The International Scientific Congress Climate Change: Global Risks, Challenges & Decisions has closed, which now allows us to reflect upon what this effort actually achieved. Since its inception, the conference was designed to be a lobbying effort to shore up support for substantial international emissions reduction targets under the post-2012 regime. As such, there was much talk about the "new" and "more urgent" science that has emerged and its implications for climate policy. However, if one examines the "key messages" emerging from the conference organisers, there seems little in the way of new information:
Key Message 1: Climatic Trends
Recent observations confirm that, given high rates of observed emissions, the worst-case IPCC scenario trajectories (or even worse) are being realised. For many key parameters, the climate system is already moving beyond the patterns of natural variability within which our society and economy have developed and thrived. These parameters include global mean surface temperature, sea-level rise, ocean and ice sheet dynamics, ocean acidification, and extreme climatic events. There is a significant risk that many of the trends will accelerate, leading to an increasing risk of abrupt or irreversible climatic shifts.
Key Message 2: Social disruptionOf the above, nothing stands out as being particularly ground-breaking with expect to scientific discovery. In fact, these appear to be quite similar to standard statements akin to those emerging from organisations such as the IPCC. What is a bit out-of-the-ordinary is the statement: "Inaction is Inexcusable", which is hardly a scientific conclusion (see also Mike Hulme's essay here). This begs the question - how much of the latest Copenhagen conference was about science and how much was about the expression of policy preferences? Meanwhile, news reports about a recent Gallup Poll suggest the public are perhaps increasingly unconvinced by the constant rhetoric of "emergency" and "alarm". This is the point where science ends and policy begins - no degree of scientific investigation on climate change will necessarily lead to consensus over policy (see Roger Pielke Jr.'s The Honest Broker). As such, it is fair to question whether scientists do themselves any favours by continuing to blur the boundaries between science and lobbying.
The research community is providing much more information to support discussions on "dangerous climate change". Recent observations show that societies are highly vulnerable to even modest levels of climate change, with poor nations and communities particularly at risk. Temperature rises above 2C will be very difficult for contemporary societies to cope with, and will increase the level of climate disruption through the rest of the century.
Key Message 3: Long-Term Strategy
Rapid, sustained, and effective mitigation based on coordinated global and regional action is required to avoid "dangerous climate change" regardless of how it is defined. Weaker targets for 2020 increase the risk of crossing tipping points and make the task of meeting 2050 targets more difficult. Delay in initiating effective mitigation actions increases significantly the long-term social and economic costs of both adaptation and mitigation.
Key Message 4 - Equity Dimensions
Climate change is having, and will have, strongly differential effects on people within and between countries and regions, on this generation and future generations, and on human societies and the natural world. An effective, well-funded adaptation safety net is required for those people least capable of coping with climate change impacts, and a common but differentiated mitigation strategy is needed to protect the poor and most vulnerable.
Key Message 5: Inaction is Inexcusable
There is no excuse for inaction. We already have many tools and approaches (economic, technological, behavioural, management) to deal effectively with the climate change challenge. But they must be vigorously and widely implemented to achieve the societal transformation required to decarbonise economies. A wide range of benefits will flow from a concerted effort to alter our energy economy now, including sustainable energy job growth, reductions in the health and economic costs of climate change, and the restoration of ecosystems and revitalisation of ecosystem services.
Key Message 6: Meeting the Challenge
To achieve the societal transformation required to meet the climate change challenge, we must overcome a number of significant constraints and seize critical opportunities. These include reducing inertia in social and economic systems; building on a growing public desire for governments to act on climate change; removing implicit and explicit subsidies; reducing the influence of vested interests that increase emissions and reduce resilience; enabling the shifts from ineffective governance and weak institutions to innovative leadership in government, the private sector and civil society; and engaging society in the transition to norms and practices that foster sustainability.