Author: Will Steffen, ANU

Not surprisingly, interpretations of the outcome from COP15 range from an outstanding success to an utter disaster, and everything in between.  Political leaders claim a big step forward towards climate protection, while the vast majority of the NGOs who flocked to Copenhagen blast the outcome as, at best, a wasted opportunity.

In many ways, views on the outcome of COP15 were strongly conditioned by expectations, especially for those who thought that the Copenhagen conference would ‘seal the deal’ for limiting anthropogenic climate change to a temperature rise of no more than 2 degrees Celsius above pre-industrial levels. But a comprehensive, final agreement was never really in the cards, even months before the meeting itself. The real question was whether COP15 would make enough progress to build unstoppable momentum towards a much tougher, legally binding agreement sometime in the next 6 to 12 months. Read more…

Author: Will Steffen

A new report published by the United Nations Environment Program this week caused some media stir and alarmism over the issue of aerosols in the atmosphere – now popularly referred to as ABCs (Atmospheric Brown Clouds).

The issues are well-known in the scientific community, and have been part of global change research for a couple of decades at least. The issue has only recently found its way into the popular press.

Aerosols are particles of various sizes emitted into the atmosphere by both natural and human processes. In some parts of the way – for example, around the Asian mega-cities – human-driven emissions of aerosols, primarily through the combustion of fossil fuels and of biomass for heating and cooking – now dominate the natural sources.

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Author: Will Steffen

The Garnaut Review has done a superb job of laying out the climate change dilemma in all its complexities as well as pointing the way forward. To those focused on finding solutions – costing climate change and its avoidance, developing an Australian emissions trading scheme, working towards global agreement and enhancing global collaboration, transforming energy systems, and much more – there is complexity enough. But the climate science itself, which provides an underpinning knowledge base on the nature of climate change, is also providing complexities of a rapidly changing nature.

Although the IPCC’s Fourth Assessment Report (AR4) provides an excellent scientific base for the climate change issue, the scientific landscape is changing more rapidly than we thought possible. One of my colleagues has stated that “…the Earth is moving faster than the science…”, and I could add that the science is now moving faster than policy development. The most recent research on the stability of the large polar ice sheets and on the dynamics of the natural carbon cycle illustrates this phenomenon. Read more…