The summer's heat wave with its scores of victims grimly reminded us that our emission of greenhouse gases is making the planet unlivable. While science is telling us that we should be paying attention to the carbon budget, the two main political parties in Quebec – the CAQ and the PLQ – persist in their obsession with fiscal budgets. As for the PQ and QS, both recently unveiled climate plans. I'de like to take a look at these from the point of view of climate science.
The temperature has risen by 1C, mainly due to CO emitted by fossil fuels. According to climate projections, continuing on a business as usual path will push the temperature 4.5 or more degrees above preindustrial level (Intergovernmental Panel on Climate Change, 2013). In 2010, the international community finally agreed to limit the increase to 2C and in 2015, 196 countries signed the Paris agreement that recommended a safer 1.5C limit. Nevertheless, the countries' promises were so weak that even if they are respected, the temperature will still exceed the very dangerous 3C threshold. Since Paris, rather than decreasing towards zero, global emissions have continued to climb (+1.4% in 2017).
For all practical purposes, there are no natural processes that reduce CO concentrations. We therefore have a carbon budget that we must share with future generations. In order to have a good chance of respecting the 2C threshold, we must limit our future emissions to 550 billion tons of CO This is the equivalent of 10 per cent of the fossil fuel reserves held by the fossil fuel companies and at our current emission rate, the budget will be exceeded in 16 years (in only eight years for the safer 1.5C threshold). This is why it is urgent that governments respect not only fiscal, but also carbon budgets. Although the Parti Quebecois has just proposed a refreshing "green turn" only Quebec Solidaire's plan fully recognizes the fundamental role of the carbon budget by integrating it into their plan.
The challenge of decarbonising the economy – the energy transition – is immense. Since 1990 Quebec's emissions have reduced by nine per cent, but to attain the target of 95 per cent reduction in 2050 needed to respect the 2C threshold, we'll need to make the same nine per cent reduction every year for the next 32 years.  In comparison, Quebec's current "action plan" proposes a reduction of 3.1 per cent per year to reach a 37.5 per cent reduction in 2030. In the meantime, according to various studies, Quebec is set to miss its 2020 target.
The only way to increase the carbon budget is via the deployment of "negative emission" technologies that remove CO from the atmosphere. The most promising is bio-energy carbon capture and storage: the burning of biomass and the capture of the emitted carbon. Typical scenarios propose that areas one or two times the size of India be planted with trees or other biomass. The plants will then be regularly harvested and burned in special power plants that capture the CO and bury it for millenia. Although the viability of negative emission technologies is highly speculative, they would in principle compensate for positive emissions, allowing economists to be falsely reassure policy makers. In the jargon of the business, basing climate salvation on negative emissions constitutes a "moral hazard."
A transformation to a green economy requires much more radical measures: the advent of green capitalism is a chimera.
We have no choice but to launch the transition. One of the necessary tools – and the only one compatible with neoliberal economics — is to put a price on carbon, the "polluter pays" principle. For the moment, the Quebec government is betting on its cap-and-trade system that makes us all pay for the development of green technologies — in California! Fortunately other choices are possible. Several "fee" and "dividend" systems have been proposed that primarily tax the rich, and have a significant potential for wealth redistribution. The money generated by the carbon fee would be directly redistributed as "dividends" so as to benefit low income groups.
Over the last 40 years, the prophets of neoliberalism have preached the virtues of free markets and the liberty of capital to maximize its profits; they find a price on carbon repugnant. However a transformation to a green economy requires much more radical measures: the advent of green capitalism is a chimera. On the contrary, this immense transition requires disciplining the market, democratic control and economic planning.
 This budget is for a 66% chance of remaining below the threshold. The numbers are an update from those in: Anderson, K. Duality in climate science. Nature geoscience 8, 898-900 (2015). See the figure for a graphical extrapolation based on 2016 data. The current 1.5C budget is about half the 2C budget and the number of years is calculated based on our current global annual emission of 32.5 billion tons of CO, from ref. (2). See also Anderson, K. & Peters, G. The trouble with negative emissions Reliance on negative-emission concepts locks in humankind's carbon addiction. Science 354, 181-182 (2016).
 The 1.5C budget is about half the 2C budget and the number of years is calculated based on our current global annual emission of 32.5 billion tons of CO, from ref. 5. See also Anderson, K. & Peters, G. The trouble with negative emissions Reliance on negative-emission concepts locks in humankind's carbon addiction. Science 354, 181-182 (2016).
Also on HuffPost: