even though the carbon content on the earth is constant, why us there a rise in temperature due to carbon dioxide?
Answers
Carbon is an atom and each carbon atom is pretty much identical (ignoring isotopes and radioactive decay). However, the compounds formed when carbon atoms bind with each other and other atoms can have very different properties. There is a big difference between the properties of a diamond, pencil lead, coal, oil, and carbon dioxide. The total number of carbon atoms on earth is relatively constant. The ratios of the different forms of carbon-containing compounds is not.
Oil and coal are forms of carbon that were stored within the earth for millions of years and only reintroduced to the surface over a geological timescale. However, by burning these fossil fuels, we are quickly turning them into carbon dioxide in the atmosphere. The rate at which we are creating carbon dioxide greatly exceeds the rate at which it is turned into less environmentally relevant forms. It takes much longer to make coal and oil than it does to burn them, so the global reserves of fossil fuels go down, and the levels of carbon dioxide in the atmosphere go up.