History Review

❖ What is the actual value expected if a cyclone is passing through at a speed of blank ➢ 74 mph is when it is considered a hurricane (otherwise known as a cyclone) ❖ Tsunami runup ➢ Maximum horizontal distance and vertical height a wave reaches ❖ Most volcanoes are near plate boundaries ❖ What happens to the rocks when you have more silica ➢ More silica means thicker substance (i.e. cold honey when silica is high and temps is low; and water when silica is low and temp is high) ❖ Supercell vs single cell tornadoes ➢ Supercells are characterized by having extremely strong wind (69.5-174 mph or 112-280 km/hr) ■ Hail can exceed 2 inches in diameter ■ Structure has an overshooting top formed by the powerful updraft in the mesocyclone ■ Can last for 2-4 hours ➢ Single-cell are short-lived ■ Last 20-30 minutes ■ Called air-mass thunderstorms and form from a single main updraft ■ Isolated nature so they don’t become severe or gain sufficient energy to become very large ➢ Squall line (multicell line) ■ Elongated line of thunderstorms that can be hundreds of kms in length and forms along or ahead of a cold front ■ Has strong downdrafts ahead of the line, with large hail, lightning, and heavy rainfall, and possibly tornadoes ❖ Coriolis effect ❖ Storm surge causes most death in hurricanes ❖ Flooding causes most destruction ❖ Why more hurricanes in atlantic vs pacific ❖ Steepest at headwaters, more erosion (floodplain/rivers) ❖ Flash Floods in headwaters not floodplains ➢ In arid areas ❖ Climate is variable in multitude of time scales ➢ Amount of CO2 100 million years ago is very different from today ■ Much higher ❖ Sea Surface Temperature has to be at least 26C for hurricane formation ➢ So, southern atlantic and southeastern pacific aren’t warm enough to form hurricanes ➢ Related to coriolis effect, no hurricanes form at the equator because there’s 0 effect at the equator

❖ Substantial submarine explosion that causes caldera collapse, & cause wave ❖ Half a flank of a volcano drops into ocean, tsunami is caused ❖ Water vapor is most potent greenhouse gas ❖ Severe thunderstorm ➢ Winds > 93 km per hour ➢ Hailstones > 1.9 cm ➢ OR generates a tornado ➢ Necessary conditions ■ Large changes in vertical wind shear ● Differences in wind speed and direction ● Greater the wind shear, the more severe the storm ❖ Rain bands ➢ Clouds that spiral inward around center ■ Counterclockwise in Northern Hemisphere ➢ Increase in intensity towards the center of the hurricane ❖ Eye vs Eyewall ➢ Eye is very narrow & calm, no clouds ■ Just warm air moving up ■ Diameters range from 3-37 miles ➢ Eyewall ■ Bands of could full of rain ■ Contain the greatest winds and rainfall ■ “Hot towers” can develop within eyewall before storm intensifies ❖ Structure of the sphere ➢ Why does temperature decrease/increase ❖ Erosion occurs on the outside of the bend because velocity is faster (riffle) ➢ Centrifugal force ❖ Great Galveston is the deadliest hurricane Previous Questions & Answers The reduction of the effects of a disaster is termed Mitigation A proposed explanation of a set of measurements or observations that are untested is A hypothesis The number of years that separate two events of the same size is termed the Return period or recurrence interval of the events An organism that lives on or in an organism of another species and benefits by deriving nutrients at the host’s expense is called Parasite

Mark plate boundaries As a tsunami approaches more shallow water, what happens? It slows down Molten rock that lies below the surface is called ____, and once it erupts and flows onto the surface it is called ___ Magma, Lava Put the following lava compositional types in order from lowest to highest viscosity Basalt, andesite, dacite, rhyolite The largest number of tsunami occur in The Pacific Ocean This type of volcano is the largest in size and has a broad, flat shape formed by repeated eruption of fluid, low-viscosity lava that cover large areas and build up over time Shield volcano What type of earthquake motion does not tend to produce a tsunami? Right-lateral strike-slip fault The convergent plate boundaries around the Pacific Ocean where subduction is taking place and forming approximately ⅔ of all active volcanoes is called the Ring of fire ___ is the primary force that controls mass wasting Gravity A mass movement in which a solid block of material comes down a hillside is termed Translational slide As the amount of water present in a mass movement increases, the velocity of the movement: Increases Curved tree trunks are a visible sign of what type of mass movement Creep Material that accumulates at the base of a steep hill or cliff is termed Talus The energy that moves an earthflow or a debris avalanche comes from Gravity The single greatest cause of ground collapse is Overpumping of groundwater Which scale is used to measure the intensity of tornadoes? Enhanced Fujita

True or False: The ocean cover 97% of earth’s surface and contain about 71% of Earth’s water False Put the layers of the atmosphere in order by altitude from closest to Earth’s surface to highest above Earth’s surface Troposphere, Stratosphere, Mesosphere This effect, which is related to the west-to-east spin of the Earth, causes objects on or near the surface to move perpendicular to htat, in a north-south motion, which makes then appear to be deflected counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere Coriolis Effect True or False: Water vapor is a greenhouse gas True Which is more severe, a winter storm watch or a winter storm warning? Winter storm warning The two most abundant gasses that make up the atmosphere are: Nitrogen and Oxygen A cyclonic storm that forms in the western Pacific Ocean is termed a Typhoon The category designation used to describe hurricanes Is based on the maximum wind velocities the storm generates The eye of a hurricane Is located near the center of the storm and can change size The majority of people who die in tropical storms are killed by Flooding The most costly storm in the history of the US was Hurricane Katrina, that hit the Gulf Coast in 2005 True or False: Only one tropical storm can exist in the North Atlantic at one time False Which of the following items does not affect the course of a hurricane moving through the Caribbean and toward the eastern US? The curved shape of the east coast of the US Along a meandering stream, erosion is most likely to occur where? On the outside of the bend An example of a major flood that was the result of human error was The Johnstown, Pennsylvania flood of 1889 Flash Floods can occur most often In mountains and deserts

a. Plates move laterally past each other with horizontal motion 14. The difference between an epidemic and a pandemic is a. An epidemic is a sudden increase in a disease, a pandemic affects many continents and a significant number of people 15. The difference in height of tsunami waves near the shore and the open ocean a. Could be 30-50 times higher 16. The distance to the epicenter of an earthquake is found a. By comparing the arrival times of the S & P waves 17. Earth’s compositional differentiation is key to continents being above sea level a. True 18. The internal structure of the Earth reflects a. All of above (melting and differentiation, effects of the giant impact that formed the moon, plates subducting) 19. The largest earthquake ever recorded by modern seismometers was a. Chile 1960 20. The magnitude of a hazardous event is a. Inversely correlated with its frequency 21. The mantle is partially molten that’s why no S waves travel through it a. False 22. The MOAC was likely responsible for a. C & D 23. The North American plate has which types of plate boundaries a. All 3 types (Ridges, subduction, subduction) 24. The North American plate is solely made of continental crust a. False 25. The seismic danger to LA county comes from a. The San Andreas fault system and other non-strike slip faults like blinds thrusts 26. The tsunami that led to the establishment of the US Tsunami Warning center was a. The 1946 Alaska Earthquake and Tsunami 27. Both the UCLA and UC Berkeley Campus are on the Pacific Plate a. False 28. There can be multiple waves in a tsunami, but waves arriving later have very little energy a. False 29. Below you will see 3 seismograms and the S-P time curve. Measure the S-P times and find the distance from each of the 3 stations. Then answer the questions a. An average of more than 500km away from each station 30. To measure the Richter magnitude on the 3 seismograms in a previous question you would measure the amplitude of a. S waves

31. You are at the beach in Malibu, a tsunami warning is issued, the tsunami is about 100 miles away, how long can you stay at the beach? Assume it’s traveling at 450 mph in the open ocean and 60 mph near the shore. It starts feeling the shore about 10 miles out. a. Less than 20 minutes 32. What does the impact of natural hazards depend on? a. All of the above (frequency of the event, magnitude of the event, climate, land use) 33. What drives plate tectonics? a. Mantle convection 34. What is the approximate S-P arrival time difference a. 10 minutes 35. What is the difference between prediction and forecast? a. Specific date, time, and magnitude of event vs a range of probability for event 36. What kind of faulting is expected at mid-ocean ridges? a. Normal and strike-slip 37. What would you not expect to see at sites where plates are subducting? a. New seafloor 38. When an earthquake happens, strain energy is released. How is it released? a. In the form of seismic waves 39. Which of the following best describes the internal structure of the earth? a. A chocolate covered cherry, it is solid at the core surrounded by a liquid layer, then a solid but plastic layer, then covered in a thin solid, brittle, coating 40. Which of the following is the correct compositional order of the layers of the Earth from inside to the outside a. Inner core, outer core, mantle, crust 41. Which of the following is used to calculate risk? a. All of the above (probability of event, amount of property damage expected, number of deaths possible, amount of damage to roads and bridges) 42. Which of the following statements best explain why events that have caused disasters in the past are now causing catastrophes? a. Human population growth has caused a greater concentration of population in certain areas and puts a greater demand on earth’s resources 43. Which of the following statements is false about P-waves? a. P-waves cause the most damage in an earthquake 44. Which scale would be most applicable worldwide to describe the ground movements associated with an earthquake? a. The moment magnitude scale 45. Which statement best compares natural hazards with natural disasters? a. A natural disaster has caused a significant amount of death and destruction to an area whereas a natural hazard has the potential to cause death and destruction

■ Contains the ozone layer and is above the Earth’s surface ➢ Mesosphere ➢ Thermosphere ❖ Air is the troposphere is hottest because air is heated primarily from the group up because the surface of the Earth absorbs energy and heats up faster than the air does ❖ Almost all weather occurs in the troposphere, and is where clouds are ❖ Tornadoes are usually spawned by severe thunderstorms ➢ 1992-2002, killed 57 ppl/yr ➢ Defined by vortex extending downward from the cloud and touching the ground ➢ Forms where there are large differences in atmospheric pressure over short distances ❖ Tropical Cyclone ➢ Counter clockwise in northern hemisphere, clockwise in southern ➢ A relatively large and long-lasting low-pressure system ➢ Forms over tropical or subtropical ocean ➢ Closed surface wind circulation around a well-defined center ➢ Classified by maximum sustained surface wind speed ■ Tropical depression <39 mph ■ Tropical storm 39-73 mph ■ Hurricane 74mph or greater ● Major hurricane 111 mph or greater (3-5 in Saffir Simpson Scale) ➢ Nor’easter ■ Extratropical cyclone that moves along northward along East Coast US ➢ Hurricane ■ Tropical cyclone in Atlantic and eastern Pacific Oceans ■ Hot towers can develop within eyewall before storm intensifies ➢ Typhoons ■ Tropical cyclones in Pacific Ocean west of International Dateline and north of the equator ➢ Cyclones ■ Tropical cyclones in Indian Ocean ❖ Storm surges cause most deaths in hurricane hazards ❖ Gradient is the slope of the river ➢ Is shown on the longitudinal profile ❖ Steep at high elevations ➢ Headwaters ❖ Decreases as river reaches base level ➢ Lowest elevation of river, ultimately the ocean ➢ Floodplain ■ Flat surface adjacent to channel

❖ Flash Floods ➢ Caused by intense rainfall of short duration over a relatively small area ➢ Common in arid environments with steep slopes or little vegetation and following breaks of dams, levees, and ice jams ➢ Most deaths in cars ➢ ❖ St Francis dam catastrophe ➢ William Mullholland supervised the construction in 1924 on LA aqueduct ➢ Failed catastrophically in 1928, killing 600 people downstream ➢ Constructed on unstable paleo-landslide deposits ❖ Climate refers to characteristic atmosphere conditions over a long period ➢ Years or decades ➢ Pacific Northwest generally has mild temperatures, high humidity, and lost of rain ❖ Weather refers to atmospheric conditions over short period of time ➢ Days or weeks ➢ It may rain in LA ❖ Greenhouse Effect: solar radiation is reflected by the Earth and the atmosphere ➢ Warms the Earth’s surface ❖ Tsunami: caused by sudden vertical displacement of ocean water, thrust or normal fault - 7.5 M or greater\ - Landslide caused tsunami: Lituya Bay Alaska 30.5 million meter of rock fell/ surge 524 m