This diagram (copyright Dr Al Rodger) shows the annual (per year) flow of Carbon in the global systems. GtC means gigatonne of Carbon, measured in the metric way and not the American way. As you can see, Carbon is accumulating in the Atmosphere year by year. Also, note how "land use change" - everything from logging old-growth forest, to intensitive agriculture with petrochemical fertilisers/pesticides/insecticides/fungicides/herbicides (in the case of GMO), peat drainage, wildfire, intentional fire for clearing land, animal husbandry... is easily producing 2 GtC per year. If the Oceans and Biomass start to degrade as Carbon Sinks due to Global Warming, then more Carbon will accumulate in the Atmosphere leading to more Global Warming etc etc.
