Term
| What are columns and how do they form? |
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Definition
| When lava cools it contracts and fracture into columnar jointing. |
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Term
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Definition
| A mountain built from magmatic eruptions. Volcanoes are caused by tectonic activity and they pose a number of hazards to humans. |
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Term
| Products of volcanic eruption take three forms |
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Definition
1. lava flows- molten rock that moves over the ground
2. pyroclastic debris- fragments blown out of a volcano
3. volcanic gases- vapor and aerosols that exit a volcano |
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Term
| Volcanic eruptions have two styles of eruption |
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Definition
1. they can flow (like Hawaiian volcanoes)
2. they can blow (like the Cascade volcanoes) |
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Term
| Style of eruption depends on VISCOSITY |
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Definition
Lava can be runny or sticky
-Viscosity is how easily a fluid moves |
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Term
| The viscosity of a lava increases with.... |
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Definition
1. decreasing temperature of lava
2. increasing SiO2 concentration of lava
3. Increasing volatile concentration (water, carbon dioxide, etc) of lava
4. Increasing crystal concentration of lava |
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Term
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Definition
| More viscous so they can EXPLODE. Contain more gas. |
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Term
| Magma Composition controls.... |
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Definition
| Magma density, magma temperature, and magma viscosity |
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Term
| Eruptions produce either... |
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Definition
1. mafic lava flows (not to hazardous)
2. volcani-clastic deposits of ash (fine crystals) and pyroclastic debris (fragments blown into the air). (VERY HAZARDOUS) |
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Term
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Definition
| Cinder Cones, Stratovolcanoes, Shield Volcanoes, Caldera |
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Term
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Definition
| the smallest type of volcano consisting of conical piles of tephra made of ejected pea-sized fragments piled up at a single vent. Parícutin is a cinder cone volcano in Mexico close to a lava-covered village of San Juan. Active from 1943-1952, the volcano is unique in the fact that its evolution from birth, growth to 1200 ft, and its extinction was witnessed, observed and studied by human beings. It is one of the seven natural wonders of the World. |
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Term
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Definition
| intermediate size cone shaped volcanoes consisting of alternating layers of lava and pyroclastic debris. Mt. Fuji, Mt. Rainier, Mt. Vesuvius. Mt. St. Helens – Erupted May 18, 1980. Earthquake triggered landslide of unstable slopes and released pressure. Pyroclastic flows from Mt. Vesuvius destroyed Pompeii, killing 20,000 and preserving a record of Roman life within the ash deposit. Plinian eruptions (also known as Vesuvian eruptions), are marked by their similarity to the eruption of Mount Vesuvius in AD 79. The eruption was described in a letter written by Pliny the Younger; it killed his uncle, Pliny the Elder. |
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Term
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Definition
| Broad, slightly domed-shaped (like an inverted shield). Made by lateral flow of low-viscosity (runny) basaltic lava. Hawaiian Islands. |
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Term
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Definition
| A Ginormous volcanic depression formed from massive eruptions which completely empties the magma chamber at depth so that the volcano collapses. Famous examples include the Crater Lake Caldera (Oregon), the Thera caldera (Santorini Greece), and Yellowstone! The “Yellow Stone” of Yellowstone is silicic rich volcanic tuff. Yellowstone – 1,000 times more powerful than Mt. St. Helens. |
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Term
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Definition
| Pyroclastic flows, lahars, ash deposits, tsunamis |
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Term
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Definition
| Avalanche of hot ash that races downslope up to speeds of 50 km per hour incinerating all in their path. Often rides a cushion of superheated air. |
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Term
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Definition
| Mudflows result when ash is moved by water. Like concrete, this material is dense. 1991 Mt Pinatubo lahar deposit (before and after) Eruption killed 6 people, the lahar killed 1500! |
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Term
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Definition
| generated by massive landslides that occur during eruptions of volcanic islands. |
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Term
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Definition
| killed about 10,00 people from the pyroclastic flows, ash deposits and tsunamis. Caused "The Year without a Summer" in 1816. Generated famine in 19th century. |
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Term
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Definition
| thera caldera caused catastrophic destruction throughout the Mediterranean, wiping out the Minoan Empire and generating major tsunamis that destroyed cities in Egypt. |
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Term
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Definition
| killed 36,000 people. . Massive pyroclastic flows spread across Sumatra and Java. Caldera collapse generated tsunamis that hit coastal towns throughout the region. Currently rebuilding itself. |
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Term
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Definition
| buried Pompeii and Herculaneum |
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Term
| Volcanic Explosivity Index (0-8) |
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Definition
| A single number given used to describe the severity of an eruption. The VEI associated with an eruption is dependent on how much volcanic material is thrown out, to what height, and how long the eruption lasts. Mt. St. Helens (4), Pinatubo (5), Tambora (6), Yellowstone (8!) |
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Term
| Warning signs precede most eruptions |
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Definition
1) increased Earthquake activity (related to magma flow).
2) Higher Heat flow from rising magma.
3) Rapid changes in shape – magma inflation
4) Emission increases – changes in gas mix and volume. |
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Term
| Extraterrestrial Volcanism |
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Definition
| Ancient volcanism evident on Moon- Lunar maria (dark "seas") are regions of flood basalts. Olympus Mons- Extinct Martian Volcano- largest in solar system! |
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Term
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Definition
earth-shaking episodes caused by a rapid release of energy.
- Due to tectonic stresses that cause rocks to break.
- Energy moves outward as an expanding sphere of waves
-Common and caused 3.5 million deaths in last 2000 years |
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Term
| Earthquakes linked to Plate Tectonic Boundaries |
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Definition
Shallow – Divergent and transform boundaries.
Intermediate and deep – Convergent boundaries.
Hypocenter (or focus) - The spot within the Earth where earthquake waves originate.
Epicenter – Land surface above the hypocenter. |
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Term
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Definition
occurs primarily due to movement along faults…crustal fractures that move rock
Inflation of a magma chamber.
1. Volcanic eruptions.
2. Giant landslides.
3. Meteorite impacts.
4. Nuclear detonations. |
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Term
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Definition
| The amount of movement along a fault is termed displacement or offset. |
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Term
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Definition
| reveal the amount of offset |
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Term
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Definition
| can be seen in map (plan view)- looking down on the earth's surface. AND faults can be visualized in cross-section view- looking sideways at a vertical slice. |
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Term
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Definition
| block below the fault (not normal) |
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Term
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Definition
| block above the fault (normal) |
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Term
| Vertically Oriented Faults |
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Definition
| as either right or left lateral and call them strike-slip faults (transform plate boundary faults are strike-slip) |
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Term
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Definition
| both dip-slip (down or up slope) and strike-slip motion |
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Term
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Definition
| one of the worst natural disasters in US history. About 3,000 people died and over 80% of San Francisco was destroyed. It was the “shock heard round the world” and it marks the birth of modern earthquake science in the US. |
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Term
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Definition
1. When rocks deform, they store energy and bend
2. When their strength is exceeded, they rupture, releasing the stored energy as seismic waves
3. After rupture, the rocks rebound to their former undeformed state |
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Term
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Definition
| Faults move in jumps: Once movement starts, it quickly stops due to friction.Eventually, stress builds up again causing failure.This behavior is termed stick-slip behavior. Ideally, if the two blocks move at a constant rate, the time between earthquakes (recurrence) and the offset (displacement) is uniform. In reality, jumps are not regularly spaced: Nankaido region of Japan - one of the few regions where observations on offset exist through several earthquake cycles - neither the time nor the slip amount is uniform from earthquake-to-earthquake. This is why EQs are hard to predict! |
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Term
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Definition
Pass through Earth’s interior.
2 types of Body waves: Compressional, or primary (P), waves. Push-pull (compress and expand) motion. Travel through solids, liquids, and gases. Fastest.
Shear, or secondary (S), waves “Shaking" motion. Travel only through solids, not liquids. Slower than P waves. |
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Term
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Definition
travel along earth’s surface (cause most damage).
2 types of surface waves: Love waves –Move back and forth like a writhing snake. Rayleigh waves –Move like ripples on a pond |
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Term
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Definition
| measure wave arrivals and magnitude of motion. |
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Term
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Definition
| indicates distance from the earthquake. The longer the lag, the longer the distance. |
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Term
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Definition
| A travel-time graph plots the distance of each station to the epicenter. Data from 3 stations can pinpoint the epicenter.A circle is drawn around each station with the radius equal to the distance to epicenter. Circles around 3 or more stations will intersect at the epicenter. |
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Term
| What do seismic waves tell us about Earth’s core? |
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Definition
| The presence of an S wave shadow zone (region where s waves are absent) tells us the size of the outer core and that the outer core is molten liquid. S- waves cannot travel through liquids P- waves get refracted (bent) by the liquid outer core. |
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Term
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Definition
| The amount of energy released. |
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Term
| Maximum seismogram motion |
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Definition
| Normalized for distance. Richter is the most well known (there are others) |
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Term
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Definition
scales are logarithmic (Increases of 1 unit = 10 fold increase in ground motion)
Many small EQ’s but few large ones - 3 largest are 1960 Chile (9.5), 1964 Alaska (9.2), and 2004 Sumatra (9.1) |
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Term
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Definition
| Degree of shaking damage. Roman numerals assigned to different levels of damage. II – Felt by a few stationary people. Suspended objects may swing. V – Some dishes and window break. Most people wake up. VII – Most people are frightened and run Outside, plaster cracks, some chimneys topple. IX– Most building are damaged; some collapse. XII– Total Destruction. |
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Term
| Can we predict earthquakes? |
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Definition
They CAN be predicted – long-term (tens to hundreds of years).
(Based on recurrence interval – average time between events)
They CANNOT be predicted - short-term (hours to months). |
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Term
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Definition
| are mapped to assess risk. This information is useful for…Developing building codes, Land-use planning., and Disaster planning. |
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Term
| Earthquakes do have precursors including |
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Definition
| Foreshocks, Ground level changes and, possibly…Water level changes in wells, gases (Rn, He) in wells, and unusual animal behavior. |
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Term
| What are Intraplate Earthquakes? |
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Definition
| Those that occur in the interior of tectonic plates. |
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Term
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Definition
1) Shaking and ground rupture
2) Fires
3) Soil liquefaction
4) Tsunamis
5) Landslides |
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Term
| Severity of shaking and damage depends on |
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Definition
Magnitude (energy) of the earthquake. More = more.
- Distance from the epicenter.
- Intensity and duration of the vibrations.
- The nature of the subsurface material. |
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Term
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Definition
| transmits waves quickly=less damage |
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Term
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Definition
| bounce waves= more damage |
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Term
| Hazards following earthquakes |
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Definition
fire- stoves, candles, power lines, broken gas mains
Earthquakes destroy critical infrastructure - water, sewer, telephone, and electrical lines, & roads leaving firefighters powerless. |
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Term
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Definition
| Water saturated sediments turn into a mobile fluid. Sand volcanoes form and lean will slump and flow. Buildings may founder and topple over intact. |
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Term
| How is a tsunami generated? |
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Definition
| by rupture of a submarine fault (typically along a subduction zone) |
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Term
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Definition
| occur frequently - about 1/yr. 94 destructive tsunamis in the last 100 years. 51,000 victims (not including 12/26/04). Future tsunami disasters are inevitable. Growing human population in low-lying coastal areas. |
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Term
| The Indian Ocean Tsunami (Dec. 26, 2004) |
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Definition
megafault earthquake (M9.1) originated in the trench to the west of N. Sumatra. The earthquake was the largest in 40 years. Offset exceeded 15 m; rupture > 1100 km long.
Killed more people than any tsunami on record. ¼ million killed or missing and presumed dead. 1.7 million people were displaced (as of 6/4/2009). Coasts were full of Christmas tourists. |
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Term
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Definition
Tsunamis race at jetliner speed across the ocean. They may be almost imperceptible in deep water.
Low wave height (amplitude). Long wavelength (frequency). |
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Term
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Definition
As water shallows, waves slow from frictional drag. Waves grow in height, reaching 10-15 m or more.
Landslides and Avalanches follow earthquakes. Shaking causes weak slopes to fail.
Finally, earthquake devastation fuels disease outbreaks especially in undeveloped countries. Food, water, and medicines are scarce. Basic sanitation disabled. Hospitals damaged or destroyed. Health professionals overtaxed. |
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Term
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Definition
| increase in global surface temperatures |
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Term
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Definition
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Term
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Definition
|
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Term
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Definition
| describes the short-term variation in temperature, humidity, atmospheric pressure, wind, etc. in a given region. |
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Term
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Definition
| is a measure of the average of these variables over longer periods of time and over bigger regions. (BIG PICTURE) |
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Term
| What's the atmosphere made of? |
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Definition
21% oxygen, 78% nitrogen, 0.9% argon, plus trace amounts of these greenhouse gases
Greenhouse gases include Carbon dioxide (CO2) 0.0397% (397 ppm), Methane (CH4) 1.79 ppm, Water vapor (H2O) 0.001 to 5% |
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Term
| Global energy balance and the greenhouse effect |
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Definition
| The atmosphere reflects back 25% of the Sun’s energy and absorbs 25%. The remaining 50% reaches the Earth’s surface. As CO2 greenhouse gas builds up in the atmosphere, more heat is trapped, and global warming occurs. |
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Term
| How does global climate change happen? |
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Definition
| The heat source is the sun (solar radiation). Greenhouse gases trap the heat, the heat that reaches Earth is redistributed by atmospheric and oceanic convection cells, warm air/water rises |
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Term
| variables that can cause Earth’s climate to change |
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Definition
| Change in Sun’s intensity, fluctuations in solar radiation, changes in Earth’s Orbit and tilt, changes in volcanic emissions, changes in ocean currents, changes in surface albedo, concentration of greenhouse gases in the atmosphere |
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Term
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Definition
| primarily regulates temperature. Carbon constantly cycles between the atmosphere, the oceans, and rocks by geological and biological processes. |
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Term
| What causes long-term climate changes? |
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Definition
1) Volcanic gases trap heat, promote global warming so periods of profuse volcanism (many smaller oceans).
2) Biological influences. Formation of organic deposits (coal, oil, natural gas) removes CO2.
3) Silicate weathering of mountains during supercontinent formation (when lots of continents collide forming many high standing mountains) |
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Term
| How does silicate weathering engine work? |
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Definition
| H2O and CO2 combine to form a weak carbonic acid (H2CO3). This slightly acidic rain attack fresh rock exposed in mountain belts and dissolves the rock into → ions + soluble bicarbonate which are carried to the oceans in rivers and recombine to form calcium carbonate or limestone rock. In effect, chemical weathering of mountains sucks CO2 out of the atmosphere like a huge vacuum cleaner working over millions of years – this causes global cooling. |
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Term
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Definition
1) Continental sheet glaciers are a result of latitude.They are found in the higher latitudes, near the poles even at the sea level. Example: Greenland
2) Alpine valley glaciers are a result of altitude. They are found in the higher altitudes, at the top of mountains.
Example: Aletsch glacier in the Swiss Alps. |
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Term
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Definition
| Those glaciers formed as a result of Pangea forming! Cenozoic cooling from 45-50 mya to now may be related to formation of the Himalayan mountain chain (when India collided with Asia). Almost certainly Pangea construction produced a silicate weathering engine that sucked up CO2 and transferred it to the oceans as limestone. |
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Term
| Evidence of snowball earth |
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Definition
1) Huge continental scale glacial deposits of 800 – 600 Ma age found in almost every continent.
2) Paleomagnetic studies have confirmed the presence of some of these continental landmasses near the equator during this worldwide glaciation.
3) Renewal of BIF formation (not formed in the previous billion years). BIFs form when oxygen poor oceans become oxygenated again. The oceans probably became anoxic (without oxygen) when earth was covered completely by ice, separating the water from the atmosphere. |
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Term
| How did snowball earth happen? |
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Definition
| 800 my ago a large proportion of continental landmass during a supercontinent (Rodinia) was situated in the tropics. Warm tropical climate increased rate of silicate rock weathering. Also, as Rodinia broke apart, rifting created newer coastlines exposed for weathering. As a result, the atmosphere lost a lot of CO2 and dramatically cooled. Additionally, ice cover caused what is known as the Albedo effect (its whiteness reflects light away from earth instead of absorbing it) creating a positive feedback loop which caused the planet to cool down further and helped the continental sheet glaciers move further towards the equator. |
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Term
| How did the earth warm up again after being covered incomplete ice? |
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Definition
| With everything covered in ice, silicate rock weathering engine (that vacuums up CO2) shutdown. However, plate tectonics and volcanic activity kept going and with each new eruption, more CO2 got pumped into the atmosphere. Due to increased greenhouse effect the ice finally started melting. And once ice started melting, the albedo effect happened in reverse (again positive feedback). |
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Term
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Definition
| the continental glaciers advance towards the tropics from the north and the south poles, but the tropics remain ice free at the sea level. Ice ages are all about growing and shrinking of continental sheet glaciers. |
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Term
| Global warming, how fast how slow? |
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Definition
| Today, with global warming we are seeing the Albedo effect in reverse! As temperature increases, more ice melts, so less sunlight is reflected back so more energy is absorbed. Its positive feedback! And its one reason why scientists have underestimated the rate of global warming over the past 30 years. |
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Term
| Forming different rock types |
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Definition
| Rivers carry bicarbonate ions to the ocean, where they combine with Calcium ions to form calcium carbonate, on the ocean floor, where it becomes limestone. Limestone, or its metamorphic cousin, marble, is rock made primarily of calcium carbonate. These rock types are often formed from the bodies of marine plants and animals, and their shells and skeletons can be preserved as fossils. |
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Term
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Definition
The element Carbon moves through different reservoirs (both living and non-living) at different rates (fast or slow)
Carbon can reside in the Atmosphere, Biomass (plants and animals), soil, and rocks!
Carbon in rocks is often held away from the rest of the carbon cycle for millions of years (they are carbon “sinks”). |
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Term
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Definition
| is visible in the changing seasons. As the large land masses of Northern Hemisphere green in the spring and summer, they draw carbon out of the atmosphere. So atmospheric carbon content pulsates (ebbs and flows) on a yearly cycle. Annual oscillations of CO2 in the atmosphere (measured since 1957) are due to ‘breathing’ of northern hemisphere forests. |
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Term
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Definition
| plants absorb carbon dioxide and sunlight to create fuel—glucose and other sugars—for building plant structures. This process forms the foundation of the fast (biological) carbon cycle. Coal was originally a layer of sediment, rich in organic carbon. The sedimentary layer was eventually buried deep underground, and the heat and pressure transformed it into coal (it’s a metamorphic rock!). |
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Term
| Human Impact on Carbon Cycle |
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Definition
| Burning of fossil fuels. Emissions of carbon dioxide by humanity have been growing since industrial revolution. About half of these emissions are removed by carbon cycle but other half stays in the atmosphere. Carbon stored in trees. |
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Term
| Least Carbon to most carbon |
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Definition
biomass, atmosphere, oceans (dissolved CO2), organic soil/sediment, marine carbonate sediment, carbonate and bicarbonate ions in oceans, organic carbon in sedimentary rocks (coal, oil, gas), and finally, limestone (or marble).
Rocks are the largest reservoirs of carbon. |
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Term
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Definition
| cycling of Carbon between hydrosphere, atmosphere, biosphere, and geosphere is a great example of Earth as a system. |
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Term
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Definition
| if there is no change in CO2 content in atmosphere. if input=output. Balance can be altered if either rate of input or output (withdrawal) or both is changed by a natural or human induced process. |
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Term
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Definition
| causes cooling or warming to occur |
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Term
| Combustion emissions and volcanism |
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Definition
| volcanism both add CO2 to the atmosphere – but combustion today combustion adds a lot more (100-300x more per year!). |
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Term
| Acidification of the oceans |
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Definition
| Some of the Carbon we are adding to the atmosphere ends up in the oceans (warmer water can hold more dissolved CO2). This leads to death of coral reefs. |
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Term
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Definition
The past 1-2 million years has seen dramatic climate variation
Five major glaciations and twenty to thirty minor glaciations separated by interglacials (short warm periods).
At the last glacial maximum (~21,000 years ago), glaciers covered about 30% of Earth. Now they cover ~10%.
During an ice age global sea level dropped by ~100 m (because water is stored on land as ice) and land bridges formed like the Bering Straight which connected Asia to North America. |
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Term
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Definition
| are rivers of ice that carry large gravel and boulders- depositing them as moraines when the ice melts. |
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Term
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Definition
| blanket the older bedrock throughout the Great Lakes region and New York state (Long Island is a glacial moraine deposit). Stranded large boulders carried by glaciers and left behind are erratics (a good one is in Central Park, NY city). |
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Term
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Definition
| scraping and abrasion (like very coarse sand paper). Rock polish, striations, and grooves are all examples of glacial sculpting (Kelley’s Island glacial grooves are world class!) |
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Term
| Solar Insolation and Climate Change (3 factors) |
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Definition
Small changes in the way the Earth orbits around the Sun affects its exposure to sunlight (insolation) including Changes in the degree in which earth orbit around the sun is elliptical, changes in the tilt of Earth's spin axis, changes in the orientation of the spin axis with respect to the Earths orbit.
These 3 factors are collectively called “Orbital forcing” Milankovitch studied these and used them to predict periods of glaciations and warmer interglacials over the past 1-2 million years |
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Term
| Changes in the degree to which Earth’s orbit around the Sun is elliptical (1) |
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Definition
| The shape of the Earth’s orbit keeps changing from more circular to more elliptical and back (called Eccentricity). And the sun is not always at the center. One cycle lasts about 100,000 years. Earth receives less solar radiation when orbit is more eccentric (elliptical) which results in colder climate. |
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Term
| Changes in the tilt of the Earth's spin axis (2) |
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Definition
| Tilt of Earth’s spin axis (Obliquity) varies from 21.5 to 24.5 degrees and back every 41,000 years. High northern latitudes receive less solar radiation when tilt is small |
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Term
| changes in the orientation of the spin axis with respect to the earth’s orbit (Precession). (3) |
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Definition
| The spin axis wobbles like a top. One complete wooble takes 26,000 years. |
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Term
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Definition
| a heavy one (colder) (O18) and a lighter one (warmer) (O16). All kinds of chemical reactions (organic or inorganic) prefer the lighter oxygen atom. For instance, more of the light oxygen gets evaporated from the oceans. |
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Term
| orbital forcing and insolation |
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Definition
| another important means of climate change (that’s not dependent on CO2 in the atmosphere). |
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Term
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Definition
| ancient atmospheric bubbles which preserve an 800,000-year record of temperature and the datable marine record preserves a nearly continuous deposition throughout the last 2 million years. |
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Term
| Anthropogenic climate change |
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Definition
| OR human climate change. Surface temperatures have been increasing. Global warming is a fact. |
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Term
| Global warning and the future means |
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Definition
| there’s more energy in the atmosphere and the oceans and this has resulted in more Atlantic hurricanes overall and more stronger ones as well (from 5 per year to over 15 per year on average). |
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