Katrina Forrester (London, Plane Stupid): In the last months we have seen a surge in environmentally driven political action. The UK's anti-aviation movement is being propelled by local residents and activist groups uniting to challenge the current Heathrow Consultation. The Green Party has agreed to elect a leader, highlighting the need for engagement at a party political level. The scene is set for widespread global change. We hope.In times of crisis leadership is necessary. Difficult times call for new political direction. What, then, is the political solution to the global crisis we now all face?

If we had time to remain in what climate scientists call the ‘business-as-usual' scenario, I would still be calling for local, grassroots solutions. I would be emphasising the need, above all else, for a more participatory framework for our political system. I would be looking to models for collective co-ownership of resources, to systems of community empowerment and de-monopolisation.

But, as we all now know - whether or not we acknowledge it - we are in a state of planetary emergency. To use the language of apocalypse that so many shy away from, we are at the tipping point of the next major extinction event. And this time it's anthropogenic. The ‘business-as-usual' scenario, for politicians as well as radical activists, is no longer an option.

Where does this leave us politically? I, for one, doubt that we can revolutionise our entire political system, devolve power and decision making, in time to stop runaway climate change.

Must we therefore rely on traditional models of leadership within national and international frameworks in order to get us out of the state we're in?

My answer is both yes and no. Acceptance of established structures is vital to our attempts to reach the target of stabilisation at 2°C above pre-industrial level that will maybe, just maybe, stop the acceleration of dangerous climate change.

But this acceptance should not, however, be equated with widespread political disenfranchisement. It must not. We now have the opportunity to accept the challenge of global empowerment at the local level.

Now is the time for political renewal, however millenarian it may sound. This in part means putting pressure on our existing leaders truly to act in our names. As for that other traditional source of hierarchical power, the global capitalists, since some of them have become ‘ethical' and ‘philanthropic', we need to call these in increasing numbers to account on investment in new energy technologies, while disinvesting in those which bring planetary doom in their train. It is not a question of following them: they must follow us.

Leadership does not have to be synonymous with hierarchy. We need leadership by both groups and individuals to squeeze results from the empty rhetoric of politicians. In his Climate Change speech on the 19th of November Gordon Brown stated his concern for "concrete action", rather than "vague promises". We must hold him to this. Our politicians must feel they have a mandate based on public opinion that enables, and ensures, action. And so, direction and engagement at all levels is necessary. Home grown activism can shape the behaviour of our sovereign parliament.

The protests last month at Ffos-Y-Fran in Merthyr Tydfil, Wales, in opposition to a new opencast mining scheme demonstrated clearly the new alliances between activists, residents and major political commentators. Local and global interests are beginning to coalesce. We all now, as a planet, must fight the same fight: we have everything to lose if we do not act. We must lead from above and below with what we have at our disposal: direct action, civil disobedience, party politics, localised democracy, global cooperation: the traditional and the radical. This is a time for leadership on all fronts. We must now put the politics back in Politics. And as we struggle for this common cause, political structures might just reinvigorate themselves.