By Charles Blaisdell, PhD ChE
Abstract
The term “Vapor Pressure Deficit”, VPD is not a new term it has been used in agricultural management for many years with correlations to plant growth and CO2 absorption. VPD is the difference between the atmospheric saturated water partial pressure, Psw, and the actual water vapor pressure, Pw. It is common knowledge that as VPD approaches zero at any temperature that clouds are likely to form. This paper will explore the relationship between global VPD and global Cloud Fraction (Cover), CC.
In a previous paper, Blaisdell (2023) (4), “Temperature – Dew Point Temperature”, T-Td, was explored as a global correlation to CC. This paper will show that VPD is a better correlation than T-Td. From 1975 to 2022, VPD tracks the increase in climate change. It is common sense that if cloud cover decreases that the earth temperature will increase (assuming all other variables remain constant). VPD correlation to CC is not a perfect correlation but is a hint it may be on the right track of exploring VPD’s role in climate change.
VPD may correlate to cloud cover reflectivity (albedo) in the Dubal et al (2022) CERS data analysis. Dubal et al (2022) (6) showed that the reflectivity of cloudy areas where 2x the reflectivity (short wave radiation out) of clear sky areas, resulting in albedo reduction of the earths cloudy areas being 85% of the total earth’s albedo for the 19 years of data.
A correlation of VPD to cloud cover is a key variable in the “Cloud Reduction Global Warming”, CRGW, theory presented in Blaisdell (2023) (4), CRGW theory starts with localized land-based reduction in Evapotranspiration, ET, (reduction in Specific Humidity, SH). A land-based reduction in SH is mathematically related (through Clause- Chaperon equations) to a VPD increase. The VPD increase is correlated to Cloud Cover decrease: The subject of this paper. The cloud cover decrease lets in more sun which increases temperature and evaporates more water, global SH increases. The result of this natural process can be seen in the current atmospheric “fingerprint” over time: Increasing temperature, increasing specific humidity, decreasing relative humidity, decreasing cloud fraction, and increasing VPD. Initial results indicate cloud reduction could account for a significant part of the current global warming.
CO2 is innocent but clouds are guilty.
Introduction
Scientist have long known that cloud cover, CC, (fraction) of the earth is a key part of seasonal and yearly climate change (11). The pursuit of a cloud model has been going on for years. The earliest models had poor correlation of CC to relative Humidity (11). NASA is working on a computer model, CHIMP6, to predict cloud cover with some success (9). Current International Pannel on Climate Change, IPCC, models assume cloud cover (fraction) is yearly constant (no data to say otherwise per IPCC). NASA satellite data reported in “Climate and Clouds” (12) suggest cloud cover may have decreased since 1982. There is currently no agreement on how much CC has changed or if CC has changed, therefore IPCC climate change models contain no CC change. There is agreement in the scientific community that if CC has changed it should be included in any climate model (11). “Climate and Clouds” (12) (also in (5)) CC data is all this paper must go on. The “Climate and Clouds” (12) data shows that CC can range from 57% to 68 % depending on the hemisphere. The global seasonal range is 59.6% to 65% (range = 5.4%). Modeling (4) calculates a -3.4% change in the average CC could make a +0.85 ⁰C change in global climate. The monthly variability makes small annual averages difficult to see, averages over several years are needed to see any change.
The repetitive seasonal variation of cloud cover (fraction), CC, is show in Figure 1.
The Southern Hemisphere seams to rule the global cloud fraction, CC, (assumed, due to the Earth’s tilt (less sun, cooler) and less land surface (more ocean for water evaporation along with hemispherical interactions). In search of atmospheric variables that correlated to CC the previous paper, (4), presented the relationship between “Temperature – dew point Temperature”, T-Td, and CC to use in the CRGW model for climate change. This paper will introduce the “Vapor Pressure Deficit”, VPD, correlation to CC. VPD is defined as the saturated vapor pressure of water, Pws, – vapor pressure of water, Pw).
Where:
Pws = the saturated water pressure in hPa.
Pw = the actual water pressure in hPa
T = temperature in ‘C
SH = specific humidity in g/kg(da)
RH = relative humidity, %
Eq 1 and 2 are from from Vaisala Oyj (2013) (14):
VPD is used in ET papers on agricultural water management and plant growth models. An excellent summary of VPD in agriculture can be found in Novick et al (2024) (13). In this paper we will look at VPD as a deficit that retards cloud formation. VPD and T-Td both increases over time, Figure 2. Cloud Fraction decrease over time, Figure 3. VPD and T-Td both use the same input of Temperature and Specific Humidity, SH, in different equations.
The result is VPD is more sensitivity to Temperature and SH. Cloud Fraction, CC, vs time has a lower R^2 than VPD because CC is binary, only covers clouds or no clouds. The “cloudy areas” could have variability in radiation reflectivity that is not included in the CC number that affect VPD (such as lower amount to “partly cloudiness” or cloud density). Using Dubal (2022) (6) data, Blaisdell (2023) (3) showed the cloud reflectivity variability in the years 2000 to 2019, decreased while the CC was relatively constant (to be discussed later).
Land vs Marine VPD
Figure 2’s VPD data can be divided into Land and Marine (Meto Office Dashboard (10)), showing the land VPD vs time has a significant increasing slope (cloud reduction). The marine slope is slightly increasing (low R^2), See Figure 4. The differences in slopes suggest the source of the global VPD increase is from the land – consistent with CRGW theory. Mero Office (10) commentary suggest CO2 is the reason for the slope difference?
VPD vs CC
Correlating VPD or T-Td to CC is shown in Figure 5. VPD, (Pws-Pw), is a better correlation to cloud cover. Note the Mt Pinatubo years 1992 to 1998 were removed (Mt Pinatubo ash increased cloud cover in those years).
Figure 5 VPD and T-Td vs CC basic data from Climate Explorer (10)
Interesting Side Bar
Figure 2 uses yearly data because monthly VPD data contains a repetitive strange variability. VPD plotted monthly in Figure 6 showing a strong monthly hysteresis to VPD. (T-Td) has the same hysteresis pattern but less pronounced, not shown).
This author is not a climatologist thus can only guess that the strange pattern in Figure 6 is due to hemispherical interactions and/or the wetter climate ET going from spring to summer vs dryer ET fall to winter. For global climate change, this strange pattern is not of interest but the shifting with time is. Figure 2 plots this shift with time.
VPD and the Dubal et al (2024) CERES data (or Loeb et al (2021)
The Dubal et al (2024) (6) and Loeb et al (2021) (7) 19-year study of CERES data are currently the most accurate measure of the earth’s albedo, decreasing from 0.293 to 0.288 over the 19 years, see Figure 7. The global temperature increased 0.36’C over the 19 years. The cloud cover from Climate Explorer for those years was essentially flat, see Figure xx8, suggesting that cloud cover was not a factor in climate change for those years. Dubal et al (2022) separated the reflectivity (SW radiation out) in to “clear sky” and “cloudy areas” to show that the cloudy areas was 2x more reflective (albedo) than the clear sky, see Figure 9. Considering the cloud cover (67% in Dubal) of the earth the cloudy areas account for 85% to the total earth’s albedo change for those 19 years. The earth’s VPD was increasing (Figure 8) for those years suggesting that clouds were thinning or there were more partly cloudy skies in the cloud cover number. VPD vs earth’s albedo is not that good (not enough years) but in the right direction, see Figure 10.
Climate Change = SW out – LW out = Earth’s Energy (Radiation) Imbalance, EEI.
Cloud cover can affect the LW out by reflecting (down) (or absorbing) LW back to the earth: less clouds = more LW out = cooler. This cloud cover affect is overwhelmed by the main effect of reduced clouds: less cloud cover = increased SW in (to surface) = increased LW out = increased EEI = warmer (see Blaisdell (2023) (2) figure 1 and 2). VPD is only correlated with the SW reflectivity, albedo, Figure 10.
Discussion
Why study a variable the predicts cloud cover? NASA’s data on cloud cover only goes back to 1983 and is very noisy. CERES data is only 19 years. When did cloud cover start to change? VPD may give some clues. Specific Humidity data for the VPD calculation only goes back to 1948 and is increasing to 2022 (not shown) suggesting that cloud cover has been decreasing since 1948.
VPD is an improvement over T-Td vs cloud cover, but not without a high degree of variability. Correlations with Dubal data showed that cloud cover number is not always correlated to VPD or earth’s albedo. Suggesting that VPD at times is increasing while CC is not decreasing, but the reflectivity of the cloud cover is decreasing, possibly explaining the high variability of CC vs time. VPD vs earth’s albedo would be a better metric if more than 19 years was available.
How much has cloud cover or thinning reduced (VPD suggest about 3% reduction in CC since 1975) and what causes global VPD to change? The CRGW theory gives one possibility: Land changes that reduce the water vapor into the atmosphere. It has been almost 5 years since the last NASA report on clouds – time for another. The IPCC is theorizing CO2 and other greenhouse gases.
CO2 is innocent but clouds are guilty.
Bibliography
- “Where have all the Clouds gone and why care? “ by Charles Blaisdell (2022) web link: Where have all the Clouds gone and why care? – Watts Up With That?
- “CO2 is Innocent but Clouds are Guilty. New Science has Created a “Black Swan Event”**” by Charles Blaisdell (2022) web link CO2 is Innocent but Clouds are Guilty. New Science has Created a “Black Swan Event”** – Watts Up With That?
- “More on Cloud Reduction. CO2 is innocent but Clouds are guilty” by Charles Blaisdell web link More on Cloud Reduction. CO2 is innocent but Clouds are guilty (2023). – Watts Up With That?
- “An Unexplored Source of Climate Change: Land Evapotranspiration Changes Over Time.” (2023) By Charles Blaisdell web link An Unexplored Source of Climate Change: Land Evapotranspiration Changes Over Time. – Watts Up With That?
- Climate Explorer web site Climate Explorer: Select a monthly field (knmi.nl) go to “Cloud Cover” or any other data set, for CC click “EUMETSAT CM-SAF 0.25° cloud fraction” click “select field” at top of page on next page enter latitude (-90 to 90) and longitude (-180 to 180) for whole earth. Raw data link is above the graph.
- “Radiative Energy Flux Variation from 2001–2020” (2021) by Hans-Rolf Dübal and Fritz Vahrenholt web link: Atmosphere | Free Full-Text | Radiative Energy Flux Variation from 2001–2020 | HTML (mdpi.com)
- “Satellite and Ocean Data Reveal Marked Increase in Earth’s Heating Rate” (2021) by Norman G. Loeb,Gregory C. Johnson,Tyler J. Thorsen,John M. Lyman,Fred G. Rose,Seiji Kato web link Satellite and Ocean Data Reveal Marked Increase in Earth’s Heating Rate – Loeb – 2021 – Geophysical Research Letters – Wiley Online Library
- Thermodynamics of climate change between cloud cover, atmospheric temperature and humidity (2021) by Víctor Mendoza, Marni Pazos, René Garduño & Blanca Mendoza web link Thermodynamics of climate change between cloud cover, atmospheric temperature and humidity | Scientific Reports (nature.com)
- Ensemble of CMIP6 derived reference and potential evapotranspiration with radiative and advective components by Nels Bjarke (2023), Joseph Barsugli & Ben Livneh link Ensemble of CMIP6 derived reference and potential evapotranspiration with radiative and advective components | Scientific Data (nature.com)
- Met Office Climate Dashboard web Link Humidity | Climate Dashboard (metoffice.cloud)
- “Clouds and relative humidity in climate models; or what really regulates cloud cover?” by Walcek, C. (1996) web link Clouds and relative humidity in climate models; or what really regulates cloud cover? (Technical Report) | OSTI.GOV
- “Climate and clouds” by web site link climate4you ClimateAndClouds
- “The impacts of rising vapour pressure deficit in natural and managed ecosystems” (2024) by Kimberly A. Novick, Darren L. Ficklin, Charlotte Grossiord, Alexandra G. Konings, Jordi Martínez-Vilalta, Walid Sadok, Anna T. Trugman, A. Park Williams, Alexandra J. Wright, John T. Abatzoglou, Matthew P. Dannenberg, Pierre Gentine, Kaiyu Guan, Miriam R. Johnston, Lauren E. L. Lowman, David J. P. Moore, Nate G. McDowell web link The impacts of rising vapour pressure deficit in natural and managed ecosystems – Novick – Plant, Cell & Environment – Wiley Online Library
- “HUMIDITY CONVERSION FORMULAS” by Vaisala Oyj (2013) web link Humidity_Conversion_Formulas_B210973EN-F (hatchability.com)
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“CO2 is innocent but clouds are guilty.”
No exploration of causality here, just correlation. But if the air is warmed, the VPD will increase, until and if increasedsurface evaporation can make up the difference. So CO2 makes fewer clouds.
Our measurements indicate that longwave radiation has increased, not decreased. The current warming trend is indistinguishable from natural warming.
This leaves us with two possibilities: 1) There was an initial decrease in LWR that we failed to measure, followed by feedback mechanisms taking over, or 2) The decrease in clouds is due to a natural source.
The primary support for the first possibility comes from models that are not even capable of accurately simulating clouds in the first place.
“The current warming trend is indistinguishable from natural warming.”
But that test can’t distinguish natural from AGW. It just is a result of warming.
Show us some evidence of AGW in the UAH data. (don’t use the El Nino spike/step)
There is no warming apart from those EL Nino spike/step combos.
As you say, it is impossible to distinguish AGW from natural warming, because AGW is SO SMALL, (if it exists at all)
Just a bs line about warming. What a clown.
The ASR from greenhouse gases on the Earth’s energy budget isn’t a testable hypothesis. Given that natural warming has occurred historically, the burden of proof rests on proponents of AGW.
The abrupt decrease in cloud cover after 1997 tells us it was not a CO₂ feedback.
No Nick, say we add 1 degree to the ocean surface temp (let’s say it is due to CO2 to satisfy your fears)…that will raise the ocean water surface VP by 7%, increasing the number of water molecules above the water surface by 7%…resulting in more buoyant air rising to form 7% more clouds or maybe its only 3.5% more highly reflective lower clouds cuz an equal amount of dry upper air must also fall (which causes more evaporation). So we have a thermal system that is self correcting over the lifetime of a few weather fronts (a couple of weeks) and the rate at which upwelling ocean currents vary and can be heated in the tropics (weeks for surface currents of slightly varying temp to flow from say the Caribbean to Spitzbergen, hundreds of years for deep ocean turnover). Although it is actually the Pacific ocean that controls the planet’s temperature, or rather clouds over the Pacific. CO2 is just a minor player in this, likely about a degree per 2x CO2….The El Nino spikes on UAH an RSS graphs strongly and abruptly show the effect of the variations in Pacific surface temp on the planet average since 1979 and the rest of the upward trend is only about 1/2 a degree…peanuts considering the potential measurement problems.
Agreed, especially with very rapid evaporation and huge cloud formation in the Tropics controlling the planet’s weather.
That evaporation rate is greatly increased by El Niños, as shown by up temp spikes on the UAH graph, updated each month on this site.
CO2, a trace presence in the atmosphere, has a near zero role in this process.
CO2 plays even less of the role elsewhere, especially, in the Antarctic, with near zero WV ppm
From,
https://www.windtaskforce.org/profiles/blogs/natural-forces-cause-periodic-global-warming
https://www.windtaskforce.org/profiles/blogs/hunga-tonga-volcanic-eruption
El Niños
The Heat Source Area provides heat to water of local areas of the Pacific Ocean. That water rises and follows prevailing currents towards South America. That is the normal situation
.
About every 3 – 7 years, increased venting and eruptions take place, due to tectonic plate movements.
That heat warms the already-warm water, and gives additional impetus to El Niños, whose development and consequences are well known.
Very rapid evaporation rates and huge cloud formation in the tropics causes air and WV to rise, and nearby air to fill in the “vacuum”, which causes surface winds and ripples, which causes more evaporation, which causes more surface winds and waves, which causes more evaporation until the 30 C SST limit is reached. This is a mechanically-induced process.
The latest El Niño was augmented by the Hung-Tonga underwater eruption which threw 146 million metric ton of WV into the upper TS and stratosphere, where normally is not much WV.
All that WV is a greenhouse gas which warms the atmosphere, enabling it to hold even more WV, which makes the atmosphere even warmer!
It will take some time, say two to three years, for the unusual situation to unwind itself, to get back to more normal temperatures. See Images 5, 6 and 7
As part of El Niño development, a stream of warm water wells up from the Heat Source Area, departing from there, towards the Peruvian coast. The upwelling weakens the trade winds , which changes air pressure and wind speeds, and push warm water toward the west coast of South America. See Image 11
At higher latitudes, these changes in the tropics allow the Pacific Jet Stream, a narrow current of air flowing from west to east, to be pushed south and spread further east. The jet stream steers weather systems, thereby determining the weather patterns seen across a wide geographic area.
Image 1A: Strong El Niño effects peaking in late-summer/early-fall of 2023
https://ggweather.com/enso/oni.htm
The degree per doubling of CO2 is the hypothetical effect; negative feedbacks will reduce that to something indistinguishable from zero.
No evidence of CO2 warming at all.. no causality, no measurements.
Rate of increase of CO2 is however very closely linked to ocean atmospheric temperature, so CO2 cannot be causing the warming.
“Rate of increase of CO2 is however very closely linked to ocean atmospheric temperature,” BeNasty
Based on ice core estimates, the +1 degree C. warming of oceans since 1850 should increase atmospheric CO2 by 15 to 20ppm with all other variables unchanged
The actual atmospheric CO2 level increased +140 ppm, since 1850 ,.. not 15 to 20 ppm
You remain perpetually ignorant on a wide variety of subjects … and your inane El Nino Nutter comments are appreciated by leftists.
Sorry if basic data and understanding is beyond you.
You are an ignorant know-nothing twit who is totally incapable of backing up anything he says.
Your ignorance and your continued support of the AGW scam is just what alarmists want to see.
And sad little AGW collaborator, just like Nick, Fungal and Luser.
You have been challenged before to explain how CO2 causes cloud reduction everywhere apart from a small region of Antarctica and a few degrees north of the Equator.
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Unless your “greenhouse effect” and CO2 can explain this you are nothing more than a climate zealot who has lost interest in understanding how things actually work. You just believe because that is what you were told to believe making you a religious zealot not interested in understanding the world.
You can understand his position. He ( and others) has a priori decided that Co2 IS the control knob, HAS to be an important factor even though it cant be proven. It is a sign of a true believer..
The many holes/ anomalies in their reasoning as shown by Javier Vinos et al are usually countered by some twisted use of logic. But that makes sense if you consider the desired outcome..
Their reasoning make no sense, even if you consider their outcomes, based on wishful thinking
I disagree. It makes perfect sense. Because if you know the outcome you will manipulate the parameters w unproven assertions or even nonsense. It actually does not have to follow standard reduction and deduction reasoning or basic logical inferences. The ONLY logical inference is that A must lead to B by any means possible..
He won’t answer.
Just correlation.
Same for CO2 being the climate control knob.
But in that case only in highly selective periods. The “CO2 as climate driver” hypothesis must ignore much of the Earth’s inconvenient climate history to appear reasonable.
Cutting sulfur emissions, which seed clouds, seems to be the cause of the reduced clouds.
From the above article’s first paragraph:
“VPD is the difference between the atmospheric saturated water partial pressure, Psw, and the actual water vapor pressure, Pw. It is common knowledge that as VPD approaches zero at any temperature that clouds are likely to form.”
Gee . . . that sounds an awful lot like talking about relative humidity to me. When RH approaches 1, clouds are likely to form. When RH approaches zero, there is hardly any water vapor pressure in the associated atmosphere compared to the maximum it could hold (the “saturation” point) at the given pressure and temperature.
Why do we need to obfuscate scientific terms in this manner?
The attempt was to connect agricultural science and terminology to the climate mysteries.
From the above article’s second paragraph:
“It is common sense that if cloud cover decreases that the earth temperature will increase (assuming all other variables remain constant).”
Well, not really . . . so much for claimed “common sense”! It is commonly known that cloudy skies at night kept the underlying surface and air column warmer than they would be with clear (no clouds) skies. Spend a night under clear skies versus cloudy skies and you can really appreciate the difference.
It is true that clouds are reflectors of downwelling solar radiation during daylight hours, but it is also true that clouds are great absorbers of Earth’s upwelling surface LWIR (which is then thermalized with other atmospheric gases, all of which radiate energy back down to Earth) during both daylight and nighttime hours.
Is it warm at night because of clouds? Or is it cloudy at night because of (advected) warmth?
I’ve slept outside enough to question the assumption that clouds make it warmer. Clouds are typically accompanied by weather fronts. Those weather fronts can do lots of funny things. They can make it colder than expected at night and they can make it warmer than expected at night.
I’m just not convinced that clouds “trap” heat.
Well, Tim, you are correct to question any assumption, but here is a scientific explanation of why ground and air-near-the-ground temperatures are warmer at nighttime with clouds than they would be otherwise without clouds, courtesy of Pennsylvania State University (https://www.weather.gov/source/zhu/ZHU_Training_Page/winds/nighttime_influences/Nighttime_Influences.htm )
with my bold emphasis added:
“. . . an overcast or broken cloud cover, particularly when the clouds are stratus, insures that nighttime surface temperatures will be higher than they otherwise would be. And a clear sky paves the way for a chilly night, assuming light winds. So what’s up with nighttime clouds?
“Clouds emit infrared radiation to the efficiently absorbing ground, keeping the ground (and thus the overlying air) warmer. As a disclaimer, please keep in mind that clouds emit infrared energy in all directions, but, as far as surface-air temperatures are concerned, we’re only interested in the downward direction. Meteorologists sometimes refer to infrared energy that’s emitted downward by clouds (and also the air) as downwelling.
“So clouds are a source of infrared radiation. In this light, think of clouds as “space heaters”, emitting energy toward the ground. In turn-about fair play, the ground emits infrared radiation to absorbing clouds, keeping their bottoms warmer (especially low clouds). In effect, there is a synergy (give-and-take) between clouds and the ground at night. This synergy results in warmer cloud bottoms and, more importantly to us, higher surface-air temperatures.”
Most scientists believe clouds are a positive feedback resulting in more warming, but we really don’t know. “Common sense” is useless in science.
When one understands that water vapor and the hydrologic cycle is the natural moderator of climate and that the other so-called greenhouse gases are red herrings, then one can begin to understand. I believe your excellent work supports this perspective.
Not really.
LWIR active gases (such as water vapor, CO2 and methane), whether on not you want to call them “greenhouse gases”, do act to intercept a significant fraction of the upwelling energy radiated by Earth’s surfaces and to then subsequently distribute that energy (“thermalize” it) with the rest of the atmosphere—predominately nitrogen and oxygen molecules—via extremely rapid molecule-to-molecule collisions and in accordance with Boltzmann statistical mechanics as applied to gas mixtures. That is, that absorbed LWIR energy is distributed to all constituents of the atmosphere . . . it does not reside for even milliseconds solely in the LWIR active gases.
Because all the atmospheric gases have temperatures above absolute zero, they all radiate thermal energy isotropically, meaning that approximately half of that radiation will be directed downward toward Earth’s surface . . . the portion of that returning energy that originated as upwelling LWIR is poorly described as the “greenhouse effect”.
You got the absorption side right. The average thermalization time is about 10 microseconds. At STP, ~99.95% of the absorbed radiation has been converted into sensible heat as you say. Also, as you say, this heat is distributed via collisions and molecular kinetic energies follow a Maxwell-Boltzmann distribution.
Your second paragraph is a common statement of the nature of the “greenhouse effect.” As is often the case, “the devil is in the details.”
This is a short version of what has already been presented by myself and my colleague, Markus Ott on the Tom Nelson podcast and is available also in essay form from Tom Nelson’s substack.
By invoking “thermal radiation” of “GHGs”, climate science has used the radiative transfer model to characterize heat transport through the atmosphere. This is invalid and there will be additional video presentations released soon demonstrating this from both the classical thermodynamic perspective and a quantum perspective.
After the radiation is absorbed and thermalized, the IR active molecules are subject to about 7,000,000,000 collisions per second. As a result of these collisions, a significant
percentage of these molecules are in excited states. In the case of CO2, calculations indicate that is ~7% at STP. For H2O, it is probably higher due to the lower energies threshold and the multiplicity of available states. A small fraction of these excited states will emit a photon in a random direction before they are thermalized again.
The downward directed photons from this process that are detected are perceived as the “back radiation” which is predicted by the radiative transfer model. In fact, they are part of a random flux of photons that play no significant role in energy transport. They are running in “recycled” energy in the competition of thermalization and thermally excited emission. Those that reach the surface can be generated from a source no more than a few meters from the surface.
This competition between thermalization and thermally excited emission continues until the concentration of a particular GHG in the upper atmosphere is low enough for the emitted photons to escape to space. For H2O, this occurs very low in the atmosphere, beginning at 2-3 km. By virtue of opportunity and the multiplicity of available excited states, almost all of the excess energy in the atmosphere is radiated to space by H2O.
For CO2 which is uniformly distributed, the “breakout” of photons occurs near the mesopause at at ~85 km. The peak for CO2 is tiny because there is very little energy left to drive thermally excited emission. The “notch” in the spectrum around the CO2 Q-branch represents the absorption of some of the H2O emissions that overlap the CO2 band. Those CO2 molecules are thermalized again returning that energy to the sensible heat pool
of the atmosphere which continues to drive the H2O emissions.
It’s all about H2O.
Nice, except for:
and
both of which are incorrect.
The emission spectrum of Earth, integrating both surface radiation and atmospheric absorption and radiation, is given in the attached figure and is discussed in detail at this reference:
https://seos-project.eu/earthspectra/earthspectra-c02-p17.html
That spectrum, based on both theory and actual spacecraft measurement, is not representative of the emission spectrum of water vapor. In fact, as pointed out in the referenced article, water vapor (together with CO2 and ozone) is actually blocking a portion of the surface/atmosphere radiation spectrum that would otherwise be escaping to space over the range of 9–25 microns wavelength.
An appeal to the “consensus science” authority is not adequate to refute our claim. The interpretation of the spectrum is incorrect as explained in our essay which is thoroughly referenced.
you can download it at https://tomn.substack.com/api/v1/file/f08770ad-92c4-4884-890b-f969794b1a26.pdf
if you are not willing to even entertain an alternate model, you are part of the consensus. I challenge you to refute what we present.
Really? You foolishly and incorrectly suggest that anywhere in my posts I appeal to “consensus science”? Any reader is free to examine the veracity of what you claim.
Contrary to that, in my most recent reply to you I recommended that you look at the hard scientific data on what the emission spectrum from Earth (at TOA) actually is based on both spacecraft spectrometer measurements and consistent MODTRAN radiative modeling. I reiterate that that spectrum is not at all representative of the emission spectrum of water vapor at any given temperature.
I am indeed willing to look at alternative models that can explain scientific observations, but only if they make sense.
“It doesn’t matter how beautiful your theory is, it doesn’t matter how smart you are. If it doesn’t agree with experiment, if it doesn’t agree with observation, it’s wrong. That’s all there is to it.”
— Richard Feynman
As for your challenge, I have already refuted (via presenting a graph of scientific data and a link to the supporting source and discussion) of your “essay” presentation.
I don’t find it strange that you didn’t take any exception to what that hard data demonstrates in your reply post, other than to call it “consensus science”.
Not really.
From https://earthobservatory.nasa.gov/images/82142/global-patterns-of-carbon-dioxide there is this (with my bold emphasis added):
“The first space-based instrument to independently measure atmospheric carbon dioxide day and night, and under both clear and cloudy conditions over the entire globe, is the Atmospheric Infrared Sounder (AIRS) on NASA’s Aqua satellite.
“The map above {see attached image — TYS} shows carbon dioxide in the mid-troposphere, the part of the atmosphere where most weather occurs. . . .
“The AIRS instrument measures 2,378 different infrared channels, or segments, of infrared light. Carbon dioxide absorbs and emits very specific wavelengths of infrared light, giving it a unique fingerprint. By measuring the emitted thermal infrared radiation, AIRS can detect this fingerprint, giving scientists a way to estimate carbon dioxide concentrations globally.
“AIRS has shown that carbon dioxide is not evenly distributed over the globe; it is patchy with high concentrations in some places and lower concentrations in others.”
So, there we have it . . . a science instrument aboard an orbiting spacecraft directly measuring thermal emissions from atmospheric CO2 at TOA . . . having nothing to do with H2O.
The emissions from the low frequency end of the spectrum that you posted (which is very old) up to the CO2 absorption “notch” are all from H2O and so labeled on the spectrum. If the CO2 was zero, you would see that the water vapor emissions continue and peak around the center of the CO2 Q-branch peak at 15 microns. The “notch” is from CO2 partially absorbing those water vapor emissions. That CO2 is thermalized as well, and the heat returned to the atmospheric pool drives further water vapor emissions. Additional H2O emissions are labeled between 1300-1500/cm at the right end of the spectrum.
if you don’t think that is energy radiated by H2O into space, what do you think it is?
Again, you fail to understand my statements.
I never said or implied that LWIR energy from H2O is not radiated to space. Instead, I provided scientific data supporting the fact that not all energy (at TOA) radiated to space is coming from H2O molecules, thereby refuting your simple statement that “It’s all about H2O.”
BTW, as regards your comment that the spectrum I posted above is “very old”, the Scientific Method does not make any reference as to the age of data being an important consideration in evaluating the merits of a scientific observation. An example for you: Galileo Galilei’s observations of moons orbiting Jupiter, made in 1610 AD, are still considered valid scientific data today, more than 400 years later.
I wouldn’t say “common sense” is useless in science, more like clouds being a “positive feedback” is not “common sense.”
Less cloud cover would lead to more solar energy entering the oceans. That’s more like “common sense.”
It is common sense.
Without clouds, a greater percentage of solar irradiance warms the land and seas. The energy flows into the depths and is stored.
At night, without sunlight, the energy flow is reversed and the land and oceans warm the air.
More energy absorbed and released, warmer air.
It has nothing to do with LWIR. Thermalization is pure BS, that is not how molecular physics work.
IR is not kinetic energy.
Take a moment to mull over the physics of absolute zero.
OK, I mulled over the physics involved (including the real fact that “themalization” does occur in a mixture of gases not at equilibrium, per Boltzmann statistical mechanics) and came away concluding that you overlooked a very simple fact, which I have appended to your sentence here in bold text:
“At night, without sunlight, the energy flow is partially reversed and the land and oceans warm the air and clouds, but the air and clouds warm the Earth by their thermal radiation since they are at a temperature above absolute zero.”
At least you got the reference to absolute zero correct.
I also gently suggest you look up exactly how a molecule that is able to absorb a LWIR photon temporarily stores that energy (which is too low to elevate electron shell levels), and consider that for air in the lower troposphere molecule-to-molecule collisions occur at frequencies 10^6 to 10^9 times faster than an LWIR-excited molecule will emit a photon.
You’re ignoring the additional energy absorbed by the oceans under clear sky conditions. Which has a much greater impact on “climate” given the huge heat capacity of the oceans vs. the comparatively minuscule heat capacity of the atmosphere.
No, I’m not.
Please try to understand that the term “surface” in this sentence in my OP applies to both land and oceans:
“It is commonly known that cloudy skies at night kept the underlying surface and air column warmer than they would be with clear (no clouds) skies.”
and please try to understand that the term “Earth” in this phrase in my OP applies to both land and oceans:
“. . . clouds are great absorbers of Earth’s upwelling surface LWIR (which is then thermalized with other atmospheric gases, all of which radiate energy back down to Earth) during both daylight and nighttime hours.”
And, actually, both (a) the heat capacity of the world’s oceans and (b) the mass of water vapor continuously evaporating into Earth’s atmosphere from the oceans have the effects of smoothing out transients in climate (i.e., making climate more stable than it would be otherwise), so I’m not sure what you are referring to with your phrase “much greater impact on climate”.
Care to clarify?
What happened to Figure 5? I have looked carefully and do not see it.
What on earth is an “increase in climate change.”?
I suspect NASA is up to monkey business
It’s kinda like double-secret probation . . . with apologies to the movie “Animal House” . . . only not.
BTW, chimps could actually do better than the 30+ separate supercomputer models of global climate forecasting consulted by
NASAthe IPCC.This is speculation based on inaccurate data
Which is one small step above junk science.
What data are needed, but does not exist, are
(1) accurate measurements of annual average global absolute humidity for several decades
and
(2) accurate measurement of annual average of global total solar energy blocked by clouds for several decades.
What the present inaccurate data tell us, which could be wrong, because of low data quality is
(1) Increasing absolute humidity from 1980 to 2000
(2) Steady absolute humidity from 2000 to 2020
(3) Declining cloud cover percentage since 2000
Declining cloud cover should lead to warmer days … but so would declining SO2 and other air pollution. There is no way to differentiate between those two potential causes of more absorbed solar radiation.
But most of the warming since 1975 was TMIN, at night (around dawn, or TMIN), which can not be explained my more solar radiation reaching Earth’s surface.
The rising humidity from 1980 to 2000 is contradicted by the steady humidity from 2000 to2020. Those contrary data make it impossible to verify the Clausius–Clapeyron relation ,,, which is the theory used to predict CAGW.
If more sunlight reaches the surface, it warms up and atmospheric water increases. It is clear that water vapour has increased almost globally since global measurement have been available. This is the regional trend across the global oceans since satellites recorded that data:
?ssl=1
The land exhibits similar trends to the adjacent ocean.
More water vapour means reduced transmission of OLR. That means the surface cools slower at night so average temperature is higher. The extra water vapour also absorbs more incoming solar so not all the extra solar makes it to the ground.
I was under the impression that OLR has actually increased. This to balance out the higher surface temperatures. Anyone?
Correct. The OLR has increased but not as much as the OLR has reduced so there is e net imbalance of 1.1W/m^2.
I shouldve added: OLR at the top of the atmosphere which is different from what’s going on in the lower troposphere w clouds. You also have to take into consideration the type of cloud at various altitudes and their effect.
What matters most is the actual TOA OLR if you’re talking about energy balance.
Exactly. And that is what the Chart 10 above shows. The ToA energy imbalance this century to end of 2023. It averages 1.1W/m^2 if you accept the calibration of CERES radiation instruments to the ocean heat content.
Chart 10 is just the energy balance. It is possible to infer the cause is clouds because of the way the OLR and SWR aree inversely correlated.
The value of Chart 10 is that any explanation that relies on the “greenhouse effect” for the energy imbalance has top explain where most latitudes aree doing the reverse of a small region over Antarctica and a sfew latitudes just north of the Equator.
CERES has a stated measurement accuracy of 0.5% to 1.0% and a measurement bandwidth of 99.5%. The CERES brochure does not address linearization, size of the sensor/sensor array, and calibration due to altitude is also limited by GPS accuracies. MIL-GPS is quite good, but not perfect and is yet another source of measurement error.
1.1 W/m^2 is less that the measurement error.
Thanks. Interesting..
“The land exhibits similar trends to the adjacent ocean.”
No it doesn’t – it exhibits the opposite…..
https://acp.copernicus.org/articles/23/6559/2023/#:~:text=A%20reduction%20in%20near%2Dsurface,all%20associated%20with%20global%20warming.
“Abstract
Clouds play a key role in Earth’s energy budget and water cycle. Their response to global warming contributes the largest uncertainty to climate prediction. Here, by performing an empirical orthogonal function analysis on 42 years of reanalysis data of global cloud coverage, we extract an unambiguous trend and El-Niño–Southern-Oscillation-associated modes. The trend mode translates spatially to decreasing trends in cloud coverage over most continents and increasing trends over the tropical and subtropical oceans. A reduction in near-surface relative humidity can explain the decreasing trends in cloud coverage over land. Our results suggest potential stress on the terrestrial water cycle and changes in the energy partition between land and ocean, all associated with global warming.”
The image I posted was covering atmospheric water vapour for oceans and I stated correctly that the land shows similar trends for water vapour. So not sure why you aree bringing clouds into it. It is quite evident that cloud has reduced apart from over a small region of Antarctica and just north of the Equator.
Go fee comments up you will see my Chart 10 showing latitudinal changes in SWR and OLR clearly indicating average cloud reduction resulting in net increase of 1.1W/m^2 globally.
From the abstract..
“Our results suggest…. “ yawn !!!
And the average of the southern hemisphere and the northern hemisphere is legitimate?
Good point, RickWill. Also evaporation tends to keep TMax limited, while nightime Tmin can still be higher due to daytime sunlight, when temperatures at other stations weren’t at Tmax but more area was almost at Tmax.
Accurate data. Hmmm…. measurements on a 25 km grid yields accurate measurements. Got it.
The straight line in most graphs hides that the data has not been changing over time, but presents a discontinuity between 1997 and the early 2000s, a known climatic shift that affected most climate variables. These shifts, like the one in 1976, separate distinct climate regimes where meteorlogical patterns are statistically different. It is one of the ways climate changes naturally.
You do not get a lot of information by studying global averages. This chart shows the latitudes where cloud has reduced and increased, Reducing cloud cover causes a reduction in reflected short wave and a decrease in outgoing long wave.
?ssl=1
Cloud cover has reduced at all latitudes apart from a small region of Antarctica and a small region north of the Equator.
The global difference of 1.1W/m^2 radiation increase in thermalised solar less OLR increase is supposed to be caused by CO2. So how is CO2 reducing cloud cover everywhere except a small region of Antarctica and a few latitudes north of the Equator?
Anyone who believes in a “greenhouse effect” contributing to Earth’s energy balance has to explain why it is so selective in increasing and reducing cloud cover so selectively.
Antarctica has a permanent temperature inversion over most of the continent.
That inversion results in global cooling as the greenhouse gases increase. A few ice shelves and the small peninsula have warming that offset that cooling, for a net flat trend since the 1970s.
If the surface temperature affects cloudiness, then no change is cloudiness is EXPECTED in Antarctica.
Basic climate science thay you obviously did not know.
The alleged changes in cloud percentages elsewhere are too small to be statistically significant, so are meaningless data not fit for conclusions.
It is also a leap of faith to claim the percentage of cloud coverage is a great proxy for total incoming solar energy blocked by clouds
Actual solar energy blocked by clouds data would require measurements of cloud types, cloud heights and cloud timing. Those data do not exist.
It is only an educated guess, not a fact, that a small reduction in the percentage of cloud coverage in the past two decades has caused more solar energy to reach Earth’s surface.
Conclusions about clouds and absolute humidity based on incompetent data are merely scientific speculation, not solid science
“That inversion results in global cooling”
roflmao.. What global cooling ??
Speaking of scientific incompetence.. have you found any empirical scientific evidence of warming by atmospheric CO2 yet ??
Cloud cover over the tropics where warmest part of the Sun’s energy reaches the surface are absolutely anti-correlated to atmospheric temperatures.
The alleged changes in cloud percentages elsewhere are too small to be statistically significant, so are meaningless data not fit for conclusions.
Read the chart. It is a radiation balance NOT CLOUD FRACTIONS.
The chart is not showing cloud fractions. It shows the radiation for SWR and OLR across latitudes. The global average is net uptake of 1.1W/m^2 over this century.
So you claim CO2 is responsible for the increase in SWR and reduction in OLR over Antarctica. So how does the temperature inversion, caused by CO2, work to do the same thing for a few latitudes just north of the Equator but has done the opposite for all other latitudes. No BS on cloud fractions just the radiation imbalance that “greenhouse gasses” are supposed to achieve.
‘Radiation imbalance’ implies a balance. But that balance is never achieved as it is just the system reacting to interactive parameters. And nothing stays the same. So, everything in the system reacts to everything else. Given the small temperatures fluctuations we are talking about it is, as always, nigh on impossible to equate a precise causal relationship if you look at the system as a whole. Anyone claiming such causality should humble his or herself.
To me that is comforting. People often extrapolate a local (or even small effect) to a (often) linear general global process. This ‘radiation imbalance’ is one of those slippery concepts.
Concur.
Touching on extrapolate:
Unfortunately climate modelers have never heard or or ignore Nyquist.
Nyquist-Shannon sampling theory (proven valid) requires a sampling frequency at least twice the signal frequency to be able to reconstruct the signal. Less than 2x and the reconstruction has aliasing that does not reproduce the signal..
Why is this significant? It deals partially with extrapolation.
Consider a sine wave. Start at the cycle minimum and include the curve from the minimum to 1/8 of the cycle. Now extrapolate the upward slope. You do not get a sinewave, You get a “runaway greenhouse effect.”
Basically, the climate modelers are very likely missing underlying signals due to averaging and inadequate sampling.
Considering all conversations about the climate system should be in terms of energy (i.e., joules), the so called radiation imbalance is indeed a slippery slope concept.
This is essence of trendology: throw most of the information away and declare “danger!”.
Cutting sulfur emissions, which seeded clouds, is a major cause of fewer clouds and warming.
https://www.livescience.com/planet-earth/climate-change/cutting-pollution-from-the-shipping-industry-accidentally-increased-global-warming-study-suggests
The article doesn’t mention it but sulfur emissions have also been cut at power plants and other places.
Cutting smog, which reflected sunlight back into space, also has warmed the Earth.
https://e360.yale.edu/features/aerosols-warming-climate-change
Let’s look at SO2 over the USA (estimates from chart)
From 1980.. 180ppb to 1998… 90ppb (essentially halving the SO2 concentration)
UAH USA48 shows no warming
SO2 dropped from 80ppb in 2005 to 20ppb in 2015..
so about 1/4.
According to USCRN and UAH48, there was no warming in US temperature over that period.
Data does not support the conjecture
Drawing a line through that Dubai data in fig 10 has zero statistical meaning…you might as well be doing a best fit through fly specks on a calendar. Thinking one can get meaning from it is hallucinatory.