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COURSE LECTURE NOTES:

| SCIENCE | MATTER | SOLAR SYSTEM | PLANETS | ATMOSPHERE | WIND and TEMPERATURE | HUMIDITY | WEATHERING | SOIL | SEASONS | MASS WASTING | SEASONS and CLIMATE | WIND WORK | STREAMS | LAND FORMS | GROUND WATER | CAVES/KARST | THE OCEAN | TIDES & ESTUARIES | WAVES | GLACIERS | GLACIAL LANDFORMS | VOLCANOES | VOLCANOES | CHON | PLATE TECHTONICS | EARTHQUAKES | ROCKS | CLIMATE CHANGE |

SEASONS and CLIMATE

I - Spring - about March 21st (Spring Equinox) to about June 20th (Summer Solstice)
II - Summer - about June 20th (Summer Solstice)to about September 20th (Fall Equinox)
III - Fall About September 20th (Fall Equinox) to about December 21st (Winter Solstice)
IV - Winter about December 21st (Winter Solstice) to about March 21st (Spring Equinox)

Seasons Diagram

albedo - % of reflected sunlight
aphelion - Earth's furthest point from the Sun - 3 July
perihelion - Earth's cloesest point to the Sun - 3 January

Ice ages - well known ones

end of Proterozoic
Mississippian Pennsylvanian aka carboniferous
Pleistocene

Envionment/conditions during Pleistocene 1.8 mega years ago to 10 kilo years ago

episodic ice ages
few deserts
lower sea level large mammals - mastodon, mammot, giant ground sloth, cave bear, wooly rhino
"cave man" (Cromagnon - us) over kill - humans killed off all the larger mammels. Large groups were hard to sustain so the population divided into smaller groups 12000 Ya, then we over killed the larger mammels by doing things like driving a herd of bison over a cliff to harvest a few while the rest rotted and were wasted.

Mojave climate during Pleistocene

woodlands and lakes
abundant game - large and small

Results of Little Ice Age - mid 13 to mid 18 hundreds

wetter
change in crop patterns
crop failures
wars - unrest
French revolution

Since the Pleistocene

global warming
increased deserts
droughts - crop failures
shift in crop patterns

Poser - "have we evolved enough to prevent wars, or are we already there?"

Climate Changes since the Pleistocene Age

PLEISTOCENE AGE - 1.8 mya - 10,000 ya (legal date)
Most recent Ice Ages occured.

Characteristics

1. Lower ocean levels due to ice being traped in glaciers
2. More glaciers - Parts of North America and Europe were covered.
3. There were few deserts
4. There were large grasslands
5. There were many very large animals (mammoth, cave bears, etc.)




6. The Mojave and Sahara Deserts had lakes and grasslands. Death Valley was a huge lake.

1. Sea level rose
2. Many estuaries were created.




3. All lage animals went extinct - Humans ate them?
4. Glaciers retreated. Only Anarctica and Greenland have them today.




5. Deserts grew.
6. Humans had migration and culture problems, food became scarce - pueblos were deserted.

1. Deltas will be lost with all nutriants
2. Desert will expand further
3. More of the remaining glaciers will melt.
4. Sea level will rise higher.
5. More geasslands will be lost.
6. Human populations and cultures will be further impacted.

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