- First and second laws of thermodynamics
- First law: conservation of energy and matter--energy can neither be created nor destroyed (what happens to it?)
- Second law: Entropy. In any transformation of energy, some gets 'lost' or degraded into a less usable form.
- Water > turbine > electricity > light bulb > heat
- Sun > grass > cow > steak > heat and other waste
- Put another way, for all the order, there is slightly more disorder in the universe
- What happens to all the stuff?
- Humans live in a state 'far from equilibrium'
- Survival requires a 'continuous input of high-quality energy'
- Solar radiation, light and heat, and the greenhouse effect
- Greenhouse gases: carbon dioxide, methane (60 x more efficient at heat trapping than CO2), nitrous oxide (270 times ...), etc.
- Fossil fuels: coal, oil, natural gas
- Keeling curve , CO2 , CO2 & temperature
- Renewables vs non-renewables
- 'Embodied' energy
- e.g., Odum says to double crop yields requires up to a 10-fold increase in inputs
- Argument for a warming planet?
- Humans' role?
- Back to risk ... who gets it?
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