Unit 1 overview
- Explain the principle of exponential growth
- Distinguish between renewable and non-renewable resources
- Describe our impact as a species
- Describe the scientific method
Exponential growth and doubling time: The rule of 70 the doubling time for the human population is 70 years. Doubling time (years) = 70/annual growth rate % The population is growth at about 1.21% per year.
Renewable resources: Resource that can be used repeatedly because it is replenished through natural processes as long as it is not used up faster than nature can regrow it
Nonrenewable resources: Those that exist in a fixed amount or stock in the earth's crust. They take millions to billions of years to form through geological processes
Human activities can degrade natural capital. Most developed countries with 17%
of the world population use 70% of the earth's resources. Less developed countires
are about 83% of the world's population but only use 30% of the earth's resources.
If everyone in the world lived like that average american then we will need 5 planet earths.
We do have the ability to change this because the third component of sustainability is people finding solutions to the environmental problems we face.
- Identify a problem
- Find out what is known about the problem (literature search)
- Ask a question to be investigated
- Perform an experiment to answer the question and collect data
- Analyze data (check for patterns) - scientific law (well accepted pattern in data)
- Propose a hypothesis to explain data
- Use hypothesis to make testable predictions
- If hypothesis gets accepted it becomes a scientific theory
- If not, hypothesis will be revised
- Make testable predictions
- Test projections
- It will be either to be revised again or accept the hypothesis
Whenever energy is converted from one form to another in a physical or chemical
change no energy is created or destroyed
What is the first law of thermodynamics
Low quality energy usually takes the form of heat that flows into the enviornment. When energy is changed from one
form to another it always goes from a more
useful to a less useful form.
What is the second Law of Thermodynamics
If I don't use this someone else will. if we have free access we will miss use this.