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It’s been a few weeks since the announcement of the “historic” COP21 agreement, wherein a majority of the world settled on goals for mitigating and adapting to climate change. Since then, I’ve been asked by countless family members at holiday gatherings how my experience in Paris was and what I... Read More


December 10, 2015 | 2˚C or 1.5˚C – What’s the Difference?

What's the difference? Life or death for millions of people, if you ask island nations and poor countries.

In the years leading up to COP21 in Paris, poor countries have been pushing for a 1.5˚C warming cap instead of the 2˚C cap that rich countries feel much readier to agree to; however, 2˚C (an already ambitious and possibly unrealistic ambition) is associated with rapid sea level rise of “several meters” in coming decades, according to Jim Hansen and his colleagues in the 2015 paper “Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2˚C global warming is highly dangerous." Storm impacts, food shortages and drought will also be worsened, especially in the world’s most vulnerable areas, by a further increase of a full degree point as compared to today’s temperature levels.

When it comes to the power and symbolism of these international negotiations, this 0.5˚C difference is even more significant. Before the COP began, though hopes were high for global unanimity to confront the climate crisis, the 2 degree cap as part of the agreement seemed almost incontrovertible. As of this second week of talks, however, many of the world's richest countries — and biggest emitters — have pledged to back the reduced warming limit in a final text. The list includes the U.S., France, Germany, the UK, China, India, and to the international community’s surprise, Canada. Not so surprisingly, oil-rich nations such as Saudi Arabia have pushed hard since long before the COP, and continue to do so, to keep the 1.5 degree figure out of the agreement.

The debate is now between what the lesser of two evils is: an ambitious and more realistic 2˚C target that largely ignores the voice and plight of poor and island nations, or an even more ambitious and less realistic 1.5˚C target that acknowledges the importance of disadvantaged countries to combat climate change. According to Michael Northrop of the Rockefeller Brothers Fund (RBF), an agreement that includes a 1.5˚C cap is a “brilliant mechanism” by which to pursue diplomatic unity and may enable other controversies such as loss and damage, and finance, to be negotiated more effectively.

Up until now, many previous COPs, such as Copenhagen and Warsaw, were largely seen as failures; governments were not able to agree to significant or binding deals during the negotiations, and climate change has continued mostly unfettered and unaddressed by the international community since the origin of the UNFCCC. Paris has been different based on the motivation and focus of the French government, which has been crucial to providing effective leadership, streamlining talks and text, and maintaining the negotiation schedule.

Paris has also been different for another reason: pressure from businesses, NGOs, and civil society. RBF is a philanthropic fund that advances social change that contributes to a more just, sustainable, and peaceful world. It is one of many institutions that have pledged to divest from fossil fuels, a movement that pushes governments and businesses to transition to a clean and renewable energy economy. Regardless of the wording of the final text, RBF is an example of one of the major lessons of this COP21 — more than any other COP before it — that the climate crisis be confronted by every aspect of our economy and society, not just our governments. With global attention on Paris, delegates have a responsibility to deliver for the planet and future generations. As many have said before, and many will say again: What happens in Paris is far from the end of an international effort to combat climate change. These negotiations will signal to the world how much more work there is still to be done.


Shana Gallagher is one of Conergy's Future Solar Leaders. Shana is an aspiring marine conservation biologist and climate change activist who attends Tufts University in Boston, Massachussetts.