The International Energy Agency warned on November 9th (see this article by the UK’s Guardian) that we face the prospect of irreversible climate change within five years if we do not immediately stop building fossil fuel dependency into our infrastructure.

“The door is closing,” Fatih Birol, chief economist at the International Energy Agency, said. “I am very worried – if we don’t change direction now on how we use energy, we will end up beyond what scientists tell us is the minimum [for safety]. The door will be closed forever.”

According to the article, “if the world is to stay below 2C of warming, which scientists regard as the limit of safety, then emissions must be held to no more than 450 parts per million (ppm) of carbon dioxide in the atmosphere; the level is currently around 390ppm. But the world’s existing infrastructure is already producing 80% of that “carbon budget”, according to the IEA’s analysis, published on Wednesday. This gives an ever-narrowing gap in which to reform the global economy on to a low-carbon footing.

If current trends continue, and we go on building high-carbon energy generation, then by 2015 at least 90% of the available “carbon budget” will be swallowed up by our energy and industrial infrastructure. By 2017, there will be no room for manoeuvre at all – the whole of the carbon budget will be spoken for, according to the IEA’s calculations.

Birol’s warning comes at a crucial moment in international negotiations on climate change, as governments gear up for the next fortnight of talks in Durban, South Africa, from late November. “If we do not have an international agreement, whose effect is put in place by 2017, then the door to [holding temperatures to 2C of warming] will be closed forever,” said Birol.”

Climate change is already happening and is a reality for many people around the world, for instance those in the Arctic who are already living with permafrost melt and changing seasonal temperatures and species patterns. Evidence is everywhere even in places that are not currently facing such rapid changes.

But the higher emissions go, the harder it will be to adapt to the impacts, and their reduction is the highest priority we face.

Here’s hoping the world does more in Durban than is currently forecast. As the article says: “after years of setbacks, an increasing number of countries – including the UK, Japan and Russia – now favour postponing the talks for several years.

Both Russia and Japan have spoken in recent weeks of aiming for an agreement in 2018 or 2020, and the UK has supported this move. Greg Barker, the UK’s climate change minister, told a meeting: “We need China, the US especially, the rest of the Basic countries [Brazil, South Africa, India and China] to agree. If we can get this by 2015 we could have an agreement ready to click in by 2020.”

Birol said this would clearly be too late. “I think it’s very important to have a sense of urgency – our analysis shows [what happens] if you do not change investment patterns, which can only happen as a result of an international agreement.”