GEOG 1111 Exam Two (Gervais, Ch. 6, 7, 9, 10, 11 & ENSO from Ch. 5 + Lectures) (* = Visual question, *** = math question)
42. What is the Paris Agreement, and what would it affect? Where does the current U.S. government stand re: the Paris Agreement?
- Aims to reduce the emission of gases that contribute to global warming (CO2 missions). - The US has pledged to cut domestic greenhouse gas emissions 26 to 28 Non-binding, brought China & India into discussion, collective goal to keep 21st century warming under 2*C, US pledged to cut domestic greenhouse gas emissions 26-28% by 2025 and commit up to $3 million in aid to impoverished countries by 2020; Trump stated he would withdraw US from agreement by 2020 :(
19. What damage-related scale is used to rate hurricanes? What does a 5 on this scale mean in terms of winds? How strong does the wind in a tropical cyclone have to be before it gets a name?
Saffir-Simpson Hurricane Scale; 5 means 156+mph winds; strong low pressure center with sustained winds between 39-73 mph winds to get a name
46. Which coastline of the U.S. is best known for high cliffs and rocky beaches? Explain with regard to continental movement.
The U.S. West Coast is best known for its Erosional Coastline. It is steep with cliffs, on advancing edge of continental plate. The East Coast is known for sandy, barrier islands. It has a depositional coastline on retreating edge of continental plate (U.S. Guf and East Coast; most extensive example in the world). This makes it a dangerous place in hurricanes and tsunamis.
More about Oceans (Lecture Notes)
Warmest at top, coldest at bottom Saltiest at top Oxygen at top Thermocline: analog to tropopause in atmosphere (e.g., inhibits convection, tends to limit mixing to narrow vertical region near surface)
50. What "secret ingredient" of ocean water, no more than 4% of it, is essential to understanding oceanic convection?
"Salt is to the ocean as water vapor is to the atmosphere." It profoundly affects density, chemical properties, etc. Na, Cl; also Mg, Ca, K, etc. - How salty? 35 parts per thousand, or 35% (kind of like 0-4% for water vapor in atmosphere) - "briny": > 3.5%; "brackish": < 3.5% - Saltiest where evaporation > precipitation; when water evaporates, the salt is left behind - Baltic Sea: < 1? (low evaporation, high freshwater runoff); - Persian Gulf: = 4% (high evaporation, little freshwater runoff) - N. Atlantic getting more acidic
13. *** What's a multiple-vortex tornado? How does this phenomenon explain the complex damage patterns of many tornadoes?
("whirls inside whirls" that are moving) Motion of main vortex, winds of parent vortex, winds of little vortex = added together produces complex damage (wind fields inside them are complicated) - Where forward speed of storm, funnel's winds and suction vortex winds all add together, winds can be significantly stronger than just a few feet away.
14. What's the Enhanced Fujita scale? What does a 5 on this scale mean, in terms of wind speeds and damage to your house? (Fling that cow on the applet!)
***Flying cow on the applet*** - Fujita scale careful examination of tornado damage to provide after-the-fact estimate of winds EF-0 (light damage) to EF-5 (incredible damage/complete destruction).
48. Oceans: what drives the ocean currents at the surface? What direction do the ocean gyres rotate in the Northern Hemisphere?
2 types of ocean currents: 1. Surface ocean currents driven by wind (Horizontal Movement) 2. Deep ocean currents driven by differences in water density, salinity and temperature (Stream like movement) (Both redistribute heat energy across Earth's surface) The largest ocean currents are wind-driven and spin in the same sense as subtropical highs. Just as Coriolis effect deflects winds to the right in the Northern Hemisphere (Clockwise in NH). Ocean surface currents organize into Gyres that are characterized by circulation at the scale of the ocean basin. (Counterclockwise: SH) Warm currents are red and cold are blue.
55. How much of the world's water is freshwater? Is much of the world's freshwater in: lakes? atmosphere? Rivers/streams?
2.8% of the worlds water is freshwater Much of the worlds freshwater is in Glaciers (77%), Groundwater (22%), Lakes and Wetlands (0.609%), Soil (0.179%), Atmosphere (0.036%), and Streams (0.004%) Oceans are not freshwater but but make up 97.2% of all water
1. *What is the weather today? Are there clouds in the sky? If so, what kind of clouds? Is it raining? It is very humid or very dry? Is the pressure unusually high or low? Is the wind strong? What direction (roughly) is the wind from? Are there fronts nearby—if so, what kind of fronts? Is there a risk of tornadoes? Is a hurricane in the Gulf of Mexico? LOOK AROUND!
72*F, Rain, Precipitation 20%, Wind ENE 4 mph, Humidity:
24. What are fronts? What kind of front is associated with thunderstorms? What kind of front is associated with moderate precipitation into cooler air?
A boundary between two dissimilar air masses. Cold front (vigorous lifting) - region where cold air advances on relatively warm air. (associated with thunderstorms) Warm front (passive aggressive rising) - region where warm air advances on and flows over cooler, heavier air. (associated with precipitation)
27. What kind of fronts does a mid-latitude cyclone have connected to it in the "young adult" or "open" stage? Is a mid-latitude cyclone still dangerous in the "occluded" stage? Ask the Fitzgerald! Also: how long does a mid-latitude cyclone "live"?
A mid-latitude cyclone had a Warm front on the east side of the storm's center and Cold front to the west in the "young adult" or "open" stage. Yes. A mid-latitude cyclone is still dangerous in the occluded stage. A mid-latitude cyclone lives for about a week.
11. Can a tornado happen without a thunderstorm? Can a thunderstorm happen without causing a tornado?
A tornado cannot happen without a thunderstorm. A thunderstorm can happen without causing a tornado. the spinning around rain cloud formation. As long as a rotating column of air is in contact with the ground and a cloud, no need.
16. * Tornado forecasting: in relation to a mid-latitude cyclone and its fronts, where is the most risk from tornadoes? Ahead of the warm front? Behind the cold front? Ahead of the cold front? Choose one, and defend your choice.
Ahead of the cold fronts; classic "squall line" because 4 ways to lift air mountains, convection, surface convection and frontal lifting - winds blow counterclockwise around a low; warm moist air going high is unstable; also have vertical wind shear? those winds can be tornado
6. What are the three kinds of thunderstorms? Which type is the most likely to produce violent tornadoes?
Air Mass / Ordinary - Appearance: "Popcorn" in visible satellite image - Vertical Wind Shear: small - Chance of Severe Weather: unlikely Multicell: - Appearance: - MCC: state-sized circular cloud in satellite imagery - Squall Line: line of thunderstorms in radar or satellite images - Vertical Wind Shear: - MCC: Small - Squall line: Moderate - Chance of Severe Weather: - MCC: Likely (non-tornadic high winds) - Squall line: Likely (20% of tornadoes from nonsupercell storms) Supercell: - Appearance: "hook echo" on radar reflectivity image - Vertical Wind Shear: Large - Chance of Severe Weather: Very likely (80% of tornadoes from supercell) Air Mass (Ordinary): majestic-looking, vertical (no vertical wind shear to tilt it over), without tilt - updraft killed by downdraft, short-lived and unlikely to produce severe weather Supercell: low pressure caused by tilted-upward rotation, low "sucks in" more air, accelerating rotation and causing storm to move to right of upper-level winds, in only about 30% of these storms, a tornado forms. large vertical wind shear, very likely to produce severe weather (tornadoes) Multicell: small-to-moderate vertical wind shear - allows storm to grow new cells, likely to produce severe weather; MCC: state-sized circular cloud in satellite imagery "squall line" ahead of cold front, on radar - moderate wind, 20% of tornadoes,
47. What happens to coral in ocean temperatures above about 30°C? Will this be a problem in the future? Is it a problem now?
Although corals thrive in warm, clean, and clear water, above 30*C, they start to die. Rising ocean temperatures may be responsible for 30% of coral reef die off. But could also be: pollution, less clear water, ocean acidification, or a combination of the three. - Ocean habitat for coral could be greatly reduced by circa 2050
35. Who said this, and when did he say it? It is one of the earlier definitive statements about "global warming": "It has been pointed out frequently that mankind now is performing a unique experiment of impressive planetary dimensions by now consuming during a few hundred years all the fossil fuel deposited during millions of years... there is no doubt that an increase of carbon-dioxide content in the atmosphere would lead to an increased absorption of the outgoing infrared radiation from the earth's surface thus causing an increase of the mean temperature of the atmosphere."
Carl-Gustaf Rossby
33. How is climate different from weather? Which one is "mood," and which is "personality," in Dr. Knox's formulation?
Climate: - Long-term atmospheric condition-including extremes that may occur. - Personality - Long view (decades, centuries, millenia, global) - All the spheres (stratosphere, hydrosphere, biosphere, cryosphere, lithosphere), interactions between different spheres, tree rings, pollen records Weather: - Mood; - Mostly troposphere, radars and satellites, here and now
26. How does the weather change right after cold front passes your location? Describe in terms of change in temperature, dew point, wind direction, and precipitation. What cloud type indicates that a warm front is coming?
Cold Front (After Passage) Temperature: Cooler Dew Point: Lower Wind Direction: Westerly Pressure: Rising Clouds: Clearing, some stratocumulus Precipitation: Ending Warm Front (After Passage) Temperature: warmer Dew Point: HIgher Wind Direction: southerly Pressure: steady Clouds: Cumulus Precipitation: ending Clear, thunderstorms are ahead, rain start to end ***Halo associated with ice crystals: Cirrostratus.
9. * Derechos: What are they, and what do they look like on radar? Why are they dangerous?
Damaging straight line windstorms in multicellular thunderstorms (winds up to 150mph) Evaporative cooling in rear causes strong, sinking jet of air Characterized by "Bow Echo" on radar - name from Spanish for "straight," as opposed to spinning winds. Coined in 1888 Life cycle, cross section, example from MI in 1988 (PICTURE) Small tornadoes can form in "bookend vortices" Wind damage across 240 miles of area; anyone outside is at risk
56. What are some different types of drought? Is much of Georgia currently in a drought?
Different Types of Drought: - Meteorological - Agricultural - Hydrological - Socio-Economic Intensity and Impacts: - D0 Abnormally Dry - D1 Moderate Drought - D2 Severe Drought - D3 Extreme Drought - D4 Exceptional Drought - Short-term impacts: < 6 months (agriculture, grasslands) - Long-term impacts: > 6 months (hydrology, ecology) All of Georgia is currently in varying degrees of drought. Athens is currently in a severe drought (D2); this means crop/pasture loss likely, water shortages common, water restrictions imposed; 68.3% of the state (84.4% D2 - D4).
7. *** What meteorological quantity determines the difference between the three types of thunderstorms?
Different thunderstorm types due to amount of Vertical Wind Shear (change of horizontal wind in both speed and direction as you go up due to jet stream, etc.). Air rushes up in updraft and precipitation descends in downdraft. Thunderstorms that develop in this environment are likely to produce a tornado.
36. In 1967, the first numerical modeling study of global warming due to a doubling of carbon dioxide was published. What temperature rise was estimated due to a doubling of CO2? Have subsequent forecasts of global warming changed this estimated warming substantially?
Estimated temperature increase of 2*C; no
28. T/F: Mid-latitude cyclones are surface weather features with no connection to the mid-to-upper troposphere.
False. Jet streams (polar) are located in the troposphere and jet streams bring the cold air down from the North. Can help low o grow and overtime as it occludes doesn't need to grow anymore.
32. What is the approximate return on investment (ROI) on weather forecasting? For every $1 spent, the U.S. economy benefits by about this much: $__. Explain this ROI with reference to Hurricane Dorian and the U.S. response to it.
Get five-fold back, 1 dollar spent is $5 back. Sometimes business's have to close (planes). We did not evacuate Florida due to Dorian. Because how did we know it wouldn't follow computer program prediction? (NWP). -- Would've cost a lot of money for government and would be a huge ordeal to move people up north.
17. Tornado safety: where do you go in a home or building if a tornado threatens?
Go to basement and interior room/hallway; lowest floor; Crouch in bathtub; Cover self w/mattress/sleeping bag
20. * What does a hurricane look like in a satellite image? What are some of its identifiable features?
Gray shrimps, eye, spiral rain bands
12. * Where is the place on Earth that has the most tornadoes? Where is "Killer Tornado Alley" in the U.S.?
Great Plains (central US)
18. What's a tropical cyclone? Where do they typically form? Where is the worst place on Earth for them? What three ingredients are needed for a tropical cyclone to grow?
Hurricane: organized nearly circular system of thunderstorms around a center of very low air pressure originates in the tropics off if the equator, northwest Pacific Ocean. Ingredients: warm, deep ocean waters, thunderstorm seedling (multicell cluster off africa), relatively gentle high-level winds Northwest Pacific Ocean - Hurricane: name given to intense tropical cyclones in Gulf, Atlantic, Caribbean, and Eastern Pacific (General name: Tropical Cyclone) - "Typhoon" in western Pacific, "Cyclone" in Indian Ocean
37. What has already happened due to global climate change? Will global climate change end in 2100?
Increasing global temperatures (esp. at high latitudes), record high temperatures are occurring more often than record low temperatures and the ratio is increasing with time. The stratosphere is cooling whole the troposphere is warming, snow and ice are melting in the Arctic and in mountain glaciers worldwide, sea levels are rising, oceans are acidifying-pH going down as dissolved CO2 levels go up, species are migrating.
52. Soils: about how long does it take nature to produce 1" of topsoil? Are modern agricultural soil practices capable of being sustainable, i.e. the soil loss <= the soil gain?
It takes about 500 years for nature to produce 1" of topsoil. Modern agricultural soil practices are not capable of being sustainable because they have transformed an erosion rate from 1" per 1000 years to 1" per 40 years. The soil loss is > than the soil gain. Therefore, all topsoil will disappear after 500-5000 years of agricultural use and abuse.
More about Ocean Salinity & Convection
Low temperature and high salinity are the primary driving forces of convection. They pull the dense water of the polar regions downward, which drives a worldwide convection engine called thermohaline circulation (thermo - driven by temperature differences; haline - driven by salinity differences). The cold, salty water submerges primarily in the Labrador and Greenland Seas, and then flows southward toward the equator and beyond. Although convection only occurs locally in the polar regions, it propels thermohaline circulation, which spans the globe like a giant conveyor belt. Even the Gulf Stream and its branches are driven by convection and thermohaline circulation. Although wind also influences the transport of water masses, its contribution is significantly less.
45. Which biome that used to cover much of the eastern Great Plains is now more than 99% gone? Which biome is highly productive but is located on relatively infertile, leached soils and isn't very good for conventional farming?
MGr: Midlatitude grasslands; tall grass prairie; already 99% gone in the U.S. due to farming and is now cropland (Flint Hills of Kansas left). ETR: (ITCZ: Warm and Wet) The Tropical Rainforest Biome is highly productive but is located on relatively infertile, leached soils that are poor for conventional farming (thin soils, no organic matter or minerals; periods of excessive rain). - Tropical soils are deeply weathered due to large amounts of rainfall and warm temperatures that enhance chemical weathering. Rainwater leaches nutrients out of reach of plants. As a result, many tropical soils are nutrient poor.
44. What has caused all but the most recent extinction events in Earth's history?
Meteorite / Comet impacts like the one that killed the dinosaurs.
5. Name some of the life- and property-threatening phenomena that occur with thunderstorms.
Microbursts are surface windstorms (up to 150mph gusts) caused by cold sinking air thats been cooled by rain and evaporation. They are very dangerous to airplanes during take off / landing due to headwind / tailwind combo near ground which can result in crashes. (Ex: President. Reagan's close call near D.C., 1983)
4. *Near the Earth's surface, how do the winds blow in relation to the isobars and in relation to high or low pressure? Because of this, which pressure system is related to bad weather: highs or lows?
Near the Earth's surface, winds blow clockwise around NH highs and counterclockwise around NH lows; Close together isobars (lines on map) are indicative of strong winds. Because of this, low pressure systems are related to bad weather.
40. What are some consequences of "global warming" that don't directly involve rising surface temperatures?
Ocean acidification Species migration Rising sea levels Glacier melting More intense Hurricanes
49. * Does ocean water convect? If so, describe the direction of movement. Where does this happen? Compare/contrast with atmospheric convection.
Ocean water convects as temperature and salt affect density. Dense water sinks (cold & salty), less dense rises (warm & less salty), creating global ocean currents. Cooler dense air sinks creating wind as cool air moves in to replace warm. (air moves by wind from high to low pressure) Sun drives convection as it heats ocean & atmosphere, producing wind and ocean currents. Sun heats ocean/atmosphere near equator. Convection as transfer of heat --- circulating flow of air/water resulting from temperature differences Compare/Contrast with atmospheric convection. ^^ The sun heats atmospheric air -- cold air rushes down from poles to find area of lower pressure near the equator (warmer here bc its where sun is hottest)
10. Lightning: What type of cloud does lightning form in? What is thunder? Also: lightning safety: "When thunder roars..."
One or more Cumulonimbus Clouds have vertical development and produce thunderstorms by lifting of warm moist air. That in turn causes: lightning/thunder, heavy precipitation, high winds, tornadoes Thunderstorms self-electrify when ice and water particles rub against each other in updrafts/downdrafts Lightning forms with electrical discharge within cloud, down to ground = lightning Thunder is a sonic shock wave caused when lightning flash-fries the air to 30,000*C "When thunder roars, go indoors" --- see lightning, count in seconds every 5 seconds = 1 mile from bolt
38. Will the planet die in 2030 if we don't do anything to curb global warming? Elaborate with reference to the "1.5°C vs. 2°C" argument.
Planet won't die, it would just be better to take action now.
51. What substance is present in the world's oceans from the top to the deepest trenches? How much of this substance is recycled in the U.S., roughly, in a year?
Plastic is present in the worlds oceans from the top to the deepest trenches. Only about 9% of this substance is recycled in the U.S. roughly each year.
25. What is an occluded front, and how does it form according to your book? What does it look like on a weather map? When and where do you expect to see it on a map?
Sign of a mature cyclone An occluded front forms when a cold air wraps around a cyclone, lifting warm air off the surface. Cold front overtakes the warm front, can result in brief but heavy precipitation. Purple triangles and half circles. Near the end of the midlatitude cyclone life cycle.
21. * In relation to the "eye," where are the strongest winds in a NH hurricane?
The eye wall, up to 200 mph, right hand side
3. The geostrophic wind is caused by a balance of which two forces? Is this wind a good approximation to reality near the Earth's surface? Why or why not? What about in the upper troposphere in a straight jet stream—is it a good approximation there?
The geostrophic wind is caused by a balance of Pressure Gradient and Coriolis Force. - Pressure gradient force drives air from areas of high to low barometric pressure Geostrophic wind is not a good approximation to reality near the Earth's surface because there is no frictional force (mountains add this). Conversely, geostrophic would be a good approximation to reality in the upper troposphere in a straight jet stream.
23. What weather forecasting technique was used to make the forecast for Hurricane Sandy? Was it a good forecast? Could its track have been predicted if Sandy had occurred in 1912 or 1942 instead of 2012? Why or why not?
The weather forecasting technique used to make the forecast for Hurricane Sandy was the Numerical Weather Prediction; L.F. Richardson - actually solving equations. It was an incredibly accurate forecast given more than week in advance. Its track could not have been predicted if Sandy had occurred in 1912 or 1942 instead of 2012 because it would have been a bad forecast due ti technology, and warnings would've been posted too late. Now forecasts are made using computer models, global surveillance, computer programs.
8. * Where are thunderstorms most common in the U.S.? Where are they most common across the world?
Thunderstorms are most common in Florida: As a result of convective uplift of warm and moist air masses that move north from the Gulf of Mexico. Most common across the world: S.A., Africa
31. T/F: the annual budget for the entire U.S. National Weather Service is less than $1 billion, smaller than the annual UGA budget.
True
39. T/F: Fewer than 70% of Americans believe that global warming is caused by human activities.
True
54. T/F: SW Georgia has deep canyons formed because of bad soil conservation practices.
True. Southwest Georgia is famous for its deep canyons carved by erosion due to bad soil conservation practices. Providence Canyon, GA Stats: - About 1-3 ft of topsoil exists in most regions - Increases at very slow rates - Pre-agricultural erosion rate: 1" per 1000 years - Current agricultural erosion rates: 1" per 40 years - All topsoil will disappear after 500-5000 years of agricultural use and abuse
30. T/F: the first-ever numerical weather forecast was made by an ambulance driver, and it was horrible, but that approach (modified some) is used in all of today's weather forecasts.
True; Lewis Fry (L.F.) Richardson True
43. What university is associated with the modern science of ecology and has the world's only school of ecology?
UGA
34. Name three natural climate change mechanisms. Why can't the one that helped cause the ice ages explain the warming of the past 40 years?
Volcanoes, sunspots and orbital cycles, Solar Variability We should be getting colder but nothing explains why rapidly warming
53. Why isn't cotton grown much in central and northeast Georgia these days?
We don't grow much cotton in central / northeast Georgia due to soil depletion. We carved up the soil and washed it away downriver. The natural fertile black topsoils were maybe a foot thick. Our agriculture laid waste to the soils and wiped it out in 100-200 years. We knew better but economic and social conditions drove the mismanagement of soil. Short-term considerations >> Long-term survival of agriculture
15. * What is a "tornado vortex signature"? What is a "hook echo"? What type of active remote sensing allows us to see these features?
What you see on radar that indicates tornado; usually shown in red and green close together; put it all together got vortex going on. Hook echo signature is a near-surface rotation pattern detected on Doppler radar. Shows a hook that is the tornado. Can be good indicator of tornado genesis.
22. Name three ways a tropical cyclone can kill you. Which one of these threats affected eastern Texas after Hurricane Harvey weakened? Which one affected the Florida Panhandle during Hurricane Michael? Which one affected Puerto Rico during Hurricane Maria?
Wind, storm surge, and rainwater floods Rainwater floods Wind wind Harvey - Jan - rains Maria - wind
2. Current Events/Class Discussion/Previous Test Hard Questions True/False: a) T/F: Name a trace gas with a concentration always much less than 1% of the Earth's atmosphere. b) T/F: A tornado hit Dallas, Texas on Sunday, October 20, 2019. c) T/F: If a lightning bolt strikes several miles away, you have plenty of time to take cover before the lightning reaches you. d) T/F: Sleet forms with temperature inversions and goes plink-plink on your gutters. e) T/F: On a clear day, the Earth's atmospheric gases absorb most of the light coming from the Sun. f) T/F: Heat lightning is a special type of lightning with unique properties that occurs only during certain months of summer. g) T/F: A warm frontal passage in Athens can cause warm, moist weather to turn into cold, dry weather in just a few hours. h) T/F: Carbon monoxide increased in concentration in the Earth's atmosphere from about 288 ppm to nearly 410 ppm from 1860 to the present. i) T/F: The theme of this semester in 1111 is LOOK OUT!
a) Argon, Nitrogen, Oxygen is not; Carbon, Chlorofluorocarbon, Nitrous Oxide, Methane are CO2, CH4, CFCs b) True (No one killed / EF-3 on Fujita scale; damage after the fact to rate tornado intensity) c) False; lighting can travel up to 25 miles in seconds; Every 5 seconds = 1 mile; "When thunder roars, go indoors" d) True; sleet is little ice pebbles / hail is a lot bigger happens with temp inversion (unstable air) e) False; it scatters/transmits? most of it f) False; (Heat lightning can occur at anytime, it is just lightning with no sound.) Lighting cooks the air, causes shock and sound waves that propagate; bend toward denser air (colder air; above surface; so bend up) g) False; warm fronts leading edge of warm air - cool and moist then warmer with winds from south (cold front does cool and moist with cold air - leading edge of cold fronts) h) False; carbon dioxide i) False; Look up and then around
29. Weather forecasting (see eLC for Dr. Knox's notes): when did modern weather forecasting really begin? 16th century? 18th century? 20th century?
early 20th century
Pictures
lows and fronts (what kind? what pressure?) - High Pressure Areas: air descends and diverges within high pressure systems where is a place the winds are strong? (lines close together and clockwise so coming from north) rain and thunder - once front passes and once it moves out = cooler and drier
41. What are some options for reducing the impact of global warming? Do you think geoengineering is a good option? What about Business As Usual? Do you support cap and trade or a carbon tax? Why or why not?
reduce plastics; recycle
