Caption: "This carbon cycle diagram shows the storage and annual exchange of carbon (C) between the Earth's atmosphere, hydrosphere and geosphere in gigatons---or billions of tonnes---of carbon (C) (GtC). Combustion of fossil fuels by people adds about 5.5 GtC of carbon (C) per year to the atmosphere." (Slightly edited.)

Carbon (C) in plants mostly comes from the air---and animals get their carbon (C) from plants.

Features:

1. The image does NOT explicitly show volcanic outgassing which the geologically long-term process for injection carbon dioxide (CO_2) into the Earth's atmosphere.

2. UNDER CONTRUCTION BELOW