If it is so hard to change the climate to suit humans, why not alter humans to suit the changing climate, philosophers from Oxford and New York universities are asking.
They suggest humans could be modified to be smaller, dislike eating meat, have fewer children and be more willing to co-operate with social goals.
Behavioural changes might not be enough to prevent climate change even if they were widely adopted, and international agreements for measures such as emissions trading are proving elusive, say Matthew Liao of New York University and Anders Sandberg and Rebecca Roache of Oxford University.
So human engineering deserves serious consideration in the debate about how to solve climate change, they write in a coming paper for the academic journal Ethics, Policy & Environment.
A person's ecological footprint is directly correlated to size, because larger people eat more than lighter people, their cars need more fuel to carry them and they wear out shoes, carpets and furniture sooner than lighter people, the authors write. They suggest hormone treatments could be used to suppress child growth, or embryos could be selected for smaller size.
Reducing consumption of red meat could have significant environmental benefits, the paper says, citing estimates that as much as 51 per cent of the world's greenhouse gas emissions come from livestock farming. They say people who lack the motivation or willpower to give up eating meat could be helped by ''meat patches'' on their skin to deliver hormones to stimulate their immune system against common bovine proteins.
''Eating 'eco-unfriendly' food would induce unpleasant experiences,'' the authors say.
Better educated women have fewer children, so human engineering to improve cognition could reduce fertility as ''a positive side effect from the point of view of tackling climate change'', the paper argues.
Pharmacological treatments such as the ''love drug'' oxytocin could encourage people to act as a group and boost their appreciation of other life forms and nature, the authors say.
The paper has sparked a storm in the blogosphere. The environmentalist Bill McKibben tweeted that the authors had proposed ''the worst climate-change solutions of all time''. They have also been denounced as Nazis and ecofascists.
The authors are bemused but unrepentant. If people were willing to consider ''really dangerous'' geoengineering solutions such as using space mirrors to alter the Earth's solar reflectivity, human engineering should also be on the table, Dr Liao said.
''At least the human engineering solutions we have described rely on tried and tested technology, whose risks, at least at the individual level, are comparatively low and well known.''
The authors emphasise they are not advocating human engineering be adopted, only that it be considered. They also envisage it as a voluntary activity possibly supported by incentives such as tax breaks or sponsored healthcare, not something coerced or mandatory.
Dr Sandberg, of the Future of Humanity Institute at Oxford University, said the paper had inadvertently ''managed to press two hot buttons'' - climate change and ''messing with human nature''. He predicted the paper would mutate into a story that scientists were working on re-engineering people to be green and it would be adopted as ''yet another piece of evidence of the Big Conspiracy''.