What Has Changed Since Climate Talks in Copenhagen?

This year will mark the most important negotiations on climate change since the 15th gathering of the Conference of the Parties to the United Nations Framework Convention on Climate Change talks in Copenhagen in 2009, COP 15.  Those talks ended up with progress on several important fronts, such as getting developed and developing countries to jointly agree on emissions targets for the first time, but were marred by scenes of chaos in the final hours and bitter recriminations among governments.
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The world has changed markedly since 2009, with key developments in science, geopolitical shifts and a new focus on climate change that all put this year’s crunch conference in a far different context from the last one.  As we prepare for COP 21, it’s worth examining some of the most important of these changes and considering how those differences might influence the tenor of the talks and, ultimately, the outcome.

New Knowledge
First is the expansion of our scientific knowledge.  Thanks to ongoing work from thousands of researchers around the world, we now know even more than we did in 2009 about the workings of climate change, its probable future impacts and what we need to do to avoid the most damaging consequences.

That is the good news.  The bad news is that the warnings from leading scientists are growing ever more urgent.
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Emissions Trends
At the same time scientific warnings on the need to make urgent cuts in emissions have intensified, global emissions have continued to rise in most of the intervening years.
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Political, Economic and Social Shifts
The world has moved on politically as well since the Copenhagen talks.  The clearest sign of this came in the joint announcement late last year of commitments on greenhouse gas emissions from the U.S. and China, the world’s two biggest emitters.
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Perceptions and Trends
While many of the developments in the past six years appear to bode well for Paris, there have also developed a number of perceptions that could jeopardize both an agreement and our ability to tackle climate change.

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