Time for more climate change whiplash

This article in Nature News:  Can the world kick its fossil fuel addiction fast enough is another in the long line of "climate change whiplash" reporting we've been seeing for a few years.  On the one hand, emissions are clearly still going up when the economy picks up; on the other, past estimates of the decreasing cost and increasing deployment of renewable energy were clearly underestimates, and a lot of renewable energy deployment is in the pipeline.

As to whether market based policy is going to work fast enough, there seems to be increasing doubt:

But politics can also help to bring about rapid change. While Trump is fighting on behalf of the fossil-fuel industry, leaders of other countries are moving in the opposite direction. The United Kingdom and France have both announced plans to ban the sale of petrol- and diesel-powered vehicles by 2040. And more than two dozen countries have committed to phasing out coal by as early as 2030.

These types of mandate are a sign that energy politics might be shifting towards more brute-force methods, says Michael Mehling, an energy and environmental-policy researcher at the Massachusetts Institute of Technology in Cambridge. Economists tend to favour market-based programmes, such as the EU’s Emissions Trading System, but Mehling says there is little evidence that such arrangements will drive the kind of rapid transformational change needed to meet global climate goals. Old-school government mandates might be the last resort, Mehling says. “If the decisions are made at a sufficiently high level,” he says, “they can change the landscape pretty much overnight”.

In any case, as I've been posting for some time, it's not as if those who are supposed to be the Right wing proponents of small government and free market solutions (libertarians and so called "classical liberals") are actually interested in addressing climate change at all:  they are more interested in corporations making money now, and a gormless in principle belief that governments never doing anything is better than governments doing something, such that they will clasp any reason (ranging from entertaining outright denialists to a "it's too late now anyway" defeatism) so as to justify not endorsing any policy action.   They are worse than useless, and just need to be bypassed.  

And to be fair, the Left of politics needs to be criticised for a certain gullibility in the policies and advice they have promoted, too.   At least they are interested in solutions, which is the first step in the process.

But look at the revision now going on regarding the estimates of the social cost of climate change, just in the matter of agriculture.  From this paper's abstract:

Despite substantial advances in climate change impact research in recent years, the scientific basis for damage functions in economic models used to calculate the social cost of carbon (SCC) is either undocumented, difficult to trace, or based on a small number of dated studies. Here we present new damage functions based on the current scientific literature and introduce these into an integrated assessment model (IAM) in order to estimate a new SCC. We focus on the agricultural sector, use two methods for determining the yield impacts of warming, and the GTAP CGE model to calculate the economic consequences of yield shocks. These new damage functions reveal far more adverse agricultural impacts than currently represented in IAMs. Impacts in the agriculture increase from net benefits of $2.7 ton⁻¹ CO₂ to net costs of $8.5 ton⁻¹, leading the total SCC to more than double.

That's some massive change to an input into an IAM, isn't it?

And further to my skepticism that IAMs could have adequately worked out the cost of intense rainfall and sea level rise, I note from a review of a new book on the latter (my bold):

Projections diverge on how fast the inundation will proceed if nations stay on a “business as usual” path in their greenhouse gas emissions. The most recent report from the Intergovernmental Panel on Climate Change projects a maximum of about three feet by the year 2100; James Hansen and colleagues project several times that much over the same time frame; a recent research paper that recalculates the dissolution of Antarctic ice warns of five feet as a median estimate. Sea level rise on such a scale would submerge an area inhabited, just now, by 153 million people. For an indefinite number of decades or centuries after that, the rise would continue.

As former presidential science advisor John Holdren once pointed out, human beings have three options: reduce the amount of climate disruption they are causing, adapt as intelligently as possible to the change they can’t avoid, and suffer. “The question – the issue that’s up for grabs – is what the mix going forward is going to be,” Holdren has said.

Under a “work and hope” scenario – one in which the world cuts emissions with extreme speed and hopes that the more optimistic climate change projections are the accurate ones – sea level rise might be limited to something like two feet. But even that more modest figure would imply worldwide consequences exceeding our ability to comprehend them. “Staggering,” “catastrophic,” and other alarm words have lost much of their voltage. In these busy times, “trillions” are the new “millions” – and thus rather negligible. But two feet of sea level rise is, beyond question, coming.

So, have IAMs been worked out on the "best case" scenario of 2 feet by 2100, when it may be 2 1/2 times  that, and causing the re-location of 153 million people? 

But, again, why should this be taken as a licence to do nothing in terms of CO2 reduction?   Even if it takes 200 to 300 years (instead of 100 years) of increase to reach a 3 metre sea level rise, slowing down the rate surely buys time for (some) cities to respond.  

It's about time I revisited the matter of ocean acidification too.  That is a key area that, I believe, is not realistically amenable to to geoengineering, regardless of what techno-optimists may think can be done temperature wise.