Costos

Qué horror, un estudio sobre un aspecto muy poco políticamente correcto del “cambio climático, el costo:

Nordhaus and his colleagues have developed a small but comprehensive model that combines interactions between the economy and climate called DICE-2007, short for Dynamic Integrated model of Climate and the Economy. Nordhaus first computes a baseline that assumes that humanity does essentially nothing to limit its output of carbon dioxide. By 2100 CO2 atmospheric concentrations would rise from the pre-industrial level 280 parts per million (ppm), to 380 ppm today, to 685 ppm in 2100. Global average temperature would rise by 2.4 degrees Celsius by 2100. In this baseline scenario, the DICE-2007 model estimates that the present value of climatic damages is $22.6 trillion. DICE-2007 includes damage to major sectors such as agriculture, sea-level rise, health, and non-market damages.

Nordhaus then uses his model to assess the ambitious CO2 reduction proposals made by British economist Nicholas Stern and former Vice President Al Gore. Nordhaus calculates that the Stern and Gore proposals for steep immediate emissions reductions produce very similar cost/benefit results. Nordhaus also evaluates explicit temperature and concentration goals, e.g., limiting average temperatures to 1.5 degrees Celsius above current levels or greenhouse gas concentrations to no more than 1.5-times pre-industrial CO2 atmospheric concentrations.

So what did Nordhaus find? First, the Stern proposal for rapid deep cuts in greenhouse gas emissions would reduce the future damage from global warming by $13 trillion, but at a cost of $27 trillion dollars. That's not a good deal. For an even worse deal, the DICE-2007 model estimates that the Gore proposal would reduce climate change damages by $12 trillion, but at a cost of nearly $34 trillion. As Nordhaus notes, both proposals imply carbon taxes rising to around $300 per ton carbon in the next two decades, and to the $600-$800 per ton range by 2050. A $700 carbon tax would increase the price of coal-fired electricity in the U.S. by about 150 percent, and would impose a tax bill of $1.2 trillion on the U.S. economy.

In addition, scenarios which attempt to keep the future average temperature increase below 1.5 degrees Celsius and concentrations below 1.5-times pre-industrial atmospheric concentrations are also not cost-effective. The DICE-2007 model calculates that both would cost more than $27 trillion in abatement costs and provide only about $13 trillion in reduced damages.