To start with, it would take at least couple of thousand years of dwelling in biodomes while the right conditions to live in the open air were created. For Mars lacks Earth's "greenhouse effect", a layer of "greenhouse gases" that trap solar energy, creating an atmosphere in which humans can live. Without this Earth would be as cold and barren as Mars. However, the greenhouse effect needs to be carefully balanced to support human life. Too high a concentration of greenhouse gases and the planet would overheat, leading to unpredictable weather behaviour, loss of plant and animal species, and serious disruptions to the chain of life on Earth. This is human beings" most urgent habitat problem today - the concentration of greenhouse gases in Earth's atmosphere, particularly carbon dioxide, is currently on the rise, pushing the temperature up with it. In the last two decades in particular the Earth warmed at a rate faster than at any point in at least the last 1000 years. And, while scientists have tested alternatives to the idea that human beings are affecting global climate, none of the factors such as the climate's natural variability or changes in solar radiation fit the 20th century's observed warming so well as increases in greenhouse gases generated by human activity. The question of what it would take to support human life is more pressing for planet Earth than for Mars - as a species we are having difficulties taking steps to ensure that we can carry on living in our present home.
International political response to the deterioration of support systems for human life on Earth comes in the form of the UN's Kyoto Protocol, a set of negotiations that calls for token cuts in greenhouse gas emissions. Ratification of the Protocol is stalled by Russia's vacillating over whether to sign the agreement. Meanwhile the US has simply refused to play, an unsurprising stance given that the main cause of climate change is too much carbon dioxide in the atmosphere. This carbon dioxide comes from the burning of fossil fuels, most notably oil, and the US is at least as addicted to oil as is the rest of the global North.
How disturbing: the resource that fuels contemporary society and defines international relations is the same resource that most severely impacts on the ability of our species to survive. Carbon dioxide is emitted in the manufacture of almost every product that we buy and in every journey we make by motorised vehicle. For the past four decades, the output of carbon emissions and Gross Domestic Product from globalised industry have increased almost exactly in proportion to each other - a dramatic cut in emissions would mean a correspondingly dramatic shift in our understanding of "business as usual". The scale of changes that are implied, even if motivated by an interest in future human generations being able to live on this planet, seem difficult to accept. Such measures are hardly vote-winners. This is why a meaningful attempt to tackle climate change is not at the top of most politicians" agendas.
This is also what makes questions over a radical transformation of society immediate and practical, rather than abstract. It is less a case of whether transformation should happen, and more of a case of what sort of changes are required. Thus, to avoid panicked measures and an increasingly authoritarian state, human beings need to find a way of practising politics that allows for participation in this significant political transformation. What mechanisms need to be developed to allow people to decide on the limits to carbons emissions? How will those limits be applied in a truly free and fair manner?
Fortunately, there is no need to start from scratch on this last question. The UK-based Global Commons Institute has put forward an initiative, Contraction and Convergence, which would provide a way for the global community to move towards the 80% emission cuts necessary to prevent carbon dioxide levels from exceeding twice what they were before the industrial revolution. And Contraction and Convergence is based in the principle of equity, recognising that such vast change needs a political framework. The Kyoto Protocol is often criticised for being "too little, too late" but it is predictably so, given that it challenges none of the economic or political assumptions of a capitalist system. It relies on the extension of the market to the Earth's carbon dioxide recycling facility - the atmosphere -to get us out of this mess. It allows those who usually use more than their fair share of the world's resources to continue doing so. As a step beyond Kyoto, Contraction and Convergence recognises that safeguarding life support systems for future generations has to involve a different way of working from the current, clearly defunct, system.
Contraction and Convergence proposes that international "shares" of greenhouse gas emissions be allocated on the principle of equity, whereby a human being in an over-consuming country has no more nor less right to Earth's atmosphere than a human being in an under-consuming country. From this understanding the initiative proposes that countries in the United Nations Framework Convention on Climate Change agree a global greenhouse gas emissions 'contraction budget', aiming to limit atmospheric concentrations of these gases. Shares of greenhouse gas emissions would be proportional to an agreed base year of global population. In practice this may mean that over-consumers of greenhouse gases would have to contract sharply, while under-consumers could continue to rise for a while until their overall consumption "converged" at the pre-agreed level. Contraction and Convergence has solid scientific grounding with the aim of fair distribution, and with the atmosphere afforded the status of a common resource for all life on Earth.
In a January 2000 report, Greenhouse Gangsters vs. Climate Justice, the US-based group CorpWatch summed up the changes needed as being about more than weather stabilisation. They called for "climate justice", including the recognition that communities hit hardest by the extraction, refining and distribution of fossil fuels are not only some of the most severely impacted by climate change catastrophes but are also some of the least capable of responding to them. As part of a movement for climate justice CorpWatch's stance included opposition to -military action, occupation, repression and exploitation of lands, water, oceans, peoples and cultures, and other life forms, especially as it relates to the fossil fuel industry's role.- They accused multilateral development banks, transnational corporations and governments in the global North of compromising the democratic nature of the United Nations as it attempts to address the problem. The obstacles to achieving weather stabilisation as part of a larger goal of climate justice are, after all, both institutional and political. Despite a potentially bleak prognosis for the survival of human beings on Earth, hope lies in understanding that climate change is the result of a tangible set of events and political decisions. And, as such, it does not have to be inevitable.