New research shows what's needed to stop dangerous climate change

Mike Childs

19 September 2012

Is it too late to stop dangerous climate change without geoengineering? This is probably the question now most often asked of climate scientists and campaigners. It is also the focus of new research just published by the Met Office and others.

 The Met office report says that to give even a 50:50 chance of avoiding a 2 degrees global temperature increase requires a global peak in emissions by 2016 and emissions reductions of 3.5 per cent every year afterwards. It also says the lowest we can keep global temperature rises to is 1.6 degrees but to do so would require global emissions peaking at 2014, a 4.5 per cent per year reduction in emissions after this date and the highest level of negative emissions possible. Negative emissions are taking carbon out of the air.

This research obviously raises a number of important issues:

• When is it realistic to get a peak in global emissions?
• Is a reduction in emissions of 4.5 per cent per year achievable?
• Is the maximum negative emissions potential the Met Office modelled really the maximum?

I'll address each of these in turn.

• Peaking date - global emissions have continued to increase through the years despite the fact that most of the technologies to reduce emissions are already available. A global peak in 2014 or 2016 would require heroic actions, although we should demand nothing less.
• Reduction rates - global average reduction rates need to take into account that some developing countries emissions are likely to need to increase in coming decades. The maximum 4.5 per cent decline in global emissions suggested by the Met Office would therefore require faster emissions reductions in developed countries and other major emitting countries. The Met Office research already claims to be ambitious with this reduction rate and, although one should never rule out the potential of humanity to do amazing things, it does at this stage appear to be ambitious.
• Negative emissions - if the peaking dates in the Met Report seem overly optimistic, and the emissions reductions rates challenging, can we deliver more negative emissions than the Met Office assume. Firstly, it's important to be clear that the Met Office report was not unambitious in terms of negative emissions. However, their report only considered one type of negative emissions technique - burning biomass as storing the carbon released underground - and not many of the other techniques that may be available,  as showcased in our report last year. In our report it was estimated that there was significantly more potential for negative emissions than the Met Office report suggested, which could allow for a later and perhaps more realistic peaking date - although it is only a potential as many of the techniques are not yet demonstrated at scale.

The broad conclusions that should be drawn from the Met Office report are: we should achieve a peak in emissions as quickly as possible; emissions cuts need to be deep; and that we should with urgency be developing and deploying negative emissions techniques.

In other words, it's not too late, yet!