Fossil fuel is a general term for buried combustible geologic deposits of organic materials, formed from decayed plants and animals that have been converted to crude oil, coal,natural gas, or heavy oils by exposure to heat and pressure in the earth's crust over hundreds of millions of years.
Fossil fuels impact Carbon cycle
When humans burn fossil fuels, the stored carbon is released into the atmosphere as carbon dioxide. The carbon is then free to cycle through the Earth and can upset the natural balance of the carbon available, changing the way that processes occur on Earth.
Fossil fuels impact the environment
The burning of fossil fuels produces heat-trapping gases that are the main cause of the ongoing rise in global atmospheric temperatures.