The message from Rio+20 is for practical action to deliver existing targets. Scientists must identify and overcome barriers to change.
Sha Zukang, secretary-general of Rio+20, held a press conference in Rio de Janeiro on 13 June, heralding the start of the final phase of negotiations at the UN Conference on Sustainable Development. He stressed that this meeting is fundamentally different to the first Earth Summit, held in Rio in 1992.
Twenty years ago, the meeting produced a legally binding document including conventions on biodiversity, desertification and, ultimately, climate change. The Rio+20 outcome agreement, to be negotiated next week, has no basis in law, said Sha it is voluntary and political, and its goal is practical action.
This is a meeting born out of gloom that so little has been achieved, as shown by the UN Environment Programmes GEO-5 report launched last week.  The question is, can the science, technology and innovation (STI) communities deliver yet more to further the cause of sustainable development and avert some of the environmental crises they have predicted?Indeed, the agreement will seek commitment to deliver on what had previously been agreed in 1992 a long list of largely unattained targets.
Science has its own barriers
In some ways it is hard to see what else they can do, as STI seems to have several intractable issues of its own.
Scientists concerned about global change complain repeatedly that a fault in their community is the silo mentality. This behaviour is thought to undermine the potential of science to deliver solutions, which is why there has been a revamp of the CGIAR agricultural research programmes and the formal launch of the immense enterprise of Future Earth this week.
There is undoubtedly a lot of truth in this. But it is also true that many scientists are driven by in-depth understanding in their area of research. Forcing them to behave differently for example to contribute to Shas call for practical solutions rather than exploring why things happen goes against that drive.
Another barrier to the further contribution of the STI community to sustainable development is that implementation of their discoveries and inventions is often beyond their expertise.
Implementing ideas without taking into account the wider context, runs into the problem that life is interconnected and messy, as we are increasingly told in reports such as People and Planet or The European Review of Development. An intervention, such as the conversion of a food crop field to a biofuel plantation, has effects on water resources and food security, which can go far beyond the original attempt to improve energy availability.
Finally, there seem to be limitations to the extent to which scientists can communicate with policymakers and interest groups about the state of the planet.
Scientists do deserve credit for keeping alive over the past year a fear of the consequences of inaction at Rio+20. But there is a limit to the extent to which the facts can galvanise practical action when they have to compete for attention with ideology, international relations, national sentiment and lobbyists pursuing single (though sometimes worthwhile) causes.
There are 20,000 members of civil society registered for the Rio+20 conference. Scientists cannot make full use of the same PR techniques of these other groups without undermining their core selling point their reputation for independence.
Agenda for practical action
But there are ways round these obstacles.
Research funders who pursue multidisciplinary, collaborative, global research agendas must acknowledge that they need to seek a new type of scientist to carry it out one with a mentality and training that fits the new scientific order of problem-based research.
Furthermore, the links that natural scientists are pursuing with social scientists, to establish new types of research programme, should be pushed to a more radical conclusion. Social scientists should be put in charge of research programmes rather than just invited in as collaborators.
To tackle the problem of applying neat solutions in a messy world, those working in STI need to try to work with human nature, not against it. Instead of making nave calls for changes in values or behaviour as some scientists did at the Planet Under Pressure meeting and previously they need to work with things as they are.
That is why grassroots innovation has so much potential because it harnesses human ingenuity where resources are limited. Similarly, the desire to own devices such as mobile phones, six billion of which are now in use around the world, needs to be exploited, and the broadband divide needs to be tackled to develop innovation for sustainable development.
Finally, despite the limits that scientists have found in trying to galvanise action through presenting the data, there is still a lot to be done regarding communication.
Multidisciplinary conferences should be assessed, difficult though this may be, to find out what benefits they delivered, how they should be evaluated, and how they could be improved. Planet Under Pressure was a brave attempt at just such a meeting, but some delegates said its structure stifled interaction between the disciplines and full-blooded discussion.
The cause of improving communication needs to be pursued at a local level as well. In Indonesia, scientists working with ELRHA (Enhancing Learning and Research for Humanitarian Assistance) have successfully liaised with local leaders, allowing a flow of data which has helped them develop tsunami preparation systems. This kind of approach needs to be replicated.
STI researchers can contribute more to realising Shas practical agenda for sustainable development. But they need to recognise what science can change and make these changes and what it cant. The latter they will have to leave to the expertise of someone else.
Consultant News Editor, SciDev.Net
 UN Environment Programme. Global Environment Outlook (GEO-5)