Negotiations for a climate deal in December are getting down to the wire at the penultimate session in Barcelona this week. Negotiators are hashing through the essential minutiae of an agreement – a process not without tensions – but at moments like this it's important to keep in mind what the final deal should look like.

There is a set of principal building blocks that need to be put in place for the turn toward safety. Our brief, five-page analysis, Turn toward Climate Safety, lays them out and shows how to generate sufficient financing to make it happen.

The goal, in the end, is a firm limit on carbon emissions in all large emitting countries, and a peak in global emissions by 2020.

But don't take it from us.

Yesterday and today, the Financial Times published a terrific analysis of climate change called Heating Up, by Fiona Harvey, and two editorials on the science and the politics that get the call for action exactly right:

• The best solution is a global cap-and-trade system.
• All major emitters need to be under the cap as early as possible: a lesser obligation by developing countries "is a case for more generous quotas, not an excuse from signing up for a global emissions target."
• The private sector and carbon markets are the best way to generate the scale of investment necessary to make the turn to climate safety a reality.

We know that with clear economic signals we can redirect much of the capital we are already spending on carbon-intensive infrastructure to cleaner renewable fuels. We currently spend $5 trillion annually on fossil fuels.

We also know that within the next decade all major emitting countries must start getting on a downward trajectory in carbon emissions.

The only path is to cap U.S. emissions and reach a strong global deal without delay.