Guest Post by Willis Eschenbach
In my last post, “Emergent Climate Phenomena“, I gave a different paradigm for the climate. The current paradigm is that climate is a system in which temperature slavishly follows the changes in inputs. Under my paradigm, on the other hand, natural thermoregulatory systems constrain the temperature to vary within a narrow range. In the last century, for example, the temperature has varied only about ± 0.3°C, which is a temperature variation of only about a tenth of one percent. I hold that this astonishing stability, in a system whose temperature is controlled by something as fickle and variable as clouds and wind, is clear evidence that there is a strong thermostatic mechanism, or more accurately a host of interlocking thermostatic mechanisms, controlling the temperature.
However, this brings up a new question—although the change in temperature is quite small, with changes of only a few tenths of a percent per century, less than a degree, sometimes the global average temperature has been rising, and sometimes falling.
So what are some of the things that might be causing these slow, century or millennia long drifts in temperature? Is it changes in the sun? I think that the explanation lies elsewhere than the sun, and here’s why.
The temperature control system I describe above, based on the timing and duration of the onset and existence of emergent temperature phenomena, is temperature based. It is not based on the amount of forcing (downwelling solar and greenhouse radiation).
By that I mean that the control system starts to kick in when the local temperature rises above the critical level for cloud emergence. As a result, by and large the global average temperature of the planet is relatively indifferent to variations in the level of the forcing, whether from the sun, from CO2, from volcanoes, or any other reason. That’s why meteors and volcanoes have come and gone and the temperature just goes on. Remember that at the current temperature, the system variably rejects about a quarter of the available incoming solar energy through reflections off of clouds. We could be a whole lot hotter than we are now, and we’re not …
This means that the system is actively regulating the amount of incoming solar energy to maintain the temperature within bounds. It doesn’t disturb the control system that the solar forcing is constantly varying from a host of factors, from dust and volcanoes to 11 and 22 year solar cycles. The thermoregulation system is not based on how much energy there is available from the sun or from CO2. The resulting temperature is not based on the available forcing, we know there’s more than enough forcing available to fry us. It is set instead by the unchanging physics of wind and wave and pressure and most of all temperature that regulates when clouds form … so when the sun goes up a bit, the clouds go up a bit, and balance is maintained.
And this, in turn, is my explanation of why it is so difficult to find any strong, clear solar signal in the temperature records. Oh, you can find hints, and bits, a weak correlation to this or that, but overall those sun-climate correlations, which under the current paradigm should show visible effects, are very hard to find. I hold that this shows that in general, global average temperature is not a function of the forcing. The sun waxes and wanes, the volcanoes go off for centuries, meteors hit the earth … and the clouds simply adjust to return us to the same thermal level. And this weak dependence of output on input is exactly what we would expect in any significantly complex system.
So if the sun is not guilty of causing the slow drift in global average surface temperature over the centuries, what other possible defendants might we haul before the bar?
Well, the obvious suspects would include anything that affects the timing and duration of the onset and existence of clouds, or their albedo (color). Unfortunately, cloud formation is a complex and poorly understood process. Water droplets in clouds form around a “nucleus”, some kind of particle. This can be sea salt, dust, organic materials, aerosols, a variety of types and species of microorganisms, black carbon, there are a host of known participants with no clear evidence on how or why they vary, or what effects they have when they do vary. Here’s a quote from the abstract of a 2013 scientific paper, emphasis mine:
The composition and prevalence of microorganisms in the middle-to-upper troposphere (8–15 km altitude) and their role in aerosol-cloud-precipitation interactions represent important, unresolved questions for biological and atmospheric science. In particular, airborne microorganisms above the oceans remain essentially uncharacterized, as most work to date is restricted to samples taken near the Earth’s surface. SOURCE
Here’s another example:
Cumulus clouds result from the ascent of moist air parcels. An unresolved issue in cloud physics is why observed cumulus cloud droplet spectra even in the core of cumulus clouds are broader than the spectra predicted by cloud droplet nucleation and condensational growth in adiabatically ascending parcels (Pruppacher and Klett, 1997). SOURCE
Cumulus clouds are one of the most common types on earth and we don’t even understand cloud nucleation there. The problem is that the size and composition of atmospheric aerosols, and the complex interaction between those aerosols and the various organic and inorganic atmospheric chemicals, ions, free radicals, and natural and man-made particles, plus variations in the type and amount of microbial populations of the atmosphere, plus the ability of one chemical to adsorb onto and totally change the surface properties of another substance, all have the potential to affect both the timing and the duration of both cloud formation and precipitation, along with cloud optical properties. As such, they would have to be strong contenders for any century-scale (and perhaps shorter-scale) drifts in temperature.
Another possible cause for the slow drift might be the proposed cosmic ray connection, sun’s magnetic field –> cosmic ray variations –> changes in cloud nucleation rate. I see no theoretical reason it couldn’t work under existing laws of physics, I made a “cloud chamber” as a kid to see radioactivity come off of a watch. However, one difficulty with this cosmic ray connection is that the records have been combed pretty extensively for sun/climate links, and we haven’t found any strong correlations between the sun and climate. We see weak correlations, but nothing stands out. Doesn’t mean they don’t exist, but it may be indicative of their possible strength … or as always, indicative of our lack of knowledge …
Another cause might be the effect on thunderstorms of gradual changes in the earth’s electromagnetic fields. Thunderstorms have a huge (think lightning bolts) and extremely poorly understood electromagnetic complement. They serve an incredibly complex electromagnetic circuit that couples the atmosphere and the surface. It ties them together electromagnetically from the “sprites” that form when thunderstorms push high above the surrounding tropopause, and from there in various ways through dimly glimpsed channels the electromagnetic current runs down to and up from the ground. Thunderstorms also are independent natural electrical Van de Graaf machines, stripping electrons in one part of the thunderstorm, transporting them miles away, and reuniting them in a thunderous electrical arc. We have no idea what things like the gradual changes in the location of the Magnetic Poles and alterations in the magnetosphere or variations in the solar wind might do to the timing and duration of thunderstorms, so we have to include slow alterations in the global magnetic and electrical fields in the list of possibilities, perhaps only because we understand so little about them.
The next possibility for slow changes involves the idea of bifurcation points. Let me take the alteration between the two states of the Pacific Decadal Oscillation as an example. In each of the states of the PDO, we have a quasi-stable (for decades) configuration of ocean currents. At some point in time, for unclear reasons, that configuration of ocean currents changes, and is replaced by an entirely different quasi-stable (for decades) state. In other words, somewhere in there is a bifurcation point in the annual ebb and flow of the currents, and at some point in time, the currents take the path not recently travelled and as a result, the whole North Pacific shifts to the other state.
Now, even in theory one of these two state has to be more efficient than the other in the great work of the heat engine we call the climate. That great work is moving energy from the equator to the poles. And in fact there is a distinct difference, one of the two states is called the “warm” state and the other is called the “cool” state.
Intuitively, it would seem that IF for whatever reason the Pacific Decadal Oscillation stayed permanently in one state or the other, that the world would end up either warmer overall or cooler overall. Let me explain why I don’t think the PDO or the El Nino/La Nina or the North Atlantic Oscillations are responsible for slow drifts in the regulated temperature.
The reason is that just like the thunderstorms, all of those are emergent phenomena of the system. Take the PDO as an example. Looking at the Pacific Ocean, you’d never say “I bet the North Pacific stays warm for decade after decade, and then there’s a great shift, all of the sea life changes, the winds change, the very currents change, and then it will be cold for decade after decade”. No way you’d guess that, it’s emergent.
And because they are emergent systems, I hold that they too are a part of the interconnected thermal regulation system, which in my view includes short term emergent systems (daily thunderstorms), longer term (multi monthly Madden Julian oscillations), longer term (clouds cooling in summer and warming in winter), longer term (3-5 years El Nino/La Nina), and longer term (multidecadal PDO, AMO) emergent systems of all types all working to maintain a constant temperature, with many more uncounted.
And as a result, I would hold that none of those emergent systems would be a cause of slow drift. To the contrary, I would expect that they would work the other way, to counteract slow drift and prevent overheating.
Moving on, here’s an off-the-wall possibility for human induced change—oil on the global oceans. It only takes the thinnest, almost monomolecular layer of oil on water to change the surface tension, and we’ve added lots of it. This reduces evaporation in two ways. It reduces evaporation directly by reducing the amount of water in contact with the air.
The second way is by preventing the formation of breaking waves, spray, and spume (sea foam). Spray of any kind greatly increases the water surface available for evaporation, depending on windspeed. Remember that evaporation due to wind speed is the way that the thunderstorm is able to sustain itself. So when the amount of area evaporating is decreased by ten or twenty percent due to lack of spray, that will commensurately decrease the evaporation, and thus affect the timing of the onset and the duration of thunderstorms.
OK, you gotta love this. I thought “time for more research” after writing the last paragraph, and I find this:
Sailors who traditionally dumped barrels of oil into the sea to calm stormy waters may have been on to something, a new study suggests. The old practice reduces wind speeds in tropical hurricanes by damping ocean spray, according to a new mathematical “sandwich model”.
As hurricane winds kick up ocean waves, large water droplets become suspended in the air. This cloud of spray can be treated mathematically as a third fluid sandwiched between the air and sea. “Our calculations show that drops in the spray decrease turbulence and reduce friction, allowing for far greater wind speeds – sometimes eight times as much,” explains researcher Alexandre Chorin at the University of California at Berkeley, US.
He believes the findings shed light on an age-old sea ritual. “Ancient mariners poured oil on troubled waters – hence the expression – but it was never very clear what this accomplished,” says Chorin. Since oil inhibits the formation of drops, Chorin thinks the strategy would have increased the drag in the air and successfully decreased the intensity of the squalls.
Hmmm … good scientists, not such good sailors. As scientists, I’d say they only have part of the answer. They should also run a calculation on the increase of the evaporative area due to the spray, and then consider that the hurricane runs on evaporation. That’s why they die out over the land, no moisture. Cut down the spray, put oil on the water, cut down the evaporation, cut down the power of the storms. And just like you get sweatier and hotter if a muggy day prevents evaporation, the same is true of the ocean. If you cut down evaporation, it will get warmer.
Of course, the counter-argument to the oil-on-the-water cuts evaporation and warms the ocean hypothesis was World War II. It put more oil into all of the oceans of the world than at any time before or since, and during the war in general the world was quite cold … dang fact, they always get in the way.
Having said that, as a blue-water man I can assure you that the authors of that claim are not sailors. Sailors don’t dump oil in the water to lower the wind speed, that’s a landlubber fantasy. They do it because it prevents waves from breaking and drops and spray from forming, so it can help in rough conditions. It doesn’t take much, you’d be surprise at the effect it has. You soak a rag in motor oil and tow it a ways behind the boat when you are drifting downwind. If the Coast Guard catches you, you’ll get a ticket for causing a sheen on the water and rightly so, but if it saves your life once, it’s probably worth it. Heck, when you’re caught in a big offshore blow, if it just has a placebo effect and reduces your personal pucker factor, its probably worth it … but I digress.
One thing is clear, however. The climate has been on a slow drift up and down and up and down, warm in Roman times, cold in the Dark Ages, warm in the Middle Ages, cold in the Little Ice Age, warm now … so while humans may indeed play some part the post-1940′s drift (down, then up, now level), it’s likely not a big part or we would have seen it by now … and in any case if we did have an effect, we still don’t know how.
I want to close by noting the power of the paradigm. If the paradigm is that greenhouse gases are the likely reason for slow climate drift because you assert (curiously and incorrectly) that temperature slavishly follows forcing, then you will look for variations in all the things that affect those GHGs.
But once the paradigm shifts to describing the climate as composed of interlocking active thermoregulatory mechanisms, we find ourselves with a range of entirely different and credible candidates for slow drift that are untouched and uninvestigated. It may be something above, or something I haven’t even considered, the change in plankton affecting the clouds or something.
This is why the claim that we have identified the “major forcings” as being say CO2 and methane and such ring hollow. Those are only the major players within the current paradigm. The problem is, that paradigm cannot explain a system so tightly thermoregulated that over the last century, the global average surface temperature only varied by ± one tenth of a percent … engineers, please correct me if I’m wrong, but given volcanoes and aerosols and the like that is a record that any control systems engineer would be proud of, and it is done with things as ephemeral as clouds. To me, that fact alone proves that the earth has a thermostat, and a dang precise one for that matter. A truly wondrous and marvel-filled planet indeed.
In friendship and exploration of the aforesaid marvels,