Exam #1

The Primoridal Earth

>4billion years ago • No free oxygen • Very hot temperature • Under constant bombardment-no protective atmosphere • Poisonous chemicals- methane, ammonia, carbon dioxide • Lethal levels of ultraviolet radiation • No life forms (..at least not yet known)

Summary of factors that control Weather patterns long-term and result in Climate

• Latitude: distance from equator (cooler/dryer towards poles) • Wind- velocity, direction, humidity (proximity to warm/cold air masses) • Ocean proximity- humidity and precipitation • Altitude- temperature, snowpack (orographic effect controlling precipitation and temperature • Albedo- reflectivity of ground surface (darker surface absorbs more heats lighter surface reflects more heat)

Water Cycle

• Key points: o Moisture in the air comes primarily from evaporation: > 97% of water is in the oceans, .001% is in the atmosphere • 75% of the Earth is covered with WATER

Planets

- planets have now been studied from outside our own solar system-we can analyze their chemistry and eventually, determine which ones may have the potential for harboring life.

Planet construction zones

- zones of the new planetary formation have been observed, consisting of flattened disks of gas and dust surrounding young stars.. possible site for future planets?

our earth is ____ billion years old

4.5

The first to make a serious scientific study of this pattern was German geologist __________ __________ (1880-1930).

Alfred Wegener

CHEMOSYNTHESIS

The ecosystem around 'black smokers' is based on bacteria that break down the sulfur in the volcanic gasses and use it to produce energy-

BUT in Wegener's time, very _____ believed that the continents could have moved.

few

Wegener also looked at the distribution of certain ________, ________, and ________, which makes much more sense if the continents were joined together at the time these animals were living.

fossils, plants, animals

Swarms of shrimp around deep-sea vents

• Feeding on sulfur-based bacteria

Cyclonic Storms

• Heaviest destruction mainly due to: o Damage from high wind speed o Flooding due to drenching rains and storm surge

Key Concepts:

• Tsunami can have devastating impact a force for rapid, sudden change • Most damaging ones generated by undersea earthquakes • Earthquakes can occur when tectonic plates become 'locked' and then slip suddenly and violently • Travel very fast across oceans ~ 500 mph • Build in height as approach shallower water along coastlines • Indonesian tsunami in 2004 responsible for over 280,000 deaths

Subduction Zone

• What causes the melting? o 1. Increase temperature downward o 2. Boiling hot water o 3. Hot magma rises and heats the continental crust-causing more melting

Basic Elements of Weather

• What drives the water/weather cycle? o Heat (From the sun) o Rising and falling of air masses • Warm air expands and rises • Cold air is denser and cools, and sinks o Evaporation/precipitation

What are the two types of dating?

absolute and relative

Cyanobacteria

blue green algae, single celled photosynthetic bacteria, not a true algae.

It was more commonly thought that the continents are fixed in _________, and that plants and animals distributions could be explained by ancient and now submerged ________ _________ between the continents.

position, land bridges

Mitigation

• Building codes o Formerly based on sustained wind; now being revised to be based on peak wind gusts o Land use planning in coastal areas-better mgt. of marshes • Evacuation o Storm surges and coastal flooding • Barriers (seawalls) o Coastal barriers can work to some degree o Reconstruct beaches after storms

Tohoku Earthquake and Tsunami March 11, 2011

• Magnitude 9.0 (largest on record for Japan) epicenter off coast of Honshu along plate boundary • Occurred at depth of about 32 km, 70 km from coast • Amount of seafloor displacement estimated at 20-25 meters towards ESE, and 7 meters upward, along a 70 km stretch of seafloor o This is huge! • Remember... average rate: 2-3 cm/year -tsunami waves reached heights of over 40 meters~ (130 feet) and extended inland for over 10 km (>6 miles) -Energy released by the earthquake estimated at 9,320 gigatons of TNT, or approx.. 600 million times the energy of the atomic bomb on Hiroshima Japan, at the end of the World -The earthquake moved the entire island of Honshu 2.4 m (8feet) eastward and closer to North America, and shifted the axis of the Earth by as much as 25 cm (10 inches). • A day on Earth is now 1.8 microseconds shorter than before the quake, due to redistribution of Earth's mass. -18,800 dead or missing -6,200 injured -nuclear meltdowns at three reactors in the Fukushima Daiichi • nuclear power plant complex, led to evacuation of hundreds of thousands of residents • reactor exploding at Fukushima nuclear power plant • Cooling system that should protect reactors failed after quake and tsunami, leading to overheating and explosions • Radiation released, long-term implications unclear- recommended evacuation zone around plant was 80 km(50 miles). -The World Bank's estimated economic cost of the tsunami was $235 billion dollars, making it the most expensive natural disaster in world history. -one unique aspect of the disaster was how thoroughly It was documented by live TV news reports as it unfolded -chile's long Pacific coastline, one of the furthest from Japan at~ 17000 km (11,000 miles) distant, was struck by waves 2 meters (6.6 feet) -The tsunami broke icebergs off the Sulzberger Ice Shelf in Antarctica, 13000 Km (8,100 miles) away. The largest iceberg was about the size of New York City. -debris from the tsunami will continue to drift around in the Pacific for many years

Ash Falls

• Rain down like snow • Thick deposits of heavy ash collapse roofs, especially if it rains

Sumatra Tsunami Damage

• This tsunami was catastrophic for humans- 28,000 humans • Waves carry debris o Boats, cars, shredded buildings erode soil and vegetation • Multiple waves o First wave is not largest

Toxic Gas & Steam

• Toxic gases include SO2, CO2, and HCI o Cameroon Africa, 1986 • CO2 (> 10% carbon dioxide is toxic) cloud is bubbled out of crater, poured downslope, and suffocated 1700 people. o Mt. Vesuvius, AD 79, ash flow killed thousands • Toxic gases killed many who were not buried • Steam- gas driven eruption Krakatoa, 1883 energy of 100 million tons of TNT o Blasted ash 80 Km into atmosphere (jets fly at~10km) o 40 meter high Tsunami created o 36,000 killed in low lying areas

The bacteria are then a major food source for a great variety of life forms:

•Clams, tube worms, crabs, shrimp

the universe is _____ billion years old and expanding

14

Age of the universe

Now estimated at 14 billion years (Ga)

Wegener gathered evidence that the continents had once been joined in a single supercontinent _________ until approx. 200 million years ago and that the continents had then broken apart and 'drifted' into their present positions

Pangea

These huge changes in the position of the continents means that the _______ would have been much different for many areas compared to what we see today.

climate

Weather:

conditions (temperature, humidity, rainfall, etc.) at a particular place and time-short-term

Tsunami

not tidal waves, nothing to with tides mostly caused by earthquakes that displace water • also caused by submarine land sides, submarine volcanic eruptions, asteroid impacts caused by subduction zone becoming locked plates stuck and build up stress that has to be released • sudden slip of several meters creates massive earthquakes largest wave in open ocean from sub-sea earthquake 15 meters as waves approach shore, they get shorter steeper and tighter • bays inlets also magnify wave height • broad waves to tall waves arrival determined by wave period (crest to crest) • 30 minutes between waves 3rd or 4th wave commonly highest • How fast does a Tsunami wave move? o Velocity of wave= (gh) • G is gravity • H is water depth o For deep ocean, depth = 4,600 meters • Velocity= 800 km/hr o For shallower water near shore, depth=100 meters

Law of Superposition

unless something dramatic has happened to upset the normal arrangement, rock layers are older at the bottom and get younger as you go upwards in an undisturbed sequence.

Death of Sun

we have now observed what happens when stars like our own sun die- they eject their gaseous layers into space, glow brightly, forming nebulae-no two are alike. o This is what will- eventually- happen to our sun causing the ultimate "Global Change"

Climate:

weather conditions for a region averaged over a long enough period of time to see the overall long-term pattern

Giant Tube Worms:

• Can be 10 feet long • Distant relatives of earthworms • Red 'plume' used to absorb sulfur, oxygen, contain special hemoglobin to extract oxygen from seawater • Fastest growth rate for any marine animals- 4-5 ft in less than 2 years

Ash flows

• Collapse onto volcano flank. • Hot: often >1000 degrees C • Fast: move at > 100 km/hour o Examples: • Mt. Vesuvius, Italy 79 AD Buried Pompeii, killed thousands • Mt. Pinatubo, Philippines, 1991 • Mt. Pelee, Martinique, 1902 In 3 minutes, 25-40 thousand people killed • No immediate warning

Volcanoes-Tectonic settings

• Convergent margins-subduction zones • Divergent margins- spreading ridges and rifts • "Hot spot" volcanoes

Plate Tectonics-Volcanoes

• Crust of the Earth is a dynamic system...tectonic plates are in motion

Hurricane Characteristics

• Cyclonic storms with wind speed > 119 km/per hour (74mph) is technically considered a hurricane • Storm may range from 150-800 km (up to ~500 miles) in diameter/length • "eye of the storm" o wind speeds much slower (15km/hour) o atmospheric pressure lower o dry air may decent into the eye from the top of the storm • average travel velocity across the oceans.... 25 km/per hour • westward across the Atlantic because of the Trade Winds • hurricane path: frequency/intensity o westward migration of storms o highest occurrences in warmest parts of the ocean

Indonesian Earthquake and Tsunami from 2004

• Earthquake magnitude of as high as 9.3- third highest that has ever been recorded • Wave heights of up to 30 meters • Killed 283000 people • Changes that shape the Earth by 1 cm and altered the period of earths rotation

Panspermia

• Life on earth was "seeded" from space • The hypothesis that life on Earth, or at least some of the essential building blocks of life came on Earth via comets and other space debris that reached the earth • Idea dates back to Greek philosophers and was also somewhat popular in the 1700s, 1800s, and into the 1900s • No evidence but IF true, it potentially extends the lifetime for Life in the Universe back many billions of years, and it suggests the potential for life to have more than one, single origin.

Mantle and Magma

• Magma is molten rock o May contain mineral grains and dissolved gas • Volcano- where magma reaches the surface o Lava is magma that flows on the surface • Magma characteristics depend on: o Composition o Temperature 800-1200 degrees C o Presence of water and other gases

Magma and Volcano Types

• Magma type controlled by: o 1. Composition • and all three V's viscosity (resistance to flow) volatiles (gases) volume

Pacific NW subduction Zone:

• Occasional giant earthquakes can generate giant tsunami • Tsunami warnings are possible, many hours in advance • Landslides can cause huge tsunami!

The Big Clue

• The 'jigsaw puzzle' • Fit of the continents

Formation of Hurricanes

• Tropical Latitudes-warm temperatures o Warm seawater (when would you expect the most hurricanes?) o Between latitudes of 5 and 20 degrees (north and south of equator) o Rising warm moist air expands, cools, and releases heat o Warmest part of the hurricane is near the eye (20 degrees C warmer) o Eye pulls available warm and moist air into the system-growing storm/cyclone o As air rises, rotation forms in rising air o Develops into large, spiraling, low-pressure system

Key factor: moisture in the air-HUMIDITY

• Warm air can hold more water • Thus when air cools, it can't hold as much moisture o It dumps it as rain when air is saturated • What is relative humidity? o Percentage of moisture in the air compared to the maximum amount it can hold (depends on temp and pressure) • Relative humidity in % equals: Actual quantity of water per unit of air/ maximum quantity at the same temp X 100 So on a day with 90% relative humidity, the air contains 90% of the water that it could possibly contain

Key Points

• Weather is short-term, climate is long-term overall pattern • Most water (>97%) on earth is in the ocean • Main source of energy that powers weather and climate is the SUN • Warm air is lighter and rises and releases its moisture o Cold air is denser and sinks • Humidity-degree to which the atmosphere is saturated with water • Orographic effect on mountain slopes causes 'rain shadows' • Large-scale circulation patterns- 'Hadley cells'- cause dry air to descend at 30 degrees North and South, forming deserts • Cyclonic storms are intense, rotating low-pressure systems, fueled by warm ocean water • Hurricanes track westward across Atlantic due to trade winds, making east coast of USA vulnerable.

Wegener's Biggest problems

• What force 'drove' the continents? • How could a continent plow through an ocean basin? • Wegener had a pattern but no mechanism.. -for ~50 years, very few geologists took the idea of 'Continental Drift' seriously.. this changed in the 1950s/60s • discovery of seafloor spreading

Oldest Rocks on Earth

• 4.28 billion years old • greenstone' along northeastern coast of Hudson's bay, Canada • probably formed by ancient volcanoes • most very old rocks have been 'recycled' by geologic processes.

ICELAND

Boundary between North American/ Eurasian plates, exposed above sea level by uplift. -Mid-Atlantic ridge is Earth's longest mountain range • 15,000 km Plate boundary interactions cause most major: • Volcanoes • Earthquakes & Tsunamis • Mountain Ranges

One example of Extreme Weather

CYCLONIC STORMS

Overall Impacts

• >1500 people were killed • ~250,000 jobs lost o associated loss of tax revenue to city and state • costs ~$200 billion, estimated o private insurers~40 billion o government~60 billion o individual losses-remainder

What implications does our knowledge of cosmology have for interpreting the history of our Earth?

• Age of the universe • Planets • Planet construction zones • Death of a Sun

Early Earth

• Heavily bombarded by leftover debris from the origin of our solar system • Possibly early oceans formed by~4.3 billion years ago • No blue sky (comes much later with oxygenated atmosphere) • Lots of volcanic activity, earths surface may have been mainly molten • Poorly known-among the oldest rocks are these from northern Canada.

Many observers noticed that the margins of the continents fit together like pieces in a ________ puzzle.

jigsaw

TECTONICS

Earth's crust consists of very large plates, on average (40 miles) Thick -The plates are suspended over a layer of thick liquid rock, The Earth's mantle -Plates are moved by circulation currents in the molten layer, and can contact one another in 3 possible ways... -plate tectonics predicts where the continents will be in the future -many important discoveries made by manned and remote-controlled deep-sea research subs

Stromatolites

mats of cyanobacteria in mounds in shallow bays- provide clues to what the earliest life forms on Earth may have been like.

The presence of dark ______ and dark ______ is inferred by the presumed gravitational effect it has on the other forms of matter in the Universe.

matter, energy

Geothermal hot springs

on the surface of the Earth water at or near boiling temperature • Another setting for "extremophiles'

Wegener's evidence included similar _______ ________ of the same geologic age on formerly adjacent continental edges.

rock types

The geologic time scale

developed over the last -200 years and is based on dating rocks on the basis of their fossil content (=relative dating) and/or on the dates obtained from radioactive elements in the rocks themselves. (=absolute dating) • Different division of the time scale are named for geographic areas where rocks of that age are well-known or were first discussed or for the relative age of the particular time interval.

Wind

• Air pressure: related to weight of the column of air from the ground to the top of the atmosphere o Warm air mass near the ground has lower density than surrounding air-rises to form low pressure regions o Cold air mass high in the atmosphere has higher density than surrounding air-falls to form a high pressure region • Differences in air pressure between high and low pressure systems creates Wind o Wind blows from high to low pressure gradients

Orographic Effect (mountain)

• Air pushed over a mountain. • Rises and cools, drops rain along flanks and peaks of mountain on windward side. • Windward side: goes up, cools down and is dry then on leeward side warms and thus is called the rain shadow effect • Rain shadow effect o the incoming warm and moist air is "pulled" by the prevailing winds towards the top of the mountains where it condenses and precipitates before it crosses the top. The air, without much moisture left, advances behind the mountains creating a dryer side called "rain shadow o The air rises and starts to cool, as it gets to the top some air will start to condense (forming rain at the top) as It passes the top of the mountain it will start to sink and as the air drops it will start to warm creating the "dryness effect" • Moist air rising over the Bitterroot Range cools & moisture condenses into water droplets - clouds. • Left side of Cali is very wet, right side is very dry (Why?)

Pyroclastics- ash+larger particles

• Airborne fragments of hot rock and spattering lava • Erupt suddenly and explosively • Driven by release of pressure on dissolved steam o Mt. St. Helens- 1980-1 cubic km of ash, reached several states to the east o Mt. Mazama Oregon (Crater Lake), 5000 BC; 40+ cubic km o Mt. Pinatubo, Philippines, 1991

Big Bang Theory

• All of the matter and energy in the Universe was initially confined in a very tiny area. An explosion the big bang-occurred approx. 14 billion years ago, which caused the universe to begin expanding. This expansion continues today. • The rate of expansion has been measured with increasing accuracy in recent years- many of the measurements have come from data collected by the Hubble Space Telescope • Knowing the rate of expansion is key to understanding the age of the universe- now estimated at 13.7 billion years.

Basic Elements of Weather (Contd.)

• Along with air masses and humidity, what else determines where we get precipitation (rain or snow)? o Large-scale factors • Orographic effect • Global ocean & atmospheric circulation patterns

Hurricane Katrina

• August 28-30, 2005-New Orleans o General background on Hurricanes & Katrina o What went wrong-why was there so much damage? o What options exist for preventing another Katrina-level disaster? o What larger lessons were learned?

Yeti Crab:

• Blind, fuzzy crab lives 7000 feet down, around volcanic vents in Pacific • Maintains colonies of bacteria on its body, for food, and/or to help deal with toxic chemicals from the vents.

Types of Volcanoes

• Calderas o High peak • Strato-volcanoes o Perfectly symmetrical, higher peak than calderas • Flood lavas o Gentle slope of lava, tend to be very flat • Shield volcanoes o In Hawaii most volcanoes are shield volcanoes, have a gentle slope

New Orleans

• Everything east of the 17th street Canal was flooded • Remember, this are is mostly below sea level • Highest parts, including the French Quarter, were on the old natural levees of the Mississippi River, flooding there was minimal -many destroyed neighborhoods were contaminated by chemicals and sewage -giant pumps along drainage canals lost power and failed -temporary pumps help drain the city back into Lake Pontchartrain... but TOO LATE, after the levees failed. -rescue efforts were difficult; hampered by water, trash, and mold • people stranded on rooftops • houses had to be searched for trapped people or bodies -everything lay under warm water for weeks; household items destroyed by mold, furniture, appliances, clothing, carpets, sheetrock personal belongings -most flooded structures had to be demolished • mold and mountains of moldy trash Lower 9th Ward: • House floated and dropped on cars • FEMA trailers hooked to utilities provided temporary housing • Houses floated onto rocks.

Kuril- Kamchatka and Japan Trenches

• Extends- 2500 KM from the west end of Aleutian island to Japan • Started forming- 80-90 million years ago, where Pacific plate is being subducted under North American, Okhotsk, and Eurasian plates • Max depth- 10,500 meters • Rapid subduction is responsible for volcanoes and deep trenches. Deep sea snail fish living at ~7,000 meters in depth in Kuril Trench • Deepest living fishes yet observed • Feed on small shrimp that scavenge on carcasses setting on bottom - many important discoveries made by manned and remote-controlled deep-sea research subs -dramatic discovery of last ~30 years • complex ecosystems living in deep sea environments 'powered' by hydrothermal energy from undersea volcanic activity

The two most dramatic features associated with this part of the 'ring of fire' are:

• Extremely deep ocean trenches- where the pacific plate is being subducted under the North American & Okhotsk plates • Extensive development of spectacular volcanoes- forming the spine o the Kamchatka Peninsula, and the Kuril Islands

Driving force behind hurricanes- HEAT, HEAT and more HEAT

• Eye pulls available warm and moist air into the system-growing storm/cyclone • Trade winds drive westward track of hurricanes • The availability of warm ocean water plays a major role in determining a hurricanes strength and path • General rule 1- a path across warm water (across the equator) can strengthen a tropical storm/hurricane • General rule 2- a path across cooler waters(northern latitudes) or landfall deprives...

Weather effects on a Global Scale-Hadley Cells

• Hadley Cells o Regions between the equator and 30 degrees N and 30 degrees S o Warm, moist air rises at equator o Dry air falls near 30 degrees N and 30 degrees S-deserts • Deserts: areas of very low precipitation occur at about 30 degrees from the equator

Volcanic Regions of the U.S-Examples

• Hawaii (hot spot) o Damaging lava flows o Landslides (large segments of islands can slide into ocean) • Cascade range-western US (subduction) o Explosive eruptions-large ash falls, ash flows o Mudflows • The Aleutians-SE Alaska (subduction) o Ash eruptions- damaging to aircraft, cars, atmosphere • Yellowstone (hot spots)

Cyclonic Storms

• Intense, powerful low-pressure systems o Rotate counterclockwise in Northern Hemisphere o Rotate clockwise in southern hemisphere • Called: o "hurricanes" in the Atlantic Ocean o "typhoons" in the western Pacific o "cyclones" in the Indian Ocean

Products of volcanoes

• Lava flows: molten magma pours down slope • Pyroclastics: gas-charged magma blasts from vent o Ash falls: drifts down wind, falls like snow • Significant problem for jet aircraft! o Ash flows: heavy ash collapses back onto volcano • Mudflows: ash and other fragments combined with water • Toxic gas and steam: carbon dioxide, sulfur dioxide -very hot) 800-1100 degrees C -flows downhill -predictable -a threat to structures (generally not life threatening) -Defense: cool and solidify the lava with water

Key Points

• March 2011 Japan tsunami triggered by massive 9.0 undersea Earthquake • Strength of quake was enough to change Earth's rotation around axis, island of Honshu was moved 8 feet eastward, closer to N. America • ~19,000 deaths and 235 billion dollars in property destruction • very serious meltdown of 3 reactors at Fukushima Nuclear Plant released radiation into the area • well-documented by news media including live aerial video • tsunami waves did travel across Pacific, reaching Chile next day • Debris and exotic marine life drifted across Pacific to west coast USA • Tsunami can be recognized in ancient history, leave geological evidence.

Plates are moved by circulation currents in the molten layer, and can contact one another in 3 possible ways...

• Mid-ocean ridges: sites of seafloor spreading where new seafloor is created • Trenches: sites where one plate is pulled under another, or 'subducted' • Faults: sites where plates are fractured and slide past each other.

Long-term effect of Eruptions: Climate Change

• Mt. Pinatubo, 1991, dust and SO2 circled the Earth o Particles stayed for 2+ years to cause atmospheric cooling • Scattered 30% of incoming sunlight in some regions • SO2 may enhance ozone depletion o Mt Krakatoa, 1883, reduced global temperatures by ½ degrees C o Long term effect can also be warming due to increased CO2 -eruption of volcano in Iceland in April 2011, spewed enough ash into atmosphere that it disrupted commercial air travel in Europe for weeks. -"Yellowstone supervolcano"- on top of a "hot spot"

Katrina-What Happened?

• New Orleans- at and below sea level • Katrina- category 3 at landfall-winds up to 130 mph o Struck early morning August 29, 2005 o Strongest surge on eastern side of storm struck Lake Ponchartrain directly • Levees and floodwalls failed o Mostly overtopped o Then eroded, homes flooded o Drainage canals overflowed • Breached London Ave. Canal-sandbagged, but too little too late. • Breached concrete- wall levee along drainage canal collapsed outward from canal; brown wall is temporary fix.

Key Concepts!!

• Noted for many centuries that the edges of the continents fit together like a jigsaw puzzle • German Geologist Alfred Weneger put together geological and fossil evidence that the continents have drifted over many millions of years, but his ideas not accepted in his lifetime • Discovery of seafloor spreading-the creation of new seafloor at mid-ocean ridges-provided key evidence for plate tectonics • Earth's crust consists of major plates that move due to convection currents in molten layers deeper down • Plates interact in 3 primary ways 1-spreading centers at mid-ocean ridges; 2-subduction zones at edges of the plates where there are deep trenches; and 3-fractured areas where there are faults.

Deep-Sea hydrothermal volcanic vents

• Occur in very deep ocean trenches, where no sunlight penetrates • Complex ecosystems based on bacteria that use sulfur (not oxygen) -black smokers and deep-sea vents were discovered in 1970s by 'Alvin'—smoke, is actually a combination of iron and sulfur-rich minerals, spewing from volcanic vents • temperature around vents is over 700 degrees F! • 'Alvin' is equipped with an array of cameras and sampling devices

What went wrong??

• People left stranded in New Orleans, insufficient resources for rescue • Many ignored the risk due to their previous experience of weaker hurricanes • Lack of appropriate planning at federal level o Communication failures; inadequate staging of food and medical supplies • Poor coordination between FEMA, State & Local governments • Dredging of channels & erosion of marshes helped surge (marshes act as natural buffer) • Levees not high enough • Deep dredging in Miss. River for deep-sea ships funnels river sediment into Gulf of Mexico o Results in potentially protective beaches not becoming replenished

Why is this a region of such intense geo-activity?

• Rate of subduction is faster than at other plate boundaries: • 8 cm/year at Kamchatka / Kuril arc vs. 2-3cm/year at more typical plate and boundaries- this means more energy in the system and more potential for catastrophic events • pacific plate is 'torn" leading to a zone of structural weakness and instability-position of the tear is marked by the sudden change in direction of the island arcs

What should be done?

• Rebuild the city; raise and strengthen the levees? o Cost of strengthening and raising flood protection system is ~32 billion to 50 billion o Population is ~ 485,000-100,000 dollars per person o New Orleans will always be potentially vulnerable to hurricanes • Relocate individuals whose property was flooded, to areas outside flood plains? (might be cheaper than redoing the levees) • Rebuild only the higher parts of the city along the old natural levees of the Miss. River?

Hot Spot Volcanoes

• Rising "stationary" column of hot mantle • In the ocean, area of relatively thin oceanic crust melts to form basalt magma as pressure decreases o Example: Hawaii • Under a continent, the basalt melts continent to form magma o Example: Yellowstone

Sugar in Space

• Scientists have found simple sugars in the gas around a star 400 light years away. • Suggests basic building blocks for carbon-based life are not unique to our Earth. The history of our Earth is incomprehensibly vast; • 4.6 billion years- 4,600,000,000 -complex life forms have lived on Earth for less than the last one billion years or only the last 20 percent of earths total history of over 4 billion years. -the only life forms we are certain existed during the first 80 percent of Earth's history were very simple one-celled organisms

What did they find??

• Seafloors have long, continuous mid-ocean ridges formed by undersea volcanoes • The magnetic alignment of the rocks alternatives evenly on either side of the mid-ocean ridge, tracking changes in Earth's magnetic field over millions of years • The rocks are youngest right at the ridges, and get evenly older further out from the ridges • The seafloor is like a slow-moving conveyer belt; new seafloor is produced at the mid-ocean ridge, and the older seafloor is pushed away from the ridge evenly on both sides of the ridge -In 1965, Canadian geologist Tuzo Wilson and other scientists combined Wegener's 'Continental Drift' with the discovery of seafloor spreading- PLATE

Magma formation-spreading centers

• Spreading centers/ocean ridges o 1.) convection causes asthenosphere to rise. Most spreading centers are at oceanic ridges (e.g mid-Atlantic ridge) nearly all of the oceanic crust is produced this way. o 2.) plates are rifting apart (diverging) at spreading center. o 3.) as asthenosphere rises, it melts to form basalt magma o 4.) basalt magma erupts onto the ocean floor. • Asthenosphere=thick but not molten material just below the Earth's crust

Key Concepts:

• The 'ring of fire' in pacific ocean in site of many major volcanoes and earthquakes • Relatively rapid rate of subduction of Pacific plate is primary cause of these often catastrophic events • Dramatic volcanoes and volcanic islands and very deep trenches are associated with ring of fire • Recent discoveries exploring the deep ocean show that complex ecosystems thrive in deep-sea hydrothermal vents, including bacteria that use sulfur, giant tube worms, crabs, clams, shrimp, and fishes • Dramatic example of 'extremophiles'-living organisms that thrive in very extreme environments... clues to origins of life on Earth?

Are the deep-sea vents important for understanding the origin and early history of life on Earth?

• The fact that life can survive, and thrive in harsh conditions, with no sunlight under extreme pressure and at very hot temperatures and using chemicals for energy suggests that life could have begun and existed, under the conditions found on the early Earth.. and elsewhere?

Why does air rise and fall?

• The sun heats the ground, which heats the air. • Warm air expands is lighter so it rises. • Warmer air rapidly rises, then cools and moistures it contains condenses to form rain or hail it contains sufficient moisture

The ring of fire

• Very clear pattern of major earthquakes and volcanic eruptions circling around the Pacific Ocean • 75% of worlds active or potentially active volcanoes • 90% of worlds major earthquakes • composed of series of deep trenches and volcanic islands • results from dynamic nature of tectonic plate interactions around the pacific Ocean • The pacific plate is moving NW and being subducted • The north American plate along the arc of the Aleutian Islands and along the SE edge of the Kamchatka Peninsula and the arc of the Kuril Islands where it is being subducted under the smaller Okhotsk plate

Key concepts:

• Volcanoes are associated with both convergent and divergent plate boundaries, and with "hot spots" • Magma is molten material produced by a volcano-on surface, forms lava • Volcanoes may be: calderas, stratovolcanoes, shield volcanoes, flood lavas • Lava, pyroclastics, mudflows, ash, and steam are all possible products from different types of eruptions • Major eruptions that produce large volume of ash can affect long term climate • Recent eruptions have produced enough ash to disrupt air traffic • Yellowstone "supervolcano" may be due for another major eruption!

Forecasting Hurricanes

• Watches and warnings are very practical-hurricanes generally move slowly and give days of notice • BUT: predicting exact path is more difficult Focus evacuation efforts and predict greatest damage in regions that will undergo the highest storm surge, from wind driving water onshore Storm surge highest on East Side of north-moving storm, due to direction of rotation of the storm Focusing in on coastal Louisiana • A vary vulnerable landscape -coastal land loss with 2 meters of sea level rises • all areas in RED will be underwater -coastal land loss with 6 meters of sea level rise

Can we recognize ancient tsunamis?

• Yes-evidence from core samples and historical accounts indicate that a major tsunami struck the same region of Japan in 969 that was hit in 2011- just over 1,000 years ago

Extremophiles

• organisms that survive in very harsh 'extreme' environments: o great depth in the ocean o polar regions, in and around ice o around thermal hot springs o in environments with no available oxygen o in very dry, wet, hot, cold or violent weather conditions

Galaxies and Stars

• which consist of gas and "stellar dust"- only hold a small fraction of the matter in the universe. • Most of the make-up of the universe-96%- is so called Dark Matter and Dark Energy

Louisiana's Coastal Land Loss

• ~1,000,000 acres of land loss • <100 years • rising sea level is one of the factors that have caused loss of about one million acres of Louisiana wetland since 1900. Natural and human induced processes contributing to these losses include subsidence due to groundwater withdrawal and natural sediment compaction, wetland drainage, and levee construction.