Expanding tropics pushing high altitude clouds towards poles, NASA study finds

Lovely.
What is not described in their supposition is how a temperature change that is less than 1°C increase over the past and previous century, manages to increase the Hadley cells beyond daily and seasonal temperature changes.
Reads like another computer generated orgasmic ‘what if’ program conceptualizing all confirmation bias written into the software.

“…To see if that was the case, Tselioudis and his colleagues analyzed the International Satellite Cloud Climatology Project data set, which combines cloud data from operational weather satellites, including those run by the National Oceanic and Atmospheric Administration, to provide a 30-year record of detailed cloud observations. They combined the cloud data with a computer re-creation of Earth’s air currents for the same period driven by multiple surface observations and satellite data sets…”

A 30-year record of cloud data from satellites…
So the photographic data beamed to earth is fed into a program? Or, are the images transferred by hand and eye?
If this cloud data is so detailed, where is that analysis? By itself, no ghost computer models.
They, combined the data with a computer recreation of Earth’s air currents for the same period…
Presumably to observe concurrent processes; but how can anybody use a model built on surface observations and unspecified satellite data against reality?
Or has NASA come to believe their own hype that computer Models are superior than observations?
In which case, I have a suggestion for building a wonderful retirement model into a virtual reality program for when NASA researchers retire. They should be thrilled!

So NASA realizes their computer models are inadequate. Pretty soon they will discover water is wet.:-)

Re: high clouds (i.e. cirrus, thunderstorm anvil) and warming. At 17 km altitude in the stratosphere, the ice crystals in thunderstorm anvil clouds are at 190-210 K, and so emit a lot less infrared (IR) black body radiation than clouds in the lower troposphere (e.g. at 277 K) since the Stefan-Boltzmann law varies as the 4th power of the absolute temperature. Therefore if the albedo of both types of clouds is assumed the same (which leads to global cooling in both cases), replacing lower troposphere clouds by stratospheric clouds means less emission to outer space. For energy balance, the emission from the clear areas of the Earth’s surface must then be greater, i.e. there will be a small amount of global warming. Of course, the percentage of the Earth’s surface covered by cirrus and thunderstorm anvil clouds is small compared to that covered by normal cumulus type clouds in the lower troposphere, so the effect of increased clouds overall is global cooling during the daytime. At nighttime, the IR lost to outer space from cooler cloud tops is going to be less than that from clear areas of warmer Earth surfaces, so low-lying clouds can moderate heat loss.
Re: flow of hot air and ocean currents from the Equator toward the poles. It seems everyone assumes these convection currents move according to the simple temperature gradient. IMO warm parcels of air and water at the Equator are less dense than cold air and water (above 4 Celsius), so there is a centrifuge effect due to the Earth’s rotation: the less dense warm stuff gets driven towards the Poles, and the Coriolis Effect deflects currents clockwise in the Northern Hemisphere, and counterclockwise in the Southern Hemisphere. Hence the warm Gulf Stream and the Japan Current. For mass balance, colder, denser fluids move toward the Equator by the centrifuge effect of the rotating Earth, and are deflected in the opposite direction by the Coriolis Effect. Hence Clockwise circulation of major ocean currents in the Northern Hemisphere, and Counterclockwise circulation in the Southern Hemisphere. The one major exception is the El Nino, when water piles up from the upwelling cold Humboldt Current moving North and counterclockwise, and then East-West toward New Zealand. When the pendulum has become high enough, the circulation of ocean water reverses, driving the warm winds West-East and we get the El Nino. Because the troposphere has air circulation in 3 dimensions, the Hadley cells extend only so far toward the poles, before the cool dry air sinks back down, warming due to adiabatic contraction, resulting in zones of deserts around the world at intermediate latitudes.

“…“Sometimes when that curtain is pulled, as in the case over the North Atlantic ocean in the winter months, this reduces the overall cloud cover” in the lower mid-latitudes, the temperate regions outside of the tropics, Tselioudis said. The high altitude clouds clear to reveal dark ocean below – which absorbs incoming sunlight and causes a warming effect…”
High altitude clouds clearing will reveal not only dark ocean, but will open a shutter to IR longwave from the ground surface–i.e. expose 305K surface in the subtropics to direct transport to deep space.

Reply to posting by cba, May 7 at 3:00 pm:
Thank you for updating figures on albedo. I derived albedos from the left side of the updated Kiehl & Trenberth energy budget diagram available at https://chriscolose.wordpress.com/2008/12/10/an-update-to-kiehl-and-trenberth-1997 and from the MODTRAN spectrum at https://en.wikipedia.org/wiki/Radiative_forcing . I am willing to concede that your figures are better, but the conclusions are still the same: high clouds are warming. Here are updated calculations:
If the albedo of the surface waters is 0.04, and land is assumed to be 0.12 (similar to that of the Moon), and water covers 2/3 of the Earth’s surface, then the average surface albedo will be [2(0.04) + 0.12]/3 = 0.067 [note that you recalled it is around 0.08, close enough]. Since the overall albedo is given as 0.30 in the literature, if cloud albedo is x, and cloud cover is 62%, then
0.62x + 0.38(0.067) = 0.30
0.62x = 0.30 – 0.0255 = 0.27
x = 0.27/0.62 = 0.44
Then in my calculations, the difference in Bond albedo is 0.44-0.067 = 0.37, so replacing 1% of the surface which is cloudless by reflective cloud will decrease the incoming Solar radiation absorbed at the surface by
1(341.3)(0.37)/100 = 1.26 W/m^2 . This leads to COOLING.
For clouds overall, if the 228 W/m^2 escaping at the TOA (consistent with 240 W/m^2 overall for energy balance, and 260 W/m^2 escaping from a cloudless surface at 288.2 K) remains the same, then the decrease in outgoing TOA emission on replacing 1% of the Earth’s surface which is cloudless with clouds is still 1(260-228)/100 = 0.32 W/m^2, which would lead to WARMING.
The NET result of the two components is still COOLING, by 1.26-0.32 = 0.94 W/m^2.
However, the calculation for a 210 K Thunderstorm Anvil also stays the same, at 1(260-110)/100 = 1.50 W.m^2, and this would lead to WARMING. This time, the NET result is 1.50 – 1.26 = 0.24 W/m^2 WARMING. This result becomes even greater if the high clouds which emit Planck black body radiation are at even lower temperatures, like 190 K or 200 K .
However, as I wrote several times, the importance of high clouds is negligible, given the small percentage of such clouds. The argument has perhaps been used by the CAGW true believers to try to bolster their cause, which is fatally flawed in so many ways. And someone has posted Roy Spencer’s measurements showing warming leads to a decrease in these warming cirrus clouds, so the feedback is negative, not positive. I also agree with geo smith’s skepticism re the transparency of ice crystals in cirrus clouds: if I can see them reflecting white light, their albedo is not zero, so some of the incoming Solar visible radiation will be reflected back to outer space.
IMO the right side of Kiehl & Trenberth’s energy budget diagram is wrong to show back-radiation from greenhouse gases like CO2 and water vapour “warming the planet”. Infrared (IR) photons are emitted from vibrationally excited states, and these are formed (1) either by occasional high-energy collisions with the main air molecules (N2, O2, Ar), or (2) by absorption of IR photons at resonant frequencies. In either case, there must be an outside power source, or else the atmosphere would continually cool. That power source is not incoming Solar radiation, which is in the visible and near-infrared, because the air is mostly transparent at those frequencies. Rather, the mainly visible radiation reaches the Earth’s solid and liquid surface and is absorbed there (albedo 0.07). The energy does not disappear, but shows up as increased vibrations of the zillions of bonds in the surface molecules; i.e. as an increase in temperature. But almost all condensed materials at the Earth’s surface have emissivity close to 1, so emit IR (far-infrared) radiation according to the Planck radiation law for black bodies. At 288.2 K (15 Celsius), the peak emission is close to the central band frequencies for CO2 bond-bending vibrations. So within metres of the surface, almost all the emitted IR photons at 667 cm^-1 are absorbed by CO2 molecules, which are boosted from their ground vibrational state (vibrational quantum number v=0) to the first excited state (v=1). The literature then states that these molecules re-emit IR photons which are then absorbed by molecules higher up, and the process continues until the IR photons finally escape from the atmosphere to outer space. This last sentence is wrong. The literature has failed to understand that the excited state CO2 molecules can lose their extra energy during radiationless collisions with N2, O2, and Ar molecules which constitute 99.9% of dry air and outnumber CO2 by 2500:1. The energy does not disappear, but ends up in increased translational and rotational motions of all molecules departing from the collision zone. I.e. the troposphere has warmed up. This is the true, simple explanation for the atmospheric greenhouse effect. As I wrote previously, the non-polar N2, O2 and Ar molecules do not re-emit IR photons, because the main mechanism for radiation requires a changing electric dipole moment. Therefore talking about “emission from the atmosphere” cannot involve N2, O2 and Ar gas molecules, which do not act like Planck black bodies (spectrometers looking upward at night in the “window” at 900 cm^-1 observe zero emission from the atmosphere). And CO2 and water vapor absorb and emit only at certain frequencies, in bands, not across the entire far-infrared black body spectrum characteristic of the solid and liquid surface of the Earth, or of condensed states (liquid droplets or ice crystals) in clouds.
Is there any observable back-radiation from excited state CO2 and water vapor molecules? Sure there is.
But the energy for each photon in back-radiation initially had to come from a photon of the same frequency emitted from the warm solid and liquid surface of the Earth. Therefore one can consider a back-radiation photon as essentially a photon originally emitted from the Earth’s surface, and after a delay reflected back to Earth. You can see therefore that there is no net change in the energy/temperature of the Earth’s surface.
Back-radiation does slow the rate of cooling of the Earth’s surface at nighttime. This is most obvious on clear winter nights in the Arctic, where nighttime lasts for months. Without any clouds, IR photons emitted from the Earth’s surface at frequencies not absorbed/emitted by CO2 and water vapor just escape directly to outer space (which is at 3 K, the temperature of the cosmic microwave background). This rate of heat loss by radiation can be so great that a temperature inversion occurs (the temperature at several hundred metres altitude can be greater than the surface temperature). Then, heat stored in the troposphere during the daytime/summer can be radiated back to Earth at greenhouse gas frequencies. An excited state CO2 molecule which has lost its energy as an emitted photon lost to the Earth can be replenished by collisional activation with the main air molecules (at 273 K = 0 Celsius, about 3% of all CO2 molecules are in the v=1 excited state at equilibrium, in accord with the Boltzmann distribution). In this way, energy stored during the daytime/summer as enthalpy (heat content) can moderate the temperature drop of the surface. But this is not the same as actually increasing the temperature of the Earth’s surface (warming the surface). During the long nighttime/winter, the average temperature/heat content of the troposphere does decrease, along with the surface temperature.
Where did the non-physical “explanation” for the greenhouse effect, involving radiation exchange to the top of the atmosphere come from? IMO from a false analogy with processes inside stars, accurately modelled by simple linear computer models (spherical stars can be modelled radially, with a shell surface weighting factor of 4.pi.r^2). Heat from exothermic thermonuclear fusion reactions at the center of the Sun is transported via gamma ray photons until they are degraded to visible photons which finally escape from the photosphere. The analogy fails for two main reasons: (1) gamma ray photons lose energy via inelastic collisions with electrons, protons, etc. in the Sun’s interior (Compton scattering), but these free particles have a continuous energy spectrum, so the photons can change frequency at each collision. However, the vibrational energy levels of CO2 and water vapor molecules are quantized, so the energy of the photons cannot be degraded. Constant absorption and re-emission cannot by themselves warm the troposphere; what’s required is inelastic collisions with the main molecules of the atmosphere (N2, O2, Ar) which cannot and do not re-emit IR photons. (2) photons of visible radiation escape at the photosphere because that’s where the atoms (ions and electrons of a plasma) run out; the mean density of the Sun is about that of liquid water on the Earth. There is no similar sudden drop in density at the top of the troposphere which would allow IR photons to “suddenly escape to outer space”. The density at 10 km (equivalent to the top of Mt. Everest) is about 1/4 that at sea level. If CO2 is so powerful an absorber/emitter that photons are essentially completely absorbed within metres of the Earth’s surface, a factor of 4 decrease in density is highly unlikely to allow “escape to outer space”. And a 220 K black body surface at 10 km altitude would emit only 133 W/m^2, nowhere near the 240 W/m^2 needed for energy balance. The literature “explanation” for the greenhouse effect is wrong in so many ways….