiral away from the eyewall.

What is the Gutenberg-Richter Relationship?

The Gutenberg-Richter Relationship shows that there are many small earthquakes but very few large ones.

What is the Mercalli Index?

The Mercalli index measures the effect of earthquakes on structures. The value depends on proximity and depth of the earthquake. It ranges from 1-12.

What is tornado alley?

The Northeast/Southwest orientation of strong fronts travelling across Central US in spring and of the upper-level jet stream Includes states such as Texas, Oklahoma, Kansas, Iowa, Florida.

What is the Pacific Ring of Fire?

The Pacific Ring of Fire comprises the subduction zones encircling the Pacific Ocean. It is characterized by subduction zones, violent earthquakes, and volcanic eruptions. The friction from these subduction zones causes many powerful earthquakes.

Describe the San Francisco 1906 Earthquake.

The San Francisco 1906 Earthquake occurred along the San Andreas Fault, which is a series of right-lateral strike-slip fault systems. Rocks on either side of the fault are different which shows the displacement of the ground. Many fires broke out after the earthquake. This will likely reoccur due to the fault's prolonged seismic inactivity (rebuilt stress). However, much of the population is still in that same area (stable vulnerability).

What is the difference between the focus/hypocenter of an earthquake and its epicenter?

The focus/hypocenter is where the earthquake starts inside the earth. The epicenter is the surface directly above the focus/hypocenter.

What are the largest recorded earthquakes?

The largest recorded earthquakes are Chile 1960 (9.5), Alaska 1964 (9.2), Indonesia 2004 (9.1- 9.3), Japan 2011 (9.0), and Kamchatka 1952 (9.0)

How does climate change affect cyclones?

The number of cyclones is constant at 100 but the number of severe cyclones (cat 3 or more) is increasing because SSTs are increasing (there is a correlation between SSTs and hurricane strength).

What happens to a tsunami wave as it approaches the shore?

The waves pile up, decreasing velocity and wavelength but increasing amplitude.

How does El Nino affect extreme events?

There is an increase in the ocean surface temperature which increases the frequency of extreme events such as hurricanes and tornadoes which require a warm, moist atmosphere.

Why was the 2015 winter in Montreal so bad?

There were persistently cold temperatures (very few days that went above freezing).

Why are submarine landslides especially dangerous?

They are generated by earthquakes so they cause additional water displacement

What do hazard maps do?

They identify active volcanoes. Volcanoes are said to be active if they have erupted in the past 1000 years. It also incorporates population density which adds to hazard. This is said to be an arbitrary definition because if a volcano erupted 10010 years ago, it is technically not active.

Describe forced lifting.

This is lifting by a front. Advancing cold air behind a cold front forcibly receding warm air ahead of cold front, resulting in cloud development. This occurs along the front range or Rockies.

Describe the hurricane lifecycle.

Tropical Depression: first appearance of a lowered pressure and wind rotation, disorganized Tropical Storm: now has a name, intensified tropical depressionMinimum Strength Hurricane: surface pressure drops, pronounced rotation around core, bands of clouds and precipitation around the eye, 74 mph+ winds speeds

What do tsunami hazard maps indicate?

Tsunami hazard maps include inundation zones and evacuation centers.

Differentiate between tsunami propagation, inundation, and drawdown.

Tsunami propagation is the wave travelling through the ocean. Inundation is the tsunami landing at shore. Drawdown is the fall in sea level prior to the arrival of a tsunami, which often attracts people to the beach.

What does tsunami response require?

Tsunami response requires good emergency planning and preparation, an educated and trained public, and the efficient dissemination of information.

Rank the following from least to most difficult to predict: earthquake, tsunami, hurricane

Tsunami, hurricane, earthquake

Describe the process of upwelling.

Upwelling locally cools surface water temperatures by bringing cold water up from underneath. However, during El Nino, warm waters supress the upwelling of cold, nutrient-rich water. Easterly winds weaken and warm water of western Pacific comes back to East because the trade winds are too weak to sustain the tilted sea level (due to upwelling).

How do earthquakes cause tsunami?

Vertical curst movement causes a displacement of water.

What is Cold-Air Damming?

Warm air overrides cold air and creates inversion and advection - responsible for precipitation. Cold air can get trapped on the slopes of mountains (ex. Rockies).

Describe a warm core.

Warm moist air moves over the oceanWater vapor rises into atmosphereWater cools and condenses into liquid dropletsCondensation releases heat into the atmosphere, making air lighterWarm air continues to rise with moist ocean air taking its place and creating wind

What is a hurricane?

Warm-core, low-pressure, without attached fronts, develop over tropical or subtropical waters, organized circulation with winds of 120km +

What are some primary greenhouse gases?

Water vapour, Carbon Dioxide, Methane, Nitrous Oxide, Ozone

Describe the following terms: wavelength, trough, wave height, wave period and amplitude.

Wavelength: distance from one peak to another. Trough: lowest point of wave. Wave Height: distance from trough to peak. Amplitude: distance from peak to still-water-line. Wave period: time it takes for a pair of wave crests to pass a certain point.

What are the global consequences of El Nino?

Wildfires and drought in dry areas (Australia/Indonesia) and flooding and hurricanes in wet areas (Eastern Pacific and South America). Flooding can bring water-borne diseases.

How have human actions increased vulnerability to natural disasters?

Wildfires, building towns near natural-disaster prone areas, hotels on beach front, mega-cities in coastal areas.

How does wind shear help single-cell thunderstorms produce tornadoes?

Wind shear can fix both of the above conditions. Updraft tilts rotation from horizontal axis to vertical axis. Updraft is tilted by the shear, removing updraft from precipitation area. Now single-cell thunderstorm is a supercell and has a mesocyclone.

What is wind shear?

Wind shear is the variation in wind velocity occurring along a direction at a right angle to wind's direction and exerting a turning force.

Where are a hurricane's winds strongest? Why?

Winds are strongest at the right of the track because the system is spiralling counter-clockwise.

Is climate change a natural disaster? Why or why not?

Yes and no because it is not a single event but still has severe consequences.

Can El Nino be predicted? If yes, how? If not, why?

Yes, 6-8 months in advance by using SST anomalies.