Throughout its life, the United Nations has played a pioneering role in the world of ideas. COP21 – also known as Paris 2015 – shows the path for the United Nations to establish a new governance that will enforce the compliance of a new planetary carbon-pricing system. Maintaining global warming below 2 °C means implementing an efficient carbon-pricing system, supported by effective measures promoting a green energy transition. A planetary carbon governance yields a number of new insights that include the following: (1) a bonus-malus system with a fixed signal price for carbon, (2) a planetary carbon market that will gather existing regional carbon markets, (3) a hybrid carbon-pricing system linking a carbon tax and a carbon market for advanced countries and (4) a support mechanism for emerging and developing countries to assist them with a carbon-pricing system. This new governance will promote an energy transition plan. In the COP21 context, responsible policymaking requires key characteristics for the enforcement of a successful planetary carbon-pricing system
carbon market, carbon signal-price, greenhouse gases, international governance, United Nations
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