Interview: Germany's top climate adviser

Correspondent Mariah Blake in Hamburg, Germany, talked with Hans Joachim Schellnhuber upon his return this weekend from the Bali talks, where he was a member of Germany's negotiating team. Below are excerpts from the interview.

Q: Emotions were clearly high in Bali. What accounted for the intensity?

A: The general mood was different than in past years because everyone has accepted that the science is real, that climate change is happening.

I was also a member of the German delegation back in 1997 when the Kyoto Protocol was signed. Behind the scenes, everyone was questioning whether the science could be trusted. Many delegates seemed to think the problem might just go away. This meant that they could just go back home and worry later about whether they had to fulfill their obligations.

Now ... everybody knows that if you make a commitment you have to stick to it. This will mean big changes in policy because it will be extremely difficult to achieve what is necessary in order to avoid dangerous climatic change.

Is the Bali road map a success?

I would say the European Union has achieved probably 60 or 70 percent of what it set out for. There is a mandate. There is a negotiation plan. There is a timetable. And – very important – all parties are on board, including the developing countries and the US, which is not a party to the Kyoto treaty. Also, science is calibrating the whole process.

There has been a lot of focus on the fact that the US was forced to back down. But it didn't back down on its refusal to include specific emissions targets.

It's true that there are no specific targets [in the Bali road map], but ... there is language that talks about comparable measures for all parties. That points directly to the US and suggests targets.

... We wanted to craft wording ... so the next US government can, if it chooses, do something more ambitious about climate change. There is now the option to do so. I've met with American officials – Democrats and also Republicans – who want to take bolder steps. So in the end it's in the power of the American electorate next year to decide what the Bali road map really means.

What can countries such as the US do to encourage developing nations to cut emissions?

The role of the industrialized countries is to demonstrate that you can protect the climate and nevertheless prosper and increase your well-being as a society. Germany has now put together a package for a 40 percent reduction of emissions – very ambitious, but we did the calculations and in the end it will save us money.

I'm absolutely sure that if we are able by 2020 to demonstrate [the economic benefits of climate protection], then China and Africa and other countries will simply come on board. The US is in a particularly strong position to lead.

What will make the new climate treaty truly effective?

In particular, we need to be on an emission-reduction path that doesn't allow global temperatures to rise more than 2 degrees [Celsius] above pre-industrial levels. This is very ambitious. But we know if we get into the 3-5 degrees realm, we will be faced by major crises like a complete meltdown of the Greenland ice sheets, a collapse of the Amazon rain forests, a sea-level rise of 10 or 20 meters in the long run. So the goal has to be clearly spelled out, and it has to be as simple as possible. Of course, achieving this kind of simplicity can be extremely complicated.