At a conference in Spain today, UN climate secretary Christina Figueres called on nations to dramatically raise their ambition to meet the carbon reduction targets that science demands. "Two degrees is not enough – we should be thinking of 1.5C. If we are not headed to 1.5 we are in big, big trouble," she said according to the Guardian.

1.5 C is the temperature target most associated with the carbon concentration target of 350 ppm. From our first day of action in October 2009, to the recent months of preparation for this year's "Moving Planet," has been a strong advocate for "1.5 to Stay Alive." We're celebrating today with the over 100 nations that have endorsed 350 and 1.5 — there's a lot of work still to be done, but getting the head of the UN climate process to call attention to the 1.5C target is an important first step.

Of course, we'll be looking for Figueres to mention 350 ppm in her next speech! While temperature targets are the common currency of the UN discussions, most scientists agree that setting a carbon concentration target is the clearest way to calculate the emissions reductions humans need to make in order to slow climate disruption. Temperature targets are easily fudgeable — there's still debate about what concentration of CO2 in the atmosphere leads to what target — which means that it's easier for countries to sign up to a commitment and then not do what's necessary to meet it. We've seen this for years with developed countries supposed commitment to limiting warming to 2C, but failure to take any major steps in that direction.

This week, the UN negotiations will continue with what is referred to as an inter-sessional meeting in Bonn, Germany. Our European Coordinator, Diana Vogtel, will be on the ground in Bonn, meeting with our country allies, talking with fellow advocates about how to strengthen the case for the targets science and justice demand, and plotting with youth from across Europe about how to make "Moving Planet" a day to remember. With Figueres' announcement today, she can be doing some celebrating too!

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