The United Nations Framework Convention on Climate Change (UNFCCC) was set up at the Earth Summit in 1992. That’s 21 years ago and where are we? Atmospheric carbon levels have just hit 400ppm for the first time in human history and emissions show no sign of slowing. We’re running out of time.

Is it time to admit that, no matter how many international jamborees held or acronyms forged, trying to agree an over-reaching framework of targets, processes and systems that will satisfy Beijing, Washington and Dar es Salaam just ain’t gonna happen?

On the other hand, we know what will happen if we don’t have some form of international agreement. Nations that take action will lose polluting industries to those who won’t, creating to a race to the bottom and no reduction in emissions. The Tragedy of the Commons writ large.

This is a conundrum I’ve been wrestling with for a long time and I’ve come to the conclusion that simplicity is the answer. Just think about when you get overwhelmed at work – trying to do too many things at once just leads to you rushing around like a headless chicken and getting nowhere fast. The only solution is to list what needs doing, pick the one which will give you the biggest return on your efforts, and focus on that ’til it’s done.

So if you could pick just one thing to do on the climate, what would it be?

My vote goes for a carbon tax in every nation. A carbon tax is very simple, penalises carbon intensive energy (eg coal) more than cleaner energy sources (renewables), and some countries have already gone down this route so we have some experience to build on. If every UNFCCC country committed to impose a carbon tax then, in theory, there would be no carbon ‘leakage’ as industries would find a similar regime in place wherever they went. Nations could spend the revenue raised as they see fit to avoid ‘World Government’-type paranoia.

In order to prevent poor countries being penalised, the level of taxation in each country could be linked to per capita GDP. This could lead to limited carbon leakage initially, but growth and carbon emissions would be decoupled.

This approach would lead to immediate action on carbon emissions, rather than arguing over targets which, once agreed, might lead to reduced emissions at some point in the future – and might not.

Once a such a global carbon tax agreement was agreed and implemented, then the UNFCCC could start looking at other issues one by one, such as protection of forests, targets, development mechanisms etc. These would have to play second fiddle in the medium term, but at least we’d have one practical measure up and running and cutting carbon, rather than yet another avalanche of position papers.

So let’s keep it simple and actually do something. Carbon taxes for all!