1. The Physical Environment An integrated system of four spheres

2. What are the four spheres? Atmosphere –Trophosphere 0-10 miles Virtually all water here Ozone layer here 80-85% of mass of atmosphere –Stratosphere 10-30 miles –Mesosphere 30-50 miles –Thermosphere >50 miles Little known

3. Except for water and ozone, composition is fairly constant up to the thermosphere Density goes down as you go up

4. Lithosphere Geology Crust of earth

5. Hydrosphere Water layer on earth Carries heat, moves it pole-equator and vice versa Influenced by the Coriolis effect

6. Biosphere Layer where life is Deepest ocean - highest mountain tops Next week we’ll look at various biomes (specific divisions of biosphere) Ecology applies here

7. Cycles Between the Spheres Law of Conservation of Energy - matter cannot be created nor destroyed Matter and energy can be transformed into various forms Gas-liquid-solid Biogeochemical cycles

9. Abundances Life is very different from its environment

10. Carbon Cycle Looks complex; but it is all about withdrawals to and additions from atmosphere Withdrawls: –Photosynthesis –6CO2 + 6H20 + energy ---->C6H12O6 + 6O2 –Accumulation into tissues Fossil fuels Shells = limestone

11. Oceanic geological Terrestrial Atmosphere

12. Carbon Cycle Additions: –Cellular respiration –C6H12O6 + 6O2 ---> 6CO2 + 6H2O + energy –Literally exhalation –Combustion Of such fossil fuels Global warming = too much CO2 accumulating in atmosphere

14. Carbon cycles goes through all 4 spheres Atmosphere - CO2 gas Hydrosphere - CO2 gas, also in tissues Now in Biosphere When organisms die now tissues become fossilized; part of lithosphere Fossil fuels burned releases CO2 gas back to atmosphere