Possible pathways for balancing CO2 emissions and sinks as agreed in Paris COP21

A zero balance between the emissions and capture by the earth sinks of CO2 with a maximum rise of Temperature of 1.5 oC with respect to the pre-industrial period was established by Paris COP21 as the global objective by the end of this century. The accomplishment of this objective is uncertain mostly because it was left to the responsibility of each estate. We have calculated the possible evolution of CO2 emissions along this century and the possible final values of atmospheric CO2 concentrations and temperature under four different scenarios: BAU (Business as usual) with a continuation of the current trends of economic development, energy production and soil uses, and with a year increment of renewable energies of 4%; FF (fossil fuel) with fossil energies representing 90% of total global production and with a year increment of renewable energies of 2.2%; RE-S (renewable-slow) with renewable energies growing 4.4% per year; and RE-F (renewable-fast) renewable energies growing 5% per year. The values of atmospheric CO2 concentrations (ppm) and Temperature (oC) increases would be 684-743 and 3.1-3.3 (BAU), 749-823 and 3.4-3.6 (FC), 633-686 and 2.9-3.1 (RE-S) and 532-563 and 2.5-2.6 (RE-F) respectively. Therefore in none of these scenarios the objectives of the COP21 would be accomplished. This accomplishment would only be possible if the technologies of CO2 capture in the electric power plants would complement the RE-F scenario. Only combining the RE-F scenario with the application of a technology to absorb 80% of the CO2 emissions of the electric power plant, levels of 328-363 ppm and an increase of 1.2-1.4 oC could be achieved, and thus the COP21 objectives could be accomplished