One more look, this time in greater detail, at that bogus global warming “pause” you’re going to be hearing so much about shortly.
My guess is that Chuck Todd will be one of those bringing the non-story to you, because … well … Chuck Todd. But hey, watch the Sunday shows as well; they’ll all be hammering the soon-to-be-released fifth assessment report (AR5) from the United Nations Intergovernmental Panel on Climate Change (IPCC), which is due out momentarily. The mainstream media will be denier central (“on the one hand, on the other hand”) for as long as the report is news, and as long they’re paid by climate-denying corporations to report it.
We talked about why the “pause” is bogus, and presented a global heating chart — what heat gets absorbed where — as evidence. But I didn’t explain the dynamic, so here it is. You’ll want to know this for your denier friends. It’s not that hard to learn or say, though it may be hard for them to listen to.
(By the way, there’s a great global warming primer here — all the basics in one readable place. Want a definition of the “greenhouse effect”? Click through.)
Heat absorbed by the upper ocean both rises and falls. Rates of each vary over time.
Bottom line first, and that’s your bottom line, ahead of the detailed explanation. When the upper ocean absorbs heat, it distributes it both up and down. Rates of each vary. So if upper ocean heat falls to lower ocean layers more rapidly than it rises into the air, the upper ocean will remain relatively cool, and it will not heat the air as quickly. For a time.
Nevertheless, the total heat absorbed by the system is still increasing, and at a very rapid rate. At some point, those upper ocean and surface temperatures will shoot up again.
Some “pause.” You ate the monster meal; you just haven’t thrown up yet. (Yes, that’s a reference to the “wafer-thin mint,” and no, I won’t link to it. Sorry.)
Actually the only pause the deniers really care about is a pause in their paychecks from denier-suppliers like the Heartland Institute. As in, they only care that there never be such a pause.
I offered this chart previously, which shows the increase in total-system temperature, but doesn’t easily show the rate of growth of the system’s components.
Look carefully at the labels for the two ocean components, 0–700 meters and 700–2000 meters. On other charts the groupings will differ slightly. The “pause” you’ll be hearing about is the slowing of the rise of the light blue area (shallow ocean temperature), added to the small rise in the red area, relative to itself only. No “pause” chart I’ve seen takes the dark-blue area (deep ocean temperature) into account.
Here’s more from Real Science (my emphasis). The first chart they present, showing shallow ocean temperatures only, is the kind the “pause” deniers use. You’ll see it a lot if you fish these waters in your reading.
Slowdown in the upper ocean
Let us look at the upper ocean (for historic reasons defined as the upper 700 m):
And here is the direct comparison since 1980:
We see two very interesting things.
First: Roughly two thirds of the warming since 1980 occurred in the upper ocean. The heat content of the upper layer has gone up twice as much as in the lower layer (700 – 2000 m). The average temperature of the upper layer has increased more than three times as much as the lower (because the upper layer is only 700 m thick, and the lower one 1300 m). That is not surprising, as after all the ocean is heated from above and it takes time for the heat to penetrate deeper.
Second: In the last ten years the upper layer has warmed more slowly than before. In spite of this the temperature still is changing as rapidly there as in the lower layer. This recent slower warming in the upper ocean is closely related to the slower warming of the global surface temperature, because the temperature of the overlaying atmosphere is strongly coupled to the temperature of the ocean surface.That the heat absorption of the ocean as a whole (at least to 2000 m) has not significantly slowed makes it clear that the reduced warming of the upper layer is not (at least not much) due to decreasing heating from above, but rather mostly due to greater heat loss to lower down: through the 700 m level, from the upper to the lower layer.
Pretty clear. At the moment, the heat absorbed by the upper ocean is going down faster than it’s going up — at the moment. That will change. And again, the entire system is still absorbing more heat than it’s giving off. Global warming.
The authors conclude:
There are then at least three independent lines of evidence that confirm we are not dealing with a slowdown in the global warming trend, but rather with progressive global warming with superimposed natural variability:
1. Our correlation analysis between global temperature and the El Niño Index.
2. The measurements of oceanic heat uptake.
3. The new model calculation of Kosaka and Xie.
There’s more in this good report. Please read if you wish.
Michael Mann on the same subject
Here’s a recent op-ed by Dr. Michael Mann, author of the famous Hockey Stick diagram, which in part addresses the same subject (again, emphasis mine):
In many respects, the IPCC has been overly conservative in its assessment of the science. The new report, for example, slightly reduces the lower end of the estimated uncertainty range for a quantity know as the equilibrium climate sensitivity — the amount of warming scientists expect in response to a doubling of carbon dioxide (CO2) concentrations relative to preindustrial levels (concentrations that will be seen mid-century, given business-as-usual emissions).
The IPCC reports a likely range of 1.5 to 4.5 degrees Celsius (roughly 3 to 8 degrees Fahrenheit) for this quantity, the lower end having been dropped from 2.0 degrees C in the fourth IPCC assessment. The lowering is based on one narrow line of evidence: the slowing of surface warming during the past decade.
Yet there are numerous explanations of the slowing of [surface] warming (unaccounted for effects of volcanic eruptions and natural variability in the amount of heat buried in the ocean) that do not imply a lower sensitivity of the climate to greenhouse gases.
A second source, and again, seems pretty clear.
“No misrepresentation is too egregious for professional climate-change deniers”
About the deniers, Mann says:
The lesson here, perhaps, is that no misrepresentation or smear is too egregious for professional climate-change deniers. No doubt, we will continue to see misdirection, cherry-picking, half truths and outright falsehoods from them in the months ahead as the various IPCC working groups report their conclusions.
Note — “professional climate-change deniers”. They are indeed a profession, and a well-paid one. Last I heard, the Koch Bros were loaded, rolling in it, and eager to spend to get at their unmonetized carbon assets. If you’re conscienceless, they have a job for you. So do all of these good folks.
Don’t be fooled by the smoke and mirrors and the Rube Goldberg contraptions. The true take-home message of the latest IPCC report is crystal clear: Climate change is real and caused by humans, and it continues unabated. We will see far more dangerous and potentially irreversible impacts in the decades ahead if we do not choose to reduce global carbon emissions. There has never been a greater urgency to act than there is now.
The latest IPCC report is simply an exclamation mark on that already-clear conclusion.
To illustrate his urgency, here’s the U.S. at 1000 ppm of CO2, showing weeks per year of temperatures greater than 100°F. Check out the California Central Valley; last I heard, agriculture was important there:
I’m eagerly waiting for that report. Stay tuned.
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