Perhaps it doesn’t rise to the level of hypothesis, perhaps only to speculation or muse… but “below a thesis” in any case.
The data points are all personal observation at this point, so would need a lot of work to prove up a data set. The idea is that changes in air flow cause changes in humidity that lead to changes in measured temperatures, and that is the cycle of warmer / colder over a 60 ish year cycle.
Sparse, at best. Just enough to cause me to notice. Also, this is California observations only. I have no position on how things would have manifest in, say, West Texas or Hampton or Nome or Wellington. An interesting question would be if others noticed changes on the same cycle, but not necessarily the same changes.
Salt. The salt shakers are caking. Realize that in California humidity caking of salt in the shaker is rare in most areas. The State is a natural desert in most areas. I’ve lived in the same house for about 1/4 century and in a 200 mile radius for almost 2/3 century. I’ve been paying attention to salt for about the last 57 years (since my Dad showed me how putting rice in a salt shaker would prevent caking during a wet humid spell in the restaurant in about 1960). Ever since that day, I’ve noticed when salt shakers had rice in them, and not. Where I was. What the weather was like. Was it needed or just prophylactic caution. (Hey, it’s what “people like me” do to keep from being bored out of our skulls in the humdrum of normal life.) So for 1/4 century we’ve never used rice in the salt at home. Same kitchen. Same cook. Same ventilation and heater / AC. Same foods cooked the same ways. Nothing to change humidity. We moved in after The Great Pacific Shift which was just a few years before I came to this area. The Shift came a few years after my last memory of using rice in the salt in my prior turf, north of Sacramento. So for about the duration of the Great Pacific Climate Shift, there has been zero caking, now, post the 1998-2005 or so change, it has returned.
Wind. Starting at about 6? years old, I used to sit and daydream watching leaves a lot. It got to be a habit that continues to today. Just outside my living room picture window is a nice pear tree. I’ve watched those leaves for the last 1/4 century. Prior to the mid-70s, the leaves in my old home town tended to “shimmer” and there were wavy changes of direction from place to place. At the same time, aviation was discovering “micro-bursts” and in the early ’70s pilot ground school, great emphasis was put on avoiding the weather conditions that create those down drafts. After the Great Shift, losses of jet liners to downdraft were much less. Typically I’d attributed it to more weather radar and awareness, but perhaps the number and severity of downdrafts has reduced? Do we have data to know?
What I can say with certainty, is that the ‘summer breezes’ and ‘puffy wind’ causing leaves to move about, was replaced with a more linear wind displacing them sideways in winter along with more still air in spring / summer / fall. Lest bursty puffy wind. Linear storm winds and quiet when calm. Again in that 1998-2005 range, I saw the shimmer return. I’d missed it for decades. I’d look out my window at the pear tree and see leaves just static. I attributed it to the area… and would remember the shimmer from pre-70s. Well, when it returned, I noticed. It is a gentle, about 2 to 5 mph I’d guess, puffy wind. One bush or tree will move when one a dozen feet away is static. Standing in it, the direction feels more vertical. There is a sideways component, but that has two parts. A bias from any general air flow, and a random component for each rustle of the leaves. My interpretation of it is a vertical wind burst inside a slight horizontal bias. The effect is that the “shimmer” is back, and it is here. A bush will move and shake, then be still. Then another moves, and is still… The dancing of the trees is back… after all these years.
Rain. It was flooding and a rainy mess pre-’70s here. Governor Brown Sr. built the California Aqueduct and dams all over to stop the flooding. Skies were often overcast in the Bay Area, and it was always cool to cold. I remember visits to San Francisco during the ’60s to ’70s and it was always cold and dank. Even in summer. Often worse in summer as the fog belt moved in. Then in the ’80s and ’90s, things dried out some and got warmer. I was working in San Francisco then and there were some warm dry sunny lunch times at the piers. In about 1977 we had a heck of a drought (far worse than anything lately). I moved to the bay area and complained about never feeling really warm in Summer. Then about 1980 summers started being drier (less dank) and warmer. I decided maybe it was OK, and stayed. Now I’m typing this under overcast sky, in a dank cold Spring. A couple of decades of warm Memorial Day BBQs prancing by in the memory parade. Not today. Today the salt didn’t want to come from the shaker without tapping it, even with rice. Today I want to put a jacket on. Since that 1998-2005 range shift, reports of flood have gone way up, globally, but specifically here in California. I’ve had a whole series of “Flooding Drought” postings. The humidity and rain are back.
There are some other odds and ends, but likely of little relevance. The smell of the air (more ‘marine’ – I’m one mountain range from the ocean and a few miles from the Bay). The late burn off of morning overcast. The mountain passes closed with heavy snow that I’ve not seen since pre-70s. That kind of thing.
Which brings us to the question of cause.
This all started shifting back to cold and dank and breezy when the sunspots went way low in that 1998-2005 range. We know that the atmospheric height lowered then, a lot. (NASA reports on satellite drag reduction, lifetime of fuel extension, direct measurements, etc.) We know that the EUV and UV and even blue in the light diminished and the IR and Red increased while TSI (Total Solar Irradiance) only dropped a minuscule amount. A short while after that, I started noting the bursty wind returning in various comments.
So how does a change of spectrum change wind and humidity, and through them temperatures recorded at ground level? Nobody knows. It is all speculation. What we do know is a lot of EUV is absorbed in the upper layers of the atmosphere, making them warmer ( i.e. thermosphere and stratosphere) and this is part of the ‘puffing up’ of atmospheric height during high sunspot counts (important to keeping low orbiting satellites ‘up there’ so watched by NASA). Lower EUV would mean lower air height (for any given density) and colder (in the sense of less contained heat, temperature may be changed by density / compression / flow effects for any given heating).
A more vertically compressed, cooler, and less energetic upper atmosphere would, IMHO, be more prone to a vertical descent. (But better atmosphere modelers then me need to address that one). It would certainly have less heat in it as it descends in the Polar Vortex, so the poles ought to get significantly colder. Since compression heating in descent is a function of density, not altitude, the compression heating in descent ought not to change with a lower height; however: Potential Energy to Kinetic Energy conversion is a function of height… so descending parcels of air will have less PE to KE conversion and will end up with less thermal energy at ground level. I.e. they will be colder than if descended from greater height. A significant amount? Need some math and physics and actual data to know. Furthermore, the lowered height for any given layer means inertial effects have less distance to act. A downburst has less time to be stopped, for example, before it hits the ground.
Air Summary: So, in summary, I’d conclude less EUV heating of the thermosphere and stratosphere results in lower atmospheric height, less temperature is likely (though water effects need addressing and other interactions since heat and temperature are only quasi-related) and lower PE to KE heating in descent. Colder poles, and perhaps more tendency to vertical currents. Currents that can’t “run out” as easily and are more prone to reaching ground level; thus the bursty breezes. Similarly, thunderheads that reach the stratosphere will have changes of inertial run and KE to PE conversion, likely changing the character of things like hail and microbursts. Best if a meteorologist tackles those details in that “Dig Here!”.
Meanwhile, the oceans have more IR and red hitting the surface, a lot less UVA and UVB and blue entering to depth, and a small percent total energy less overall. So a lot less energy disbursed through the top 100 M of the oceans, more causing prompt evaporation at the ocean surface when the IR and red heat the top skin layer in contact with air. This ought to result in more water evaporation, more precipitation, and more humidity. Especially in any area near a large body of water. Furthermore, this lack of heating at depth will tend to slow the thermal circulation of the oceans. Take heat out of a heat engine, it slows down. Now this is a heat differential thing, so there is a race condition between colder polar air and less warmed 100M oceans as to which dominates. That race is likely to change over time. This matters. Essentially, the “heat engine” of the ocean currents slows down as it is starved of heating, while the “heat engine” of the air is accelerated as it is getting an ever larger dose of heated water vapor. Rains and humidity pick up near real time while polar water needs a decade or three to cool. All the makings of an oscillator.
Water summary: The oceans act as a multidecadal heat capacitor, storing EUV / UV / Blue heat hundreds of feet down when charging, then releasing it slowly for more decades as wind and currents lead to overturning of the water. Air is a rapid humidity cycler. When peak heated ocean suddenly goes to low UV high IR, the oceans respond nearly real time with more evaporation and a more humid air layer. Slowly, over the duration of the ocean discharge cycle, humidity levels and precipitation will drop, but in the immediate time after that transition, you have hot ocean with IR heated skin in contact with warm air. Lots of flooding and precipitation. At the other end of things, a cooled ocean with little excess heat has the sun transition to a high UV / Blue stage, and suddenly it gets a cooler skin layer. Low humidity, low precipitation. Droughts. Think 1930s. So each end of the cycle ought to have a flood / drought signature. Unfortunately, as the hot ocean cools or the cold ocean warms, that signature can turn into other floods and droughts, so a decent degree of statistical sleuthing needed in that “Dig Here!”. I would speculate a 60ish year cycle of an extreme drought (1930s / 1990s) alternating with a 30 year offset flood cycle ( 1950s-60s, 2010s-2020s) but with a minor ‘counter cycle’ at the end of each phase before the transition as the ocean capacitor state changes.
Now “mix and stir”:
So what happens when you mix these too?
More wind, and especially more bursty wind, at the surface ought not to be only over land. Over large bodies of water it will increase evaporation, so increase humidity and precipitation. It will also increase surface mixing, bringing deeper heat to the surface for discharge. Low winds let the deep levels lay still and don’t remove heat as effectively as evaporation. During cooling periods, the discharge of heat from the ocean will be accelerated. During heating periods, storage of heat will be enhanced. Hmmm… sure sounds like an oscillator to me. Meanwhile an ice reduced Arctic with higher evaporative and radiative heat loss arrives just in time for a stone cold EUV deprived Polar Vortex to scrub it of heat. It takes about 18 years for equatorial warmed waters to reach the pole, so this warm water is arriving at the time it most needs cooling, and is hit with an arctic blast. At the other end, cooled water arrives under a thick ice cap just when IR is minimal and the polar vortex is warmer. Oh So Slowly working to let that pole warm up. Two out of phase effects. (My guess is about 1/2 cycle out of phase with the sun). This will tend to stabilize the oscillation and introduce 1/2 cycle artifacts, again, my guess. Slow the switching rate, but not the switch, and put the poles out of phase with the equatorial and temperate weather shifts.
The sun is an energy storage switch. It controls the heating or cooling of the oceans via UVA UVB and Blue light distribution into the depths and via IR / red prompt surface evaporation; and via the EUV it controls atmospheric height and high altitude heating. Oceans and winds respond, but at different resonance rates, with oceans being 18 years for the Pacific polar lag (presentation at Chicago climate conference) and winds being near prompt. (Then there are ice and snow increase effects on their own schedule, being observed now about a decade after the shift back to cooling…) Oh, and add in that there is an 18 year lunar cycle of tides. A nice little “Dig Here!” is to see if they are in phase with the Pacific water movements and / or solar changes as a harmonic.
Essentially, we live on a thermal battery of the ocean, charged by the sun with UV and discharged by the wind and IR driven evaporation. The winds and IR / UV shift with the solar state. This changes winds, tides, evaporation, precipitation, drought and flood, and ice formation. Tickled by the stratospheric variation in EUV heating and vertical wind changes. All this changing weather and temperatures via changes in winds and humidity. The result is a solar driven long duration heating / cooling process, but where differences in cycle time for sun spots vs oceans vs winds vs ice result in various lags and harmonics of the song. It’s jazz, not Mozart. Some themes only heard in their absence at times. Motifs and riffs showing through to remind you, then submerging in an echo of an 18 year old riff… or a 30 year long gone player.
So that’s what the dancing of the trees said to me today. Take some time to watch the trees and leaves, they speak if you listen.