Guest Post by Willis Eschenbach
I got to thinking again about the thunderstorms, and how much heat they remove from the surface by means of evaporation. We have good data on this from the Tropical Rainfall Measuring Mission (TRMM) satellites. Here is the distribution and strength of rainfall, and thus evaporation, around the middle of the planet.
Figure 1. Evaporation in W/m2 as shown by rainfall data from the TRMM. It takes about 80 watt-years of energy to evaporate a cubic metre of water, so a metre of rainfall per year is equivalent to an average surface cooling of 80 watts per square metre. The TRMM satellite only covers from 40° North to 40° South.
I have held for some time that the global surface temperature is restricted to a fairly narrow region (e.g. ± 0.3°C over the 20th century) by the action of emergent phenomena (see references at the end of the post). Chief among these emergent phenomena are tropical thunderstorms. My hypothesis says that when the tropical surface temperature goes over a certain threshold, that thunderstorms emerge to put a firm cap on the temperature by cooling the surface.
Thunderstorms cool the surface in a number of ways, but the main cooling method uses the exact same mechanism used by the refrigerators that keep our food cold. Thunderstorms use a standard evaporation/condensation cycle. In one part of the cycle the working fluid evaporates, cooling the surroundings. In another part of the cycle in another location, the working fluid condenses. For a refrigerator, the working fluid used to be some form of Freon, nowadays it’s some other fluid. For thunderstorms, the working fluid is water. When it evaporates at the surface, it cools the local area, and the heat is moved from the surface to the clouds and on upwards.
Now, for my hypothesis to be correct, the number and intensity of thunderstorms needs to increase quickly as temperatures go above a certain temperature threshold. In addition, the change in the resulting evaporation needs to be quite large in order to successfully control the system.
With that in mind, I made a scatterplot of sea surface temperature versus thunderstorm evaporative cooling. Figure 2 shows that result.
Figure 2. Scatterplot of 1° x 1° gridcell annual average ocean-only thunderstorm evaporative cooling on the vertical axis, in watts per square metre (W/m2) versus 1° x 1° gridcell annual average sea surface temperature on the horizontal axis.
As you can see, the thunderstorms are clearly functioning to cap the temperature. When the ocean surface gets hot, thunderstorms form and exert immense cooling power. There are some points worth noting about Figure 2.
First, the red area shows the tropics. This part of the earth is important because it is not only about 40% of the planet’s surface. In addition, just over half of all the energy absorbed by the surface of the earth is absorbed in the tropical regions of the planet. As a result, the regulation of this large amount of incoming energy by albedo control is crucial to the overall energy balance of the planet.
Next, these are annual averages. However, they are also daily averages. But during the day/night cycle in the tropics, the evaporation is by no means constant. At night the evaporation is small, some tens of watts per square metre. During the day, on the other hand, evaporation is quite large, hundreds of watts per square metre, because the strong tropical sunshine evaporates the water directly, plus the thunderstorms are largely a daytime phenomenon. This means that the peak hourly thunderstorm evaporative cooling is on the order of twice the average values shown above, up to about 600 W/m2.
Next, the cooling effect of the thunderstorms is not applied blindly or randomly. The thunderstorms only form as and when the local area is above the temperature threshold. This means that the cooling effect, which can be up to 500-600 w/m2, is always located where it is most needed, on the local hotspots.
Finally, here is the most important consideration. The timing and the amount of thunderstorms are NOT a function of greenhouse gas forcing, or of solar forcing, or of volcanic forcing, or of any other kind of forcing. As Figure 2 shows, they are a function of temperature. As long as the surface-atmosphere temperature difference is large enough, thunderstorms will form even at night when the radiative forcing is quite small.
This means that their effect will be to maintain the same temperature, regardless of reasonable-sized fluctuations in the amount of forcing. Clouds don’t know about forcing, they form and disappear based on local conditions.
And this is simply one more piece of observational support for my hypothesis that emergent phenomena regulate the temperature and maintain it within a fairly narrow range.
My best to everyone. Here in California, we have about 150% of the usual snowpack in the Sierra Nevada mountains. When it was drought, it was said to be the result of global warming … and of course, now that there is heavy snow, that is also said to be the result of global warming.
Buckle your seatbelts and keep your hands inside the vehicle, it’s gonna be a long, uphill struggle to get rid of this madness …
My best to all,
w.
My Usual Request: If you disagree with me or anyone, please quote the exact words you disagree with. I can defend my own words. I cannot defend someone’s interpretation of my words.
My Other Request: If you think that e.g. I’m using the wrong method on the wrong dataset, please educate me and others by demonstrating the proper use of the right method on the right dataset. Simply claiming I’m wrong doesn’t advance the discussion.
Some Of My Previous Posts On The Subject:
Cooling and Warming, Clouds and Thunderstorms
Data:
TRMM Data is here, see the bottom of the page for the NetCDF file.
CERES Data is here, I used the EBAF dataset.
Willis a nice article.
You may be interested in this NOAA FAQ site. This part looks at energy released by hurricanes per day. A hurricane is after all a bunch of thunderstorms working together and hurricanes only occur when the SSTs are sufficiently high (85F or more) so they fit very well with your hypothesis.
This FAQ states interalia:
“It turns out that the vast majority of the heat released in the condensation process is used to cause rising motions in the thunderstorms and only a small portion drives the storm’s horizontal winds.
Method 1) – Total energy released through cloud/rain formation:
An average hurricane produces 1.5 cm/day (0.6 inches/day) of rain inside a circle of radius 665 km (360 n.mi) (Gray 1981). (More rain falls in the inner portion of hurricane around the eyewall, less in the outer rainbands.) Converting this to a volume of rain gives 2.1 x 1016 cm3/day. A cubic cm of rain weighs 1 gm. Using the latent heat of condensation, this amount of rain produced gives
5.2 x 1019 Joules/day or
6.0 x 1014 Watts.
This is equivalent to 200 times the world-wide electrical generating capacity – an incredible amount of energy produced!”
http://www.aoml.noaa.gov/hrd/tcfaq/D7.html
Note: that is 200 times the world wide electrical generating capacity per hurricane day
I often am amazed by the hubris of humanity thinking that they are all powerful. We are dwarfed by nature. Ants and Termites produce far more CO2 than humans. Not that CO2 matters.
But what about all that most powerful of GHGs, water vapor, being released into the atmosphere at low altitudes via evaporation following the storm?
Rate of evaporation is not only a function of fluid temperature, but it is also proportional to surface area of the interface. As long as there is no storm, this area is pretty small (it is the sea surface). However, once a storm is started, high winds produce a prodigious amount of sea spray, which increases interface area by several orders of magnitude, so the entire thing becomes a self propelling engine. Until sea surface cools down sufficiently, of course. Anyway, there is this hysteresis, which should also be taken into account.
Willis-
Another of your excellent postings. Continuing thanks.
There is one thing not touched on here, which I have never seen anywhere else either. That is the amount of energy moved upward worldwide compared with the same for radiation. Do you have such a comparison?
Ian M
Willis,
Here’s something else to ponder. Take a surface of sea, say a square foot by an inch deep. The surface area of that water is 1 ft^2. Now evaporate it and condense it at 50,000 ft. What is the surface area of the water now? It is several orders of magnitude higher. Therefore you have much more surface area to radiate heat to outer space. This is the piece that the climate alarmists don’t understand.
The graph reminds me of a fat hockey stick. 🙂
I worked outside for like 20 years in the Chicago area, and as a bit of a weather geek, I noticed that if the cumulus started getting puffy by say 10 or 11 in the morning, there was a good chance of thunderstorms later in the day.
“plus the thunderstorms are largely a daytime phenomenon. ”
Not necessarily.
“Over the tropical and southern oceans, showery precipitation tends to peak from midnight to 0400 LST. Maritime thunderstorms occur most frequently around midnight.”
From http://www.rengy.org/uploadfile/file/中文版/资源/文献/2000/Global%20precipitation%20and%20thunderstorm%20frequencies%20Part%20II%20diurnal%20variations%20.pdf
Title (if link doesn’t work): Global Precipitation and Thunderstorm Frequencies. Part II: Diurnal Variations
An opportune time for a reprise, an encore post.
First off a discussion of units.
A watt is a metric unit of power, energy over time, not energy per se. The metric energy unit is the joule, English energy unit is the Btu. A watt is 3.412 Btu per English hour or 3.600 kilojoule per metric hour.
In 24 hours (sun shining, what happens at night?) ToA power of 340 W/m^2 will deliver 1.43 E19 Btu to a spherical surface with a radius of 6,386 km. The CO2 RF of 2 W/m^2 will deliver 8.39 E16 Btu, 0.59% of the ToA.
At 950 Btu/lb of energy, evaporating 0.74 inches of the ocean’s surface would absorb the entire ToA, evaporating 0.0044 inches of the ocean’s surface would absorb the evil unbalancing CO2 RF.
More clouds. Big deal.
ToA spherical surface area, m^2……………5.125.E+14
W = 3.412 Btu/h……………………………………3.412.E+00
ToA, 340 W/m^2, Btu/24 h……………………1.43E+19
CO2 RF, 2 W/m^2, Btu/24 h…………………..8.39E+16
Ocean surface , m^2………………………………3.619E+14
m^2 = 10.764 ft^2………………………………….1.076E+01
Ocean surface, ft^2………………………………..3.895E+15
Water density, lb/ft^3………………………….62.4
Lb of water in 1 foot of ocean………………..2.431E+17
Evaporation, Btu/lb……………………………950.0
Amount of ocean evaporation
Feet needed to absorb ToA…………………..0.062
Inches needed to absorb ToA………………..0.74
Feet needed to absorb CO2 RF………………0.0004
Inches needed to absorb CO2 RF…………..0.0044
Don’t like my work? Think it’s wrong or irrelevant? At least I took a shot at doing it. Where’s your work?
Fun-duh-mentals.
Willis,
I’m glad someone finally started talking about the verticle transport of latent heat.
The point that everybody is missing is that the AGW models don’t factor this in. They only look at convection of sensible heat. This is a fatal error.
Also, ponder this: According to AGW enthusiasts, if there is more CO2 in the lower troposphere then more infrared radiation is reflected back to the surface. That means more evaporation. More important, it means less infrared being absorbed by water vapor above and therefore a cooler upper troposphere. That means more clouds. More clouds means higher albedo and less sunlight reaching the surface. That means cooling. Therefore CO2 causes global cooling.
If that isn’t enough, the increased CO2 below actually creates a reverse greenhouse effect by reflecting the infrared radiation coming down from above back out towards space. Oops. Nobody thought about the fact that the “greenhouse effect” is a two edged sword.
CARBON DIOXIDE CAUSES GLOBAL COOLING!
I sent Anthony a paper on this a few days ago. Ask him about it. Somebody needs to take the ball and run with it.
IPCC AR5 gave clouds a -20 W/m^2 RF.
Willis
Are you going to update your cloud thermostat paper, to include all of these developments?
http://www.friendsofscience.org/assets/documents/E&E_Thunderstorm_Hypothesis_Eschenbach.pdf
R
OK, the twit is erased, we can rid of that now !!
From Held: http://www.gfdl.noaa.gov/blog/isaac-held/2015/09/09/62-poleward-atmospheric-energy-transport/#more-9254
A warming atmosphere typically results in larger horizontal moisture transports. In addition to the implications for the hydrological cycle and oceanic salinity discussed in previous posts, this increased moisture transport also has implications for energy transport. If energy is used to evaporate water at point A and the vapor is transported to point B where it condenses, releasing the heat of condensation, energy has been transported from A to B. This latent heat transport is a large component of the total atmospheric energy transport. Outside of the tropics, eddies are mixing water vapor downgradient, resulting in a poleward transport. Close to the equator, the Hadley circulation dominates, with its equatorward flow near the surface that carries water vapor from the subtropics to the tropical rain belts (the compensating poleward flow near the tropopause carries very little water vapor in comparison).
Held speaks about the ratio between horisontal an vertical energy trensport. The vertial is very little compared to the horisontal. As I understand some of the comments thunderstorms modify this by increasing heat upwards. And that this can go to latitudes that give more radiation to space. I think it is very ineresting to see the “thermostat” as a result of both vertical and horisontal motion of air and moisture.
Willis
I have a couple of questions for you arising out of various statements quoted below:
We live on a water world, and understanding the water cycle is the key to understanding the planet’s climate, but I do not understand the above assumption. As I have previously mentioned to you, energy absorbed in one part of the system re-emerges in a different part of the system because of oceanic and atmospheric currents, and of course, not all energy is absorbed at the surface, and some of the energy absorbed say in the 20cm to 5 m depth of the ocean is mixed vertically downwards.
Fisrt, If you look at Fig1 (and if I understand matters correctly), are you really saying that there is no evaporation in the dark blue areas, say off the East Coast of Africa, or off the West Coast of Australia? The Figure portrays that much of the Indian Ocean (vast areas of which are particularly warm) has no evaporation!
You also state:
I do not know how that approximation/rule of thumb has been calculated, but (if my maths is correct), given that the specific heat of water (which is 4.186 Joule/gram °C), that means that it requires some 293.02 Joules of energy to heat 1 gram of water by 70 °C (ie., from about 30 °C to 100 °C).
Now then due to the omnidirectional nature of DWLWIR approximately some 60 to 70% of all DWLWIR is fully absorbed in just 3 microns of the ocean. This is a volume of just 0.000003 cubic metres and is a mass of some 3 grams. According to K & T, the global average DWLWIR is some 324 W/m^2, and ignoring the fact that in the tropical region DWLWIR will be considerably higher than the global average, there is approximately some 226 W/m^2 (ie., 324 x 70%) or 226 Joule Seconds being fully absorbed in just 3 microns. Thus, it would take just 1 second to entirely evaporate the 3 micron layer (in which about 60 to 70% of all DWLWIR is fully absorbed), and this means that if DWLWIR possesses sensible energy and is capable of performing sensible work in the environ in which it finds itself, the oceans would boil off from the top down, and would no longer remain given that they have received this energy for the best part of some 4.5 billion years, unless the energy that is absorbed in the top 3 microns can be sequestered to depth and hence diluted and dissipated by volume at sufficient speed to prevent this energy from boiling off the top microns of the oceans. This leads on to my next question.
Second, the question is what physical processes operate to mix this energy and sequester it to depth at sufficient rate to prevent this boil off?
In the past, you have mentioned processes such as ocean overturning, the action of the wind, waves and swell. My response to that is that these are all slow mechanical processes, and do not operate 24/7 365 days of the year.
For example, ocean overturning is a diurnal event, and therefore can at best only operate for half the day. Further, there may be no equivalence in some large inland seas, lakes such as the Great lakes, the Dead Sea, the Sea of Azov etc.
The action of wind, waves and swell cannot operate effectively when weather conditions are in the order of BF2 when there is simply insufficient wind to break surface tension, and to cause waves etc to carry out any mixing.
When we last discussed this (before Christmas), I mentioned that I was overlooking the Mediterranean and it was as still as a millpond with not a ripple in sight. The local weather station suggested that the prevailing wind speed was 1 mph, so one can see why there was no mixing by this slow physical process. I asked you why the Med was not boiling off from the top down. Again, today, similar conditions are being encountered although it is said to be a little windier at 5 mph. This is midway in BF2, ie., a light breeze and according to the BF scale, there should be “small wavelets, crests of glassy appearance, not breaking”. Where I am the trees are not rustling at all, and one cannot feel any breeze on the skin even if licked, and I would estimate that the local conditions are more like BF1 (I have 40 years plus of sailing experience), so I would again enquire why is the Med not boiling off from the top down as we correspond?
All I want to know is what physical process can on a 356 24/7 basis sequester the DWLWIR being absorbed in the top few microns of the oceans down to depth (and hence dilute and dissipate that energy by volume) with sufficient rate so as to prevent that energy from simply boiling off the top microns?
I do hope this time to receive an answer to the questions posed.
Richard Verney “…DWLWIR…”
IMHO (BSME, PE, 35+ years in power gen) whether conduction, convection or radiation heat flows from hot to cold, not from a colder LT to a warmer surface. S-B would be negative in this delta T direction. This popular upwelling/downwelling GHG radiation loop is a basic perpetual motion violation of thermodynamic principles.
Plus because of Einstein’s Nobel winning photo electric effect any re-emitted energy has to be less than the incident energy, difference being the work function and in the microwave range.
Which is all academic because:
1) Mankind’s net 4 GT/y CO2 contribution to the globe’s 45,000 GT of stores and 100’s of Gt/y natural fluxes is trivial.
2) CO2’s 2 W/m^2 RF is trivial.
3) The GCMs are trash.
Willis,
Reading richard verney’s comments got me to thinking along a bit of a tangent to this topic, but I’d love to hear your thoughts on it anyway:
I wonder what the net effect of continental run-off is on ocean temperatures? It seems like water running off the land would tend to be more easily warmed prior to entering the sea, thus providing a net source of warming to the oceans. This would vary, of course, as regional/planetary climate cycles alternate between warm and cold, seasonally & by epoch. But I wonder if part of the reason the ocean warms at all in large scale is due to a warming of continental run-off compared on average? The “run-off anomaly,” if you will?
Just thinking of the possible plus sign(s) which might run counter to the minus sign you got going with the ITCZ. Thanks for your work!
I found an atmospheric heat/power flux balance diagram among Bing images that is labeled “Fig 10 Trenberth et. al. 2011.” Some of you might recognize the paper. What is interesting is that there are eight values and an average displayed for each of the major state points. From what I can tell there are eight different studies/data bases/calcs and in some cases with quite different values. What happened to consensus? A couple of the variation ranges/uncertainties are an order of magnitude greater than anthropogenic CO2’s 2 W/m^2 RF. And there is the 333 W/m^2 perpetual (GHG?) power flux loop between earth’s surface and sky, i.e. lower troposphere.
A summary table:
………………………..ave W/m^2…..+/- %…+/- W/m^2
ToA net…………………342.1……….1.5……..…..5.13
OLR…………………….243.9………..9.0……..…21.95
Albedo, %…………………29.8……..…..3.5……..…..1.04
Surface Radiation……..398.0……….2.5…….……9.95
Back Radiation……..….338.3……….8.5…………28.76
Evapo transpiration…….85.1…….….9.0……….…7.66
Reflected Surface………27.4…………5.7…………1.56
Reflected Solar………..101.4…….….11.5….…….11.66
Latent Heat…….……….88.1………….8.0…..….…7.05
Per IPCC AR5 the cumulative CO2 RF between 1750 and 2011 is 2 W/m^2. OLR uncertainty is +/- 22 !!!!!!! Reflected solar +/- 12!!! Even RCP 8.5 gets lost in uncertainties this large. How can anybody claim significant confidence in the present or future global temperatures with such huge uncertainties?
Thanks, Willis, for a very good article.
Yes, I can see thunderstorms moving heat up to be radiated out, and how this conforms a feed-back control of local weather in the tropical and sub-tropical regions.
Your “scatterplot of sea surface temperature versus thunderstorm evaporative cooling” (Figure 2) is very convincing evidence.
Happy New Year!
Willis, if the thunderstorms are shifting heat upwards:
“For thunderstorms, the working fluid is water. When it evaporates at the surface, it cools the local area, and the heat is moved from the surface to the clouds and on upwards.”
Shouldn’t this show up in the satellite data as warming in the upper troposphere like the global warming fingerprint that hasn’t been found?
This I believe is the big flaw in the climate models which use a constant lapse rate to view water vapor and ignore heat transfer by thunderstorms. The model grid cells are much too large for thunderstorms anyway. If thunderstorms were not dissipating heat, they would not exist. They transfer massive amounts of heat to the upper atmosphere where it is more easily lost to space. It is like boiling a pot of water. As long as bubbles can form and rise, the water stays at the boiling point. Only in a pressure cooker can the water get hotter than this.
I think this is also why the ice ages were very dry–not much ocean warm enough to create convective storms.
In the HVAC industry a common term for cooling is the ton. It’s the amount of energy stored in a short ton, 2,000 lb of ice, 12,000 Btu or 3,517 Wh. That’s the energy needed to freeze a ton of water into ice or the energy released from melting that ton of ice and cooling the air circulating in the building.
Antarctica covers 14 E6 km^2 (14 E12 m^2) more or less. Snow and ice a meter deep would be 14 E12 m^3. A m^3 holds a tonne of water (slightly more ice), 2,204 lb, and would represent 13,224 Btu.
Precipitate a meter deep by square meter (i.e. cubic meter) of snow/ice over 24 hours, 13,224/24 h = 551.3 Btu/h or 161.6 W/m^2. That cubic meter of snow/ice precipitated over Antarctica would remove 5.43 E16 W from the atmosphere. Wow! Good thing it doesn’t snow much in Antarctica.
In 24 hours ToA of 340 W/m^2 delivers 17.4E16 W.
So it would take almost undetectable amounts of snow/ice at the ice caps and sheets to suck up mankind’s pitiful 2 W/m^2 of CO2 RF.
Subject to peer R&C.
It’s time to acknowledge that the atmosphere is a three-phase system.
Willis, along with some of the commentators, has opened the door on something that goes way beyond thunderstorms. Where this must ultimately lead is the realization that all current models are 100% useless – because they don’t properly consider the transport of latent heat as water transitions through gas, liquiid and solid phases.
A thunderstorm is the biggest example of latent heat transport but every cloud is doing the same thing to some degree. You have to look at the entire hydrological cycle. Every bit of evaporation at the surface moves up in the atmosphere and eventually returns to the surface. It must – otherwise the atmosphere would load up with water.
Latent heat is captured at the point of melting/evaporation/sublimation and released at the point of freezing/condensation/desublimation. Most of it is captured at the surface and released somewhere in a cloud, but that’s not the only way.
There is also a massive amount of capture happening up in the atmosphere. Virga (raindrops that evaporate before they hit the ground) are just one example. All clouds are really continuous heat pumps that are capturing latent heat below and releasing it above. You can see this if you watch fast-motion video of cumulus clouds. The roiling of the cloud is caused by droplets falling from the top and re-evaporating somewhere down below.
Furthermore, a lot of evaporation & condensation is happening invisibly at the microscopic level. Just because you don’t see a cloud doesn’t mean it isn’t happening. When you look up and see sky that isn’t cloud but isn’t as blue as it should be, or when you see haze, you’re getting a peek at this phenomenon.
So, the entire atmosphere is a continuous, dynamic phase-transition process. That’s important because latent heat released up in the atmosphere will presumably escape to space more readily – and because latent heat is a significant portion of the heat in the atmosphere.
Good luck modeling that. Heck, good luck even measuring that.
Now here’s the real mind blower: Once you acknowledge a three-phase system you have to start distinguishing between temperature and enthalpy. Delta T does not equal delta H so you can’t just stick a thermometer out the window any more. Poof (that’s the sound of the entire climate paradigm going up in smoke).
I’m glad I’m not a climatologist. You’ve got your work cut out for you. I’m out of here.
“Delta T does not equal delta H”
For liquid water it’s close enough, beyond that, good luck! e.g. 50/50 glycol & vapor, et.al.
Thanks Willis Good job
“At night the evaporation is small, some tens of watts per square metre. During the day, on the other hand, evaporation is quite large, hundreds of watts per square metre, because the strong tropical sunshine evaporates the water directly, plus the thunderstorms are largely a daytime phenomenon.”
To really nail down evaporation, one needs to keep record of wind speeds.