However, the biggest single source, accounting for about half of the global total, is the most traditional - the burning of wood for heat and cooking in developing countries.

BBC: Renewables can fuel society, say world climate advisers

China produces over 15% of the world's total energy, and much of that comes from the burning of coal.

FORBES: Commentary

While that may be true, the studies investigated the total carbon emissions created in drilling and fracking a well and collecting, processing, and burning the gas.

FORBES: New EIA Report Says Shale Gas Boom Could Go Global