A decision to exit the Paris Accords is no mere gesture. The central fact for citizens everywhere is that putative “climate solutions” would deploy trillions of dollars and implement mandates and diktats for the supply and use of energy in every aspect of society.
The stated rationale for proposals to alter completely how civilization is fueled is the need for an “insurance policy” against future climate catastrophes. In that framing, the climate-fearful argue that some possibility of consequential future harms warrants the “responsible” decision to “buy” insurance now. But this often-argued “insurance” construct assumes that we know enough to say that the consequences of future climate change justify paying for the insurance—and collaterally, that we know the “insurance” itself will be affordable.
It turns out that we do know quite a bit about both those domains. As we outline below, reality tells us that the climate-change consequences that we’re trying to avoid will be modest—and that the costs of the “insurance” are staggering.
What are we insuring against?
The proposition of paying for “climate insurance” requires that we first consider the “benefits” of 50-year decarbonization, a timescale that comes from the Paris goal of limiting global average temperature rise to 2oC. We can then turn to weighing those benefits against the cost of achieving so-called “net zero” greenhouse gas emissions. That comparison is complicated, not least because of the uncertainties on the impacts allegedly avoided by reducing human influences on the climate. There’s also the issue of “costs and benefits to whom,” as well as the question of whether there is in fact urgency to reduce emissions.
There are three points to make: the timescale for emissions reduction is arbitrary; the climate “threat” is far from dire; and the cost/benefit calculus very much depends on who is doing the calculation.
Start with the Paris goal itself, which seeks to keep the rise in average global surface temperature to less than 2oC, which the climate modelers say would require net zero global emissions in the latter half of this century. Meanwhile, emissions are continuing to rise and will again reach an all-time high this year. The subtitles of the UN’s annual Emission Gap Report give a flavor of the lack of progress: in 2023 it was a “Broken record . . . Temperatures hit new highs, yet world fails to cut emissions (again)”, and this year it was “No more hot air, please.” But even that 2oC is not a hard limit. When Hans Schellnhuber, the so-called “father of the two-degree limit,” was once asked why he gave that number, he responded that it was about right, and it was an easy number for politicians to remember. There is no credible case to make that all manner of chaos will suddenly break out if the temperature rises two, or even three, degrees.
Next is the question of whether the climate threat is so dire that it requires precipitous and Promethean actions—transforming the entire world’s energy system in a few decades. The answer to that question is not as uncertain as the doomsayers claim. There is some guidance from recent history, since the globe has warmed 1.3oC in the past 120 years and about the same amount of warming is expected over the next century. Rather than catastrophe, humanity has seen unprecedented prosperity over that period: the global average lifespan has gone from 32 years to 72 years, per capita GDP has increased sevenfold, the literacy rate has soared, and the death rate from extreme weather events has decreased by a factor of 50!
So, it’s hard to believe that a comparable warming over the next century will significantly derail such progress. In fact, the consensus of economic impact studies, as published last year by the Biden White House, is that there would be a few-percent decrement in the GDP for a few degrees of warming. That’s “in the noise,” as we physicists say. Of course, there will be differential impacts, there are uncertainties, and GDP isn’t the only measure of wellbeing. Nevertheless, predictions of catastrophe are not credible.
If you listen to the popular media, you might believe that we humans have already broken the climate. Yet even the Intergovernmental Panel on Climate Change (IPCC) can’t find any climatically significant trends in most climate impact drivers, let alone attribute them to human influences. Losses from extreme weather events are in fact declining as a percentage of GDP as the world becomes more resilient. And projections of the magnitude of future warming have decreased as the IPCC refines its models and the world emits somewhat less CO2 than had been expected because of both slower growth and a shift to carbon-light energy sources.
No comments:
Post a Comment