The agreement reached last week lends fresh urgency to challenges in science and communication.
It is easy to feel disappointed by the accord brokered last week by US President Barack Obama at the United Nations Framework Convention on Climate Change in Copenhagen. The document's broad outlines do not constitute a treaty, nor is it even clear whether it should technically be called a global agreement. Crafted principally by a handful of nations — the United States, China, India, Brazil and South Africa — the accord was presented as a take-it-or-leave-it fait accompli to representatives of the nearly 200 other nations in attendance, few of whom had been consulted. The resulting protests nearly led to the convention's collapse (see page 966).
The accord provides a framework for capturing the national climate commitments already on record, but has no mechanism to enforce them. Nor does it offer any global emissions targets. Even if fully implemented, the accord would allow greenhouse-gas emissions to continue rising beyond 2020, and would put the world on a course towards a warming of nearly 4 °C by 2100. It would not halt the acidification of the world's oceans or the melting of its ice. It is so weak that many critics worry that it will actually undermine progress by failing to send a clear signal to markets, investors and governments about the need to reduce greenhouse-gas emissions.
Nonetheless, for the first time, all of the world's largest greenhouse-gas emitters have signed up to a framework for cooperation on the biggest challenge of our time. For all of its shortcomings, the accord is an important step forwards.
“Scientists need to develop a better understanding of the full suite of physical processes affecting the planet.”
In many ways, the accord represents a snapshot of humanity at a crucial juncture in history. Tensions between rich and poor, north and south, past and future, all came to the fore during the Copenhagen conference, and right up to the moment Obama announced the accord, it was unclear whether the meeting would produce anything. Even then, the agreement was so controversial that the convention was unable to adopt it as a formal decision; instead it was recognized as a proposal that countries can sign up to if they so choose.
In fairness, formal adoption was blocked by just a handful of countries — which was all it took under the UN consensus rules that governed the conference. Those rules, which make it extraordinarily difficult to get anything done through the UN framework, are perhaps the strongest argument for the more bottom-up approach epitomized by the Obama deal. Instead of waiting for a top-down, global consensus, it may be better to build on the international momentum that has been achieved by individual nations pursuing their own goals on climate.
Such individual efforts can reinforce one another, even without explicit global coordination. Consider the climate bill that is pending in the US Senate. Members of that body are wary of committing to caps on greenhouse-gas emissions if they think that developing countries can continue to emit greenhouse gases at will — a perception that doomed Senate ratification of the 1997 Kyoto Protocol. This time, all of the major emerging economies prepared for Copenhagen by assessing what domestic greenhouse-gas cuts they were prepared to make. This is crucial for any meaningful action on climate, as the developing world will be responsible for virtually all of the growth in greenhouse-gas emissions in the decades to come. It also means that these countries are more likely to meet their commitments, because the goals are not just numbers imposed from above by a UN-wide consensus. Under the accord, moreover, those commitments will be public knowledge, which should make it easier for the international community to review each nation's performance — a requirement that Obama explicitly sought in Copenhagen. That, in turn, should help his administration in the monumental task of pushing the climate bill through Congress next year.
Investments in the future
The developing countries, meanwhile, got the Copenhagen accord's promise of some US$30 billion during the next three years and $100 billion annually by 2020 to help them cope with global warming. Some of that money will go towards forest conservation, helping to curb the significant releases of carbon that result from deforestation (see Nature 461, 1048–1052; 2009). But the money could also be used to help poor nations adapt to a changing climate, work on sustainable development plans or pay for low-carbon energy technologies. This promise represents a significant transfer of wealth from rich nations to poor, and may be only a down payment: some advocates have argued that the $100-billion commitment must be tripled to get the job done. Many politicians in the rich nations have rightly come to view this money not as a donation, but as an investment; everyone will pay a far larger price down the road if poor countries follow the conventional carbon-intensive pathway to development.
In an ideal world, negotiators would have come to the table with such commitments and then used them as a foundation for an even stronger agreement. But that kind of negotiating requires trust, which proved to be in short supply in Copenhagen. For now, the world will have to live with a collection of national commitments that can, over time, be built into something stronger.
The next opportunity will be during the first review of implementation and commitments under the accord, which is scheduled to be finished by 2015, one year after the completion of the fifth assessment of the Intergovernmental Panel on Climate Change (IPCC). The IPCC's alarming fourth assessment in 2007 set the stage for Copenhagen, and the world mobilized as a result. The fifth assessment will be just as important.
But key messages for citizens and their leaders have emerged from the continual observations of the state of the planet since the fourth assessment. It is essential that the vigour of such research be sustained even in the face of tight budgets and an anaemic world economy. Scientists need to develop a better understanding of the full suite of physical processes affecting the planet, from cloud formation to feedbacks that affect the way the climate responds to greenhouse gases and other perturbations, whether natural or caused by humans. They particularly need the computational resources to improve regional climate forecasting. Although there is good agreement about how climate will change on a large scale, there is considerable uncertainty over changes at the local and regional level, which is the kind of detail required by governments for planning purposes.
Researchers have also made significant progress in assessing and monitoring carbon in forests, but need to do more to develop a holistic view of carbon trends across farms, cities, wetlands, oceans and every other part of Earth. Also crucial is a renewed emphasis on agricultural research — until recently a comparatively neglected discipline, but one that is essential to counter the effects of global warming, feed a growing population and support efforts to reduce deforestation, of which agriculture is a primary driver. The social sciences, which are rightly receiving more emphasis in the IPCC's fifth assessment exercise than they have in previous rounds, are likewise important: a better understanding of people, communities and society should be central to devising solutions that realistically can be implemented.
A crucial challenge for researchers over the next few years will be to ensure that public communication of the results of climate-change research — whether formally or in the blogosphere — is robust in every sense: making the results comprehensible, and even vivid, yet rigorous; doing full justice to the uncertainties; maintaining such standards in the face of misinformation and propaganda; and responding promptly to the unexpected.
But governments have the biggest challenge of all. In the face of major threats to their countries' long-term futures, they need to commit to an international treaty. They also need to sustain the bottom-up motivation for change. They must empower their citizens with information: not only about what science is saying, but also about citizens' own contributions to the problem. New energy technologies will be required, but the quickest returns on investment in mitigating climate change and its effects can be found in energy efficiency and incentivizing behavioural change.
About this article
Comment se construit la confiance dans les sciences et les politiques du climat ? Retour sur un colloque international
Natures Sciences Sociétés (2015)