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110 Cards in this Set
- Front
- Back
What are the four causes of SEVERE WEATHER?
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1) Atmospheric heating, 2) Coriolis Effect, 3) Global wind patterns, 4) Air Masses/weather fronts
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What influences the motion of air as it moves over the earth?
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Continents, mountains, etc.
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Describe the coriolis effect.
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A moving object in the Northern Hemisphere bends to the right (southbound); a moving object in the Southern Hemisphere bends to the left.
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What is the catch to this?
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A northbound plane flying from the equator will also bend to the right in the northern hemisphere; this is due to faster rotation of the earth at the equator.
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What characterizes the air at the equator?
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It is always hot, is of low density, and therefore rises.
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What happens as this equatorial air rises?
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It expands and cools, setting the stage for cloud formation and rainy conditions. The rising air then "sucks up" air from surface.
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Why is this area called "the doldrums"?
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There is very little wind here, stagnation due to major low pressure.
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What happens as the rising air begins to move away from the equator?
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It cools, becomes denser, and goes downward.
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What must occur to create clear skies and dry conditions?
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Air descends, and as it does so, it compresses and warms.
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What does air do at horse latitudes?
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It "pushes down"; these are areas of high pressure.
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How are convection cells created?
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The air pushed down by high pressure at horse latitudes moves toward the equator, where the process will repeat, creating a circular motion.
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Why do prevailing winds occur?
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On surface of earth at horse latitudes, the air is always moving towards the equator.
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Why is there no wind in the doldrums?
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Because the air/wind moves up only, due to low pressure.
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Where is nearly every desert on earth located?
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In the horse latitudes.
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what are the air mass types?
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cP (continental-polar air, cold/dry); cT (cont.-tropical air, hot, dry); mP (marine-polar, wet and cold); mT (marine-tropical, hot and wet).
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What is the most dangerous of all wind types?
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mT. This is the fuel for hurricanes.
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What is one additional type of air (describe)?
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Jetsream--an air mass that occurs in high atmosphere. It has speeds greater than 300 mph and is composed of COLD, DRY air.
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What air type is a Nor'easter?
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mP
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What is produced when these air types meet?
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Fronts.
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What are the types of fronts?
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Cold fronts, warm fronts, and occluded fronts.
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How are cold fronts characterized on maps?
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As having "teeth."
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How does a cold front work?
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The steep, dense air mass moves along the earth's surface and "pushes up" warm air.
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What type of cloud forms from this, and why?
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Cumulus cloud, because warm air is forced up in vertical motion.
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Describe the storms this causes.
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Storms produce a lot of rain but are short-lived.
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How do warm fronts work?
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The warm, gently sloped air mass moves over cold air, causing broadly overcast skies that last a long time.
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How does an occluded front work?
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A cold front "overtakes" a warm front. Both are moving in the same direction, but the cold front moves faster.
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What kind of cloud does this produce?
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"Both"
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What are the stages of a severe thunderstorm?
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Early: updrafts, cloud building; Mature:water droplets become big, updrafts, downdrafts; Dissipating: downdrafts suck in dry air
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What causes hail?
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Jet stream causes freezing in thunderhead; strong updrafts support ice.
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Where does most hail occur?
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In the midwest/plains states (Oklahoma).
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What are hailstorms composed of?
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Concentric layers, like an onion. This takes place during the mature stage and yo-yos between downdrafts and updrafts.
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What is the nebular hypothesis?
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That solar systems are formed from nebulae.
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Describe the stages of the hypothesis.
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1) Nebula contracts, 2) flattening and rotation, 3) formation of planetary rings, 4) accretion of planetary rings.
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How do the inner rings and outer rings differ?
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Inner rings, rocky/metalic. Outer rings, gaseous.
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What is the difference between Jovian and Terrestrial planets?
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Jovian are large and cold; Terrestrial are small and hot.
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How old is the earth?
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4.6 b.y.
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What is the age of the nebular accretion?
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5 b.y.
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What are the earth's tectonic plates composed of?
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Oceanic and Continental crust; basalt and granite.
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What are the three types of plate boundaries?
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Transform, convergent, and divergent.
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Where is the asthenosphere located?
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Just beneath the mantle, or lithosphere.
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Difference between magma and lava?
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Magma is deep beneath the surface of the earth and under volcanoes; lava is exterior. Lava is de-gased magma.
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Difference between basaltic (mafic) magma and rhyolitic (felsic) magma?
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Mafic is low viscosity. 50% silica. Intrusive rock: gabbro. Extrusive: basalt.
Felsic is high viscosity. 70% silica. Intrusive rock: granite. Extrusive: rhylotie. |
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What are the different types and shapes of volcanoes?
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Scoria: tall and steep basalt, andesitic, Mexico.
Shielf: wide with gradual uprise, basalt, Maunaloa, HI Strato: layered, composed of lava and tephra of average andesite, occurs at sub zones, tall peak, small summit crater, Mt. Vesuvius |
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What event is associated with the Deccan flood basalt?
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K/T extinction.
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What event associated with Siberian flood basalt?
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Permian extinction.
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What are tektites?
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glassy melted rock droplets, created by meteorite collision. Small glassy spheres (less than 1 cm) produced by impact.
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Deformation?
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The change that a rock undergoes in volume or shape.
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Stress?
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The force that produces deformation.
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What are the different types of stress?
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Tension, compression and shear.
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What are the types of deformation?
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Elastic, plastic and brittle.
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What are the two main types of faults?
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Dip-slip and strike-slip faults.
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Describe the movement of these faults.
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Dip-slip: vertical. Strike-slip: horizontal.
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What are the two types of dip-slip faults?
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Normal and reverse (+thrust)
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What are the two types of strike-slip faults?
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Right-lateral and left-lateral.
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What type of stress is associated w/ normal faults?
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Tensional.
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What type stress associated with reverse?
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compressional (same goes for thrust)
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What type stress associated w/ right-left lateral?
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Shear.
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What is base shear?
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When the "soft" base of a building moves in the direction of the earthquake, while the rest of the building moves/collapses in the opposite direction.
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What is resonance?
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When the period motion of the building is in sync with the period motion of the seismic waves.
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What is liquefaction?
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Loose ground material such as wet sediment.
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Diff between surface waves and body waves?
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Surface: L-waves, travel along the surface of the earth only. Body waves: travel through earth.
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Two types of surface waves?
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Rayleigh waves: up and down motion. Love waves: move side to side, cause more damage
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Two types of body waves?
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P-waves are fastest, signal more waves to come. Result in compressional change of volume.
S-waves: change in shape (?), rock changes back (????) |
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Which of all these is fastest, slowest?
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P-waves fastest, L-waves slowest.
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Which of these cause greatest amount of ground shaking?
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L-waves.
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What is earthquake intensity?
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Effects of an earthquake, modified mercali scale.
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What is magnitude?
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Direct measure of earthquake strength.
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What are the types of mass wasting?
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creep, landslides (landslip), flows, topples, falls, slumps
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In what ways are slumps and glides similar?
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both keep surface intact while moving.
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In what way do slides and flows differ?
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Slides leave intact body.
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How mudflows and earthflows similar, different?
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Both saturated with water, but mudflows are in semi-arid environments, and earthflows are in moist environments.
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How is lightning formed within a cloud?
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Updrafts and downdrafts shear past each other, activate protons and electrons, create static electricity.
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Where do negative charges attract positive charges from?
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The ground.
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What is the scale by which tornadoes are measured?
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The Fujita scale.
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What causes the rotation and eventual tornadoization of a thunderhead?
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The titling of the thunderhead by the jetstream.
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What year did the Tri-State Tornado take place?
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1925
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What states were affected in the Tri-State tornado?
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Missouri, Illinois, Indiana.
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How many people were killed?
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689
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What is the avg. diameter of a hurricane?
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350 mi
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Avg diameter of eye of hurricane?
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12 mi
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What is the fuel source of hurricanes?
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mT air from equatorial region.
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Where are all hurricane storms born?
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Between 5 degrees and 20 degrees north and south of equator.
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What is the general path of storms?
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East to west.
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What controls the path of storms?
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Tradewinds and coriolis effect.
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What do storms never do?
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Cross the equator.
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What do hurricanes begin as?
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A series of thunderstorms.
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What characterizes a tropical depression?
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Windspeeds greater than or equal to 25 mph
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How does depression become a tropical storm?
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Sits in the same place, grows, reaches speeds of greater than or equal to 40 mph
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What windspeeds are necessary for hurricane classification?
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Greater than or equal to 74 mph
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What are the categories of hurricane?
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Saphir-Simpson scale, 1 thru 5
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When is the hurricane season?
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From summer to early fall.
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In the northern hemisphere, how do storms behave?
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Rotate counter-clockwise.
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In the southern hemis, how do storms behave?
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Rotate clockwise.
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Why do hurricanes, rotating counter clockwise, seem to defy coriolis effect?
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The sucked-in air (low press system) bends to the right in the storm and causes this rotation.
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What are the three catastrophic effects of hurricane?
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High wind speeds, storm surge, flooding.
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What kind of waters are of the most concern with flooding?
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Channel waters.
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What drives the motion of water?
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Solar radiation.
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How is the velocity of a stream measured?
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In meters per second.
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What does velocity control?
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Erosion and deposition.
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What are the controlling factors of flooding?
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Gradient, size and roughness of channel, discharge of stream.
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How is discharge measured?
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width x depth x velocity
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on snaking rivers, where is the velocity always the highest?
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On the outside of curves.
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What is a drainage basin?
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An area drained by a river and its tributaries.
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What is a divide?
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High area that separates one basin from another.
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What is the base level?
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Level below which a stream can no longer erode.
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What characterizes an upland channel?
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V-shaped, narrow, deep
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What characterizes a lowland channel?
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flat floor, large flood plain, erodes laterally.
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What characterizes upland floods?
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Local, and rapid. They don't affect wide area. Flash floods.
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What characterizes lowland floods?
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Regional, prolonged.
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What is the diagram associated with global warming?
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"hockey stick" diagram.
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