Climate ChangeChanges in water distribution

Changes in Weather Patterns

Extremes

Sahara

Dust Bowl1934 - 35

Causes7 years drought

Overworked soil

Extensive rangeuse

Drought

Dust Bowl

Dust Bowl

Civilian Conservation Corps (CCC)

Shelter Belt

Dust Bowl AftermathEmergency Farm Mortgage ActFrazier-Lemke Farm Bankruptcy ActTaylor Grazing ActEmergency Relief Appropriation

ActSoil Conservation ServiceShelter Belt Project

Consequences of Drought

California

Oakland 1991

San Joaquin Delta2006 (Maurer)

Floods in winterDrought in summer

Fall 2007

Spring 2009

Fargo, ND

Fargo, ND & Moorhead, MN

Midwest 1988

Mississippi 1993

Katrina 2005Erosion

Runoff

Mold

Tree loss

Moche

The Weather

$$ Disasters $$

!Kung Sanhxaro

Ancient Floods5600 BC

Ancient FloodsVishnu

Gilgamesh

Target: Earth

Extraterrestrial Impact

Evidence

Our Moon

Comet Shoemaker - Levy July 1994

Jupiter’s Moon Ganymede

Terrestrial Impact Sites

The Solar System

Geocentrism

Piazzi 1801

CeresVestaPallasJuno

Asteroid Belt10,000+ objects

All < 500 km

Irregular in shape

AsteroidsFragments

OR

Remnants of early solarSystem?

Earth crossers

Kuiper Belt

Kuiper Belt Objects

Oort Cloud

Comets

Omens

Mark Twain & Halley’s Comet

“I came in with Halley's Comet... It is coming again ... and I expect to go out with it... The Almighty has said, no doubt: 'Now here are these two unaccountable freaks; they came in together, they must go out together.”

Comet Composition

Cometary Orbits

Meteor Showers

Meteor ShowersLyrids Apr 24 Comet

186115/hr

Eta Aquarids May 4 Halley 20/hrDelta Aquarids July 30 ? 20/hrPerseids Aug 12 Comet 1862 60/hrDraconids Oct 9 Giacobini 15/hrOrionids Oct 21 Halley 20/hrLeonids Nov 17 Comet 1866 15/hrGeminids Dec 13 Phaeton 50/hr

Meteor Shower 1833

Meteorites

October 2008 (2008 TC3)Entered Earth’s Atmosphere

2008 TC3

Feb 2009

Tunguska 1908

Tunguska

Force = 40 Megatons

Pressure wave

Lake Cheko?

Impact Craters

KT Event

Luis & Walter Alvarez

Iridium anomaly

Soot

Where did it Hit?<-250 km->

65 million years ago

Shocked Quartz

ChondrulesCarbon + silicates

Meteoric

Microspherules

Microscopic glassdroplets produced by rapid cooling

ApproachAsteroid

VS

Comet

Mass Extinction Event

ImpactImmediate:

10+ earthquaketsunamishockwavefirestorm

200 trillion tons TNT

Nuclear Winter http://www.atomicarchive.com/Movies/Movie6.shtml

Long Term Changes50 year cloud cover

Loss of Photosynthesis

Emergence of Mammals

Permian extinction275 million years ago

Large scale insect and marine event

Pangaea

Methane Hydrate Release?

CH4 trapped in watermatrix (low temp,high pressure)

Lake Nyos 1986

Camerooncaldera

CO2 release

Flaming IceExposure to Oxygen:

flammability

Results

Mass Extinctions

The Next Collision?

Apophis

ApophisApproach:

2029

Return Apr 13, 2036

Impact Trajectory

1950DA2880

B612 FoundationLocate & deflect

Earth crossingasteroids

Rusty Schweikart

Risk

Alternative ExplanationsSupernova?

Megavolcano(es)

Marine Regression

Pathogens

SupernovaProduces Pt-244

2 million years agoFe-60 deposits

MegavolcanoesDeccan Traps

60-68 x 106 years ago

Shiva Crater

Marine Regression

PathogensT. rex coprolites

Parasite InfectionsSandflies roundworms

Greatest Threat

Triumph of Survival