COURSE LECTURE NOTES:
SCIENCE | MATTER |
SOLAR SYSTEM |
PLANETS | ATMOSPHERE |
WIND and TEMPERATURE |
HUMIDITY | WEATHERING |
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 |
CLIMATE CHANGE |
SEASONS and CLIMATE
Changes in the weather, hot, cold, damp, dry, etc. caused by the 23.5 degree angle between Earth's axis and true North.
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)
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
Envionment/conditions during Pleistocene 1.8 mega years ago to 10 kilo years ago
episodic ice ages
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
change in crop patterns
wars - unrest
Since the Pleistocene
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.
1. Lower ocean levels due to ice being traped in glaciers
Changes after the Pleistocene Age
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
Changes that will occur as a result of golbal warming (more of the same)
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.