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279 Cards in this Set
- Front
- Back
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Hurricane
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one of the big killers along with earthquakes
a lot of economic losses |
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where are the most fatalities linked to hurricanes
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bangladesh
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Why does canada not suffer from many hurricanes
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because we are far enough north
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1900 galveston hurricane
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number of canadians killed in texas
- 80-100 fatalities atlantic coast |
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hurricane hazel
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1954
atlantic coast people died from the flooding caused by the rainfall |
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conditions necessary for hurricane formation
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1. seawater greater then 27 degrees in upper 60 m of ocean
2. air must be warm and humid 3. upper level winds should be weak i.e no wind shear 4. coriolis effect is required |
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why does the water have to be above 27 degrees and 60 m thick to form a hurricane
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- once a storm gets going the wind blows, big waves, water mixing, when water cools the storm stops
- has to be a thick layer so when the waves get going the water stays warm and doesn't cool off |
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where do hurricanes form
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over water
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what powers a hurricane
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the latent heat of condensation
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why can't there be wind shear for hurricanes
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a hurricane is an organized structure from sea water surface to tropopause: so need entire troposphere to not have windshear
- strong wind shear will break up a hurricane - opposite of a tornado |
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why can't hurricanes form at the equator
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- there is no coriolis effect
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can hurricanes cross the equator?
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no - because no coriolis effect
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Formation of a hurricane
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- air goes in as LOW PRESSURE IN NORTHERN HEMISPHERE so winds turning to the RIGHT as they come in rotating COUNTER CLOCKWISE
-as it rotates and moisture comes in uplift in flow and as it rises the air cools off and so it reinforces the rising -spirals upwards until it gets up to the tropopause -once it gets to the tropopause the air goes out as HIGH PRESSURE |
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what happens when air sinks back down to the middle of the hurricane the "eye"
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the air warms up from depression and so the eye is almost cloud free
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what part of a hurricane has the most intense wind speeds and rain fall
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outside the eye
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what is the typical eye diameter
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20-30 km
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why does the air organize like so for a hurricane
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- the density of air in our atmosphere
- source of energy - height of tropopause - stable configuration of releasing energy -reduced friction in fluid flow -not the only planet with cyclonic storms |
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is it warmer or cooler in the eye of the hurricane
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warmer
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what is pressure like at the eye
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extreme low pressure
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Four forces that control the circulation of hurricane surface winds
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1. pressure gradient
2. coriolis 3. centrifugal forces 4. friction |
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what is the net balance of the forces that control the circulation of a hurricane
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surface winds
- spirals inward toward the centre of the storm |
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isobar
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a contour of equal pressure at arbitrary distance from the eye
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what kind of air is required for a hurricane
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warm humid and moist
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why is warm humid most air required for a hurricane
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because hurricanes are powered by the latent heat of condensation as water vapour condenses to drops
- hurricanes pull this heat out of the surface water of the ocean not just the air |
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how long can a hurricane run for
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as long as its over warm water
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where do hurricanes differ from tornados
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- air rising around hurricane is releasing energy but the winds rushing in also evaporate some of the surface later of sea water pulling energy out of warm water
- hurricanes almost all energy out of the warm layer of the ocean rather then the moist air - after it pulls the energy out of the ocean it is then powered by latent heat of condensation |
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Hurricane Gloria
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- off the east coast US sept 1985
- the maximum cooling is just to the right of the track - why hurricanes only south because of warm water |
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are hurricanes windstorm velocities as great as a tornados?
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no
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why the energy of hurricanes comes out mostly to the right
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- they are formed and pushed by prevailing winds
- prevailing wind speed adds on to the right side and is subtracted on the left side |
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Does wind or water kill people in a hurricane
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water
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what is in the centre of a hurricane
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a mound of water - the deadliest part of the hurricane
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what creates the mound of water in a hurricane
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1. low atmospheric pressure
2. centralling rushing converging winds |
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how does low atmospheric contribute to the mound of water in a hurricane
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the pressure in the centre of a hurricane is 10% less then the air around it so the surface of the ocean rises up about a meter because there isn't air pressure pushing down on it
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how does centralling rushing converging winds contribute to a hurricane
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- winds push water up into a hill
- how big the mound is depends on velocity of the winds - winds can push water up to 9 m high |
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how big can a mound of water get
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1m (from low atmospheric pressure) + 9M (from winds) = 10M
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where is the maximum surge height
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always to the east/right of where the eye is
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how big are surges compared to whole storm
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100-200km across compared to 500km of whole storm
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what is optimistic bias
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people tend to think that others have a more likely chance to have bad things happen to them than themselves
- as in hurricane sandy |
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why aren't people prepared for hurricanes?
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- people prepare for the wrong thing (winds instead of water)
- thought wind most dangerous but it was actually flooding - people who actually have had bad experiences with hurricanes are more prepared then those who haven't |
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how to motivate preparedness
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- have mandatory evacuations
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2008 hurricane mike
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people died because they elected to stay when it was a mandatory evacuation
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typhoon haiyon
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-asia
-conditions similar to a tsunami -8000 dead -philipines -category 5 |
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who has the highest death tolls from hurricanes
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bangladesh because of low land by sea and high population density
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when do hurricanes occur
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over the entire year in the atlantic
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what are the most common months for hurricanes
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august, september, and oct
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where is the warmest weather for hurricanes
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southern atlantic
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what determines the amount of hurricanes
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the amount of warm water
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what part of the world has most hurricanes in the pacific
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western pacific 30%
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where is the largest amount of warm water on earth
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western pacific
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what happens to the amount of hurricanes in a El nino season
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there are less hurricanes because concentration of warm water in western pacific not as strong
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Why are hurricanes predictable
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they have typical paths, typically form off the cape of africa, turn up the gulf or up coast and travel around the bermuda high
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what is the high pressure zone that hurricanes like to travel around
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bermuda high
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what happens when the bermuda high is small
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hurricanes stay over atlantic and miss north america
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what happens when bermuda high is large
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may guide the hurricane to eastern coast of USA or Canada
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what happens when the bermuda high travels south
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it directs hurricanes to the carribean sea and to the gulf of mexico
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when are hurricanes fewer
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- el nino is present (due to windshear)
- cooler sea surface -sahel has drier summer |
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when are hurricanes frequent
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- el nino is absent
- warmer sea surface -sahel has wetter summer |
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how does sea cooling make a difference to hurricanes
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1 degree can make a difference
- these days measured with satellites |
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how does el nino affect hurricanes
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changes in atmospheric circulation as there is more wind shear and less warm water
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1951 - 1960 major hurricane trends
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-more water = more property damage
-run up the east coast of the united states |
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1961 - 1980 major hurricane trends
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- went from east coast to gulf
- area of significant hazard switched because these patterns are statistically significant patterns that reflect climate shift |
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how do climate shifts affect hurricanes
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moves hurricane path from one place to another
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hurricane predictions
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- all hurricane predictions have current position of storm and 24 hour updates of where they think its going
-tracked 7 days out |
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track errors
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the predictions get better as time goes on 2 day or 3 day predictions dramatically improved
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what does an intensity of a hurricane show
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how high the mound of water is going to be coming ashore
- people getting much better at predicting this |
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hurricane mitch
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- began in carribean
-22 oct 1998 - stalled offshore from the 27-28 - dumped enormous rain in honduras and nicaragua - on nov 3 entered the gulf of mexico -picked up strength over warm water -travelled to great britain - caused mass movements from rain - killed 30 000 people from the debris flow |
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why can hurricanes be very deadly when they bring rain to land
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mass movements
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hurricane juan
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eye went right over halifax
- created mound of water up to 3 M high - near the sea - sea margins affected |
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hurricane hazel
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- went over toronto
- heavy rainfall in toronto -80 people killed in flash flooding -unusal event for canada -largest loss of life in canada from hurricane -neighbourhoods eroded away from the floods |
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hurricane katrina
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-mississippi river and delta
- new orleans has delta between it and ocean - tidal lake - if storm goes up over the lake the water levels go up -1000 fatalities |
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new orleans
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-built on a delta
-sinking land from pulling ground water out - good chunk of new orleans below sea level |
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how has europe adopted defense for hurricanes
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levys to protect the city and stop the water
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what defense did new orleans have from the hurricane
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have sets of dykes in compartmentalized district of the city
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what happened to the levys during katrina
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2 levy failed and thousands of homes flooded
- water went up to the roof of one story homes |
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portrait of katrina victims
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- mostly people above 60
-age rage of the populace was young -victims strongly skewed to old people they didn't have the energy to leave |
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3 things done wrong with hurricane katrina
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1. decision makers did not credit technological info
2. warning/ alert system not present 3. the emergency response not adequate |
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hurricane sandy
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- height predicted well
-manhattan -water ran into subways -accurately predicted -mound of water came ashore at high tide -bad timing |
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who was hit hardest by hurricane sandy
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right side of statin island
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1970 cyclone bangladesh
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- 500 000 fatalities
- largest loss of life bay of bengal because in the north large delta close to sea level -population pressure |
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how has bangladesh handled precautions for hurricanes
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aggressive in building storm shelters
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Cyclone Nagris 2008 Myanmar
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- ~ 150 000 in fatalities
- delta - myanmar military government - warnings all there externally but didn't get to the people - after the fact relief wasn't allowed for water or food for their people |
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trend of floods identified as natural disasters in canada per decade
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trend is increasing
- generally much of the property damage from floods is affecting old structures |
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when do floods occur in canada
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- most march april june
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what is peak month for floods
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april
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why is spring peak for floods
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rain events and snow melt
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decade with most flood fatalities in canada
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1960 because of hurricane hazel
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how many fatalities a year in canada
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approx 1per year
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Drainage basin composed of what 4 sub basins
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1. ephemeral
2. merge into small subs tributaries 3. larger sub tributaries 4. tributaries and then finally run into main streams |
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flood plain
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flat lands bordering a stream and during a flood the stream overtops its banks and inundates the flood plain
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how does a river create a natural levy
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a ridge of sediment is deposited when water spills over the banks and slows down for forming a natural levy
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Flood styles
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1. hydrometeorological floods
- rainfall - snow melt - rain- on - snow - ice jam 2. Natural Dams |
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what are the most damaging situations for floods
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rain snow and ice jams
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what increases infiltration
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1. increasing soil porosity
2. increasing vegetation cover 3. increasing duration of precipitation |
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what increases runoff
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1. increasing amount of precipitation
2. increasing soil saturation 3. increasing slope steepness |
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do you want infiltration or runoff
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infiltration
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the smaller the drainage basin the greater the chance for what
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RAPID RISE
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the bigger the river the longer it takes for what
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water to rise and fall
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what kind of modelling is used for flooding
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empirical modelling because weather is chaotic to predict
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chaos
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the troposphere has convection and the atmosphere is a fluid and convection of a fluid is always turbulent and turbulence is chaotic because you can't analytically predict where they are going to be flowing or how fast
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recurrance interval
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R= (N+1) / M
N= # of years of record M = rank |
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annual probability
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1 / recurrance interval
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city planning and floods
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if you plug flood way with buildings the flood of the same size gets bigger
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what do we do to invalidate empirical modelling of floods
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buildings built in floodway which hold river back and when that happens your model is no longer valid
- same amount of water going to leave into a higher level and a greater area gets wet strategy: build a mound of earth but that still is a dam affecting the flow of the water |
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drainage basin modification
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1. deforestation
-w/o vegetation run off is faster, snow melt changes when you have peak water in river 2. confinement/levee building - built levees along the river so when the same amount of water along river what would of spread out is confined by levees 3. urbanization |
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how do levees fail
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1. erosion/wave attack
2. erosion/overtopping of water 3. saturation weakening/slumping 4. piping |
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what is the simplest way to make levee
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dirt
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levee failed along mississippi in 1993
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- long term weather pattern of air flow from gulf of mexico and rain
-enough to make river high and keep it high for a long time - 100 days -levys 60 years old -change in width of river - water went 12 ft higher then if levy weren't there because of confinement |
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hydrograph
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planners use this to model how a river will respond to a certain event
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rising limbs vs falling limbs of hydrograph
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rising limb always shorter
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Brays Bayou Houston Texas
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- effect of urbanization
- in rural most water soaks into the ground - after urbanization the roods and pavement covering the land prevent infiltration and most rain quickly runs over the surface creating more floods |
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how much civilization affects hydrographs
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- after urbanization much faster rise peak higher and fast fall off
- urbanization dramatically changes characteristics of drainage basins |
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urbanization of drainage basins
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1. impermeable surfaces
2. channelization: storm sewers run water into river 3. robbing ourselves of water- tapping ground for water |
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LA basin
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now dealing with consequences of urbanization
- they still get water from ground water but their surface rainfall is run into the sea - so the ground not restored with water |
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flood frequency
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floods occur more frequently as storm sewers, roofs and pavement increase
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flash floods
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responses to extreme rainfall
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big thompson canyon july 1976
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in 3 hrs 200X more water and there was no vegetation thin soil bare rock,
- rapid runoff - lots of people trapped in their cars and die |
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whats the biggest killer of flash floods
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people driving into them
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Saguenay Region July 18-21 1996
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-flash flood
-north eastern mexico -100 people died |
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1996 st lawrence july
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rocky terrain
-narrow channels -no flat flood plains -town built on rock -nealy a foot of rain in 3 days -also have moisture coming off st lawrence -rainfall triggered flood |
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red river north dakota/ manitoba 1997
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- lake event with flood because the red river flowing north into hudsons bay is slowly rising
-takes a long time for water to go away -levys protected southern part and built flood way channels -protected winnipeg many times |
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river avulsions
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the river has built the levy and the bigger flood erodes that levy and builds a new channel
-refers to it jumping out of the natural confined channel it has built for itself |
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`eastern china
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-huang river has been called the most destructive thing on the planet because of its avulsions and highly densely populated area
-yellow river |
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2 biggest floods since history of calgary
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1. 1879
2. 1897 |
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total damages of the 2013 flood
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5 billion dollars
-biggest case of insured losses in canadian history due to any natural disaster |
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things needed for big flood
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1. melting snow
2. big storm |
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when is max snow pact
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in may
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when is the prime month for flooding
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june because of storms and rapid snow melt
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why was flood so big in 2013
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had a storm that stalled in place over kan valley
- the epicenter of the storm was SW of kan |
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1998 alberta fire |
wild fires when prairies are dry this one came late december - the snow came late dead grass get fire |
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slave lake fire may 2011 |
700 Million in insured losses arson north of the province no lives lost wind made the fire jump the fire grounds and burned the town of slave lake there was a good evacuation plan |
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wild fire causes 2009 |
humans caused 5 times more fires than nature but the areas burnt are aprox the same human causes 85% |
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us wild land fires by decade trends |
the number of fires more or less the same, the number of acres burned DROPPED dramatically by factor of 10 |
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why has the area of acres burned by wildfires dropped |
the greater capability to identify and put out the fire quickly |
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value of property destroyed by forest fires in canada |
a lot of the economic losses are wood harvest value |
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area burned across canada trends |
spikes up and down in terms of economic losses and dry years the lightening started fires burn more area than human caused fired |
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why does lightening wild fires burn more than a human caused fire |
Less likely to be seen and put out so it burns a larger area |
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cochrane and matheson fire 1916 |
northern ontario wind came up and pushed fire in northern ontario and over ran some small communities -more than 200 people died |
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fire of 1925 new brunswick |
burned from one fire but the number of fatalities are unknown - one of the two or three largest fires recorded in north america since europeans have settled |
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3 parts to the fire triangle |
1. fuel 2. oxygen 3. heat |
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energy barrier - fires |
When it is hot enough fuel breaks the barrier and reacts with o2 and releases the energy |
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combustion |
C6H12O6 + 602 -> 6CO2 + 6H20 + heat |
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everything we burn on the planet is powered by what |
the sun |
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what is burning the reverse of |
photosynthesis |
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how does heat flow outward |
1. conduction of particles from hotter to cooler areas 2. radiation from flames and hot surfaces 3. convection of hot, lightweight buoyant gases that rise upward |
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how does heat move inward |
by conduction, decomposing the cellulose and lignin of wood into gases (pyrolysis) that move through cracks to fuel flames at the log surface |
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stages of fire |
1. flaming combustion (trailing) 2. glowing combustion 3. flaming combustion (leading) 4. preheating |
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glowing combustion |
the organic components of wood that are not volatile enough to turn into gases and turn into flames
- embers that glow red for a while |
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why is wind bad with fires |
because flames are low density and without wind go straight up but wind blows them sideways which creates preheating and a fast spread |
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what allows fire to climb from grasses to tree tops |
vegetation of varying heights |
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how fires burn on slopes |
- fire burns rapidly uphill -there is preheat with the slope fires like to travel up hill faster then downhill |
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big fuel fires |
travel fast up hill when the wind is pushing things the wind pushes embers and if the embers are travelled by the wind the fire can travel the speed of the wind |
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sheltered duff moisture code |
- fire hazard code in canada |
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fire hazard in canada |
varies with temperature and recent precipitations |
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Southern California fire |
near las flores canyon in malibu california houses designed to withstand fire remail unharmed others destroyed - in this environment building homes as fire resistant is helpful |
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fire tornados |
when a big fire gets going it can stimulate enough convection so that you get a fire tornado a lot of low vegetation can be as big as small tornados |
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april 20 2000 fire tornado |
straw fueled farmer killed |
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good fire proofed home |
fire resistant materials landscape without providing fuel for fires gravel fire break |
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USA Mexico california border fire comparisons |
mexican has more fires but smaller areas america has fewer but larger areas |
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el niño conditions and fires |
- don't get the wet season so more fires |
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foehn winds |
when the air is up at an altitude over the mountain water vapour condenses and goes down the mountain you get dry warm winds, low humidity dies out vegetation |
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latest in fighting fires |
-planes and helicopters -fire guards -current breakthrough - real time satellite observation of fires |
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spiral of time |
sense of how old the world is
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age of earth |
4.6 billion years old |
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pharozoic represents what fraction of age of earth |
1/9 |
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how many species currently existing |
40-80 million |
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how many species have gone extinct |
99.9% |
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what does the earths climate alternate between |
green house and ice house |
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climate change is a driver for what |
evolution and extinction |
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how much has C02 decreased by |
a factor of 30 |
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what illustrates the law of superposition |
vertical sequence of sedimentary rock layer |
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faunel succession |
older forms of life die out and new forms develop |
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geological time scale |
based on superposition of sedimentary rock layers and the irreversible succession of fossils -numerical ages were measured on igneous rock found in association with fossil bearing sedimentary rock |
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how many mass extinctions have there been |
5 |
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how long ago did multi cellular organisms appear |
700 million |
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background rate of extinction |
reflects the competition of organisms as they evolve, new species appearing and old ones going extinct |
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when was there an explosion of evolution |
during the cambrian |
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since the cambrian what has the background rate of extinction been like |
flat rate - maybe declining |
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2 different extinctions |
1. mass extinction 2. background rate of extinction |
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mass extinction |
- something extraordinary happens like a natural disaster -when these happen the number of families and genus that go extinct can exceed 90 -affects creatures in all realms -have been 5 of them |
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background extinction rate |
not all realms |
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possible causes of mass extinctions |
1. plate tectonics 2. volcanism 3. climate change 4. ocean composition 5. biological 6. extraterrestrial 7. statistical |
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how would plate tectonics cause extinction |
sea floor spreading rates leading to sea level changes |
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how can volcanism lead to extinction |
flood basalts leading to atmospheric composition changes |
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how can climate change lead to extinction |
solar insolation or orbital cycles |
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how can ocean composition lead to extinctions |
1. oxygenation 2. stratification and currents |
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biological reasons for extinction |
disease radical innovation - competition |
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extraterrestrial reasons for extinction |
impacts molecular clouds supernovae novae starbusters flares |
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statistical reasons for extinction |
gamblers ruin |
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what happens when seafloor spreading rates are high |
the greater the volume of volcanic rock causes ocean water to spill out of the ocean basins and over the edge of continents |
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what happens if seafloor spreading slows |
the sea level drops and runs out of shallow seas |
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is the crestatous sea level rising or falling |
falling |
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is the sea level now considered high or low |
low because in a glacial age |
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gamblers ruin |
just being unlucky if something happens to happen to a small population species the species is no longer valid from bad luck |
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examples of gamblers ruin |
- small numbers, drought, volcanic eruptions, these can go against you for a period of time and your species goes sub viable |
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what place has least extinctions |
AFRICA
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1998 quebec power outage |
large power outage caused by the sun |
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where does fusion happen |
layers of the sun |
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what is the temp of the sun |
55 k |
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whats a sun spot minimum |
where ultraviolet activity is subdued |
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coronel mass ejections |
solar storms, solar flares |
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when do sun storms peak |
after the sunspot cycle |
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mass ejection |
earth orbiting in the solar winds constantly solar winds travel by earth 300-400km/s diffused by plasma |
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when does solar wind go faster |
when the sun throws more mass |
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what does the earths magnetic field do |
influences the plasma and protects us from plasma |
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do the magnetic pole and rotational pole coincide ? |
no |
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what are solar winds turned by when they come near the earth |
the magnetic field |
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solar wind effects |
1. particle strikes -solar wind is mostly protons, hydrogen nuclei, these particles have a certain energy that aren't energetic enough to get to the surface of the earth 2. ionosphere disturbance 3. magnetotelluric currents |
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types of particles |
1. solar wind 2. galactic cosmic rays |
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do solar protons get down as far as aircrafts ? |
no |
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the upper atmosphere can be effected by what? |
interaction with solar winds. conductive depending on the layer or bounce off it |
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what becomes difficult when the ionosphere is disturbed |
radio or telecommunication |
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solar wind flowing out by our planet induces what in the ground? |
currents |
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whats the issue with pipelines and solar winds |
issue with corrosion, you can protect the system with a battery attached to a stick in the ground, which makes the current flow in a different direction |
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Galactic cosmic rays |
don't come from our solar system, come from other sources in the galaxy unlike solar winds - heavy -travel at tremendous velocities -do reach the surface of the earth - can penetrate under ground - can affect computers or airplanes |
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Carrington Event Sept 1 1859
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large coronel mass ejection so strong produced aurora all over the planet -cost of event today 2.6 trillion dollars |
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Impactors in our solar system |
1. asteroid belt 2. Edgeworth kuiper belt 3. oort cloud |
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location of asteroid belt |
between mars and jupiter |
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what made the asteroid belt |
a planet should have formed but jupiter formed too fast and its gravity was so strong it kept the planet from forming |
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edgeworth kuiper belt |
still mass in the plane of our solar system it has clumped together has objects that are 2000 km in diameter pluto one of those objects |
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2.5 au 2.8 au |
no asteroids |
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why is there an absence of asteroids at 2.5 to 2.8 au |
juptior and saturn's gravity |
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what has sculpted whats left behind in the asteroid belt |
4.5 billion years of interactions with jupiter |
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Itokawa |
little asteroid much of the asteroid processed through the belt by collisions |
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where do comets come from |
edgeworth kuiper belt |
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what are comets made of |
1/4 rock 1/2 ice 1/4 organic materials |
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why can we see comets |
as they get closer to the sun they heat up and the gases release |
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why are comets tails pushed away from sun |
solar winds |
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oort cloud |
when the solar system was first formed there were lots of smaller bodies, gas giants through most of the solar system formed into a big cloud around the solar system |
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how fast is the oort cloud traveling |
15m/s |
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arizona crater |
50 000 years ago 1 km in diameter 200 km deep |
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crater in quebec |
215 million years old biggest in canada |
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crater in mexico |
biggest young crater on planet 66 million years ago filled with sediment since can't see from surface 1 km deep hole |
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Comet over sask |
2008 visible 85 km up fragmenting during sight of 4 seconds |
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Chelayabinsk |
russian meteor -sound wave strong enough to knock out windows |
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biggest recent natural space hazard |
66 million years ago wiped out dinosaurs off the yakatan peninsula particularly deadly because of the rocks -sulpheric acid |
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where would u ideally put a meteor |
canadian shield because of metamorphic rock |
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tunguska event |
fragment of something entering in the atmosphere no one has ever been able to find a piece of the projectile 20 years to investigate knocked down trees in 30 km radius rare events every 1000 years |
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overall impact hazard |
-biggest uncertainty is knowing how big an asteroid has to be to cause global killing of plants -famine -matters where the impact occurs |
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what are the two avoidable disasters |
impacts and gaseous lakes |
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current approx population |
7.3 billion people |
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whats the scariest figure up to date in this course |
the human population in the last million years |
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trend in growing population |
1810 - hit a billion 1925 - another billion after that the spacing between the years has been decreasing -last century had very extraordinary things happen |
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how often is another billion added to the population |
every 12 years |
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world population growth rate |
1.2% |
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when was the highest population growth rate
|
1960 - got over 2% |
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what is the population growth in enriched parts of the world |
essentially zero , in canada some provinces have negative population growth |
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how does canada keep its population up |
immigration: more than 200 thousand immigrants per year |
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what part of the world has high growth rates |
in poorer countries - africa very high population growth rates |
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what is the best mechanism to hault population growth |
educating woman and modern medicine |
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what happens when a country introduces modern medicine |
death rate plummets, this happened 100-50 years ago |
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MODERN MEDICINE = ? = ? |
MODERN MEDICINE = FALLING DEATH RATE = FALLING BIRTH RATE |
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what makes societies enriched
|
educating women = demographic transitioning |
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why is most population growth in the 4th world |
the death rate still hasn't fallen so the birth rate is still high and many women don't have an opportunity for education |
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how does the degree of organization also effect population growth |
-exploiting resources: when agriculture got going population went up but then started to drop when they had abused the environment by not replacing the soil |
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techonology and what else play a role in population size |
organization |
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what is the current attitudes toward planning for population |
people these days addicted to exponential growth - this can't go on for long -transient phenonmenon in human history - its temporary |
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exhaustible resources |
oil |
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renewable resources |
forest |
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what is the rate at which you can destroy the resource |
maximum exploitation rate |
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whats an example exploitation of renewable resources |
fisheries |
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what is the bell shape called when you exploit a resource |
hubbert curve |
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when did domestic oil production peak in the us |
1970 and now on decline, there was a second bump when they started exploiting alaska |
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hubbert prediction |
- for natural gas production - peak in 1970 - new peak on hubbert peak from new technology |
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oil production of norway |
fits the huberts curve
they don't have in the reservoirs tight oil reservoirs to access -expectation to keep on the decline -without artificial restrictions produce the hubberts curve |
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what age is our society living in |
oil age - time in earth history when we produced and used it as energy |
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what is the length of time of the oil age |
300 - 350 years |
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litres of oil available per person per day |
- 1973 amount was increased - got harder to find and population exponential increasing |
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when did available oil energy start to decrease |
1973 |
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when was the end of crude oil that contributed to the enrichment of our civilization |
1960 |
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when did commercial production of oil start |
1861 |
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what was the richest decade in our age |
1960 |
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how do you stop war |
enrich people |
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what did jimmy carter say about the moral equivalent of war |
noted that the energy crisis was likely to progressivly worsen and could result in a national catastrophe the moral equivalent of war |
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how much sunlight is reflected |
100% 30% by clouds 70% absorbed then reradiated |
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what is the biggest greenhouse gas |
water vapour |
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if we didn't have water vapour what would our planet be like |
frozen |
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whats the residence time of C02 |
hundred of thousands of years |
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residence time of CFC |
50 years |
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CFC |
destroy ozone layer |
