Climate change is often described as the greatest environmental crisis faced by the world. So what is the significance of the unfolding global financial crisis for the "climate crisis"? Might it lead to a retreat from concern, a resurgent interventionism or a reflection on society's deeper dilemmas?

Mike Hulme is professor in the school of environmental sciences at the University of East Anglia. His next book is Why We Disagree About Climate Change (Cambridge University Press, February 2009). His website is here

Also by Mike Hulme in openDemocracy:"Climate change: from issue to magnifier" (19 October 2007)"Climate security: the new determinism" (20 December 2007)

"Climate change" involves far more than a measured description of evolving trends in regional or global weather statistics or an uncomplicated account of the changing biogeochemical functions of the Earth system. How we talk about climate change - our discourse - is increasingly shaping our perception and interpretation of the changing physical realities that science is battling to reveal to us. At that same time, discourse is always embedded in evolving cultural, political and ethical movements and moods. Not only is our climate unstable, but how we talk about our climate is also unstable.

Understanding climate change - and the meaning we attach to the idea - is therefore always historically contingent. A sequence of four influential themes that have emerged over the last four decades illustrates the point. The idea of anthropogenic global climate change first became a possibility following the emergence of the 1960s environmental movement; the phenomenon became fully globalised during the triumph of economic globalism during the 1980s and 1990s; climate change then became part of new security discourses which emerged after 9/11; while following the Stern report on the economics of climate change in 2006, climate change has been viewed by some as merely a consequence of market failure.

The onset of the financial crisis and a gathering worldwide recession, signalled by the banking collapses and emergency bailouts of September-October 2008 - make it plausible to anticipate that this period too will generate its own characteristic frame of reference. So how will this latest manifestation of economic globalism change the way we think, talk and act about climate change? What may this new global turn eventually do to climate - both materially (by modifying the flows of carbon-dioxide through the planet) and culturally (by modifying the rhetoric and language of climate change)?

The three pointers

Climate change is a powerful symbol of the current zeitgeist. It is a hybrid phenomenon that reveals and is revealed by a number of important political, economic, intellectual and psychological dualisms: global-local, north-south, material-cultural, fear-hope, control-vulnerability. As we vacillate between these poles of thought and action, so too does our talk of climate change and with it our understanding of the phenomenon and what it means to us. Climate change becomes a continually mutating hybrid entity in which scientific narratives are unavoidably entangled with wider social discourses (see "Climate change: from issue to magnifier", 19 October 2008).

Also in openDemocracy on the global financial crisis of 2007-08:

Willem Buiter, "The end of American capitalism (as we knew it)" (17 September 2008)

Ann Pettifor, "The week that changed everything" (22 September 2008)

Fred Halliday, "The revenge of ideas: Karl Polanyi and Susan Strange" (24 September 2008)

Godfrey Hodgson, "The week that democracy won" (29 September 2008)

Tony Curzon Price, "Unprincipled madness" (1 October 2008)

Grahame Thompson, "Deglobalising the crisis" (3 October 2008)

Will Hutton, "Wanted: a fairer capitalism" (6 October 2008)

There are many directions in which this hybrid entity of climate change may evolve in the months and years ahead, in parallel with persisting economic problems and accompanying social dislocation. Just as the physical climate- system responds both to slow-changing natural rhythms and also to more rapid human-induced perturbations, so will those human artefacts we use to make sense of climate change - language, metaphors, policies, beliefs - respond both rapidly and slowly to the new financial and economic mood. I suggest these social responses may fall into one of three meta-categories:

* a retreat from concern about climate change

* a resurgent support for state policies on climate change

* a deeper reflection about the human drivers of climate change.

The warm echo

The first response is seen in the instinctive reaction of some commentators to questions about the significance of the financial crisis for climate change: that the bursting of the credit-bubble will be mirrored in the bursting of the climate-change bubble. The adherents of this view will mobilise historical precedent (such as the collapse of surging environmental populism in Europe following the 1991 recession) to argue that the new recession will reveal the shallowness of the commitments of political leaders to effecting far-reaching reductions in carbon emissions.

The gradual dilution of the European Union's 2020 carbon-reduction target is reflected in the opposition of east-central European states to the auctioning of emissions-permits, and in the further transfer from Europe of "real" physical emissions-reductions to the "purchased" emissions-reductions of the global south; the outcome might support the contention that in this region at least, economic uncertainty is likely to be followed by environmental retreat.

The second response, and a counter-argument to the above, is that the financial crisis will provide just the confidence-boost that is needed for neo-Keynesian interventionist policies on climate change. If banks can be brought under state control through massive injection of borrowed funds, then surely new waves of state investment targeted at low-carbon energy supply and energy-efficiency technologies can be secured. This was the basic argument outlined in the "green new deal", launched in July 2008 by the new economics foundation before the financial crisis fully matured; it is a case repeated by other voices such as Elliot Morley, president of GLOBE International (see his speech in Washington on 11 October 2008 to the International Commission on Climate and Energy Security).

This argument of "crisis-as-opportunity" also resonates with the influential thinker Anthony Giddens's call for the old "enabling state" to evolve into the new "ensuring state" (see "The politics of climate change", Policy Network, 8 September 2008). This would require certain collectively-defined emissions-outcomes to be ensured through appropriate regulatory frameworks. To achieve the putative goals of climate policy under such a dispensation would call for, if not quite the discredited heavy-handed state collectivism of earlier ideologies, then a new "green" authoritarianism within western liberal democracies. In Britain for example, it is hard to see how else the climate-change minister Ed Miliband's adoption of a minimum 80% reduction in carbon-emissions by 2050 will be secured. Voluntarism in climate change, this argument would suggest, may soon seem as outdated an axiom as self-regulation of capital markets now appears.

openDemocracy writers debate the politics of climate change:

Stephan Harrison, "Glaciers and geopolitics" (27 May 2005)

Saleemul Huq & Camilla Toulmin, "Climate change: from science and economics to human rights" (7 November 2006)

Simon Retallack, "Climate change: the global test" (10 November 2006)

Tom Burke, "Climate change: choosing the tools" (21 December 2006)

John Elkington & Geoff Lye, "Climate change's right and wrong fixes" (2 February 2007)

Dougald Hine, "Climate change: a question of democracy" (2 March 2007)

These two reactions to the financial crisis - a retreat from concern and a resurgence of regulation - appear diametrically opposed. Yet each reveals a conservative understanding of the fundamental conundrum which underlies climate change. Neither attempts or engages with any deep diagnosis of the climate-change phenomenon. A third response, less articulated at present than the other two but already visible, may by undertaking this task come to offer a new set of directions: whereby the financial crisis could move our discourse about climate change towards wider challenges to our values, our lifestyles and our (implicit and explicit) judgments about human well-being.

These challenges may range from questioning the ethics underlying institutional forms and practices to questioning the values and aspirations of individual citizens. Jonathon Porritt, for example, calls for a recognition of the parallels between financial and ecological debt (see Jonathon Porritt, "Zero hour for a new capitalism", Green Futures, October 2008); and this is itself an upstream economic version of the argument already articulated in WWFs report Weathercocks and Signposts (April 2008)

The latter suggests that no substantial progress on climate-change goals will be secured without confronting the prevailing "extrinsic" values (material goods, financial success, image) by which society largely operates, and replacing them with "intrinsic" values (personal growth, emotional intimacy, community involvement). This implies no less than a wholesale reframing and redirecting of human development. If we apply the scenario categories of the Intergovernmental Panel on Climate Change (IPCC's) special report on emissions scenarios, the WWF report advocates a future that looks and feels more like the "local stewardship" (B2) scenario than the "global affluence" (A1) world. Such a project of social restructuring resonates too with the "low-energy cosmopolitanism" postulated by Andrew Dobson and David Hayes (see "A politics of crisis: low-energy cosmopolitanism", 22 October 2008).

The inner cost

The financial crisis that has shaken the world in autumn 2008, and the recession trailing in its wake, will at the very least make us realise that an adequate reading of climate change is about very much more than "getting the science right" or deploying clever Earth-systems models that offer predictions of approaching climate tipping-points. The future course of climate change - understood as a hybrid physical-cultural phenomenon in which science and our social discourse are enduringly entangled - has many more dimensions than those that can be represented numerically in a model.

The financial crisis, seen in an optimistic light, may yet do more than this. It may help us see that climate change isn't the greatest demon we humans have to confront; rather, our demons reside in the values we live by. If it causes us to expose the impossible arithmetic of more-people-plus-greater-material-consumption-plus-higher-levels-of-debt equals-an-improving-quality-of-life, then it may do more for climate change than any number of economic or political interventions.