What is the difference between an effusive eruption and an explosive eruption?

-Effusive eruption: lava flows out of the volcanoe
-Explosive eruption: explosion that breaks and tears apart magma into pyroclastic debri.

     What are the five categories of eruption?

- describe each category

•  Icelandic: fissure erupion, low viscosity + low volatiles(H2O)
• Hawaiian: Lava fountains and extensive flows from vents and fissures, low viscosity + low volatiles(H2O)
• Strombolian: explosive blasts, Low‐moderate viscosity +moderate H2O
• Vulcanian: Moderate‐sized explosive eruption ‐dense cloud of ashladen gas rises high above peak Moderate‐high visocoty, moderate high H2O
• Plinian: High viscosity, high H2O,  Large explosive eruptions

What does VEI stand for?

   What are the principle volcanic hazards?

       Ash and bombs

       Pyroclastic flow

       Lava flow

       Lahar

       Debris avalanche

  Which volcanic hazards are most deadly?

Ash and Bombs

Pyroclastic flow

Lava flow

What is a lahar?

  What monitoring techniques are used at volcanoes?

seismic monitoring

ground deformation

gas changes

telemetry

What are the components of volcanic hazard mitigation?

Hazard Mapping

Monitoring

Education

Alert System

What are the 4 alert categories for volcanoes?

-normal/green

-advisory/yellow

-watch/orange

-warning red

What is mass wasting (mass movement in your book)?

Masses of debris or bedrock

moving downhill

What is the main driving force behind mass wasting?

What factors control slope stability?

• Steepness of slope
•  Relief (vertical elevation change) = gravity
• Rock type

- material

- structure

• Water:

-Adds weight

-Acts as a lubricant

•  Vegetation

- Roots hold soil together

- Absorb water

• Triggers

What are common triggers for landslides?

Oversteepening

Overloading

 Undercutting

Earthquakes

Removal of vegetation

Why can water both strengthen a slope or make it less stable?

-adds weight

-decreases shear strength

▪ may increase shear

strength in unsaturated

debris

What is quick clay?

marine clay: inherently weak material, Rain or groundwater can dissolve away the

salt leaving clay+water that can easily be

destabilized

What are the main types of mass wasting (classified according to type of movement)?

Flow

Slide -translational +rotational

Fall

What is soil creep?

What are the indicators for soil creep?

tilted fence posts

curved tree trunks

bed rock bent downslope

How is a flow different to a slide?

slide: block bed slides along a slide surface, relatively coherent

flow: moving mass of unconsolidated material

How is a translational slide different to a rotational slide?

rotational slides: move downward and outward on top of curved slip surface

translational slides:masses move down and out by sliding on surface of weakness; faults, joints, clay, etc. 

How is a fall different to a flow or a slide?

Block of bedrock that

breaks off and falls freely

(or bounces) down a cliff

What is the difference between an earthflow, a mud flow and a debris flow?

Earthflow: earth moves as viscous fluid

Mudflow: flowing mix of soil and water, dominated by fine‐grained material

Debris Flow: flowing mix of debris and water, dominated by coarse‐grained material

Where do debris flows commonly occur?

dry climates

volcanoes(called lahars)

after forest fires

Where do debris avalanches commonly occur?

Mt. St. Helens; Shasta; Cotopaxi,

Ecuador

What are the two types of snow avalanche and how do they differ?

Slab Avalanche: breaks off and slides down the slope

Loose Powder avalanche: lots of air mixed with snow

What is subsidence?

-Ground surface moves downward

-Caused by compaction of loose watersaturated sediment

-Can be caused by removal of groundwater or

oil from the subsurface

-Can be catastrophic: sinkholes form when surface collapses into an underground cave

What commonly causes subsidence?

Can be caused by removal of groundwater or

oil from the subsurface

Give an example of an area undergoing subsidence?

How can mass wasting hazards be mitigated (name some different mitigation methods)?

drainage

retaining walls

 anchor bolts

 terracing

 fiber rolls

 re‐vegetation

What is the difference between weather and climate?

Weather:Highly variable conditions in the atmosphere

(hour‐hour, day‐day, season season, year‐year variability)

Climate: Average pattern of weather in a region over long periods of time

(One exceptionally cold or hot season is not viewed as climate variability)

How much of the sun's radiation is absorbed into Earth's climate system? How much is reflected?

70% absorbed

30% Reflected

What are the main components of Earth's atmosphere? What are the three most abundant?

Nitrogen 

Oxygen

Argon 

Carbon Dioxide 

Neon 

Helium

Methane 

Krypton 

Water Vapor

What are the four layers of the atmosphere and how are they defined (i.e. what is the factor that best demarcates the boundaries between them)?

How does atmospheric pressure change with altitude?

When a packet of air rises, does it cool down or heat up? What happens to water vapor as the air rises?

As air rises it expands and

cools.

Cool air can't hold as much

moisture so moisture

condenses as clouds .

When a packet of air drops down, does it cool down or heat up? What is the result of this in terms of water vapor?

As air sinks it contracts and

warms.

Warm air can hold more

moisture so evaporation

dominates

What is meant by adiabatic lapse rate?

What is the dry adiabatic lapse rate (i.e. the value)?

What drives global air circulation?

Hadley cells ‐ warm air rises at equator and sinks at ~ 30oN and S then flows away

-Westerlies ‐ flow towardpoles

-Trade winds ‐ flow toward equator

Cold air flows from the poles (polar easterlies) 

Where westerlies meet polar easterlies = polar front

What is the Coriolis Effect?

Currents in the oceans and atmosphere turn

-moving bodies turn to the right in the northern

hemisphere

-moving bodies turn to the left in the southern

hemisphere

What are the three main convection cells in global air circulation?

Polar Cells

Ferrel Cells

Hadley Cells

What is a jet stream?

Narrow bands of high- velocity 

winds ‐ meandering flow

What mostly drives global ocean circulation?

What drives deep ocean circulation?

What is El Niño?

Describe the lines of evidence for global warming

Global Temperature Rising

Global Sea Level Rising

Glaciers are retreating

Changes in Artic and frozen ground

What methods are used to extend the record of global temperatures (and CO₂) back beyond our record-keeping

What processes can cause global climate change?

-Volcanic eruptions

-Variations in the Earth's orbit ‐ Milankovitch Cycles

- Solar radiation

-Greenhouse gases

Describe the greenhouse effect

-the rays from the sun hits earth

-the rays reflect back towards space

-but the greenhousegases pick up the heat from sunrays

-some of the heat continues to space

-the captured heat now spreads in every direction

-the extra heat keeps the earths temp in balance

-human activity are letting out greenhouse gases from cars and factories

- a lot more heat is captures by the greenhousegases 

-the climate is changing

List the common greenhouse gases in the atmosphere

Water vapor

 Carbon dioxide

 Methane

Nitrous oxide (N2O)

 Ozone

Name some sources of greenhouse gases

Natural:

Volcanoes

Methane

Ice Ages

Anthropogenic:

Burning of Fossil Fuels

Cement Productions

Deforestation

CFCs

What are the main anthropogenic sources of CO₂ ?

Burning of fossil fuels (coal, oil, natural gas)

Cement production

 Deforestation

 CFCs

Describe the relationship between human activities and global climate change

-25% of global energy consumption

- ~5% of global population

U.S. person uses:

-7 times as much energy as a person in China

- 25 times as much energy as a person in India

- twice as much energy as a person in western

Europe

Describe the consequences of global warming

Sea level change

 Ocean acidification

 Ocean circulation

 Destruction of tropical plant diversity

 Desertification of productive crop land

Increased INTENSITY and FREQUENCY of

climatic and weather events:

- Increased drought in some areas

- Increased flooding in some areas

- More hurricanes, typhoons etc