Assignment #1

Approximately 1/3 of the class completed assignment- some didn’t give their names with their e-mail- some only sent e-mail to one of us- some didn’t include a word document

- there were a few mis-assignments of discoveries (not a big deal as these answers were supposedto be off the top of your head, not researched)

Global Change

Both natural and anthropogenic

Occurs on multiple times scalesdays, seasons, decades, centuries, millennia

Requires a “whole system” approach, e.g. carbon

Understanding global change requires an interdisciplinary approach

Subjects/ Disciplines

Geology Biology/Ecology

Oceanography Geography

Meteorology Anthropology/Political Science

The Earth System is composed of subsystems

Lithosphere (or Geosphere)

Hydrosphere

Atmosphere

Biosphere

Cryosphere

Exosphere

Anthrosphere

And thesesubsystems areextremely variable…

These are just examplesof terrestrial systems;The ocean has similarvariability

Time scales of cyclic and noncyclic change

History of the Earth - 4.6 billion years

Tectonic (Wilson) cycles - 100's of millions of years

Orbital (Milankovic) cycles - 10's to 100,000’s of years

Oceanic cycles - 1000's of years

Solar and meteoric cycles - 10's to 100's of years

El Nino to seasonal cycles - <1 to several years

Diurnal cycles or shorter - ~ 24 hours

Recap.

Understanding global change is understanding howthe earth system functions. This requires -

Information from many disciplines

Consideration of different sub cycles

Consideration of different time scales

Consideration of different landscapes or ecosystem types

Consideration of human interactions with all of the above

1995 1997

Brazilian Rainforest Loss in Two Years