Jim Manzi takes issue with Juliet Eilperin's recent coverage of new studies that indicate the world would need to stop emitting carbon altogether within the next few decades to avert dangerous levels of climate change. According to Manzi, the question isn't, "What if we don’t want the Earth to warm anymore?" as Eilperin quotes Carnegie Institution senior scientist Ken Caldeira, co-author of one of the studies, as asking. Rather, he says, we should ask "What are the costs versus benefits of reducing emissions to avoid warming?" His argument:
What's so funny is that Eilperin never seems to be willing do the work to pick up the trail of breadcrumbs that all her interviewees leave behind them. She writes that "Most scientists warn that a temperature rise of 2 degrees Celsius (3.6 degrees Fahrenheit) could have serious consequences." Really -- how serious? Well, according to the U.N. IPCC a 4C increase -- twice this amount -- would reduce global economic output by 1 to 5 percent. Oh yeah, that's in the world of the 22nd century which is expected to have per capita consumption of something like $40,000 per year versus our current consumption of about $6,600 per year. So we are condemning future generations to be only 5.7 times richer than us, rather than 6 times richer.
Of course, it's hard to know how much global warming will affect the quality of life for future generations, not just in a generation or two, but in 10 or 20. While it might not decrease consumption rates to a particularly great extent in the foreseeable future, there are plenty of other "serious consequences" of not preventing warming. This is not a sound reason to spurn carbon caps. Most scientists understand that even a temperature rise of a few degrees would have serious effects in terms of precipitation patterns, water resources, oceans, and weather patterns. If we don't limit emissions and we continue to consume at current rates, the world will, at some point, become inhospitable for future generations.
Manzi's line of reasoning is particularly problematic when you take into account the wealth distribution factor. Clearly, temperature rises will not affect the rich as much or as soon as it will the poor, on both a national and individual level. As Nicholas Stern argued in his report on the economics of climate change, a fair and accurate assessment of the costs of climate change must include an analysis of the costs to all stakeholders. To put it more concretely, we can't really measure the loss of an entire small island nation in terms of the amount that its loss would take away from the total world GDP -- there are simply other factors to consider.
--Kate Sheppard
