Across
- 2. productivity- Biological productivity is a measure of the amount of plant and animal growth in a defined region and time.
- 6. Aerosols are small suspended particles in a gas. Scientists can detect them in the atmosphere. They range in size from one nanometer (one billionth of a meter) to 100 micrometers (one millionth of a meter).
- 7. sea ice- Arctic sea ice is an integral part of the Arctic Ocean and an important indicator of climate change. During winter’s dark months, sea ice will typically cover the majority of the Arctic Ocean.
- 8. Anthropogenic describes a process or result generated by human beings.
- 9. cycle- Carbon cycle describes the process by which living things absorb carbon from the atmosphere, sediments and soil, or food. To complete the cycle, carbon returns to the atmosphere in the form of carbon dioxide or methane by respiration, combustion or decay.
- 12. Aquifer is water-bearing rock from which water can be pumped.
Down
- 1. emissions- Biogenic emissions are emissions generated by living things.
- 3. dioxide- Carbon dioxide is the gas that accounts for about 84 percent of total U.S. greenhouse gas emissions. In the U.S. the largest source of carbon dioxide (98 percent) emissions is combustion of fossil fuels. Combustion can be from mobile (vehicles) or stationary sources (power plants). As energy use increases, so do carbon dioxide emissions.
- 4. is a configuration of molecules and an elemental building block of all organisms on Earth.
- 5. sea ice- Antarctic sea ice is nearly a geographic opposite of its Arctic counterpart because Antarctica is a landmass covered in ice surrounded by an ocean, and the Arctic is an ocean of sea ice surrounded by land.
- 6. Aquaculture uses a body of water for the cultivation of plants and animals. (Compare to agriculture, which uses land to cultivate plants and animals.) Ponds, lakes, rivers, and the ocean serve as places to breed, rear and harvest aquatic species.
- 10. sequestration- Carbon sequestration is the process of removing carbon from the atmosphere and storing it in a fixed molecule in soil, oceans or plants. An organism or landscape that stores carbon is called a carbon sink. An organism or landscape that emits carbon is called a carbon source. For example, soils contain inorganic carbon (calcium carbonate) and organic carbon (humus) and can be either a source or a sink for atmospheric carbon dioxide, depending on how landscapes are managed. Because large amounts of carbon are stored in soils, small changes to soil can have major impacts on atmospheric carbon dioxide.
- 11. Biofuels are renewable fuels derived from biological materials, such as algae and plants, that can be regenerated. This distinguishes them from fossil fuels, which are considered nonrenewable. Example of biofuels are ethanol, methanol and biodiesel.