Common sense was an early loser in the scorching battle over the reality of man-made global warming. For nearly 20 years, one group of activists argued - in the face of ever-mounting evidence - that global warming was a fabrication. Their opponents, meanwhile, exaggerated the phenomenon's likely impact - and, as a consequence, dogmatically fixated on drastic, short-term carbon cuts as the only solution, despite overwhelming evidence that such cuts would be cripplingly expensive and woefully ineffective.
This scientific pie fight, characterised by juvenile name-calling, ignoble tactics, and intellectual intransigence on both sides, not only left the public confused and scared; it undermined the efforts of the most important organisations working on advancing the science of climate change. Almost inevitably, at international summits from Kyoto to Copenhagen, governments failed to take any meaningful action on global warming.
Fortunately, there finally seems to be a growing number of influential scientists, economists, and politicians who represent a more sensible approach to the issue.
As I argued in my 2007 book Cool It, the most rational response to global warming is to make alternative energy technologies so cheap that the whole world can afford them. In broad strokes, this requires a deliberate and significant boost to research and development spending. Based on recent work by Isabel Galiana and Chris Green of McGill University in Montreal, Canada, I advocate expenditure totaling around 0.2 per cent of global GDP - roughly $100 billion a year.
Of course, no fix to global warming will work overnight. So we need to focus more on adapting to the effects of global warming - for example, by stepping up efforts to cope with inland flooding and the urban "heat island" effect. At the same time, we should explore the practicality of climate engineering, which we may need to buy more time for a smooth transition away from fossil fuels.
Acknowledging that man-made climate change is real, but arguing that carbon cuts are not the answer, amounts to staking out a middle ground in the global warming debate - which means being attacked from both sides. For so-called "alarmists," pointing out what's wrong with drastic carbon cuts is somehow tantamount to denying the reality of climate change, while so-called "deniers" lambast anyone who accepts the scientific evidence supporting this "mythical" problem.
Nevertheless, there are encouraging signs that the minority of sensible voices in this debate are beginning to get the attention they deserve. In mid-2009, as part of a project by the Copenhagen Consensus Center to assess different responses to global warming, Green and Galiana performed a cost-benefit analysis of R&D spending on green technologies. Green, a long-time proponent of a technology-led response to global warming, demonstrated the effectiveness of a policy of government investment in R&D aimed at developing new low-carbon technologies, making current technologies cheaper and more effective, and expanding energy-related infrastructure such as smart grids. As Green and Galiana bluntly noted: "No approach to climate stabilisation will work without an energy technology revolution."
Another academic who has advocated a smarter response to global warming is Roger Pielke, Jr of the University of Colorado, the author of this year's must-read global-warming book The Climate Fix. Along with Green, Pielke was one of 14 noted academics who co-wrote February's Hartwell Paper, commissioned by the London School of Economics and the University of Oxford. The paper made the case for developing alternatives to fossil fuels, ensuring that economic development doesn't wreak environmental havoc, and recognizing the importance of adaptation to climate change.
In the US, we witnessed an equally promising development in the climate debate just last month, when the conservative American Enterprise Institute, the liberal Brookings Institution, and the centrist Breakthrough Institute teamed up to publish a report that called for revamping America's energy system with the aim of making clean energy cheap.
Entitled Post-Partisan Power, the report comprehensively and convincingly argues that the US government should invest roughly $25 billion per year (about 0.2 per cent of America's GDP) in low-carbon military procurement, R&D, and a new network of university-private sector innovation hubs to create an "energy revolution."
This sensible proposal predictably drew fire from committed "alarmists" and "deniers." But, promisingly - and surprisingly, given the somewhat toxic state of US politics - it attracted broad support and intelligent commentary from many mainstream pundits.
Adding to the swell of voices, this month will see the documentary film based on Cool It, released in the US.
It is too early to suggest that politicians might make real progress toward implementing genuinely effective policies on climate change. But, given the dearth of common sense in recent years, the mere fact that a growing chorus of reasonable voices can now be heard is nothing short of miraculous.
Bjørn Lomborg is the author of The Skeptical Environmentalist and Cool It, subject of the film Cool It, the director of the Copenhagen Consensus Center, and adjunct professor at Copenhagen Business School ©Project Syndicate