As of this Monday, 174 countries had submitted their national climate plans to the UN, in preparation for the Paris climate summit that begins next week. These “Intended Nationally Determined Contributions” (INDCs) show countries are stepping up to take collective action to address climate change. Governments have set out a variety of different approaches, including specifying absolute emissions-reduction targets, setting economy-wide emissions intensity goals, outlining efforts to adapt to the impacts of climate change, and detailing specific actions they plan to take in a range of...