It's George Will's brain that is melting away
George Will's recent column, entitled "With a closer look, certainty about the
‘existential’ climate threat melts away," is a genuine
disappointment. It's a parade of non sequiturs and stillborn logic that
demonstrates Will has little comprehension of his material, nor capacity to
reason about it.
Will begins his titillation of the skeptical brain (I know some of those brains!) with the strained implication that media reporting on climate science is overwrought. Thus, Will writes:
Last year, CNN announced: “Oceans are warming at the same rate as if five Hiroshima bombs were dropped in every second.” True. However: “The earth absorbs sunlight (and radiates an equal amount of heat energy) equivalent to two thousand Hiroshima bombs per second.” That sentence is from “Unsettled: What Climate Science Tells Us, What It Doesn’t, and Why It Matters,” by physicist Steven E. Koonin.
However? Will must imagine that the large magnitude difference between incoming solar radiation striking the earth, and the increment of it stored in the oceans, means that ocean heating isn't significant. That is nonsense.
Like all radiating bodies, the earth seeks thermal equilibrium, and achieves it by (eventually) radiating as much energy (as heat) outward into space as it receives (as visible and ultraviolet light) from the sun. I say "eventually" because at present incoming and outgoing radiation are not completely in balance[*], due to the effect of increased (and increasing) greenhouse gasses in the atmosphere.
Greenhouse gasses absorb some fraction of outgoing infrared (heat) radiation and then re-radiate it in all directions. Some of it is directed back to earth, where it is re-absorbed. Conceptually, the earth "wants" to radiate as much energy out to space as it receives from the sun, but is presently unable to do so because of increased concentrations of greenhouse gasses, which ensure that not all the radiated heat makes it through the atmosphere.
The solution is the
most basic of physics: The planet warms until incoming and outgoing
energy are in balance at a higher equilibrium temperature. Planetary
warming achieves equilibrium because bodies radiate heat in proportion
to their temperature, so a warmer body radiates more heat than a cooler
one. A warmer earth radiates more heat, so more of it gets through the atmosphere and thus energy balance is restored. The composition of the atmosphere determines what that ultimate
equilibrium temperature will be.
It's the planetary warming now occurring, as the earth seeks energy balance, that is so concerning. A lot of excess heat—the difference between incoming and outgoing radiation—is stored in the oceans, causing them to warm significantly. At present a good bit less (but not insignificant) amount of heat is also stored on land: a ratio that's expected to change as the oceans approach their capacity to absorb ever more heat, while land temperatures increase.
Remember: When the earth is in thermal equilibrium, the amount of solar radiation striking the planet is exactly equal in energy to the amount of heat radiated outward into space—whatever those magnitudes may be. That some energy is being retained in the warming oceans is an indication that the earth isn't in thermal equilibrium, and as a matter of physics the only thing that can happen is for the earth to get warmer.
What quantity of heat is being retained by the oceans? According to Will and (presumably) CNN, it's equivalent to 5 Hiroshima bombs per second. George Will apparently thinks that's not much, for no better reason than it's a lot less than the total amount of incoming solar radiation. And that is not a reason at all.
This is the kind of "stillborn logic"[†] I mentioned above. Another specious observation from Will is that sea levels "have been rising for 20,000 years." Which is an exceedingly curious time frame to mention.
Think, please, about what was happening 20,000 year ago. That was the period of the last "glacial maximum" or, if you prefer, the peak of the most recent "ice age." Ice sheets up to 2 miles thick covered much of Canada and some of the United States. Because so much water was locked up in land-based ice, sea levels were hundreds of feet lower than today. You have no doubt heard of the "Bering land bridge" across which humans (who became the original native Americans) are presumed to have walked into North America from Siberia, when sea levels were so low.
As the ice age ended and glaciers melted, sea levels rose rapidly. What else could they do? So of course if you choose your interval to begin with the most recent glacial maximum, it is trivially true to say that sea levels have been rising over that interval.
Up to around 8,000 years ago, the rate of rise was enormous. Later the curve flattened and sea levels stabilized. Except for very recently, they've been largely stable for the entire period of human civilization. Some experts contend that the long period of both sea level and temperature stability played a profound role in allowing human civilization to take hold and flourish. The two certainly coincide.
Source: https://en.wikipedia.org/wiki/Past_sea_level |
The implication of George Will's misleading framing that sea levels "have been rising for 20,000
years" is that the current rise is just a continuation of a very long trend. The correct (and intellectually honest) account is that sea levels rose dramatically with the end of the most recent ice age, but have been stable for the entire period of human civilization. The rise happening now is a new phenomenon.
According to NASA, "from about 3,000 years ago to about 100 years ago, sea levels
naturally rose and declined slightly, with little change in the overall
trend." But sea levels have resumed their rise over the past century as
the global climate has warmed. The total rise over a century has been around 6 to 8
inches, with, according to NASA, half of that occurring since 1993. So
the rate of rise is accelerating and, says NASA, is "unprecedented over
the past several millennia." The acceleration, happening now, will continue in coming decades.
Even that 6 to 8 inches is not nothing.
It accounts for the dramatic increase in what's called "sunny day flooding," where at high tide water comes up through the ground to flood
streets in certain coastal areas such as the Chesapeake and Miami regions. Those several inches add an additional height increment to hurricane storm surge,
and were the difference that caused New York subway tunnels to flood,
for the first time ever, during Hurricane Sandy.
But that 6 to 8
inches is barely the beginning. Scientists say we could easily see
an additional 2 feet of rise by the end of this century, and potentially
a good bit more.[‡] And that, too, could be just the beginning. The
disintegration of the Antarctic ice sheets could add hundreds of
additional feet over the coming centuries. All of it—the 6 to 8
inches, and the several feet, and the several hundred feet—all of it
is caused by human activity. This is a novel situation: human civilization has never previously experienced such sea level instability, George Will's very misleading claim notwithstanding.
George
Will makes the obligatory and meaningless observation that the earth's
climate has always been changing over its 4.5 billion year history. The landscape of climate skepticism and denialism and don't-care-ism is littered with such intellectual inanity. The
germane point is that current warming is overwhelmingly a result of
human activity, and it is proceeding far more rapidly than any "natural"
climate change event would ever occur, including the transition into or out of an ice age. And it will be as horrifically destructive as it was avoidable. Whatever has happened in the geologic past, this one's on us.
George Will chooses his statistics carefully to inform us that "the average warmest temperature across the United States has hardly changed since 1960 and is about what it was in 1900"—a statistic which is utterly meaningless to readers without definition. [my italics -mb] Average over what interval? What does "across the United States" mean?
Meanwhile, the average annual temperature across the contiguous United States has risen between 1.2 and 1.8°F since the beginning of the 20th century. Being an annual average, this includes all temperatures at all seasons at all measuring stations, and obviously indicates that, overall and on average, the climate is warming. That rise might not sound like much, but seemingly small increases in average annual temperature dramatically drive up the incidence of extreme events—events such as the historic heatwave in the Pacific Northwest in 2021, when Portland, Oregon, hit 116°F on June 26, and Seattle hit 108 on June 28. Lytton, British Columbia, exceeded 121°F on June 29, the highest temperature ever recorded in Canada. These are Death Valley temperatures in the normally mild Pacific Northwest, where air conditioning is uncommon. Hundreds (for whom the heatwave was undeniably an "existential" event) died as a consequence.
Scientists who specialize in climate attribution say such events would have been impossible but for anthropogenic climate change, and that as the average annual temperature rises, heatwaves will become more frequent, longer, and more deadly. [Update, August 2022: Epic heatwaves have ravaged many regions of the earth this summer, including, again, in the Pacific Northwest.] Scientists warn that warming of 2.0°C (3.6°F) above the 20th century average will have far more severe consequences than would warming of 1.5°C (2.7°F).
The most recent year, 2020, was 2.4°F above the 20th century average in the U.S. The five warmest years on record in the U.S. have all occurred since 2012. The U.S. trend is as unmistakable as the global one, and the barrage of recent extreme weather events (fires, flooding, heat, drought) highlights the existential nature of what is unfolding. As always, we are just getting started.
The National Oceanic and Atmospheric Administration recently released its decadal update (based on 1991-2020 data) of climate "normals" for the U.S. and, by George, the new normals are warmer than the previous normals published 10 years ago. (By definition, "normal" is based on the most recent three decades of temperature data, and is officially updated every 10 years.)
NOAA tells us that, yes indeed, global warming is driving normal temperatures ever higher. "The influence of long-term global warming is obvious," NOAA says. And so it is, as this NOAA graphic makes clear. (Click on image for a larger view.)
Source: https://tinyurl.com/3nuxet36 |
Precious column space is used up by more non sequiturs from George Will, such as complaining about the director-general of the World Health Organization asserting that climate change causes deadly indoor air pollution. George Will calls that "scandalous;" I call it an irrelevant red herring.
So what is George Will trying to communicate? He actually admits the climate is changing, that human activities account for almost all the increased atmospheric carbon dioxide, that carbon emissions affect the climate, and that "the effects should be mitigated by incentives for behavioral changes and by physical adaptations." And yet, he implies, it's all still so uncertain, and science can't disentangle all the complications, and China, and India, and ....
Yet as the latest IPCC assessment (just released) indicates, the science has never been more definitive. That report, the sixth major assessment since 1991, is a gut punch to the world's future prospects, and a final call to action that must be accomplished on an enormous scale in hardly any time. As thousands of climate scientists are telling us unambiguously, the future is now.
But George Will needs to retain some measure of ambivalence, some measure of uncertainty, for reasons only he could explain. That he consistently reasons so poorly on the subject suggests he's grasping at thin reeds, perhaps to convince himself, and us, that what's happening isn't happening, or that it's really not so bad, or that we don't yet know if it will be bad. Spoiler alert: It will be bad.
Perhaps George Will's motivation is ideological: global warming represents an enormous failure of the free markets that he worships, and requires the massive intervention of the governments that he abhors. That government might need to intervene strongly in the economy to achieve the necessary decarbonization at the necessary pace is probably more than George Will can bear. (But don't fret: the economy will thank us. Our long term economic prospects will be stronger in an energy economy based on carbon-free non-polluting renewables.) Thus George Will's recommendation to incentivize "behavioral changes" as a tepid and bizarrely inadequate response, and also "adaptation," for which there are plenty of options for the wealthy and privileged, but for the rest of humanity, not so much. (If by "incentivize" George Will means a comprehensive and meaningfully stiff carbon tax, then I withdraw my complaint.)
Here is my point. If George Will had a case to make about the uncertainty of the "existential" climate threat, he would make it. That his facile attempt descends immediately into inanity and illogic is a good indication that he doesn't have a case.
*Footnote: George Will's statement that "The earth
absorbs sunlight (and radiates an equal amount of heat energy)" is demonstrably false. It is true that incoming and outgoing radiation would be equal if the earth were in thermal equilibrium, but the whole point of global warming is that it is not. You can see this easily enough by observing that even George Will agrees that some energy (5 Hiroshima bombs per second worth, he says) is being stored in the oceans. That energy has to come from somewhere. It can only come from the sun: there is no other energy source that meaningfully affects the temperature of the planet. (No, energy in the earth's core has no material effect.) Thus, whatever is being stored in the oceans and on the land must be subtracted from incoming radiation in order to determine outgoing radiation. The earth is not at present radiating "an equal amount of heat energy" as Will claims.
Were atmospheric carbon dioxide concentration to at some point stop increasing, then the earth would eventually reach thermal equilibrium (at a temperature determined by that concentration), and then incoming and outgoing radiation would be in balance.
†Footnote: The inability to reason about climate is frequently appalling. For example, you sometimes hear it said that, since volcanoes emit more carbon dioxide than humans, then humans aren't causing climate change. The emissions claim is itself false, but in some ways the breakdown of logic is even worse. Any thinking person ought to be able to reason his way through this, with no need to know anything at all about the relative emissions of humans and volcanoes. If the climate is stable without human emissions, but warms with them, then humans are the cause of the warming, regardless of what volcanoes emit. Similarly, if the amount of energy absorbed by the oceans is causing them to get hotter, then it doesn't matter that the magnitude of incoming solar radiation is a lot greater than what the oceans are absorbing.
‡Footnote: From the graph above, you can see that the roughly 6,000 years over which the most rapid sea level rise occurred averaged around 13.3mm of rise per year, which is 1,333mm—around 52 inches, or 4.3 feet—per century. But that was a consequence of the strong initial pulse of meltwater from thawing glaciers coming out of the ice age. The projected range of sea level rise over this century is at least 12 inches on a best-case low emissions pathway (a pathway we're not presently on), and up to 8 feet on the worst-case high emissions pathway. Whatever pathway we eventually choose, it is clear that the graph's curve will bend sharply upward, away from the stability we've enjoyed for millennia. It's well within humanity's ability to exceed the highest rates of sea level rise seen over the past 20,000 years, despite that previous extremely rapid rise being a result of the melting of massive amounts of land ice in the northern hemisphere. The point is that even if the world responds with urgency and determination, we will still see at least a foot of sea level rise by the end of this century, and a good bit more if we don't. Our position in the present is one of looking forward, considering the possibilities, and deciding what we will do. Literally everything hinges on that choice. That's why the climate threat is said to be "existential."
Copyright (C) 2021 James Michael Brennan, All Rights Reserved
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