Exam:energy in earth systems

a.) Non-renewable energy is energy, "taken from finite resources that will eventually dwindle, becoming too expensive or too environmentally damaging to retrieve"(1). Nonrenewable energy sources come out of the ground as liquids, gases, and solids. Crude oil (petroleum) is the only commercial nonrenewable fuel that is naturally in liquid form. Natural gas and propane are normally gases, and coal is a solid. The four most common nonrenewable resources are oil and petroleum products, natural gas, coal, and uranium. "Renewable energy is energy generated from natural resources such as sunlight, wind, rain, tides, and geothermal heat,which are naturally replenished".(2) the most common renewable resources are solar, wind, geothermal, water, and biomass(wood,ethanol,bio diesel). Renewable resources are far less commonly used because they are generally more expensive to produce than fossil fuels.(1)
b.) Energy in earth systems exist in forms such as thermal energy is stored as heat, chemical energy is stored as fossil fuels, and mechanical energy as stored by tides. Thermal energy is transferred through earth systems via radiation, convection, and conduction. Fossil fuels originate from plants and animals of the past, they turn into usable fuel by decomposing. Nuclear energy is changes through radioactive decay and humans manipulating it to fit our needs. resource such as wind don't change form. But over all the movement to matter through earths systems is driven by gravity, radioactive decay, and the sun.
c.) The three main way that heat transfers occur on earth are through convection, conduction, and radiation. Convection is the transfer of heat from one molecule to another within a substance. An Example of conduction occurring in nature is a coyote laying down on a warm rock.Convection is the transfer of heat through the movement of a fluid, such as water or air. An natural example of convection is getting hot by laying out in the sun. A natural example of radiation is when you are standing on the sun, the sunlight is absorbed by your face and warms it.
"The energy from the sun that is absorbed by your face is called radiant energy or radiation"(3).








1.) http://tonto.eia.doe.gov/kids/energy.cfm?page=renewable_home, Renewable energy, Eai.gov,(November 23,2009)(2)
2.) http://en.wikipedia.org/wiki/Non-renewable, Nonrenewable energy, Wikipedia, (November 23,2009)(1)
3.) http://www.atmos.uiuc.edu/earths_atmosphere/heat_transfer.html, Heat Transfer, University of Illinois, (November 24,2009)(3)
http://www.aos.wisc.edu/~aalopez/aos101/wk5.html