This guest post was written by Alex Stark who is reporting from the UN Cimate Talks in Durban, South Africa, as part of the Adopt a Negotiator program and TckTckTck.

Since the opening of COP17 in Durban, the US has insisted that a new legally binding treaty regime will be impossible before 2020, and that the voluntary pledges that countries made last year in Cancun will be enough until then. At a press conference yesterday, head US negotiator Todd Stern said “if we do this right over the course of the next number of years—I mean these commitments all range between now and 2020—we can really lay the foundation for climate arrangements, whether it’s in a new treaty or a new protocol.”

Durban is the first major forum where the 2020 number has cropped up, and it is sneaking its way into comments and proposals from many countries. It has been cited so many times over the past week and a half that it has assumed a kind of normalcy here. But we should raise the alarm every time we hear it cited, because it has far-reaching implications that are not immediately apparent.

David Roberts wrote a fantastic piece on Grist.org today summarizing “the brutal logic of climate change”—that is, explaining why the climate doesn’t care as much about the nice things that countries say at the UNFCCC as what they actually do.

Roberts cites a paper by Dr. Kevin Anderson and Alice Bows, “Beyond ‘dangerous’ climate change: emission scenarios for a new world” released earlier this year. The paper models various emissions scenarios based on different peak years. The model in which emissions peak in the year 2020, as they might under such a legal regime, looks at 18 different scenarios. In 13 of those scenarios, reaching the two degree Celsius target, the number commonly agreed upon as being essential to avoid catastrophic climate impacts, is technically impossible. The remaining scenarios would require something like a 10% reduction per year in emissions. Roberts points out that the only thing has ever caused an emissions reduction greater than 1% per year is, in the words of the Stern Report, “recession or upheaval”—not very appealing options.

Most NGOs have been pushing for an emissions peak in 2015, saying that pushing it off until later significantly raises the chances of warming above 2 degrees Celsius, and therefore cataclysmic and irreversible climate change. With a 2020 peak, we’re more likely to see a 3 or even 4 degree rather than a 2 degree world. That doesn’t sound like much of a difference, but the potential on-the-ground impacts are be astonishing.

According to Andrews and Bows, “a 4 degrees C future is incompatible with an organized global community, is likely to be beyond ‘adaptation’, is devastating to the majority of ecosystems, and has a high probability of not being stable.”

es, you read “incompatible with an organized global community” correctly—it’s not hyperbolic to say that 4 degrees of warming could very well spell the end of civilization as we know it.

This afternoon, I had the chance to explain this model to a senior US official, and asked, off-the-record, whether it is really responsible to delay increasing mitigation targets given such potential impacts. Rather candidly, said official admitted that it is not at all clear whether current targets will be enough to keep the world below 2 degrees of warming, but that the pledges made in Cancun were “as far as we could go.”

That may be so, but it’s still not good enough to protect our future.

(Source: www.treehugger.com )