Last December in Paris, world leaders came together to agree on a set of goals and pathways for decarbonizing the global economy and increasing our capacity to adapt to climate change. It was a landmark achievement, but it was just the beginning. Every country — with the support of cities, the private sector, and citizens — must now move swiftly to fulfill its promises and bring climate change under control.
The need for urgent, concerted action cannot be emphasized enough. Any delay will cause negative consequences to continue to accumulate. This will not only cause tremendous suffering, especially to the world's most vulnerable people; it will reverberate for decades to come, making the key goal of keeping the increase in global temperature below 2 degrees Celsius (relative to pre-industrial levels) increasingly costly.
The rapid progress that is needed will require major reductions in carbon dioxide emissions, achieved through increased investment in the development and expansion of cleaner and more efficient energy. At the same time, efforts to conserve and expand carbon "sinks" — that is, the forests, wetlands, grasslands, mangroves and sea grasses that absorb much of the CO2 being emitted — are crucial.