# A Hard Rain's Gonna Chill

I was re-reading an old post of mine entitled “How Thunderstorms Beat The Heat“. I say “re-reading” because I couldn’t remember writing some parts of it. Yes, it was only from two years ago … but during those two years, I’ve researched and written 83 other scientific posts here at WUWT, plus another 152 political and other posts at my own blog … so things can get lost in the flood.

In any case, I got to thinking about the following graphic from that post. It shows how much evaporative cooling occurs as a result of evaporating the observed amounts of rainfall.

Figure 1. Scatterplot of evaporative cooling versus sea surface temperature. Evaporative cooling is calculated from TRMM satellite-observed rainfall data. Each dot is a 1° latitude x 1° longitude ocean surface gridcell. The conversion factor from rainfall to evaporation is that 80 watts per square metre (W/m2) of solar radiation applied for the period of one year will evaporate one cubic metre of seawater. Thus, one metre of annual rainfall is equivalent to 80 W/m2 of evaporative cooling.

Now, this graph shows the amount of rainfall evaporative cooling, or alternatively the amount of rainfall. I realized that there is an oddity … wherever ocean temperatures average above about 26°C or so, you will get rain. Might get more rain, might get less, but the area in the lower right has very, very few gridcells—not much ocean surface is both hot and rain-free.

I decided to take a closer look at just the tropical data in Figure1, and to show it in terms of the underlying rainfall data rather than evaporative cooling as in Figure 1 above. Figure 2 below shows that result:

Figure 2. Scatterplot of tropical rainfall over the ocean versus tropical sea surface temperature (SST). Each dot is a 1° latitude x 1° longitude tropical ocean surface gridcell.

The oddity is the clearly defined minimum rainfall at the lower right in the graph. For example, the graph says if the average SST of a given gridcell is 28°C, that gridcell will get at least a half metre of rain. Might get more, might get a lot more, but other than a few outliers that is the minimum rainfall you’ll get at an average SST of 28°C.

What does this look like in the real world? Well, here’s the map of the average annual rainfall.

Figure 3. Rainfall data from the TRMM satellite. The satellite only covers the area from 40°N latitude to 40°S latitude. Units are metres of rainfall per year.

You can see the clear evidence of the Inter-Tropical Conversion Zone (ITCZ) thunderstorms and associated tropical downpours just above the Equator in the Atlantic and the Pacific.

Next, Figure 4 shows a detailed temperature map of the warmest areas of the ocean …

Figure 4. Temperatures of the areas of the ocean that average 27°C (81°F) or warmer. Red area above Australia is the “Pacific Warm Pool”

When you compare the two figures, you can see the close relationship between average temperature and average rainfall.

To return to the question at hand, to me the oddity shown in Figure 2 is that there is a minimum rainfall for a given temperature. (There is also a maximum rainfall for a given temperature, following a similar curve, but it is not as well defined).

Not only is there a minimum rainfall for a given temperature, but the slope of the minimum rainfall continues to increase as the average temperature increases. Some experimentation yielded the following heuristic hyperbola (blue line) delineating the minimum temperature.

Figure 5. Same as Figure 2, with the addition of the hyperbola (blue line) which approximates the limit of the minimum values.

This lets us quantify the rate of increase of the minimum rainfall as temperatures warm. It’s shown in the second column in Figure 5 above, headed “Rain Slope”. For example, by the time the sea surface temperature gets up to 27°C, minimum rainfall is increasing at the rate of an additional 146 mm of rainfall per degree C of surface warming.

Finally, let me return to where I started. This was a discussion of evaporative cooling as measured by rainfall. As I mentioned above, a metre of rain per year requires 80 W/m2 over the year to evaporate that amount of precipitation. So we can interconvert between amounts of rain and the equivalent amount of evaporation needed to provide the water for that amount of rain.

As a result of this interconversion ability, Figure 5 also lets us look at how fast evaporative cooling is increasing with each additional degree C of sea surface temperature. This is shown in the third column in Figure 5, headed “Evap Slope”. At 27°C, for example, the cooling is going up by 12 W/m2 per degree C …

One of the results of this relates to the oceanic temperature maximum. It has been noted for some years that in the open ocean, almost nowhere is the average temperature 30°C or greater. You can see this in Figures 4 and 5 above, and I discuss this temperature maximum in a post linked in the endnotes below. Only 1.5% of the individual tropical ocean temperature gridcells shown in Figure 5 are above 29.5°C, and only 0.15% of the gridcells are above 30°C.

To explain the existence of this oceanic temperature maximum, let me suggest that there is plenty of cooling inherent in the minimum rainfall data shown in Figure 5 to put a solid upper limit on ocean temperatures. By the time you get up to 28°C or 29°C, the evaporative cooling is increasing at a remarkable rate. In practice, this means that at ocean temperatures up near 30°C, any extra incoming solar energy merely increases evaporation, with only a minimal increase in the sea surface temperature. This keeps the average sea surface temperature under 30°C everywhere in the open ocean.

Here, we’re in a two-week spell of no rain. It looks as though after a very wet last winter, this winter may be very dry. There’s a technical name for that kind of thing. They call it “weather” …

That’s the downside of that dang weather stuff. I say abolish the environment, it takes up too much room …

The upside of the weather is that it is a lovely calm sunny day today, about 75°F (24°C), with the tiny bit of visible ocean glittering and winking in the far distance. The cat outside the front door gives the peaceful sunshine two thumbs up. Or it would if it had thumbs …

Best of this wonderful life to everyone,

w.

AS ALWAYS: When you comment, please QUOTE THE EXACT WORDS THAT YOU ARE DISCUSSING. This will allow all of us to be clear on exactly what you are talking about.

Data:

TRMM Data is here,  see the bottom of the page for the NetCDF file.

CERES Data is here, I used the EBAF Edition 4.0 dataset.

Further Information on the Ocean Temperature Maximum

Argo and the Ocean Temperature Maximum 2012-02-12

It has been known for some time that the “Pacific Warm Pool”, the area just northeast of Australia, has a maximum temperature. It never gets much warmer than around 30 – 31°C. This has been borne out by the Argo floats. I discussed this in passing in “Jason and the…

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HotScot
February 5, 2018 4:37 pm

Very grateful for all your hard work mate.
Too few people like you around.

Geoff
February 5, 2018 7:27 pm

Gas absorbed in the ocean (mostly CO2) is released above 25 degrees C. The structure of water at the air/water boundary changes at about 28.5 degrees resulting in a dramatic increase in evaporation and the formation of hydrated ions. The open ocean is so large that it would not be possible to heat this “heat sink” above 30 degrees for any significant period of time that would affect our climate. Above 31 degrees the release of CO2 would be dramatic and so would evaporation. It would be interesting to measure the surface water temperature during a very large storm.

Kristi Silber
February 5, 2018 7:42 pm

“Gas absorbed in the ocean (mostly CO2) is released above 25 degrees C”
What do you mean – this is the minimum temp at which it’s released? Doesn’t that depend on other factors besides temp?

TonyL
February 5, 2018 8:54 pm

@ Kristi Silber
CO2 solubility in water has a *huge* temperature dependence.
Water at 0 deg. can hold almost ~2.5 times the amount at 25 deg.

Doesn’t that depend on other factors besides temp?

Of course. But we can say, for the *open* ocean, seawater composition will not change much, otherwise. So the other factors are held largely constant, for any given area.

paqyfelyc
February 6, 2018 6:27 am

You just cannot draw a CO2 solubility versus temperature plot without specifying pH and life content.
Because of this, CO2 content in the ocean (including carbonates) is on average 50x higher than expected by pure solubility/temperature relationship

RWturner
February 6, 2018 7:42 am

That’s also the temperature of the skin of the ocean, not the entire surface waters.

Kristi Silber
February 6, 2018 2:07 pm

TonyL “CO2 solubility in water has a *huge* temperature dependence.”
Yeah, I know. That’s why I was asking what he meant. Seems an odd statement.
paqyfelyc: “CO2 content in the ocean (including carbonates) is on average 50x higher than expected by pure solubility/temperature relationship” Once the CO2 is incorporated in a carbonate the it’s no longer part of the CO2 portion. Perhaps you mean the ocean can “absorb” 50X as much because of its buffering capacity? I dunno, just a suggestion.

dbeyat45
February 9, 2018 1:58 am

Echo that!

Tom Harley
February 5, 2018 4:52 pm

Just last week, Broome on the NW coast of Australia broke a 21 year record for a 24 hour period, when 415mm of rain fell, This brought January’s total to 915mm, not far short of the metre suggested in the post. A year ago in the same spot, December recorded a record 24 hour fall and record month of rainfall. On both occasions I noticed a 1-2C fall in sea temperature, very noticeable at the Broome Port, surrounded by sea on 3 sides, so temperatures are reflective of sea surface temperature. The drop this year was from 30C to 28C on average. I expect Darwin has a similar experience due to monsoonal floods this wet season. A hard rain certainly chills, just like this mornings brief downpour
: http://www.bom.gov.au/wa/observations/waall.shtml?ref=hdr

A C Osborn
February 6, 2018 3:39 am

One problem, 0.7M on the figure 3 globe is Annual and you had it it 1 month.
I do not believe the TRMM data for Australia, especially the northern parts.

Tom Harley
February 6, 2018 4:16 pm

Yes, the January rainfall record of 915 mm for the month is about 1.5 times the annual average!

charles nelson
February 5, 2018 5:09 pm

A key cornerstone of Warmism is its assertion that evaporation is a positive feedback mechanism; because it introduces a potent ‘greenhouse gas’ into the atmosphere. The refusal to accept that Water Vapour plays a key cooling role, is the achilles heel of the entire CAGW hypothesis.
Destroy this aspect of the hypothesis (as Willis does here) and there is very little left to be concerned about.

zazove
February 5, 2018 6:13 pm

Except the “cooling role” in one place is balanced by the moisture-laden winds carrying that energy elsewhere – like towards the poles where it performs a warming role. Evaporation chills one area only to warm another. Not much destroyed there.
Of course it eventually radiates back to space – more and more each year as it happens.

The Original Mike M
February 5, 2018 7:53 pm

“Except the “cooling role” in one place is balanced by the moisture-laden winds carrying that energy elsewhere – like towards the poles where it performs a warming role.”
Not “balanced”. Hot moist air primarily goes up and then loses the heat of evaporation up high above much of the GHG below when is condenses before falling back as cool rain. That heat is physically bypassing a lot of the GHE.
http://cdn.shopify.com/s/files/1/1137/7038/products/DrinkingBird_grande.gif

Hugs
February 5, 2018 11:11 pm

When you get rain in the North, you’re right it gets superhot. Dry -15C turns into snowy -5C, or slushy +2C, or possibly even rainy +10C.
But if it is hot already, like hot as in hot (we consider +25C hot), rain will turn that down to +20C, or +18C, or +15C. On average, rainwater warms up here. But it warms much more the cold winter than anything else.
I’ll tell you something else, about swimming in open waters.
I have a lake close to me. Some people have been complaining that the water temperatures are going up. You’re welcome to test. I’ll offer you accommodation. I can also borrow you an axe so you can remove the solid bits at top and dip in with a thermometer. If you dive to the bottom, the temp will be +4C. It always is. If you consider this too harsh, you can wait for the summer. I can tell you, similarly as Willis noted on tropical oceans, that the lake top 50cm temp usually rises not much over +20C. When it does, it has a strict hard cap at approximately +25C. Why is that?
Because at over +25C the evaporation cools it more than it heats up. Even slight wind eats away all that the Sun inserts in.
There’s your climate panic. Harsh winter turns to a milder one. Adapt.

Brett Keane
February 5, 2018 11:14 pm

Zazove – what Mike M says is what happens. The immense and rapid latent heat transfer to where it can radiate directly, starting at about 5.5km, dwarfs radiation from lower down to the point that ghe is irrelevant at the vey least. Measured, observed, proven. You can see it for yourself if you want, starting above in this post. I have Vulcan crew eyewitnesses to it punching through the tropopause even. Always upward because water vapour is half the density of air, but carries far more energy. Cheers from Brett

charles nelson
February 5, 2018 11:25 pm

zazove…so warm moist air goes towards the arctic in winter…arrives at a place where the temperature is, for argument’s sake….MINUS 20˚C and ‘warms’ that region up to…oh…MINUS 16˚C and turns to snow/ice.
Fascinating insight into the mind of the Warmist.
Thanks for that.

zazove
February 5, 2018 11:56 pm

Mike is right: “Hot moist air primarily goes up and then loses the heat of evaporation up high above…”
The operative word is primarily. Not all of it. I don’t know the proportions but plenty gets mixed with other layers. Eventually…it all radiates back to space. The point I am making is that yes some energy is removed from the tropical ocean surface but that energy get transferred all over the place.

tty
February 6, 2018 12:28 am

“The point I am making is that yes some energy is removed from the tropical ocean surface but that energy get transferred all over the place.”
Very true. It is this heat (and water) transfer from the tropics that keeps most of the Earth habitable. And there is plenty of geological evidence that the heat transfer increases strongly when climate grows warmer. During the Eocene the tropics were hardly warmer than now but there were alligators and cypress swamps on the shores of the Arctic Ocean (which was bathable in summer).

zazove
February 6, 2018 4:03 am

“‘warms’ that region up”
Yes Charles, warms implies warming. Thank you for your insight.

February 6, 2018 4:38 am

The Original Mike M:

Not “balanced”. Hot moist air primarily goes up and then loses the heat of evaporation up high above much of the GHG below when is condenses before falling back as cool rain. That heat is physically bypassing a lot of the GHE.

Brett Keane:

…what Mike M says is what happens. The immense and rapid latent heat transfer to where it can radiate directly, starting at about 5.5km, dwarfs radiation from lower down to the point that ghe is irrelevant at the [very] least. Measured, observed, proven.

PROVEN?? “Now that’s funny right there…”
Then please explain why the exact opposite is actually observed (cold clouds radiates the least energy, warm surface under clear sky radiates the most)

MarkW
February 6, 2018 6:25 am

zazove, most of it gets transferred to space.

paqyfelyc
February 6, 2018 6:59 am

@zazove
“Of course it eventually radiates back to space – more and more each year as it happens.”
If Earth radiates “more and more each year”, this means that
1) it cools down, get colder than before
or (inclusive; any combination thereof)
2) it gets more energy from the sun, i.e. more active Sun, Earth closer to Sun, or smaller albedo
Now, Earth is supposed to heat up, not cool down, so we are told. This means 1 is false.
We have no evidence of a lower albedo, either.
So you basically are claiming that “it is the sun”.
Is that what you meant?

The Original Mike M
February 6, 2018 7:00 am

JKrob: “warm surface under clear sky radiates the most”
Yes but only if it is dry air. Low latitude clear DRY sky at noon is providing the least GHE and therefore the heat will radiate back out the easiest. However that is apples and oranges in the way of the difference of radiation amounts compared to that from latent heat heat transport which does not even raise the temperature of the air at altitude, it holds it a little higher than would it would have been without the condensation. So we aren’t going to be able to ‘see’ a latent heat effect providing maybe an extra 1/10 to 1/2 (?) of a watt on an image showing a range of 100’s of watts per sq. meter.
I do like that image you provided because I consider it to be an dramatic example of how water vapor’s contribution to the GHE is far more dictated by its spatial variation of concentration than by its global averaged concentration. I suspect that that could be central to the failure of the climate models. For example, adding more WV at the places where there is already a high concentration is going to add almost nothing at all to the already high GHE there. On top of that just a small percentage increase of cloud cover from a small increase in water vapor over the wet tropical areas, (as well as the time of day it becomes a cloud per Willis), is going to dwarf the influence by a relatively tiny increase of global average WV.

February 6, 2018 9:30 am

“zazove February 5, 2018 at 11:56 pm
Mike is right: “Hot moist air primarily goes up and then loses the heat of evaporation up high above…”
The operative word is primarily. Not all of it. I don’t know the proportions but plenty gets mixed with other layers. Eventually…it all radiates back to space. The point I am making is that yes some energy is removed from the tropical ocean surface but that energy get transferred all over the place.”

That is known as “waffling”.
First one claims an absolute:

“zazove February 5, 2018 at 6:13 pm
Except the “cooling role” in one place is balanced by the moisture-laden winds carrying that energy elsewhere – like towards the poles where it performs a warming role. Evaporation chills one area only to warm another. Not much destroyed there.
Of course it eventually radiates back to space – more and more each year as it happens”

Then when challenged, one retreats to a very vague nebulous position.
A position that is meaningless.
The zazove puts up a Terra CERES image; without explanation.
It turns out that Terra CERES publish two types of images.
A) Emission spectra
B) Reflected spectra
zazove shows us one of the outgoing emission spectra images. Images that do not specify ground, GHG or atmospheric emissions separately.
Again, what zazove claims above is completely meaningless.
Nor does zazove’s assumption that ground IR emissions means upper atmosphere emissions of not occur have any merit.
e.g. CERES images:

“For scientists to understand climate, they must also determine what drives the changes within the Earth’s radiation balance. From March 2000 to May 2001, CERES measured some of these changes and produced new images that dynamically show heat (or thermal radiation) emitted to space from Earth’s surface and atmosphere (left sphere) and sunlight reflected back to space by the ocean, land, aerosols, and clouds (right sphere).”
Emission colorbar:
Reflected colorbar:

Animated reflected emissions image:
https://ceres.larc.nasa.gov/documents/press_releases/images/ReflectedSolarEnergy.mpg
One final note!
We must keep in mind that information from NOAA is after all information from the current rather untrustworthy NOAA. i.e. an organization that actively tries to prevent inconvenient products from reaching the public.:

“EBAF-Surface Product Features
•Global gridded, monthly mean surface fluxes calculated using a radiative transfer model.”

February 6, 2018 10:42 am

The Original Mike M

Low latitude clear DRY sky at noon is providing the least GHE and therefore the heat will radiate back out the easiest.

Time of day is irrelevant concerning OLWR – the Earth is radiating out 24hrs/day. If anything, greatest potential of reduction would be local midnight-sunrise when temps cool & potential of fog. But even at those times, ground temperatures/fog temperatures are nearly the same – the fog would just reduce the cooling rate due to the latent heat release.
My larger point was to the silly notion deep convection cloud tops are the ‘key’ to large heat release to space – it is actually where the *least* amount of heat/energy is and the CERES imagery (as well as any METSAT IR imagery) proves that.

(as well as the time of day it becomes a cloud per Willis)

\
Heh – too bad satellite imagery says otherwise… If you actually study satellite imagery over the broad tropics, you will find the mid-upper atmosphere dynamics plays a more direct role in cloud cover. You will see areas where there is little to no cloud cover for days (broad sinking/warming air strengthens the trade wind inversion ‘cap’) *or* you will see there is persistent deep convection day/night (broad rising/cooling air weakens/eliminates the trade wind inversion allowing subtle triggers to cause deep convection). His simplistic description of tropical processes (basically, clear morning, clouding mid-day, thunderstorms aftn, clearing night) is unrealistic & incorrect, IMO. Again, satellite imagery says otherwise.

February 6, 2018 10:46 am

Ref. mid-upper atmosphere control of tropical clouds/convection…*NOT* time of day:
The Gálvez-Davison Index (GDI)
http://www.wpc.ncep.noaa.gov/international/gdi/

zazove
February 6, 2018 12:07 pm

paqyfelyc
If Earth radiates “more and more each year”, this means that
1) it cools down, get colder than before
or (inclusive; any combination thereof)
2) it gets more energy from the sun, i.e. more active Sun, Earth closer to Sun, or smaller albedo
Or
3) It is a hotter body because the average temperature has risen. Hotter bodies radiate more energy.

zazove
February 6, 2018 12:12 pm

ATheoK
The first part of your post describes my “waffling”. But the second sequence of waffling (yours) is about someone else’s post:
“The zazove puts up a Terra CERES image; without explanation.”

Alasdair
February 6, 2018 4:08 am

Charles:
I totally agree. The Hydro Cycle is, in fact a Rankine Cycle and transports large amounts of energy from the surface up via the clouds with a proportion reaching the Tropopause in the Cirrus clouds as ice crystals, some 200C above space temperature. This ocurrs oblivious of CO2. and has energy levels an order of magnitude greater than the purported greenhouse effect.
This process provides the global thermostat and has successfully maintained a remarkably stable planetary temperature over millions of years.
In trite terms one might say the the Earth sweats to keep cool, just like you and I.
I have commented on this many times; but nobody seems to come back to me on this. Perhaps this maybe because the concept of the Rankine Cycle is more in the province of the engineers rather than scientists and has been lost to the days of Steam Trains and the like. It is, however it still very much alive and kicking as it continues to generate our power to this day.
True: It does destroy the “Satanicco2 Meme” very effectively and Willis’s article again effectively demonstrates this. My thanks for that.
My regards

charles nelson
February 6, 2018 1:13 pm

Alisdair, l have a great deal of fun making perfectly observations and statements of fact to these people and watching their reactions. I am indeed from an engineering background and sometimes I despair of the ‘scientists’ who confuse and conflate what they observe and cook up theses and hypothesis on that basis.

Kristi Silber
February 6, 2018 2:11 pm

You don’t give scientists credit. They aren’t stupid, you know. This is a topic about which there is much ongoing discussion.
Willis hasn’t destroyed anything. He’s posed a hypothesis that is interesting but not applicable to the real world.

GregK
February 5, 2018 5:11 pm

Great stuff Willis.
A seeming peculiarity of the scatterplot is the uneven distribution of points on the extreme bottom right [Fig 5]. There seem to be some places where rainfall is low and unaffected by rising temperature.
Dodgy data or real?

Kristi Silber
February 6, 2018 2:14 pm

Can you please explain what the pattern on the left in the first graph represents? It’s almost wave-like.

michael hart
February 5, 2018 5:16 pm

I’m still trying to digest what it means when one looks at the variation with latitude. It can’t be coriolis effect because the Northern and Southern hemispheres are different. Wind speed?

michael hart
February 5, 2018 5:19 pm

But, on the other hand, insolation is not symmetrical because the Southern summer gets more intense insolation by, what, 7% to 9%?

michael hart
February 5, 2018 7:37 pm

Willis, my question was driven by looking at the extra-tropical data in figure 1, and noticing an apparent difference. Unfortunately, now I look again in more detail, it appears there are four types of color on the graph, but the legend only indicates three. Are my eyes or monitor deceiving me, or they color-overlaps?

Hugs
February 5, 2018 11:26 pm

Isn’t the South Pole summer a little bit nearer to the Sun than the North pole summer. And night is equally black on both.
I fail to get textbook answers at these morning hours. Insolation as measured on surface is a different thing – which is interesting.

Wim Röst
February 6, 2018 2:34 am

Willis Eschenbach February 5, 2018 at 6:49 pm: “Regarding insolation, the two hemispheres get equal TOTAL amounts of energy”
WR: There seems to be a difference in insolation between the hemispheres because of orbital reasons, I read that several times, for example here:
https://judithcurry.com/2016/02/23/is-sea-level-rise-accelerating/#comment-767110
Turbulent Eddie | February 23, 2016 at 5:35 pm: “So the Arctic insolation peaked about 10,000 years ago, but the latitude of peak insolation anomaly slid continuously southward past the equator to the Southern hemisphere ( which now receives about 6% more insolation than the Northern Hemisphere which used to receive more)”.
WR: Willis, do I understand well that the hemispheres as you say “get equal TOTAL amounts of energy” while in the same time the present orbital constellation results in 6% more insolation for the Southern Hemisphere?
If so, the intriguing question is: what happened with that 6% of extra insolation in the Southern Hemisphere?

Wim Röst
February 6, 2018 10:47 am

OK Willis, clear. Seems quite logic to me. Thanks!

zazove
February 5, 2018 5:23 pm

“In practice, this means that at ocean temperatures up near 30°C, any extra incoming solar energy merely increases evaporation,”
Interesting graphs. This limit would seem to make it less likely for any short-term warming signature to seen in the tropics even though GHGs are reasonably well mixed.

paqyfelyc
February 6, 2018 7:11 am

Indeed, and quite obvious. This made the “tropical hot spot” so relevant, a sort of “Perihelion precession of Mercury” test. Failed, A proper scientist would then trash-bin the theory, instead of trying to find some epicycle to fix it.

zazove
February 6, 2018 12:03 pm

The topic is surface temperatures. Willis’ hypothesis is that evaporation tends to limit temperature rise tropical areas. That limit is not reached away from the tropics. I am not an expert on tropical meteorolgy and I was merely speculating, I am sure there are more robust and concise explanations of why the Arctic has warmed so much more than the tropics.
Rudi

Retired Engineer John
February 5, 2018 5:54 pm

” This keeps the average sea surface temperature under 30°C everywhere in the open ocean.” The 30C limit is also present in lakes that are inland.

Hugs
February 5, 2018 11:30 pm

I wish I’d ever see that! Commented on the same above, but here at 60N 25E the limit appears to be nearer to +25C. However, there are many ways to measure.

tty
February 6, 2018 12:37 am

The Dead Sea does reach 37 degrees in August, but that is at 400 meters below sea-level so the higher air-pressure inhibits evaporation.

Hugs
February 6, 2018 12:52 am

Salty water evaporates less? The place is also as sunny as it gets?

paqyfelyc
February 6, 2018 7:31 am

Salt reduces evaporation.
Lake Assal (Djibouti) is another salty lake in very high temperature climate quoting wikipedia: “52 °C (126 °F) from May to September. Winter temperatures are not low at 34 °C (93 °F) from October to April”
If it wasn’t for the salt, it long would be dry.

Retired Engineer John
February 6, 2018 9:09 am

The Persian Gulf reaches temperatures of 36C; but, it is very salty.

RACookPE1978
Editor
February 6, 2018 11:10 am

Now, what does reduce evaporation is any sort of film on top of the water -even if only one molecule thick. However, If the dissolved chemical “bonds” together between and around the previously separate little water molecules – like a Jello or latex paint or honey – then that chemical would reduce evaporation from the surface.

Toto
February 5, 2018 6:05 pm

“Here, we’re in a two-week spell of no rain.”
Yeah, Seattle took it.
https://4.bp.blogspot.com/-zZ2vY8DB4Sg/Wm_ulczEwlI/AAAAAAAAtyo/lW8ahLqUvqkvGMxrmONmBJgVgoggPHCzwCLcBGAs/s1600/cal%2Brain.tiff
If that link doesn’t work, see the picture at Cliff Mass’s blog:
http://cliffmass.blogspot.com/2018/01/it-never-rains-in-california.html

Hugs
February 5, 2018 11:31 pm

Flash drought TM.

NW sage
February 5, 2018 6:20 pm

Very interesting Willis. Most informative.
Now, since the 30 deg C SST limit observed is strongly related to and caused by the evaporative properties of water, (ie the heat of vaporization), does the pressure at the surface matter? In other words, if the acceleration of gravity were twice what it is now, and the pressure doubled, would that 30 deg limit be changed?

joelobryan
February 5, 2018 8:40 pm

Higher pressure:
It would be a hotter and a lot, lot wetter simply due to lapse rate effects. Something like when the dinosaurs roamed, and for the majority of Earth’s pre-history. Higher atmospheric pressures, not a lot, but enough to raise global temps such that it looked like the higher pCO2 was the culprit to the cargo cultists.

jorgekafkazar
February 5, 2018 10:16 pm

“…However, it does answer the question about why modeling the climate is so !@#\$% difficult …”
Climate models must be easy to make. There are simply dozens of them.
/x

EternalOptimist
February 5, 2018 10:34 pm

Reminds me of the modelling of another complex reactive system in the 70s, 80s, which was military conflict.(using boardgames). One approach was to model the detail, down to the last bullet, the other was to model using abstracts. The first approach( by a company called spi) produced some ridiculous results, the second approach(Avalon hill) got a lot closer to matching history. Of course, what both aproaches taught me was that anyone staking their life on a model was a fool, but they were great for teaching and stimulating interest.

paqyfelyc
February 6, 2018 8:59 am

@EternalOptimist
These games were great for the location management, time to move units depending on the weather and ground, and logistics (supply line matters). “Kriegspielen” (german name) were used by german high command from Napoleonic wars onward, and they DID commit their life to the model. Now, they were no fools, and never claimed this could be used to calculate the outcome of a battle or a war. They KNEW that you never know the enemy situation and moves (“fog of war”), and that unexpected happen for better or worse. This was meant as a a tool to assess the best moves of units with the current known and known unknowns. In that respect, kriegspielen didn’t failed them, but couldn’t prevent their ultimate defeat.
Another thing these war-games were great at was, to show the importance of morale, and the difficulty to simulate it properly. Only games with decent morale management had any chance to bring close to historic battle results.
I wish more people played this kind of game. They would know that computer simulations are just sophisticated boardgames with more rules, and wouldn’t trust computer simulation so much.

tty
February 6, 2018 12:39 am

Higher air pressure slows down evaporation, everything else equal.

paqyfelyc
February 6, 2018 8:29 am

Seems obvious to me that pressure in NOT a commanding variable, but a result of the state of the system.
PV=nRT, so to have double pressure for a given atmosphere composition, you need double temperature (Kelvin — turning the ~288K = 15°C into a ~300°C), and this is just what happens on Venus.
At 300°C, double pressure is not enough to prevent complete evaporation of water

T. Fry
February 5, 2018 6:22 pm

I guess you could say the ocean “sweats”? Maybe not the most accurate analogy, but that’s what my 1-bit brain came up with.
At any rate, I think it’s a really cool analysis (pun intended!).

Kristi Silber
February 5, 2018 7:34 pm

That’s a good analogy. And when one gets hotter, one sweats more – but the evaporation slows with increasing humidity, so if we sweat too much it drips rather than evaporates. Air humidity is a factor in the oceanic vapor flux, too.

Paul Marchand
February 6, 2018 7:29 am

So, could this be summarized as such:
IF CO2 causes significant heating (vs other factors, including geo-solar-magnetism, the decrease of clouds past century due increased sunspots, etc) 1) the heating increases rainfall 2) the rainfall causes warm surface air to rise, which allows heat dispersal into the cosmos 3) the heating causes more clouds, reflecting solar radiation
THUS tempering “anthropological global warming” ?
Also, amazing that Robert Zimmerman / Dylan saw it coming.

Toto
February 5, 2018 6:24 pm

Some of that evaporated water from the warm regions of the Pacific ends up in the Pacific Northwest thanks to atmospheric rivers, aka the Pineapple Express. Here’s another picture from the Cliff Mass blog.
From
http://cliffmass.blogspot.ca/2018/02/an-unusual-heavy-rain-event-on-sunday.html

February 6, 2018 11:31 am

The flip side of the Pacific NW is what we used to term “continentality”. I live within 100km of the geographic center of NA. Any water vapour from the oceans – which is most of it – has to arrive about equidistant from the Pacific, Atlantic/Gulf or Arctic oceans. Only about 400-450mm of precip per year grace our soils. Temperatures, however, are extremely variable at 52N latitude, ranging from -40C to +40C as extremes. The hydrologic cycle rules the climate, and the atmosphere flows freely and rapidly, pushed around by a myriad of forces. Most atmospheric gases are relatively evenly mixed. Water vapour is not.

Myron Mesecke
February 5, 2018 6:29 pm

Off topic and I hope Willis won’t mind too much.
I gagged tonight flipping through channels.
Turner Classic Movies is celebrating Oscar winners and tonight is showing An Inconvenient Truth.

Robert Austin
February 6, 2018 8:17 am

Some day the “An Inconvenient Truth” will be shown as a joke along with “Reefer Madness”.

Kristi Silber
February 5, 2018 6:38 pm

“So we can interconvert between amounts of rain and the equivalent amount of evaporation needed to provide the water for that amount of rain.”
This is not valid since the water vapor doesn’t stay in one place. Think of all the rain that falls inland. Some is cycling through land-based systems, but rivers and aquifer depletion shows that there is loss from that system that is normally replaced from moisture from the ocean.
“In practice, this means that at ocean temperatures up near 30°C, any extra incoming solar energy merely increases evaporation, with only a minimal increase in the sea surface temperature. This keeps the average sea surface temperature under 30°C everywhere in the open ocean.”
Yes indeed. This is, as I’m sure Willis is aware, quite an active area of discussion in climate science: what will happen with the oceanic vapor flux, particularly in the tropics? Will it act as a feedback for warming? A switch? A mitigator? As I understand it, much of the effect of clouds – whether they reflect the sun’s energy or keep it near Earth – depends on their height.
Climate seems so complex to me that it’s hard to comprehend how they could model it. It’s an astounding feat of multidisciplinary, international cooperation. The models are so complex it takes the world’s largest supercomputers days, weeks or months to run them.
They will get better, more precise with less uncertainty, but even the ones now are good enough to identify the most certain forcing agents and the most likely trends. That is what we have to work with in our decision-making.
Or we can choose to do nothing, justifying it by saying that we can’t with complete certainty predict the future. We will do nothing, while the rest of the world acknowledges what is happening and their contribution to the problem, and take responsibility for trying to avoid the worst. It is a shame to our nation! America has dropped her role as a global leader! We now look selfish and self-serving.
Sigh.

jim
February 5, 2018 7:09 pm

‘and take responsibility for trying to avoid the worst’…..sigh indeed! reducing maximum temps and ever so slightly more increasing minimum temps, resulting in ever so slightly increasing average temps, yes, outbreak of horrendous mildness must be avoided at all costs. Don’t you realise how stupid you sound?

joelobryan
February 5, 2018 8:12 pm

Again, an invalid use of the PP.
The PP urges that we strengthen our economy to better adapt and mitigate weather events. and +1.5 K to +2 K of warming is hardly anything but a positive for mankind and the biosphere, considering the positive benefits of more CO2 for plant life.

joelobryan
February 5, 2018 8:20 pm

Kristi’s appeal to PP is invalid/irrational since it is simply an emotional appeal.
The rational appeal considers both any possible benefits from “taking action on climate” (whatever the F that means), and the costs of decarbonizing the economic engines which sustain 7+ billion people.
The costs of decarbonizing, as advocated by the “take action on climate” group, is ignored because it is inconvenient to the “take action” argument by the environmentalists.
But then for the politically Progressive class, “taking action on climate” has always been a Trojan Horse for socialism and power.

Kristi Silber
February 6, 2018 2:37 pm

Joelobryan, what I said is an appeal to ethics. I believe America should take responsibility for our contribution to climate change and work with the rest of the world to mitigate and adapt. I care about our nation and believe our global reputation is of value. If you want to call that emotional, fine, but it is neither irrational nor invalid.
You think you know how every “warmist” thinks, what his political ideology is and ;what he advocates. Now that is irrational.

Alan Tomalty
February 5, 2018 8:20 pm

Pat Frank has proved that all computer climate models are useless for predicting the future. Even the IPCC has admitted that all the climate models “overestimated the temperature increases by significant amounts.” Another folly is that their prediction window of 1.5 to 4.5 C increase is so large a window as to be ludicrous.

Robert of Texas
February 5, 2018 8:28 pm

Why bother modeling it if you have already decided we have to act now to avoid the worse? I really cannot follow such “logic”.
I for one am not convinced warming is bad – it will require human adaptation just like the past 10,000 years have (and likely longer).
I for one am not convinced that the degree of warming is at all alarming. Or the rate of sea level rise. Or the so-called acidification of the ocean. The amount of hyperbole used just makes me learn to ignore the alarmists all together. They appear to think “The End of the World is Nigh!” because of climate. I disagree – climate is going to be the thing that kills a lot of people off – biological agents maybe, but not climate.
I am a computer expert, and I for one am convinced you cannot accurately model the climate system – its just too chaotic (I did not say complex, I said chaotic). If it is chaotic (within boundaries) then all you can do is make some statistical guess and when those are violated by reality, rerun your simulation. You can make some decent guesses if you accept it is self correcting, in which case climate isn’t going to be a problem – because its self correcting. If you look at climate over a geologic timescale, the logic that it is all tied to CO2 is just bizarre.
Sorry if I am seeming to be dismissive of your post, but I just do not agree that we need to take action immediately to prevent something we do not have any understanding of, or any real control over.

Kristi Silber
February 5, 2018 9:04 pm

” The amount of hyperbole used just makes me learn to ignore the alarmists all together. ”
This is a very bad problem. The media has a lot to answer for. I despise Al Gore. You have to realize that these people do not represent what scientists would generally say. Ratings and money come into play, as well as emotion. However, that does not mean that all they talk about is bull, and you are justified in ignoring it. What you and many others like you are doing is being blind and deaf to the risks. It suits your belief that a few degrees warmer within a hundred years is no big deal, but that is simply not the case when you start looking at a wide range of data. The rate is important.
Of course, nothing I say will change anyone’s mind, I know that. But someone has to come to sites like these and inject a differing opinion from someone with a background in science, if only to ruffle the waters of complacency.

Kristi Silber
February 5, 2018 9:17 pm

“Why bother modeling it if you have already decided we have to act now to avoid the worse? I really cannot follow such “logic””
Modeling came before the decision that we should do something – there have been simple models around for several decades. Now and in the future, the results of modeling can help us know how much we should do to achieve a given goal. Lower emissions enough to keep sea levels from rising more than 6″, for example. Uncertainty will decrease, regional changes become better understood, etc., allowing people to plan better. For example, those displaced from coasts and low islands will want to move somewhere that’s not likely to become a desert.
That’s some of the logic, I believe.

A C Osborn
February 6, 2018 5:27 am

Kristi, please provide that “but that is simply not the case when you start looking at a wide range of data. ”
Also you mentioned 6″ of sea level rise, which is 2 bricks on top of a sea wall and decades to add them.
There are Scientists & Engineers from all walks of life on this website, many of whom believed as you do now, but the DATA changed their minds.

Kristi Silber
February 6, 2018 2:50 pm

AC Osborn,
Two bricks on a sea wall would be fine if the world lived behind sea walls and storms never came.
I’m not going to bother providing all the data I take into consideration when it’s not going to make a difference to anyone here. Most of it is readily available and often discussed, and I can’t understand why people won’t take it at face value instead of finding any way possible to try to show it’s meaningless.
What data did the people who were convinced to be skeptical see? I’ve yet to see anything to convince me, and this isn’t the first “skeptic” site I’m been to.
Seems to me that the science is solid enough that people feel they have to discredit the majority of climate scientists in order to maintain their denial.

Kristi Silber
February 5, 2018 8:45 pm

Jim has a point, actually – I’m not sure what happened, but something’s missing, or I didn’t say what I meant to.
(“Yes indeed” looks odd there!) I meant to say that treating complex systems so simplistically and suggesting that this is actually how things work can be pretty misleading, especially when based on a premise equating rainfall with energy transfer due to evaporation. It seems to me it should be noted clearly somewhere that the argument and conclusions are purely hypothetical.
FWIW, I was looking for research into an upper limit of 30 C and found this instead, suggesting there were ocean temps 33-36 C in the past (and they were associated with extinctions).

Alan Tomalty
February 5, 2018 11:11 pm

Kristi the skeptics on this site are just that because they have all asked knowledgeable alarmist scientists just what is the scientific background or proof of AGW or CAGW? And to a fault every alarmist scientist eventually points to the results of the computer forecasting. NOONE and I mean NOONE has yet put forth a cogent reasoned scientific argument that makes any sense or has any empirical evidence to show that AGW exists. It really only exists in the computer models. So us skeptics are reduced to firing shots at the computer models cause the alarmists refuse to debate because they have NOTHING except computer models to back them up. Kristi we welcome you here no matter which side you are on but please go to the article recently about the American Natural History Museum and the letter that 300 scientists have signed and look at their qualifications. After reading that list I think that you would hesitate to bet against their being right.

Brett Keane
February 5, 2018 11:27 pm

Kristi – Models are not validated, therefore they are worse than worthless. Brett

Pompous Git
February 6, 2018 7:51 am

“The current generation of climate models performs horribly at everything but hindcasting global average temperatures…. they are trained and selected on the basis of how well they can hindcast the global average temperature”

They must have improved considerably then since you wrote this:
Testing … testing … is this model powered up?
In that piece you wrote:

“And it is true that for their results to be believable, they don’t need to hindcast the actual temperatures ST, monthly temperature changes ∆ST, and monthly acceleration ∆∆ST.
However, they do need to hindcast believable temperatures, changes, and accelerations. Of these models, only UKMO, and to a much lesser extent M_medres, give results that by this very preliminary set of measures are at all lifelike. It is not believable that the tropics will cool as fast as hindcast by the CM2.1 model (Fig. 3). CM2.1 hindcasts the temperature cooling at three times the maximum observed rate. On the other hand, the GISS-ER model is not believable because it hindcasts the temperature changing at only half the range of changes shown by observation. Using these models in the IPCC projections is extremely bad scientific practice.”

Kristi Silber
February 6, 2018 4:52 pm

As I implied before, climate modeling blows me away. I know the basics of how it’s done, but that’s it. That’s really as much as most laymen can be expected to know.
Much effort and argument has gone into trying to show that climate models are useless. Well, I am more inclined to trust the vast majority of the international climate science community than I am to trust the contrarians, especially those contrarians associated with organizations who push denial and currently or in the past received funding from the fossil fuel industry. That’s my choice, you don’t have to like it or agree. There is incontrovertible evidence for a propaganda campaign funded by FF interests with the goal of making the science seem uselessly uncertain…and it’s been fabulously successful. On other sites I’ve seen outright lies. This one is more subtle and challenging, but there are still plenty of misinformed people around.
If Anthony et al. really want to get at the truth and help the public be able to make informed decisions, how about looking at the current and potential effects of climate change, both costs and benefits? I find that most skeptics have a very limited (or erroneous knowledge of these.
Hind-casting is just one way of testing. Now that they’ve been at it awhile, they can also test how well models do in predicting the future over the course of a decade or two. They can compare models and look for systematic bias. They can change parameters within realistic limits and see if the models remain stable.
Models are not only used for predicting, but for evaluating the major forcing agents.
It’s true that hind-casting is also used in tuning models – but you have to test before you know what to tune, and tuning is perfectly legitimate. It would be silly to test the model, be able to see what was wrong with it, but leave it as is. Fix and test again.
No one is going to argue that the models are perfect, but it’s a mistake to dismiss them as useless. We need to make policy decisions. Are we going to do nothing just because we don’t have a crystal ball with a perfect image of the future, or decide using the imperfect but adequate tools we have?
I see that you tested some models back in 2010. Is this the type of analysis that modelers use for their tests? If not, why not use that instead? To me it doesn’t seem like box plots are a very effective way of evaluating trends, and trends (averages) are after all the desired product of models.
NASA had a nice little blurb about ways of model testing, ending with the following (I suppose many would believe that they are simply lying. I don’t.):
“Climate models are unmatched in their ability to quantify otherwise qualitative hypotheses and generate new ideas that can be tested against observations. The models are far from perfect, but they have successfully captured fundamental aspects of air, ocean, and sea-ice circulations and their variability. They are therefore useful tools for estimating the consequences of humankind’s ongoing and audacious planetary experiment.”
https://www.giss.nasa.gov/research/briefs/schmidt_04/

John F. Hultquist
February 5, 2018 11:07 pm

America is now leading — away from the foolishness of global warming alarmists.
Perhaps you need to re-visit the Paris accord that asked the US to contribute millions while excusing other countries to ramp up their use of coal. Meanwhile, our market economy continues to reduce emissions while Germany with its transition to green energy closes Nuke plants and burns more brown coal. And the UK resists gas in favor of importing America’s forests and claiming it is all waste wood.
Off da! I’m off to do something useful.

February 5, 2018 6:48 pm

The Australian BoM “MetEye” shows the warm pool as 30 – 32C. Cranked up a bit maybe, but I think it has been worse.
http://www.bom.gov.au/australia/meteye/?ref=ftr
“current” sea surface temperature needs to be turned on in the left-side drop-down menu.

Extreme Hiatus
February 5, 2018 7:04 pm

Willis, yet another interesting post. Your combination of common sense and scientific investigation sure produces some ‘ a ha’ moments.
However, you do realize that you are challenging one of the great minds of the 97% Club, don’t you? He’s a PhD and everything!
““The Oceans will begin to boil…” – yes he actually said that, along with some other silly things.”
https://wattsupwiththat.com/2012/01/12/quote-of-the-week-dr-james-hansen-of-nasa-giss-unhinged/

Pop Piasa
February 5, 2018 7:17 pm

Thanks, Willis. It really does seem to be the water on the planet that regulates the temperature so beautifully. Even the troposphere is modulated by water vapor and the teleconnections between SSTs and atmospheric pressures and jets in both hemispheres. This helps in the understanding of the Madden-Julian Oscillation and Southern Oscillation Index, too.

Frank
February 5, 2018 7:33 pm

Willis wrote: “As a result of this interconversion ability, Figure 5 also lets us look at how fast evaporative cooling is increasing with each additional degree C of sea surface temperature.”
There are some very interesting observations in the post, but they may not have anything to do with a cause-and-effect between temperature and evaporation.
1) Precipitation and temperature change from season to season. In the tropics, the ITCZ moves north and south. If there were a cause and effect relationship between temperature and evaporation, it would be better to examine monthly data, not annual averages.
2) Water vapor remains in the air an average of 9 days between evaporation and condensation. That figure comes from the total column water vapor divided by average daily precipitation. In the tropics, the average is about 5 days. A typical speed for a trade wind is about 7 m/s or 600 km/day. So the average water molecule in the tropics travels something like 3600 km between the location where it evaporates and the location where it falls. That is about 10% of the way around the world. So your scatterplots showing the relationship between annual average rainfall and annual average temperature probably don’t tell us anything reliable about the relationship between local evaporation and local temperature. Precipitation is caused by rising air. Air may rise the most where it is warmest.
3) The rate of evaporation (evaporative cooling) is known to be proportional to wind speed and undersaturation (1 – relative humidity) of the air over the ocean. Temperature only enters the picture via its effect on undersaturation. The greatest undersaturation occurs where dry subsiding air from the free troposphere mixes with the moist boundary layer.
The relationships you observed in this post are extremely intriguing, but mechanistically unlikely to reflect a cause-and-effect relationship.

Kristi Silber
February 5, 2018 7:47 pm

Thank you. Nice post. Interesting.

TonyL
February 5, 2018 8:22 pm

but mechanistically unlikely to reflect a cause-and-effect relationship.

It’s a big world out there, and a complicated one.
I try not to put too fine a point on things like this. I would to prefer to think of it as a mechanistically sound relationship, just a bit *geographically stretched*.
A dwell time of 5 days in the tropics??? Perhaps 10 days in the dry season, averaged with 1 day in the rainy season? But all the action is in the rainy season.

That figure comes from the total column water vapor divided by average daily precipitation.

OK, the definition is fair enough.
Hypothetically:
Suppose the humidity is 50% in the morning, shoots up to 100% in the afternoon, and then rains buckets with humidity dropping back down to 50% for the night.
Do we say the dwell time is 2 days because half the moisture content rained out that day? Or should we say the dwell time is 1 day because all the moisture that went into the air came right back out?
Why, oh why, does my schedule dictate that that my dream Caribbean vacation *always* happens right smack in the middle of the Rainy Season.

Hugs
February 6, 2018 1:07 am

Your comment is interesting no doubt. I think hourly, daily, monthly and yearly divisions all reveal different aspects on how clouds emerge and are partly a reaction to the sea surface temp.

Frank
February 7, 2018 6:26 am

I agree. However, WIllis’ thermosta hypothesis operates on a daily time scale. These annual averages are totally disconnected the mechanistic details of what happens on a daily time scale – such as the fact that the average water molecule remains in the air for nine days (global average) and five days (tropical average).

Randy Bork
February 6, 2018 7:00 am

Frank – wouldn’t your point #2 above lead you to expect the scatter plots in Figs 1,2 and 5 to just be a random scatter and show no association of sea surface temp to the dependant variable?

Frank
February 7, 2018 6:22 am

Randy asked: “Frank – wouldn’t your point #2 above lead you to expect the scatter plots in Figs 1,2 and 5 to just be a random scatter and show no association of sea surface temp to the dependant variable?”
Great question! To oversimplify a bit, rain is falling where air masses are rising. Wills is showing us scatter plots of annual averages of temperature and annual rainfall. There is certainly some correlation between annual average temperature and frequency of rising air. To the extent that winds blow mostly east/west, evaporated water will tend to fall at the same latitude it evaporated. Temperature varies with latitude too. So one shouldn’t expect a random plot.
What Willis is selling in this and many other posts is the thermostat hypothesis: evaporation limits maximum temperature (and could do so despite rising GHGs). The situation is far more complicated that Willis suggests, but some elements of the simple picture he presents are probably valid. However – strange as it may seem – it is a FACT that the rate of evaporation is controlled by undersaturation (1-RH) and wind speed – not temperature. Wind speed controls the turbulent mixing that vertically transfers water vapor from the air near the water’s surface to the rest of the boundary layer. The relative humidity of the boundary layer controls the rate at which water molecules enter the ocean from the air. When relative humidity is 100%, water vapor from the air are returning to the ocean as fast as they are evaporating.
Air becomes undersaturated by rising until it is cold enough to rain. Air rises because of an unstable lapse rate, which develops because radiative cooling doesn’t let enough heat escape as thermal IR as fast as it arrives from the sun.
IF evaporation increased at 7%/K (as saturation vapor pressure does), 5.6 W/m2/K more latent heat would leave the surface of the Earth as it warmed. A gray body at 288 K and emissivity of 0.61 emits only 3.3 W/m2/K as it warms and that produces a no-feedbacks climate sensitivity of 1.1 K. If ECS were 1.8 K or 3.7 K due to positive feedback, only 2 or 1 W/m2/K of heat leaves the TOA for space as the planet warms. If so, the rate of upward convection of water vapor must slow, causing precipitation to rise perhaps 2%/K (instead of 7%/K). In that case, relative humidity will rise over the ocean and suppress evaporation. This process – not the simple concepts Willis is selling – determines ECS and the response to rising GHGs. There is no reason to believe that the IPCC models get these processes right – and the clouds that go along with them (which are even more critical).
For good mechanistic reasons, there is no reason to believe the thermostat hypothesis either. Tropical thunderstorms do limit daytime warming over tropical islands that warm faster than the ocean. However, that happens only over islands. Over the open ocean, it actually rains somewhat more in the hours before dawn than in the late afternoon. (:)) Which is not surprising, since SSTs rise less than 1 degC each day (see WIllis’s recent post) while land might warm 10 degC. Rain at night is caused by radiative cooling of cloud tops at night.

Loren Wilson
February 5, 2018 7:46 pm

Looking at the two maps, the few locations with surface temperatures above 30°C but little rainfall could be explained by areas like the Persian Gulf and the Red Sea. These waters are hot but not much rain due to the surroundings. Isolated, narrow bodies of water in temperate or tropical regions evaporate quickly (hence the high salinity of the Red Sea) but since the air around them is extremely dry, the air is not sufficiently humidified to produce the conditions of cloud formation and precipitation.

Thomas
February 5, 2018 7:54 pm

Willis,
They are fascinating graphs.
The large blue areas over the oceans in figure 3 show the oceanic deserts, where little rain falls; about the same as the great land deserts like the Sahara. However, in the oceanic deserts much evaporation occurs. Hadley cells carry this moisture-laden air to the ITCZ where convection causes it to from clouds, then fall as rain.
I don’t see how the information you have presented informs the AGW debate. Average global temperature, and it’s anomaly, are really a proxy for global energy content. The energy content of atmospheric air is expresses as enthalpy (in BTU/lb or KJ/kg). Enthalpy includes the sensible heat in the air, which we read from a thermometer, and the latent heat which is a function of the water vapor content of the air. When water evaporates in air, the temperature of the air is reduced but the total heat content is constant—it’s an adiabatic process, i.e. no change in total energy.
This means that a spring day in Florida, with a temperature of, say, 85 °F can have the same total energy content as air in Arizona that has a sensible temperature of 110 °F. Hence the fact that global air temperature is a proxy for heat content. If the average temperature increase, more water evaporates (on average), so the enthalpy is (on average) about the same for any given average global temperature.
I don’t know that to be true but, if it’s not true, the use a global average temperature anomaly as a measure of AGW is falsified. But it does seem like a reasonable assumption.
Evaporating water reduces air temperature but total heat content (enthalpy) is unchanged so evaporation cannot overcome the heat that is added by the greenhouse effect of, for example, human CO2 emissions.
More clouds would reflect more solar radiation, which could counter balance greenhouse gas warming. The IPCC admits that we don’t know either the magnitude or the sign of the cloud feedback. I think it must be, overall, a negative feedback because the earth is cool and the sun is hot.

joelobryan
February 5, 2018 8:29 pm

“so evaporation cannot overcome the heat that is added by the greenhouse effect of, for example, human CO2 emissions. ”
That is a misdirection. Evaproation moves heat from the SS to the upper troposhere wher condensation release the latent heat back to sensible heat at a much lower temperature. Work is done in the process.
Much of that sensible heat (now IR energy) is above the 8 km effective Radiation Level and easily escapes to space.
This is the bugaboo that the modellers must parameterize. It is why the models are junk science. The modellers can tune the outputs to meet expectation because the convective and vapor vapor parameters are so poorly constrained by observation no one knows why one sets of parameters would be better than another. So the only thing they tune for are precipitation rates and a CO2 sensitivity.

joelobryan
February 5, 2018 8:36 pm

And then they “calibrate” parameters based on expectations in short calibration runs of individual modules. And then they “validate” only by comparing to other models. Pure cargo cult science.
Willis’s work is one of working with observations. The observations shows that the complexity of the evap/prcip problem is immense and the uncertainties in our understanding is even greater.
And yet Climate Science is settled on what the models say according to “cliamte science.” That’s Pure religion.

Randy Bork
February 6, 2018 7:22 am

Joel, you say “Evaporation moves heat from the SS to the upper troposphere where condensation release the latent heat back to sensible heat at a much lower temperature. Work is done in the process. Much of that sensible heat (now IR energy) is above the 8 km effective Radiation Level and easily escapes to space.” Willis’s posts have long made me wonder about this. I followed Willis’s link to the CERES data to see if there was some way the see that in the data. I don’t think I can say I found out one way or the other [should I be looking at CRE or TOA CRE LW or Cloud Effective temp etc…?]. If there is there might at least be some constraints for those parameters you mentioned. [The data I looked at was monthly average so the process you describe might not ‘show’ at that temporal resolution]. https://ceres-tool.larc.nasa.gov/ord-tool/srbavg

Alan Tomalty
February 5, 2018 9:54 pm

As I understand it, any evaporation needs heat to break the water molecule bonds. This heat is mostly supplied by the sun on the oceans surface. The air also supplys heat but most of the heat comes from the sun. As the oceans surface gets hotter from the suns rays, the water surface molecules evaporate into the troposphere and eventually some water vapour (through convection) gets into the stratosphere as well. When the water evaporates from the sea surface, the air also loses a small amount of heat that is then turned into latent heat so the tropospheric air gets cooler. However as noted above most of the heat required for evaporation comes from the sun. The sea surface water then gets cooler as it loses heat through the latent heat process of evaporation. So evaporation weirdly causes both the sea water to cool and the surrounding air to cool. It is interesting that some meteorologists get that wrong. When the air collects too much water vapour there will be condensation when the dew point is reached. That dew point (% moisture by volume of H2O) rises in a parabolic line as temperature increases. Since all the H2O simply recycles itself total evaporation equals total condensation as Willis has pointed out. An important argument seems to be what is the % importance of sea surface temp vs air temp as to the average % of which heat that is turned into latent heat (sea water heat or air heat) ? Also what happens to the latent heat in the water molecules in the air after evaporation ? If that latent heat simply was returned to the oceans by condensation then the oceans would boil over eventually. So it must escape. It must radiate out of the water molecules before condensing to rain or snow. This is the smoking gun of the AGW debate. Since there is an average of 20000 ppm ( in some places a limit of 180000 ppm) by volume of H2O ( water vapour) in the tropopshere compared to 400 ppm of CO2 that represents a 50 to 1 ratio. Dont forget that H2O( water vapour) and CO2 are both about equal as “greenhouse gas heat absorbers”.The alarmists are trying to tell us that even though CO2 is outnumbered 50 to 1 it is responsible for increasing the temperature enough so that more water vapour is formed. As noted above it is the sun that creates most of the evaporation NOT the heat of the troposphere. Even if the CO2 was increased to over 20000 ppm the same as the H2O(water vapour) it would still be the sun that would cause most of the evaporation. So the alarmists are trying to tell us that even though the CO2 in the troposphere has only increased by 43% since 1950 it is now more important than water vapour. The total increase of CO2 in the troposphere since 1950 is less than the variability of the water vapour in the troposphere in one day on the earth. I ask where is the science behind AGW not to mention where is the science behind catastrophic AGW? I say it is all Bunk. ****************************************************

Alan Tomalty
February 6, 2018 12:19 am

Another light bulb went on in my head. If the latent heat that is absorbed by the water molecules in evaporation is IR and from what I have read that is the case then wouldnt some of the (H2O water vapour) absorbing bands be already filled on evaporation? if that is the case then maybe water vapour isnt such a great greenhouse gas after all? Dont forget that the alarmists depend on the CO2 making the atmosphere warm enough to cause more evaporation and thus more IR absorption from the runaway increase in water vapour that is formed. The alarmists depend on H2O to provide most of the IR heat absorption. If that is not the case then their whole theory is kaput. It is kaput anyway for the reasons I stated in the above post but this seems to be another nail in the AGW coffin. Has there been any measurements of real life heat absorption of water vapour compared to CO2?. I was always under the impression that they were equal in IR absorption capability. Is it possible that tests were carried out in the lab and thus not applicable to the outdoor process of the sun supplying the heat for the seawater and thus the latent heat for the evaporation. Are we sure that H2O water vapour from ocean evaporation has the same IR absorption capability as water vapour produced in the lab which I assume is how scientists have measured the water vapour heat absorption capability up to now? Maybe there is such a thing as virgin water vapour produced in the lab versus real life water vapour produced from evaporation from the ocean. If this line of reasoning is correct then real life water water is not as greenhousy as everyone thought and thus the AGW pillar crumbles.

Alan Tomalty
February 6, 2018 12:21 am

My last line should have read water vapour NOT water water

Toneb
February 6, 2018 12:55 am

” It is interesting that some meteorologists get that wrong. ”
No, it is interesting how some peeps think they know better than the experts, while having zero exptertise themselves.
Observed daily on here.
There is a certain sydrome that names that.
“Even if the CO2 was increased to over 20000 ppm the same as the H2O(water vapour) it would still be the sun that would cause most of the evaporation.”
And no one is disputing that …. however you are doing the classic the “GHE cannot heat” thing. it cant, but it DOES reduce cooling.
By reducing cooling at the sea-surface the GHE creates a lower temp gradient between the ocean a few mils below, thereby reducing the heat flux to the ocean skin, and hence to the atmosphere and space.
“So the alarmists are trying to tell us that even though the CO2 in the troposphere has only increased by 43% since 1950 it is now more important than water vapour. ”
No, what they are saying is that CO2 is acting in addition to WV in the parts of the atmosphere where WV is less prevalent, such as over the Arctic, in deserts and higher up. But also in increasing OHC via the method above.
“The total increase of CO2 in the troposphere since 1950 is less than the variability of the water vapour in the troposphere in one day on the earth.”
Irrelevant, as CO2 does not condense and as a background forcing, is steadily increasing, whereas WV’s forcing because it condenses out, has a quasi-steady GHE.
Finally may I refer you to our host …..
https://wattsupwiththat.com/2018/02/04/the-fantasy-of-accelerating-sea-level-rise-just-got-hosed/#comment-2734414
“….. Bottom line, there is a greenhouse effect, and yes there’s problems with it. The biggest is that over 30 years, science has not been able to pin down the value of climate sensitivity. That’s really the only science argument worth having.
Don’t take this as an invitation to reply with a rebuttal.”

A C Osborn
February 6, 2018 6:01 am

Toneb, can I just point out a slight mistake that you have made?
You said “No, what they are saying is that CO2 is acting in addition to WV in the parts of the atmosphere where WV is less prevalent, such as over the Arctic, in deserts and higher up.”
The “in Deserts” part is the clearest indicator that CO2 does very very little to retard the heat escaping to space, the “Dry” Deserts in particular have the Highest daytime Temperatures and at the same time some of the lowest Nighttime Temperatures.
So CO2 allows maximum heat that has built up all day to escape at night, whereas H2O maintains a much more even temperature.
So you should not have included it.

Alan Tomalty
February 6, 2018 7:42 am

“By reducing cooling at the sea-surface the GHE creates a lower temp gradient between the ocean a few mils below, thereby reducing the heat flux to the ocean skin, and hence to the atmosphere and space.” Toneb
Toneb Now I realize that you just make up stuff as you go along. Your comment did not provide any counter to my arguments. The above sentence is garbage and no self respecting scientist would ever repeat it. I can point you to at least 1 website where a meteorologist has got the latent heat equation wrong.
“Irrelevant, as CO2 does not condense and as a background forcing, is steadily increasing, whereas WV’s forcing because it condenses out, has a quasi-steady GHE.” Toneb
The above sentence is more garbage.
“No, what they are saying is that CO2 is acting in addition to WV in the parts of the atmosphere where WV is less prevalent, such as over the Arctic, in deserts and higher up. But also in increasing OHC via the method above.” Toneb
The above sentence is even more garbage. Toneb you don’t understand averages apparently. You better stick to defending your computer models cause they are the only thing alarmists really have to back them up. However as Dr. Pat Frank has proved the models are garbage as well. Also Willis has pointed out that the only thing that the models do well is back reproduce previous warming or cooling and that is because the climate model programmers tune their programs to reproduce previous temperatures in the recent past. They have no ability to predict future temperatures accurately. It is easy to back reproduce a temperature if you already know the result. However the climate modellers limit their back reproduction to only very recent past because when they try to finetune for ancient past temperatures they screw up the model prediction for future temperature which is already bad enough. So I guess what they will attempt to do is to split up the program into stepped temperature eras where they fudge each ancient temperature era separately. A useless exercise.

Toneb
February 6, 2018 8:35 am

“The “in Deserts” part is the clearest indicator that CO2 does very very little to retard the heat escaping to space, the “Dry” Deserts in particular have the Highest daytime Temperatures and at the same time some of the lowest Nighttime Temperatures.
So CO2 allows maximum heat that has built up all day to escape at night, whereas H2O maintains a much more even temperature.”
Sorry but you need apply meteorology to the analysis of diurnal temperatures in deserts.
They have the highest temperature because they exist in regions of atmospheric descent beneath the sub-equatorial jets (~30deg N/S).
Subsidence within the overlying airmass warms at a rate greater rate than LWIR cooling as it descends and as such a subsidence inversion forms that caps off convection, allowing the surface air to heat. I addition the surface air is dry so a rising air parcel cools at the DALR and not the lesser rate of the SALR, and is therefor not as bouyant.
This is the opposite of the moist equatorial zones which are cooled because thay have a neutral LR and moist convection can cool.
I will look for a tephigram (skewlogT) to demonstrate air overlying desert.

Toneb
February 6, 2018 9:10 am

Just to complete the picture – at night deserts cool quick because the soil is dry/sandy (excellent insuator to the heat flux in the ground).
The air is still, dry, and the skies clear.
So a surface inversion forms underlying the warm air aloft.
Come sunrise this “wedge” of cooled air (maybe only ~100ft deep) is rapidly warmed out.
This is an graphic showing a X-section through a Hadley cell….
And this an upper-air sounding for KNKX, an airport 3ml north of San Diego taken at 12Z on 6th Feb 2018…
http://weather.rap.ucar.edu/upper/nkx.gif
Shows the anticyclonic subsidence and the surface inversion.
Surface air (1000mb) at that time would warm from 12C to 30C rapidly (however this ascent shows fog/stratus which first needs to be burned-off) under diurnal heating and rise up the dry adiabat (orange hatched line) no further than 900mb (3000ft) as it would still be dry. If it arrived there saturated it would then rise up the saturated adiabat (green hatched line) all the way up to 200mb (39000ft).

Toneb
February 6, 2018 9:22 am

“Toneb Now I realize that you just make up stuff as you go along. Your comment did not provide any counter to my arguments. The above sentence is garbage and no self respecting scientist would ever repeat it. I can point you to at least 1 website where a meteorologist has got the latent heat equation wrong.”
Yes, I spent 32 yeas in the UKMO, the last 20 of them as an on-the-bench forecaster briefing amongst others, jet pilots flying £50m jets …. “just making stuff up”.
Like I said – this place is full of non-experts who “know” more than real experts.
It’s called the D-K syndrome actually. Dunning-Kruger.
I am a (retired) meteorologist.
Who/what are you?
(Does that we mean ignore everyone who doesn’t have a related science degree? Then lets ignore Alfred Wegener’s contribution to Geology) MOD

Toneb
February 6, 2018 9:28 am

Alan, the sum total of your “scientific” criticism of my post …
“The above sentence is more garbage.”
“The above sentence is even more garbage. Toneb you don’t understand averages apparently. You better stick to defending your computer models cause they are the only thing alarmists really have to back them up.”
Would you like to try with some linked peer-reviewed science (and not sky-dragon slaying stuff from the likes of notrickszone or some other Blog).
No, because there isn’t any, which is why Anthony says (AGAIN) ….
https://wattsupwiththat.com/2018/02/04/the-fantasy-of-accelerating-sea-level-rise-just-got-hosed/#comment-2734414
“….. Bottom line, there is a greenhouse effect, and yes there’s problems with it. The biggest is that over 30 years, science has not been able to pin down the value of climate sensitivity. That’s really the only science argument worth having.
Don’t take this as an invitation to reply with a rebuttal.”

Toneb
February 6, 2018 9:37 am

“(Does that we mean ignore everyone who doesn’t have a related science degree? Then lets ignore Alfred Wegener’s contribution to Geology) MOD”
Obviously not.
But it’s much harder now than in Wenener’s time

Editor
February 6, 2018 10:49 am

“(Does that we mean ignore everyone who doesn’t have a related science degree? Then lets ignore Alfred Wegener’s contribution to Geology) MOD”
Tone writes,
“Obviously not.
But it’s much harder now than in Wenener’s time”
Why should it be harder now especially when so many degreed scientists these days are publishing gobs of junk science papers?
Retraction Watch:
http://retractionwatch.com/
Dr. Mann posted a junk science paper that got undeserved attention that was later exposed as having fatal flaws, one that most don’t people even know now what the biggest one is.
Rachel Carson and her long debunked DDT attack, she was a scientist with a degree who was shown to be more than wrong, it was JUNK SCIENCE!
Do you know who Milton Humason is?
“Humason dropped out of school and had no formal education past the age of 14. Because he loved the mountains, and Mount Wilson in particular, he became a “mule skinner” taking materials and equipment up the mountain while Mount Wilson Observatory was being built. In 1917, after a short stint on a ranch in La Verne, he became a janitor at the observatory. Out of sheer interest, he volunteered to be a night assistant at the observatory. His technical skill and quiet manner made him a favorite on the mountain. Recognizing his talent, in 1919, George Ellery Hale made him a Mt. Wilson staff member. This was unprecedented, as Humason did not have a Ph.D., or even a high school diploma. He soon proved Hale’s judgment correct, as he made several key observational discoveries. He became known as a meticulous observer, obtaining photographs and difficult spectrograms of faint galaxies. His observations played a major role in the development of physical cosmology, including assisting Edwin Hubble in formulating Hubble’s law. In 1950 he earned a D.Sc. from Lund University.[1] He retired in 1957.”
https://en.wikipedia.org/wiki/Milton_L._Humason
He didn’t have a High School diploma when he made significant discoveries that degreed holders didn’t notice.
“After his family moved to Burdett, Kansas in 1922, Tombaugh’s plans for attending college were frustrated when a hailstorm ruined his family’s farm crops.[2] Starting in 1926, he built several telescopes with lenses and mirrors by himself.[2] To better test his telescope mirrors, Tombaugh, with just a pick and shovel, dug a pit 24 feet long, 8 feet deep, and 7 feet wide. This provided a constant air temperature, free of air currents, and was also used by the family as a root cellar and emergency shelter.[3] He sent drawings of Jupiter and Mars to the Lowell Observatory, at Flagstaff, Arizona which offered him a job.[4] Tombaugh worked there from 1929 to 1945.
Following his discovery of Pluto, Tombaugh earned bachelor’s and master’s degrees in astronomy from the University of Kansas in 1936 and 1938.[2] During World War II he taught naval personnel navigation at Northern Arizona University.[2] He worked at White Sands Missile Range in the early 1950s, and taught astronomy at New Mexico State University from 1955 until his retirement in 1973.”
https://en.wikipedia.org/wiki/Clyde_Tombaugh
“Edison only attended school for a few months and was instead taught by his mother.[8] Much of his education came from reading R.G. Parker’s School of Natural Philosophy and The Cooper Union for the Advancement of Science and Art.”
https://en.wikipedia.org/wiki/Thomas_Edison
I can go on and on…..
Snicker……..

February 6, 2018 11:10 am

Toneb – WOW someone who *actually* understands meteorology!!!
These armchair weathermen with a physics book on their bookshelf but think they have full operational knowledge of atmospheric kinematics/thermodynamics are getting rather tiresome :-/

Editor
February 6, 2018 11:30 am

Jkrob,
Retraction Watch:
http://retractionwatch.com/
There are a lot of degreed scientists posting junk science.
You wrote,
“Toneb – WOW someone who *actually* understands meteorology!!!
These armchair weathermen with a physics book on their bookshelf but think they have full operational knowledge of atmospheric kinematics/thermodynamics are getting rather tiresome :-/”
I get tired of SNOBS like you and others, who feel the need to knock down those who may not have that big science degree sticking out of their back pocket, do not see things the way you do.
Want to discuss …. he he he , David Appel, who has a PHD in Physics………?
Want to discuss DOCTOR Jeff Masters, who is deep into the AGW delusion?
Stop being a SNOB!

February 6, 2018 3:52 pm

Sunsettommy,
(sigh…) whether you have a degree or not is irrelevant. What you post in this blog shows your knowledge. As Ronald Reagan said; “It’s not that some people don’t know alot, it’s what they know is wrong”. If people on here post incorrect information with nothing to back up their claims, and others with much more knowledge point out their errors with references to back up their claims but the person in the wrong is unwilling to be corrected, that is their problem, not mine.
BTW – just because a person may have a physics degree does not make them a meteorologist any more that being a geologist makes them a horticulturalist. They both deal with dirt but horticulturalist are specialists in the same way meteorology deals with physics but meteorologists are specialists in that area.

Editor
February 6, 2018 4:49 pm

JKrob writes,
“If people on here post incorrect information with nothing to back up their claims, and others with much more knowledge point out their errors with references to back up their claims but the person in the wrong is unwilling to be corrected, that is their problem, not mine.”
A reasonable statement, however how would you know that having more knowledge will make the difference? They can still be wrong for other reasons, such as ideology, confirmation bias, and more.
Thomas Edison didn’t have much formal education at all, Neither did Abraham Lincoln nor Andrew Johnson and so on, yet they manage to have a big impact anyway despite not having much native knowledge.
You made this comment without merit since it was a base snob comment, same with Toneb who has been strongly disputed by others with science degrees here on this blog.
“Toneb – WOW someone who *actually* understands meteorology!!!
These armchair weathermen with a physics book on their bookshelf but think they have full operational knowledge of atmospheric kinematics/thermodynamics are getting rather tiresome :-/”
NOBODY has full operational knowledge of ANY particular field, otherwise there would be little dissent or disagreement fomented. Yet we have loud disagreement existing between Meteorologists, between Physicist, between Geologists and so on.
Recall Louis Agassiz, Darwin, Mendel, Milankovitch and more who as solitary researchers of a new science paradigm were often given disrespect and disagreeable replies.
Agassiz was a NATURALIST, Darwin was a Naturalist, Geologist and Biologist, Mendel was a scientist without a degree having repeatedly failed the Oral examination, was instead a Friar then an Abbot (Studying to be a Priest!) while he did his free lancing science research. Milankovitch was an ENGINEER
Snobbery doesn’t help your cause, it is efficacy of the argument irrespective of what learning or credentials they might have that can be the defining point in the debate.
It took about 50 years before Wegener basic geological point that continents have moved around, to be accepted by degreed geologists who up to that time were in general sneering Wegener’s lack of a Geology degree.
Heck even in the SAME science field there has been a tremendous controversy that lasted for decades as well between Geologist J. Harlan Bretz and the most of the rank and file Geologists who thought he was nuts.
Sigh.

Kristi Silber
February 6, 2018 5:09 pm

TONEB – Thank you very much for your contributions!
“No, it is interesting how some peeps think they know better than the experts, while having zero exptertise themselves.
Observed daily on here.”
YUP! I sure don’t know better than the experts, but I know enough to trust them more than I trust the kind of “science” that’s common around here.

Editor
February 6, 2018 11:14 pm

I see that Kristi, as well as JKrob thinks that only experts know what they are talking about.
“No, it is interesting how some peeps think they know better than the experts, while having zero exptertise themselves.Observed daily on here.”
“YUP! I sure don’t know better than the experts, but I know enough to trust them more than I trust the kind of “science” that’s common around here.”
You two have no idea how often “experts” have been wrong about their claims.

February 5, 2018 8:43 pm

This shows the same thing as a scatter plot of atmospheric water content as a function of the surface emissions considering the surface to be an ideal BB at its reported temperature.
I find that scatter plots are very useful at establishing the transfer functions between pairs of variables and they help translate correlation into understanding causation.

Alan Tomalty
February 5, 2018 10:23 pm

J = ê Õ T4 where ê is the emissivity black body coefficient Õ is the Stefan Boltzmann constant and T is the temperature to the 4th power and J = amount of IR in joules
Be careful when referring to black bodies. There is no such thing as ê =1 in a black body. The problem is noone knows what the value of ê is in the above equation that represents the earth surface as a black body. All analysis based on that equation is flawed until we find out what that value is for the earths surface if we ever do.

A C Osborn
February 6, 2018 6:05 am

Alan, the problem is there isn’t just one “grey body” value either, all they can do is talk in Averages, just like TSI.
In the day TSI starts at zero and increases to Max and then decreases back to zero and stays there all night long.

February 6, 2018 9:42 am

A non ideal black body IS a gray body and yes, there is no such thing as an ideal BB. However; it’s perfectly reasonable to consider the surface itself (i.e. below the atmosphere) to be close enough to an ideal BB to consider it so for the purpose of analysis. For example, the Moon’s surface is so close to an ideal BB that nothing else makes sense. The Earth’s surface is much the same while the atmosphere makes this emitting surface look more gray from space. Satellite inferred surface temperatures also assume an approximately ideal BB surface.
The sensitivity of an ideal BB is given EXACTLY by 1/(4 Õ T^3) and that of a non ideal BB is given EXACTLY by 1/(4 ê Õ T^3) where the emissivity, ê, has a value between 0 and 1 representing all deviations from ideal and T is the average temperature of the emitting surface being characterized, which in this case is the virtual surface whose temperature we care about and which is coincident with the top of the oceans and the top surface of the bits of land that poke through. The planet concurs and the relationship between the temperature of this surface (Y axis) and the planets emissions (X axis) corresponds so close to an ideal gray body that again, no other representation makes any sense whatsoever, even when short term (1 month) averages are considered which are represented by the cloud of red dots shown in this scatter diagram which represent the MEASURED averages for each 2.5 degree slice of latitude.
The resulting emissivity is unambiguously bound to be between 0.60 and 0.63 and when you calculate the sensitivity across these bounds as well as across the uncertainty in T (average surface temp), the AVERAGE sensitivity is consistently below the lower limit claimed by the IPCC. Part of the problem is that the IPCC refuses to acknowledge the 1/T^3 dependence of the sensitivity that is independent of the effective emissivity and instead, assumes approximate linearity as demonstrated by the blue line in the above scatter plot and extrapolates the higher sensitivity observed at cold temperatures as applying to the whole.
The only way to avoid the requirements of the Stefan Boltzmann LAW and its 1/T^3 dependence of the sensitivity is by applying magic which the IPCC relies on at every turn.

Robert of Texas
February 5, 2018 8:46 pm

Thinking through this post…So a thought experiment:
What would happen if you could artificially warm the oceans to 30C or 31C over the entire Earth. Forget living things – just a lifeless planet with water and land.
Would the entire ocean surface erupt into rain storms, or would there be giant rows of squall lines circling the planet (a kind of Jupiter look effect, but without all the cool colors)?
What happens if you keep warming? (artificially) Does the heat engine just ramp up or do you reach a point where it cannot cope anymore and the Earth warms faster and becomes Venus-like?
What happens to the energy from the sun? Does more and more become reflected energy directly back into outer-space, or could you actually reach a run-away warming? (Yeah, run away until it reaches some new equilibrium anyway).
Now turn the artificial heat off. Would not the entire Earth start cooling until once again, the oceans are under 30C? And at some point, wouldn’t some not-understood natural cycle cause the poles to freeze again and another ice age?
So the water evaporation effect helps contain the upper heat boundary, but what about the lower boundary? What is capping that boundary? Just the Sun? It must be. So if we are in an ice age, what brings us back out? It sure seems like it has to be the Sun again.
I like the idea that a variable Sun causes cycles, and evaporation controls (or helps to control) the upper limits. But it sure seems like there ought to be some geologic-chemistry evidence that the Sun is the control knob of ice ages if that’s true.

Alan Tomalty
February 5, 2018 10:35 pm

I like the sun idea and the sunspot idea too but not the sunspot cycles I cant believe that the suns fusion is anything but chaotic. Therefore how can you have a smooth cycle with chaos. I could accept the planet and sun wobble theory and maybe both are responsible for climate change. Perhaps even tectonic plate activity or earth molten core activity or changes in earths magnetic field, but I cant accept the AGW theory until someone shows me how it is supposed to work..

tty
February 6, 2018 12:52 am

“So if we are in an ice age, what brings us back out? It sure seems like it has to be the Sun again.”
It is. Read up on the Milankovich curve. However the last million years or so some other feedback clearly has kicked in since it now is only every second or third 41,000 year cycle that causes a full interglacial.

A C Osborn
February 6, 2018 6:10 am

The Sun is too simplistic on it’s own, although the biggest player by far, the amount of Water with added Geothermal heating is the other part of the equation.
It is H2O that stops the massive swings in Temperature that we see on the Moon and to a lesser extent in the Dry Deserts.

February 6, 2018 12:35 am

Look up a paper from 1970s by Newman and Dopplick. It was about how the tropics quench any possible CO2 forcing. A lot to do with evaporation and water vapour effects. They even had a phase diagram if I recall.

Steve Ta
February 6, 2018 1:32 am

I’m interested in the few samples that seem to follow the zero rainfall up to and above 30C. (fig 2). It does not appear to just be randomness below the line, since the samples tend to be either in the main population, or at 0, with very few in between.
As “the exception that proves the rule” could these samples provide additional information about why they manage to not follow the rule – perhaps due to wind patterns, or restricted area (Red Sea, perhaps) – and so explain more about why the blue line is exactly where it is?

richard verney
February 6, 2018 2:22 am

In practice, this means that at ocean temperatures up near 30°C, any extra incoming solar energy merely increases evaporation, with only a minimal increase in the sea surface temperature. This keeps the average sea surface temperature under 30°C everywhere in the open ocean.

i agree with the thrust of the first sentence, but as I have showed you (several years ago probably on one of your ARGO posts) there are large areas of oceans where temperatures are above 30degC, even above 32degC, and with some shallower seas (such as the Red Sea) getting up more towards 34degC. I consider the second sentence to be an over simplification, and perhaps, I would go as far as suggesting that it is even wrong.
I suspect that it is not the depth of these shallower seas that are important but rather the fact that they tend to be enclosed, at least at one side, such that currents (which distribute temperatures) are rather different, or perhaps it is due to differences in prevailing winds (given that winds increase the rate of evaporation).

Keith J
February 6, 2018 2:36 am

Don’t forget precipitation which never makes it to the surface. Virga is a powerful cooling effect.

Albert Brand
February 6, 2018 5:54 am

There is a very interesting paper by Robert Homes published in Earth Sciences in December and posted on Notrickszone yesterday. It basically states that the temperature of the earth can be calculated with no need of greenhouse gases. Therefore all these calculations everyone is doing is really only looking at how energy moves around on the earth and not the cause. I am only an engineer and will therefore refrain from making any comments on this matter.
Al

RWturner
February 6, 2018 7:53 am

30 degrees C must be the magic temperature where any additional energy instantly bypasses the atmosphere and surface waters and instead warms the deep ocean where it hides. /s

TG Mccoy
February 6, 2018 8:35 am

Wills-my greatest fear is a cat with opposable thumbs…
Had a Maine Coon that would’ve loved it..
but thumbs -no.

Samuel C Cogar
February 6, 2018 10:24 am

@ Willis Eschenbach
An interesting and informative commentary denoting the correlation between annual average rainfall and annual average sea-surface temperatures as denoted on your “Figure 2. Scatterplot” of the area of the equatorial Pacific that is bounded between 23.5°N latitude and 23.5°S latitude.
Now I am not a fan of, or a believer in the importance of, …… anything that has been calculated to have an “annual average, …… especially the often touted global or regional annual average near-surface air temperatures. Said “calculated averages”, IMHO, are only useful as reference data,
Anyway, my curiosity begs the question of, …… does the 18°C axis on your Figure 2 Scatterplot graph equate to a combined Solar position of the Sun being directly overhead at the Tropic of Cancer (northern solstice) and the Tropic of Capricorn (southern solstice), …….. whereas the 29°C axis on your Figure 2 Scatterplot graph equates to a Solar position of the Sun being directly overhead at the Equator (equinox)?

Gary Pearse
February 6, 2018 10:31 am

Great stuff as always. I believe you are writing future PhD theses for the Philistines. These graphs relate evaporative cooling to temperature. Is the cold rain that falls and, presumably cools the surface some more included in this relationship?

lgl
February 6, 2018 12:30 pm

I’m getting a very different result from the JRA-55 atlas.
http://virakkraft.com/Evap_SST_JRA-55.pdf

lgl
February 8, 2018 1:43 pm

No, it shows evaporation.

The Original Mike M
February 6, 2018 2:42 pm

It seems to me that, for lack of any other explanation, the strong negative feedback from increased evaporation, (including the resultant increase of albedo from more clouds that would have to have formed from it) likely explains why earth’s temperature seems to have had a hard limit of about ~23 degrees (globally so a few degrees higher in tropical waters or just above the knee in WIllis’ scatter plot) over the last 600 million years regardless of major CO2 fluctuation and even plate tectonics.
Disaster averted! Not only will earth not “burn up” if we keep warming, the area of rain forest is just going to keep growing in size (like it already has).

Tony
February 6, 2018 3:52 pm

From Flim Flam Flannery of the Climate Council: “Flannery Forecasts Perpetual Drought
Over the past 50 years southern Australia has lost about 20 per cent of its rainfall, and one cause is almost certainly global warming.”

Geoff Sherrington
February 6, 2018 7:43 pm

Hi Willis,
Your methods to display global measurements in bulk are tremendously valuable. They allow fast comprehension, they lead one on to further exploration of the theme. IMO, you should be generously funded to develop these even more, with the objective of creating a new national teaching source, among other aims.
Here are some suggestions along those lines. You have probably thought of them already, so pardon me if I wrongly come across as teaching about sucking eggs.
Several of your past graphs have made me go again and again to the Ted talk of Hans Rosling and other clips of his. (Sadly, Rosling died about a year ago.) https://www.ted.com/talks/hans_rosling_shows_the_best_stats_you_ve_ever_seen
The Rosling methods are excellent to display a third variable on a conventional XY axis graph. I would love to see your above Figure 1 Scatterplot of evaporative cooling versus sea surface temperature running on a time basis, be it year by year or season by season or whatever third variable is chosen.
The movements on some Rosling graphs remind me of the group flight patterns of birds. Videos at
http://www.dailymail.co.uk/news/article-2913471/Watch-flocks-birds-create-beautiful-patterns-sky-Netherlands.html
Some simple mathematics are at http://www.audubon.org/magazine/march-april-2009/how-flock-birds-can-fly-and-move-together
They note “It turns out that only three simple rules suffice to form tightly cohesive groups. Each animal needs to avoid colliding with its immediate neighbors, to be generally attracted to others of its kind, and to move in the same direction as the rest of the group. Plug those three characteristics into a computer model, and you can create “virtual swarms” of any sorts of creatures you like. They change density, alter their shape, and turn on a dime—just as real-world birds do”. I am still thinking if this has any practical outcome.
Coming back to the essence of your essay here, maybe you are close to answering a query from an earlier post about what regulated the feedback in the hypothesis of cloud-controlled thermostats for climate. I asked about the “set point” or reference value that is part of many feedback mechanisms. Now I am starting to feel that it might be tied to primarily the coefficient of thermal conductivity of sea water, regulating the rate at which ocean water heat can get to the surface to be evaporated until that temperature-limited behaviour is seen, as on your Figure 1. But as you note in a comment about outcomes of gravity changes, it is a very complicated matter. Geoff.

February 7, 2018 11:52 pm

@Willis Do you have any clue how to quantify the effect of “rain chill”? I am asking because it is vital point in determining net cloud forcing. Rain falls from clouds in will lower temperatures in correlation with cloudiness, but that is not due to CF of course.
To illustrate the issue, these are data from tropical (US) stations – temperature vs. low cloud condition (up to 12.000ft)
http://i736.photobucket.com/albums/xx10/Oliver25/cloudsvstemp%20tropical.png
And here is the amount of rain according to (low) cloud condition..
http://i736.photobucket.com/albums/xx10/Oliver25/rangliste%20prec.png
If you wonder why there is rain from clear skies, again these are only clear up to 12.000ft..
Anyhow, to perfection the subject (which obviously shows a net positive cloud forcing!!!), it would be great to quantify that rain chill factor.

February 8, 2018 4:20 pm

Right, there are a lot of factors, but the most basic idea I had in mind is rain itself. As it originates in higher altitudes where it is much colder than at the surface, the rain itself will be cold. Rain (or snow) will warm up, as it falls through the warmer, lower atmosphere, but still its temperature will lag far behind. Especially when it is generally warm, one can fairly well see how a little shower quickly drops temperatures.
Overall there are a couple of factors which are affiliated with cloudiness, which will lower temperatures, but are not cloud forcing. So it would be great to single them out, but as I told, I see no way to fairly quantify them.
All I know is, that their impact will be overproportionately strong with OVC skies, which then would look much warmer if we could sort it out. In fact we might have a very straight linear trend, with temperatures being the warmer, the more clouds there are. Which is amazingly funny of course, as we are talking about low clouds in the tropics. That should be the clouds with the biggest negative CF of all.