Coal and oil are made from plants and animals that died millions of years ago when the atmosphere contained abundant carbon dioxide plant food. They are now very concentrated forms of energy which can be extracted from very small areas of land. Burning these natural hydro-carbons returns CO2 and fresh water to the atmosphere thus greatly assisting global plant growth. If we are lucky these extra gases in the atmosphere may also slightly delay the start of Earth’s next cooling cycle, but this looks unlikely.
