Paris climate talks: What's at stake?
From 30 November to 11 December 2015 world leaders and representatives from over 190 countries will be meeting in Paris for the United Nations 21st Conference of the Parties (COP21). The aim is to agree a global legally binding climate treaty.
What's the context?
Accelerating climate change. 2015 is almost certain to take the world over a new threshold of 1C warming above pre-industrial levels, surpassing 2014 as the hottest year ever. While 2C was agreed as the level which must not be breached, and would take the world to dangerous warming, in fact anything above 1.5 will have extremely damaging impacts on humans and ecosystems in many parts of the world. Island nations would be wiped off the map, sub-Saharan African agriculture devastated in many regions.
So what do we need to do to keep our climate safe?
Cut our carbon emissions - as fast as possible, halting deforestation and keeping as much fossil fuel in the ground as we can.
The International Panel on Climate Change has calculated how much CO2 we can emit in total and still have a chance of staying within 1.5C, 2C and 3C. The trouble is that we are running through that budget fast. The diagram on the right shows how many years of current emissions would use up the budgets (and you can take off a year from the figures - it was created in 2014!).
We need to get to net zero emissions, and discussions about 1.5C in particular talk about negative emissions (it is important to remember in this that carbon capture and storage is still an unproven technology!).
Thinking about burning through a fossil fuel budget makes it clear why early action is necessary - slowing the emissions rate by half in one year's time saves much more CO2 than aiming to do so in 15 years' time.
What are countries expecting to agree in Paris?
At the time of writing, 155 countries have put forward national climate plans as their contributions to the Paris deal. The problem is that added up, these allow global emissions to continue growing until 2030.
If the pledges are kept to, they would keep warming to perhaps 3C - universally acknowledged to be way beyond any safe limits. So the idea is to continue meeting and persuade countries to increase their levels of ambition in coming years. But remember that early action is much more effective - and in the meantime, fossil fuel energy infrastructure will be built, locking in future emissions and making cuts harder.