Airborne campaign solves parts of the riddle of clouds
UNIVERSITY OF HAMBURG
CREDIT: MPI-M
In a major field campaign in 2020, Dr. Raphaela Vogel who is now at Universität Hamburg’s Center for Earth System Research and Sustainability (CEN) and an international team from the Laboratoire de Météorologie Dynamique in Paris and the Max Planck Institute for Meteorology in Hamburg analyzed observational data they and others collected in fields of cumulus clouds near the Atlantic island of Barbados. Their analysis revealed that these clouds’ contribution to climate warming has to be reassessed.
“Trade-wind clouds influence the climate system around the globe, but the data demonstrate behavior differently than previously assumed. Consequently, an extreme rise in Earth’s temperatures is less likely than previously thought,” says Vogel, an atmospheric scientist. “Though this aspect is very important for more accurately projecting future climate scenarios, it definitely doesn’t mean we can back off on climate protection.”
To date, many climate models have simulated a major reduction in trade-wind clouds, which would mean much of their cooling function would be lost and the atmosphere would consequently warm even more. The new observational data shows that this isn’t likely to occur.
What is certain is that, as global warming progresses, more water on the ocean’s surface evaporates and the moisture near the base of trade-wind clouds increases. In contrast, the air masses in the upper part of the clouds are very dry and only become slightly moister. This produces a substantial difference in moisture above and below. In the atmosphere, this is dispelled when the air masses mix. The previous hypothesis: drier air is transported downward, causing the cloud droplets to evaporate more rapidly and making it more likely that the clouds will dissipate.
The observational data from Barbados now offers the first robust quantification as to how pronounced the vertical mixing actually is, and how this affects moisture and cloud cover as a whole. As such, it is the first data to shed light on a process that is essential to understanding climate change. In brief: more intensive mixing does not make the lower layers drier or make the clouds dissipate. Rather, the data shows that the cloud cover actually increases with increasing vertical mixing.
“That’s good news, because it means that trade-wind clouds are far less sensitive to global warming than has long been assumed,” says Vogel. “With our new observations and findings, we can now directly test how realistically climate models portray the occurrence of trade-wind clouds. In this regard, a new generation of high-resolution climate models that can simulate the dynamics of clouds around the globe down to scales of one kilometer are particularly promising. Thanks to them, future projections will be more accurate and reliable.”
The month-long field campaign EUREC4A (2020) was designed by the team members around extended flights with two research aircraft, which were equipped with different instruments and operated at different altitudes, and shipboard measurements from the R/V Meteor — A German research vessel managed by the University of Hamburg. One plane was used to drop hundreds of atmospheric probes from an altitude of nine kilometers. As they fell, the probes gathered atmospheric data on the temperature, moisture, pressure and wind. The other plane surveyed clouds at their base, at an altitude of 800 meters, while the ship performed surface-based measurements. The result: an unprecedented database that will help to understand the unclear role of clouds in the climate system – and to more accurately predict their role in future climate change.
Whether clouds have a cooling or warming effect depends on how high they are. With a maximum altitude of two to three kilometers, the trade-wind clouds examined here are comparatively low, reflect sunlight, and cool the atmosphere in the process. In contrast, higher clouds amplify the greenhouse effect, warming the climate.
Publication: Vogel R, Albright AL, Vial J, George G, Stevens B, Bony S (2022): Strong cloud-circulation coupling explains weak trade cumulus feedback; Nature, DOI: 10.1038/s41586-022-05364-y https://www.nature.com/articles/s41586-022-05364-y
Nature Research Briefing: https://doi.org/10.1038/d41586-022-03640-5
JOURNAL
Nature
DOI
METHOD OF RESEARCH
Observational study
SUBJECT OF RESEARCH
Not applicable
ARTICLE TITLE
Strong cloud-circulation coupling explains weak trade cumulus feedback
ARTICLE PUBLICATION DATE
30-Nov-2022
COI STATEMENT
No COI
“but the data demonstrate behavior differently than previously assumed”
I should think if it’s science there should be no assumptions.
It’s usually not possible to do any kind of scientific analysis without making assumptions. What separates science from B.S. is testing the assumptions. In this case the asumptions were tested and found to be wrong.
right- but at least good scientists will make it clear they are making assumptions so the results of their work depends on the assumptions- but too many climate scientists deemphasize that they’re making assumptions and hope we forget those assumptions so their work will appear to be truth
Many of the problems in my Engineering Thermo textbook had the phrase “justify your assumptions” with understanding that the problem would be too difficult to sole without making some assumptions.
A corollary of this is knowing what one doesn’t know.
You’re obviously correct, Erik. But we’ve had the “science is settled” mantra shoved at us for many years now so anything that begins to refute the claim is bound to come under fire.
The “science is settled” was a big red flag for me, knowing enough about the history of science to know that science as a whole is never settled.
“I should think if it’s science there should be no assumptions.”
Indeed, particularly when the science is so very “settled”!
Well, that is progress, but what they haven’t yet realised is that changes in vertical mixing will have equal and opposite effects in rising and falling air so the net effect overall is zero. Analysing vertical mixing is therefore pretty pointless. Cloud formation in rising air is matched by cloud dissipation elsewhere in falling air.
To get a change in average global temperature it is necessary to change planetary albedo and that has to be effected by a change in average total cloud cover. That involves horizontal mixing.
The most likely cause of that is a change in the waviness of jet stream tracks because waviness controls the length of the lines of air mass mixing around the globe. Short lived clouds do arise from vertical mixing but long lived cloudiness arises from horizontal mixing where there is contact between air masses of different characteristics.
Little by little, step by step, appearing cracks are growing wider.
Stephen….”cloud formation matched by… dissipation”….We can’t be sure of that. A volume of saturated air at ground level takes up 5 times as much volume by the time it reaches 200mB at top of troposphere, should it rise that far, forming cloud cover as it convects upwards. So roughly covers twice as much ground area with clouds as there is clear sky between the clouds. (Somewhere between square root of 5 for pancake clouds and cube root of 5 for spherical clouds)
And Earth’s cloud cover turns out to be 66% which happens to be twice the clear sky 33%….OK, so its probably a fluke, but maybe have a look at thunderheads….
How about rain? Or hurricanes?
IMHO, “average global temperature” is impossible to determine. Please correct me if I am in error with “this assumption”.
This work is causing all kinds of problems by eliminating high ECS scenarios. It is obvious it is being selectively dismissed by those who are rooting for warming. To some, the optimal warming is in the range 1.5 – <2C so they can say “see, I told you so”, and remaining below 2C so they can say “see, look how we solved the problem.” It is a very narrow range they are shooting for to justify their existence. Their legacy is at stake, and any suggestion that warming might be in the far low end of projection, regardless of intervention, is seriously problematic.
It should be noted that the basis for total societal transformation is the precautionary principle due to extreme high end of ECS conjecture. If such scenarios are eliminated it impacts all economic calculus. IMO it is good news to eliminate unphysical assumptions, so we can get back to a sensible debate about environmental management priorities. Once the extreme ECS scenario boogeyman is gone it’s all hands on deck to restore credibility to environmental science. For I must admit that for the past while has been an embarrassment to be an environmental practitioner, whereupon any funding application and public communication pieces must make a link to global warming. In the process this has become a hindrance to gaining trust and respect in the communities in which we serve, and has been net damaging to environmental amelioration. In fact, most of our budgets have now been displaced and put into green tech venture capital, tech subsidies, and litigation.
The problem is that all environmental science has been tainted by the AGWF for the last thirty years and has to be re-done from the start.
That is not the case. The fundamentals of my sector of soils and watershed management have not changed since the time of F D Roosevelt. It is not glamorous, but the solutions to ecosystem desiccation and associated drought and flood hazards are well known. It is the bureaucrats who must be retrained, and perhaps students who graduated since about 2004. Additionally, journalists and politicians who have learned that any and all environmental hazards are to be associated with AGW, when in fact the issues are far more straightforward. The engineers know this, as they look at IDF curves and note hardly any change, as they cringe at infrastructure maintenance budgets and larger stormwater needs. It is a deficit in investment and education where it is needed, but the science is well understood. An overhaul of insurance and regional planning may be required, in addition to realtors unaware of the hazards to which their clients are being exposed (irrespective of climate changes). Ecologists, hydrologists, and engineers know exactly what’s up.
The worst part is that massive resources are being wasted on something that can never do what it is intended to do for a reason that does not exist.
One certainty with climate change is that snow is going to increase in the northern hemisphere. If you need to clear snow with machinery then that requirement will ramp up. Good luck using battery powered vehicles for that purpose.
The average global temperature will rise a lot more before the snow starts accumulating. I expect no levelling in trend before 2200.
I doubt we will see ice accumulating on the large land masses again before the end of this century.
It is encouraging to observe Iceland is already accumulating ice again. Its southern tip is 63N.
The snowline on the east and west coasts of North America should by descending now or soon will be.
It is an interesting hypothesis but falls into a global perspective that is irrelevant to practical environmental management. Such minor anomalies over centuries are easily captured in evolving regional engineering design standards.
This is what such documents have always been meant to do, as it has always been understood that things change from place to place.
This, when it’s practically 50 / 50 odds that any particular station will be warming/cooling or having changing precipitation intensity. Thus, engineering design standards are highly regionalized.
In my country of Canada, where warming is apparently double the global average, water managers are working with the following trends:
93% of stations show no trend in precipitation intensity
Rainfall maxima have significant increases at 4% of stations.
Rainfall maxxima have significant decreases at 3% of stations.
It is totally random noise and the bulk of design standards in the most populous regions are still using Hurricane Hazel data from 1954 and the so-called Timmins event from 1961.
Media / marketing / reporting claims that confuse GCM output trends as having any bearing on regional changes diverts focus from key risk drivers and resilience design priorities. It is a total error of judgement. One must not confuse the curiosities of global climate science, and their puny average anomalies, with the practical environmental challenges of any given community. These subjects must be kept completely separate.
Full documentation
https://nrc-publications.canada.ca/eng/view/object/?id=27058e87-e928-4151-8946-b9e08b44d8f7
First of all, temperatures aren’t rising, but flat (even falling in places).
Second, glaciers are already growing, not shrinking
Thirdly, if you want to die a miserable, cold death in a dark cave, fine. But don’t impose a death like that on everyone else.
> The month-long field campaign …One plane was used to drop hundreds of atmospheric probes from an altitude of nine kilometers. …The other plane surveyed clouds at their base, at an altitude of 800 meters, while the ship performed surface-based measurements. The result: an unprecedented database…
So… ONE MONTH of sparse data refutes decades of settled science.
I thought i was beyond emotions concerning climate “science” but I wish to donate my share of the multiple Nobel’s coming our way to endowing WUWT with a permanent funding stream.
You’re confusing me. Or is that a sarc on “settled science”.
It is a loose paraphrase amalgam of several Feynman quotes. “I would rather have questions that can’t be answered than answers that can’t be questioned.” “It doesn’t matter how beautiful your theory is, it doesn’t matter how smart you are. If it doesn’t agree with experiment, it’s wrong.” “Progress in science comes when experiments contradict theory.” ~ Richard P. Feynman
I am sure, however, that the ‘hundreds’ of probes were assiduously collected and reused, perhaps after an onboard service.
Auto
This is more of an admission that GCMs do not model clouds and require parameterization to make up that lack. Yet another reason why computer models are mostly useless.
If they’d actually get down to the fact that the GCMs don’t even model climate at all and admit that the temperature at ground level doesn’t represent jack shit to begin with… THEN we can start doing science.
Gravity defines the amount of energy per measured volume and the temperature of that air means exceptionally little both locally and globally for “climate”
They also don’t naturally generate emergent properties (like Hadley cells or thunder storms), you have to specifically program them in. An early climate model had a massive deciduous rain forest where the Sahara Desert is. This creates massive opportunity to only program them in a way that will create the desired level of warming.
the clouds aren’t in the level of atmosphere they claim to be representing through their fraud
And the science was settled 100 years ago.
It amazes me that no one in academia has attempted to understand convective instability over oceans by actually quantifying what happens.
On the other hand if you lack the understanding in physics to believe that there is a “greenhouse effect” controlling earths energy balance and back radiation from cold to hot exists then there is not much hope.
Precession has created “global warming” 4 times in the last 500k years that ended interglacials. Why wouldn’t “global warming” do the same thing now.
Various people here at WUWT, often WE, have said the same for years, and so did Lindzen, not to mention Manabe and Wetherald’s 1967 paper, now over half a century old…
https://geosci.uchicago.edu/~archer/warming_papers/manabe.1967.rad_conv_eq.pdf
But apparently present day CliSighs don’t know sh1t about clouds or just don’t want to bother calculating how much sunlight they reflect.
More (un) settled science
“Though this aspect is very important for more accurately projecting future climate scenarios, it definitely doesn’t mean we can back off on climate protection.”
Get out of jail card. All climate models should be reassessed against the ‘new’ cloud revelations. Funny, not so new to sceptics.
The study throws cold water on the Human-caused Climate Change meme, so they are going to need that get out of jail free card.
It’s better than the alarmists thought!
Can we stop wasting trillions of dollars on windmills and solar now?
Perhaps they should have gathered this data *before* we wasted all that money trying to rein in CO2.
“In this regard, a new generation of high-resolution climate models that can simulate the dynamics of clouds around the globe down to scales of one kilometer are particularly promising.”
Right. It will still be parameterized and tuned, and the step-iterated computations will still generate a buildup of uncertainty beyond anything useful for diagnosis or prediction concerning GHGs.
That said, it is good to better understand cloud dynamics.
““Trade-wind clouds influence the climate system around the globe, but the data demonstrate behavior differently than previously assumed. Consequently, an extreme rise in Earth’s temperatures is less likely than previously thought,” says Vogel, an atmospheric scientist.”
There’s that magic word. “assumed”.
Somebody assumed that MORE evaporation would lead to DRIER air?
No wonder it comes from YouReekAlot!
Not as silly as it sounds. According to Dr. William Gray, more evaporation makes the air lighter and enhances convection. This increases the speed of upward air flows driving them higher into the cold upper troposphere. Because it is colder the higher you get, you end up with increased condensation and remove more water vapor. The result, drier air in the upper regions of the troposphere where the water vapor greenhouse effect is most significant.
And with increased condensation you have more cloud cover, more sunlight reflected into outer space, and cooling at the surface…..
Collect site specific data and minimal altitudes: “fields of cumulus clouds near the Atlantic island of Barbados”, analyze that data and then make global assumptions and claims.
Logic and science fail.
Understanding clouds will be important in understanding the real effects of increases in CO2. The surface is not warmed to any great extent by DWIR increases due to boundary layer equilibrium processes. However, evaporation will increase.
This increase enhances convection (moist air is lighter) which leads to increased condensation high in the troposphere with a corresponding reduction in water vapor. As a result, the slight warming effects of increased CO2 are countered by a decrease in high altitude water vapor where greenhouse effects are most important. The net result is a constant opacity as discovered in Miskolczi 2007, 2010, 2014.
There should also be an increase in clouds and rainfall. That is what needs to be further studied.
She doesn’t want to back off climate protection? She’s got it all worked out doesn’t she?
I thought the science was settled….
On a less sarcastic note, the models have an inaccurate assumption built into them. This is part of the reason they have consistently overpredicted warming. Will the modelers go back and fix this? I don’t think so.