Guest Post by Willis Eschenbach
I took another ramble through the Tropical Rainfall Measurement Mission (TRMM) satellite-measured rainfall data. Figure 1 shows a Pacific-centered and an Atlantic-centered view of the average rainfall from the end of 1997 to the start of 2015 as measured by the TRMM satellite.
There’s lots of interesting stuff in those two graphs. I was surprised by how much of the planet in general, and the ocean in particular, are bright red, meaning they get less than half a meter (20″) of rain per year.
I was also intrigued by how narrowly the rainfall is concentrated at the average Inter-Tropical Convergence Zone (ITCZ). The ITCZ is where the two great global hemispheres of the atmospheric circulation meet near the Equator. In the Pacific and Atlantic on average the ITCZ is just above the Equator and in the Indian Ocean, it’s just below the Equator. However, that’s just on average. Sometimes in the Pacific, the ITCZ is below the Equator. You can see kind of a mirror image as a light orange horizontal area just below the Equator.
Here’s an idealized view of the global circulation. On the left-hand edge of the globe, I’ve drawn a cross section through the atmosphere, showing the circulation of the great atmospheric cells.
The ITCZ is shown in cross-section at the left edge of the globe in Figure 2. You can see the general tropical circulation. Surface air in both hemispheres moves towards the Equator. It is warmed there and rises. This thermal circulation is greatly sped up by air driven vertically at high rates of speed through the tall thunderstorm towers. These thunderstorms form all along the ITCZ. These thunderstorms provide much of the mechanical energy that drives the atmospheric circulation of the Hadley cells.
With all of that as prologue, here’s what I looked at. I got to thinking, was there a trend in the rainfall? Is it getting wetter or drier? So I looked at that using the TRMM data. Figure 3 shows the annual change in rainfall, in millimeters per year, on a 1° latitude by 1° longitude basis.
I note that the increase in rain is greater on the ocean vs land, is greatest at the ITCZ, and is generally greater in the tropics.
Why is this overall trend in rainfall of interest? It gives us a way to calculate how much this cools the surface. Remember the old saying, what comes down must go up … or perhaps it’s the other way around, same thing. If it rains an extra millimeter of water, somewhere it must have evaporated an extra millimeter of water.
And in the same way that our bodies are cooled by evaporation, the surface of the planet is also cooled by evaporation.
Now, we note above that on average, the increase is 1.33 millimeters of water per year. Metric is nice because volume and size are related. Here’s a great example.
One millimeter of rain falling on one square meter of the surface is one liter of water which is one kilo of water. Nice, huh?
So the extra 1.33 millimeters of rain per year is equal to 1.33 extra liters of water evaporated per square meter of surface area.
Next, how much energy does it take to evaporate that extra 1.33 liters of water per square meter so it can come down as rain? The calculations are in the endnotes. It turns out that this 1.33 extra liters per year represents an additional cooling of a tenth of a watt per square meter (0.10 W/m2).
And how does this compare to the warming from increased longwave radiation due to the additional CO2? Well, again, the calculations are in the endnotes. The answer is, per the IPCC calculations, CO2 alone over the period gave a yearly increase in downwelling radiation of ~ 0.03 W/m2. Generally, they double that number to allow for other greenhouse gases (GHGs), so for purposes of discussion, we’ll call it 0.06 W/m2 per year.
So over the period of this record, we have increased evaporative cooling of 0.10 W/m2 per year, and we have increased radiative warming from GHGs of 0.06 W/m2 per year.
Which means that over that period and that area at least, the calculated increase in warming radiation from GHGs was more than counterbalanced by the observed increase in surface cooling from increased evaporation.
Regards to all,
w.
As usual: please quote the exact words you are discussing so we can all understand exactly what and who you are replying to.
Additional Cooling
Finally, note that this calculation is only evaporative cooling. There are other cooling mechanisms at work that are related to rainstorms. These include:
• Increased cloud albedo reflecting hundreds of watts/square meter of sunshine back to space
• Moving surface air to the upper troposphere where it is above most GHGs and freer to cool to space.
• Increased ocean surface albedo from whitecaps, foam, and spume.
• Cold rain falling from a layer of the troposphere that is much cooler than the surface.
• Rain re-evaporating as it falls to cool the atmosphere
• Cold wind entrained by the rain blowing outwards at surface level to cool surrounding areas
• Dry descending air between rain cells and thunderstorms allowing increased longwave radiation to space.
Between all of these, they form a very strong temperature regulating mechanism that prevents overheating of the planet.
Calculation of energy required to evaporate 1.33 liters of water.
#latent heat evaporation joules/kg @ salinity 35 psu, temperature 24°C
> latevap = gsw_latentheat_evap_t( 35, 24 ) ; latevap
[1] 2441369
# joules/yr/m2 required to evaporate 1.33 liters/yr/m2
> evapj = latevap * 1.33 ; evapj
[1] 3247021
# convert joules/yr/m2 to W/m2
> evapwm2 = evapj / secsperyear ; evapwm2
[1] 0.1028941
Note: the exact answer varies dependent on seawater temperature, salinity, and density. These only make a difference of a couple percent (say 0.1043 vs 0.1028941). I’ve used average values.
Calculation of downwelling radiation change from CO2 increase.
#starting CO2 ppmv Dec 1997
> thestart = as.double( coshort[1] ) ; thestart
[1] 364.38
#ending CO2 ppmv Mar 2015
> theend = as.double( last( coshort )) ; theend
[1] 401.54
# longwave increase, W/m2 per year over 17 years 4 months
> 3.7 * log( theend / thestart, 2)/17.33
[1] 0.0299117
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Thanks, Willis. Heat engines rule. And govern (as in governor mechanism.)
For those who commented above with the sense that precipitation heating only moves heat from one place to another, consider that NASA as an institution knows perfectly well how heat engines work and how this concept applies. Here are two quotes from a NASA Earthobservatory website article “Climate and Earth’s Energy Budget” from January 14, 2009, authored by Rebecca Lindsey (this article can still be found by searching):
“The climate’s heat engine must not only redistribute solar heat from the equator toward the poles, but also from the Earth’s surface and lower atmosphere back to space. Otherwise, Earth would endlessly heat up.
Earth’s temperature doesn’t infinitely rise because the surface and the atmosphere are simultaneously radiating heat to space.”
And “At an altitude of roughly 5-6 kilometers, the concentration of greenhouse gases in the overlying atmosphere is so small that heat can radiate freely to space.”
So the greenhouse effect diminishes with altitude, and the heat engine delivers it there, as high as necessary, to supply the variable emitter. The precipitation rate indicates the performance of the heat engine.
I’m replying to my own comment here to add a screenshot of the WSI Radar Summary image, which is freely available on the web. This is from a short while ago. Altitudes are given in three-digit flight levels, e.g. 500 = 50,000 feet, which is about 15 km. Springtime in the U.S. brings convective weather, illustrating the powerful localized heat-engine nature of the atmosphere’s response to temperature and water vapor at and near the surface. This response is promoted by the strong greenhouse effect at low altitudes. The radar returns include some orange, which corresponds to a rain intensity of about 1 inch per hour, which implies upward heat delivery of 16,000 W/m^2. My point: Willis gets it exactly right to emphasize how precipitation should be understood. Cooling by evaporation at and near the surface, heating by condensation and freezing at high altitudes where heat can more easily escape to space. Watch it happen yourself, and lose the fear of greenhouse gases.
?dl=0
Picked this up from a commentator on JoNova blog. Graphs of temperatures around the world, quick summary the sky is not falling.
https://chiefio.wordpress.com/2019/04/28/ghcn-v3-3-vs-v4-anomaly-australia-pacific-islands/
It is revealing to compare the 2 Watts/sq.M. (from 280 pre-industrial to 400 ppm today) that the CO2 radiative forcing equation yields, to what is shown from an image search on “Uncertainty in Global Energy Balance”…
Good stuff, Willis. I wish ‘official’ climate scientists produced straightforward illustrations of phenomena from the superb data that is actually available without sticking their fingers and homemade statistics into the process.
Question. Is the 1/3 missing from the balance simply supplied by the effect of the land masses?
Willis, surface cooling from increased evaporation is balanced equally by atmospheric condensation. The net is zero. Moving heat from point A on the surface to point B in the atmosphere does nothing to cool the planet. The ONLY way for heat to escape our planet is via radiation.
Lionheart, the heat is removed from the surface and released up high in the atmosphere. Per NASA, from a comment above:
So moving the heat from the surface to the upper troposphere assuredly cools the planet.
w.
It can only be ‘released’ after it condenses which means it can only be released by clouds. But, when emissions from cloud tops reaching space are measured by weather satellites, they are consistently less than emissions by the same surface under clear skies. It seems that the net result of water vaoir is to reduce the emissions by the planet.
Obviously. Cloud tops are far cooler than the surface underneath. You would have a much different Planck spectrum. The other difference is that cloud radiation is diffuse.
The design of a spectrophotometer is such that it ‘looks at’ a narrow cone. It just doesn’t see as much light from a diffuse surface. To correct for this you need an algorithm of some kind. Clouds have different densities of droplets and sizes so you would need a variable algorithm depending on the situation. Results could be way out at times. Not my job or headache to fix it.
Alex,
Once you get a few meters above the cloud tops, cloud emissions are no more diffuse than surface emissions a few meters above it, whose emitted photons also leave in all directions. Cloud emissions originate from different depths, but from above the cloud, the depth where a photon was emitted is irrelevant.
Satellite sensors are tuned to the transparent parts of the spectrum, so it’s relatively easy to infer the relative emitted surface or cloud power by the relative strength of emissions in the transparent bands and convert to a temperature using SB. Of course, you need to make adjustments for varying water vapor and ozone concentrations which are not as well mixed as CO2.
A significant difference is that there’s little or no water vapor between cloud tops and space, thus the GHG effect from water vapor has little effect on cloud emissions into space.
A complication is that clouds are not completely opaque to surface emissions and if we consider that the average cloud coverage is about 66% which includes partly cloudy skies and thin clouds, on average about 20% of the surface emissions will pass through the cloud layer without being intercepted by cloud water and whose radiant emissions must be accounted for in order to establish actual cloud top temperatures. This is a more complex calculation and requires knowing more about specific cloud properties.
The wavelength where the Plank emissions are maximum is proportional to 1/T, where the average surface T is about 288K and the average cloud T is about 260K, so the peak average wavelengths of the resulting emissions varies by only about 1.5 microns.
I disagree with your definition of diffuse radiation. I am separating diffuse from lambertian. The ‘diffuse’ I am talking about is like the blue sky. Also the appearance of things through frosted glass. These are both not limited to a few meters. Clouds act in the same way. I remember some years ago, noting on an overcast day, that there were no shadows on any of the walls of a quadrangle 4 stories high and about 100 metres per side. I was there from early morning till late in the afternoon. There is no reason to think that the bottom of clouds would act differently to the top. It’s worthwhile googling ‘why are clouds white’. Specular reflection of visible light and IR are the same but transmittance will be different.
SB applies to a blackbody only. Throwing in a factor for emissivity is a joke. The emissivity of a non-gray body varies from wavelength to wavelength. the result is that the temperature/ energy function is non linear. Some people like to use albedo for reflectance, which shows a straight horizontal line between 0.3 and 3 microns. Nothing could be further from the truth. As far as I’m concerned, these people are either ignorant( lack of knowledge) or just plain lazy. Information on reflectance is available free online and the calculation for emission is straightforward on a spreadsheet program. Maybe the results doing things the easy way are similar. I just prefer to use better methodology.
Alex,
You’re referring to a shadow from visible light and not an LWIR shadow, the difference being that visible light is sunlight filtered and diffused by clouds, while the water in clouds is the actual emitting source of LWIR returning to the surface.
The SB Law applies to ALL matter absorbing and emitting energy. If you think otherwise, what law(s) of physics do you propose quantifies a different relationship between W/m^2 of planet emissions and the EQUIVALENT surface temperature? Keep in mind that the EQUIVALENT average surface temperature based on a BB analysis and the actual average surface temperature are virtually indistinguishable from each other. Even Trenberth acknowledges that this approximation is good enough.
The SB law relating the equivalent temperature to emissions is independence of a Planck distribution. Even a laser beam has an equivalent temperature based on its W/m^2. Relative to Earth, the planets emission temperature based on Wein’s displacement (which does depend on a Planck distribution) is close to the average surface temperature while the equivalent temperature of these emissions is only 255K because some of the energy in absorption bands is absent. This temperature matches the 255K temperature of the solar input which is very close to an ideal Planck spectrum where Wein’s displacement and SB get about the same temperature.
How can you explain this plot of the Earth’s behavior without acknowledging the relevance of the SB Law? The green line is the expected behavior based on the SB law for a gray body whose emissivity is 0.62 and the red dots are 3 decades of gridded monthly measurements of the planet’s emissions vs. the surface temperature aggregated into 2.5 degree slices of latitude. The larger dots are the averages per slice across 3 decades of satellite measurements. Repeatable tests of the prediction of SB are what convince me that SB must apply as the laws of physics require.
http://www.palisad.com/co2/tp/fig1.png
I frequently see both sides of the debate deny the relevance of the SB Law and this couldn’t be more wrong given how the planet actually behaves. Of primary importance is the T^4 dependence between W/m^2 and temperature which is ignored by the IPCC so approximate linearity between T and W/m^2 can be incorrectly presumed to represent the actual linearity required by Bode’s feedback model.
Of the terabytes of data I’ve studied from many sources, the relationship between the surface temperature and planet emissions as it conforms to a gray body whose emissivity is 0.62 is the most tightly regulated relationship there is. A consequence is that the 62% of the surface emissions that are emitted by the planet is nearly constant from pole to pole and land to sea and mostly independent of either temperature or insolation. Without clouds, the fraction is higher, with clouds it’s lower and the average clearly converges to 0.62.
A constant surface power gain of 1.62 (1/0.62) is the very definition of a linearity and confirms that superposition in the power domain is an undeniable truth.
You seem to forget Willis that the “upper atmosphere” is part of our planet. So moving the heat from one part of the planet to another part of the planet isn’t really cooling the PLANET.
…
The only way the planet can cool is via radiation.
Radiation is a lot easier when the heat is transported high up into the atmosphere.
The more rapidly heat is moved from the surface to the upper atmosphere, the more rapidly this radiation will take place.
You’re being silly. If the heat didn’t get moved from the surface to the upper atmosphere there would be far less heat to radiate away. If the heat remained at lower altitudes less would radiate away.
Hence, the movement of the energy so that it has a higher chance of radiating away certainly can be called cooling the planet.
The heat which is moved upward is in the form of water vapor. When it condenses to liquid water at high altitudes, it releases the heat of vaporization which was added at the earth’s surface by evaporation. This is mass transfer of material with potential energy (the heat of vaporization).
This relates to my question – ‘Moving surface air to the upper troposphere where it is above most GHGs and freer to cool to space.’ It is said to leave most of the GHG behind.
I thought that CO2 and air are a mechanical mixture with a small (approx 500ppm) concentration of CO2. What mechanism would cause the CO2 to separate so that it, as a greenhouse gas, would be left behind and NOT go with the rest of the air as it rises to the stratosphere and spreads?
I don’t recall hearing of a mechanism that would do this on a world wide scale (and I’m not talking about plants/animals metabolizing the CO2 and sequestering the carbon).
Willis, you cite:
“At an altitude of roughly 5-6 kilometers, the concentration of greenhouse gases in the overlying atmosphere is so small that heat can radiate freely to space”
I used to think like this, but after second thoughts, at that altitude it can also radiate DOWNWARDS.
A drop of water in the ocean surface will radiate upwards only, then some of it will be re-radiated by GHGs downwards. A drop of water high in the atmosphere, on the other hand, will freely radiate upwards to space (no GHGs to stop that) HALF of what it radiates AND will radiate downwards to surface the other half. Which in the end may be a similar situation than what we had at the ocean surface in terms of net emissions to outer space. Or am I mistaken?
Nylo: What do you think happens to the IR radiation that travels back to the surface? Does it warm the surface? If the surface is warmed what does that cause to happen?
From the height we are talking about, less than half of the radiation is back toward the surface. Calculate the angle the earth subtends at that height.
What’s blithely overlooked here is that heat escapes our planet much more readily from point B than from point A.
Don’t forget that half of the heat released in the upper atmosphere does not escape to space but goes in the opposite direction and strikes the surface.
Very little if any of the heat released in the upper atmosphere strikes the surface. Almost all, if not indeed all, of this down-welling radiation is re-absorbed by greenhouse gases and “Thermalized,” converting to heat absorbed by the atmosphere far far above the surface. The average Mean Free Path of 15-micron radiation is around 30 meters at the surface, gradually lengthening as altitude is raised, but radiation released at 5 kilometers has little chance of reaching even 1 kilometer altitude.
This non-controversial factoid completely invalidates the farcical Trenberth cartoon. The atmosphere cannot heat the surface, nor can it heat itself.
“he atmosphere cannot heat the surface”
….
WRONG…..happens all the time in the Northern Hemisphere.
….
When the wind is coming in from the South, it warms things up. This usually happens after a snow storm, when a southerly breeze warms the surface and melts the snow.
Now Michael, Trenberth did a good job. Willis has a more explanatory one he once published here on WUWT, and Judith Curry has one with the ranges. All very useful to those of us “in the audience”….
Mike Borgelt April 29, 2019 at 5:38 pm yes it warms the Surface, but via Radiation.
Sorry should sat NOT by LW Radiation.
DMac,
No one needs to explain this to ME. Professor Wang could explain it to YOU, if he is still with us.
Michael Moon: Why is the heat not “thermalized” to begin with? Why is it first radiated and *then* thermalized? A molecule that has absorbed heat radiation can do one of two basic things. It can re-radiate it or it can vibrate faster. In the first case some of the downward radiation will be sent back toward space. In the second case it raises the probability of a collision with another molecule thus transferring some of the heat energy to a molecule that can re-radiate it or pass it on.
Tim Gorman,
Radiation, once absorbed, can either be re-radiated or “thermalized.” At lower altitudes the atmosphere is denser, and thermalization is much more likely.
Actually, your question seems to confuse “heat,” which is the average kinetic energy of the molecules in a quantity of matter, with “radiation,” in this case long-wave Infrared.
What you mean by “thermalized” is not obvious. Are you saying that the increased “energy” of the molecule is passed on to a different molecule? If so then what keeps that other molecule from radiating away the increase in energy?
I’m not confusing anything. Energy is energy. A molecule that has absorbed energy can either pass it on through a collision with a less energetic molecule or it can radiate it away. It’s not any different than heating the air in a hot air balloon.
CDL –> Even assuming that 1/2 goes up, some percentage of that going “down” doesn’t reach the earth because it is a sphere. At 50,000 feet what is the percent that reaches back to the earth?
That would be true if clouds had zero thickness (or nearly so). Only then could the upward and downward radiation be equal.
As it is, the condensation occurs throughout a thick region of atmosphere. Radiation from the very top of the clouds to space is roughly half of the emitted radiation. The downward component, however, is fully absorbed by the clouds below it, warming them, and causing further vertical convection to the very top, where the reabsorbed heat is once again radiated.
This is a much more complex phenomenon than the discussion here reflects, IMHO.
Density matters.
Radiation travelling down is blocked, radiation travelling up isn’t.
CdL, you are looking at this too simply. You need to look at the total flow of energy instead of the direction of radiation. Once you get very high in the troposphere most of the energy directed downward gets reabsorbed quickly. It never makes it to the surface. Same is also true of much of the energy radiated upwards but it travels farther on average.
When you average this out you get most of the energy going into space.
CdL – As I and several other commenters have pointed out upthread, the fact that condensation occurs above most of the atmosphere makes a significant difference. See for example:
https://wattsupwiththat.com/2019/04/29/the-cooling-rains/#comment-2691736
but read thru the other comments as well.
Hi Willis,
I think few people understand just how vast the ocean is. I am in in Cabo San Lucas, out of San Francisco on a sailboat bound for Panama.
The depths, a few miles off shore, are 2-4 kilometers and it gets deeper as you go out. That is a lot of water.
A lot of water that buffers heat, CO2 and all manner of stuff we dump into it. Where did all that stuff come from. Well, the ocean and from land.
Anthropogenic? Maybe a little bit, but the ocean laughs at our hubris. Insignificant compared with natural processes.
Not very scientific, I admit. But common sense for mariners.
Keep up the good work!
Best regards,
Jim
Thanks, Jim. Indeed, the size of the ocean, and its buffering value, is almost unimaginable.
As a sailor, you might enjoy some of the sea stories over at my blog, Skating Under The Ice.
Stay safe on the ocean, one hand for the ship, one hand for you …
w.
R.I.P. “positive water-vapor feedback.”
So …. there ya have it. Trentberths missing heat is wrapped up in an increase in kinetic energy driving the increased rate of circulation of the tropics resulting in an increase in an extra 1.3 L of rainfall per meter.
Can we go home now?
Willis, I love your work and the idea that increasing rainfall will cool the earth is certainly worthy of investigation, but I think you may have gotten your units mixed up. You stated that “Figure 3 shows the annual change in rainfall, in millimeters per year, on a 1° latitude by 1° longitude basis” which was reported to be 1.33 mm per year from 1997 to 2015. But, then you do your calculations for the cooling caused by 1.33 mm of rain per square meter, not per 1° latitude by 1° longitude?
James, the increase in rainfall is 1.33 mm/year. Not 1.33 mm per year per 1°x1° of lat/lon. Not 1.33 mm per year per square metre. Just plain old 1.33 mm/yer.
To calculate the energy involved, it’s calculated in watts/square meter. So we have to look at how much energy is involved on a per square meter basis. This is equivalent to the amount of water evaporated (or condensed) per square meter, which is 1.33 liters per square meter.
w.
The math to get 1.33mm was done based on the 1-degree grids.
It isn’t a total of 1.33mm for the grid. It is across the entire grid. Think of it as water 1.33mm deep across the grid…it is still 1.33mm deep on a square meter area as well.
Just watching this Youtube video that just surfaced on Facebook https://www.youtube.com/watch?v=oYhCQv5tNsQ&feature=youtu.be&fbclid=IwAR2ey8K5n9MG3yXp2vHc-6kKiAL_cYlC-x5kLmH8jQDu9rmb15b49G9wu3E
Before wondering what it does to Earth’s average surface temperature, we should wonder what it does to the temperature record. Can you really treat the mean of min/max temperatures as an intensive property like concentration and calculate for areas with missing data?
Looking at those charts led me to observe that more rain falls where there are large mountain ranges. No surprise, as with prevailing westerlies the clouds rise and can’t hold as much water vapor. For example, Australia lacks a western mountain range, resulting in a very dry continent.
Well yes and no
There are no significant mountains along the West Australia coast but there is a warm current so the rainfall in SW Western Australia is anomalously high.
Equivalent locations in Africa and South America are desert. Southern California is semi-desert; San Diego has an average annual rainfall of less than 300mm.
Northern Australian rainfall is dominated by the summer Monsoon
Much of Pilbara is actually rather high. But it is the latitude, not the mountains that matter. Compare Australia with similar latitudes in South America which has a very high western mountain chain
Pilbara = Atacama desert. Atacama is actually a lot drier
Perth = Santiago. Both have similar mediterranean climate, good wine-growing areas.
Tasmania = Chiloe. Both very wet, temperate rain-forest
Willis,
You wrote, “I was also intrigued by how narrowly the rainfall is concentrated at the average Inter-Tropical Conversion Zone (ITCZ).”
Typo: ITCZ = Inter-Tropical Convergence Zone?
Cheers
Thanks, Boulder, fixed.
I hate typos.
w.
Well something must be wrong…I think I have got 2 meters of rain in my backyard this Spring! LOL
This is the wettest Spring I can remember here at this house. (about 20 years). It may be skipping the rest of Texas, but I think I could fill a lake with the runoff I have watched going past my house.
It must be global warming – after all they predicted this! (and ever other possibility)
April showers bring May flowers. I can remember very wet spring weather back in the 60’s.
Excellent article. Easy to see how your conclusion was reached.
Why do we not see more climate scientists dealing with real world measurements? It seems 99.99% of climate scientists concentrate on models and “tuning” them to meet some “global temperature”, however ephemeral that is. This just demonstrates how clueless the modelers are when it comes to writing equations that describe real world atmospheric conditions.
Climate scientists are basically only trained on models. Very little training on meteorological stuff. I do believe that is intentional.
Since CO2 is well mixed in the atmosphere, if you are above 90% of the atmosphere you are naturally also above 90% of the CO2.
The same goes for water, with the additional factor that cold air can hold less water, and the air at 50K feet is very cold.
I have no idea how this got down here, it was supposed to be a response to “nw sage April 29, 2019 at 6:31 pm”
The effect is much stronger for water since it condenses. Liquid or frozen water are not GHG:s, they are black-body radiators.
Just an off the wall conjecture. I wonder if this explains why they can’t find that “tropical tropospheric hotspot” . In other words the models are “right” but “wrong” because they don”t account for the cooling you just showed which obliterates the hotspot they were so sure must exist.
+50
Willis: another fine piece of thought-provoking analysis.
I’m fascinated by the increased rainfall over the 17-year life of the project, and I’m particularly fascinated by the fact that so much of the increase is concentrated in the equatorial Pacific. Very little in the Atlantic or Indian Oceans.
I wonder whether that increase was steady over the life of the project, or did it accelerate during El Niño years? Possibly even reverse itself a bit during the La Niña years? If you have the data handy, it would be interesting see if there was a correlation.
Hi Willis and Smartrock:
It would be very interesting to see how that extra precipitation varied over the time period 1997-2015, and indeed it would also be very interesting to see that precipitation plotted against the Nino3.4 index or SOI, as the period of this study had a large El Nino close to the start and a large La Nina two thirds of the way to the end (with some other ups and downs).
Also, UAH shows TLT in very wet years is warmer relative to surface temperatures (which are cooler during wet years), and the reverse in very dry years- at least over land area of Australia. Moisture carries heat high into the atmosphere where condensation releases it where a proportion is radiated to space- more in wet years than dry years. Am I right or am I left?
My location on the map of annual change of rainfall is coloured green: annual change + 6mm a year. I thought – that can’t be right, we’ve been in drought most of that time. So I went to the rainfall data for the nearest weather station. I live in Australia, in far western NSW, and the nearest station is Mildura in Victoria, about 30km away. In this area there is usually just one weather station, or less, within each 1 degree lat/long grid.
So, here is Mildura’s annual rainfall from Jan 1998 to Dec 2014 (easier than including partial years). The long-term average rainfall (1949-2019) is 286.6 mm.
A dry year (also 96/97): 1998: 162.8mm.
Above average: 1999: 339.0, 2000: 330.2.
The Millenium Drought – nine years, with just two at or above average: 2001: 186.8, 2002: 192.2, 2003: 303.8, 2004: 173.2; 2005: 277.8; 2006: 123.0; 2007: 223.0, 2009: 232.8; 2008: 201.4;
The drought breaks, and how – twice the average: 2010: 597.0; 2011: 658.
Back to below average: 2012: 214.4; 2013: 213.6; 2014: 256.8.
So, how do you get an annual increase of up to +6mm? That would be an increase of up to 102mm over those 17 years. But the trend over 1998-2014 is average, way below, way above, then below. The average of these years is 275.6 mm, not much below the long-term average. I can’t find the average 1949-1997 to see if that differs.
Mildura’s high rainfall of 2011 was exceptional; 155mm (6 inches) fell in one day, 5 February, actually in just a couple of hours in the early morning – part of my roof collapsed, and there was major damage to roads and buildings. This was a genuine tropical downpour, the remains of Cyclone Yazi, which had hit Cairns nearly 3000km northeast. It moved inland, turned into a storm depression, was captured in the NW-SE trough across the continent and dropped its bundle on us.
Since 2014, the rainfall has been: 2015:240; 2016: 358.6; 2017: 269.6; 2018: 135mm. We are back in drought: in the first four months of 2019, there has been just 9.8mm (2004 was comparable with very low rainfall for the first four months).
This is just one location, but I am fairly sure that if I crunched the numbers for all that green area in Australia, the result would be the same, extremely variable rainfall, with no real evidence of an overall increasing trend.
Does Satellite IR sensing have enough resolution to detect this proposed “up to” 1 Watt/m^2 increase in net outgoing IR over the last decade from increasing ITCZ “storminess”?
If it does, we would have heard about it…No?
If it doesn’t, then the satellite measurements of reduced outgoing IR on the order of 0.6 Watts/m^2 from increasong CO2 over the last decade would also not be detectable.
Is that data available?
Perth coastal ranges get a metre a year and more. Not shown in your first maps.
Very localized as you will know if you are familiar with the area, once over the escarpment the precipitation drops very sharply. A hundred miles inland and you find salt flats.
The warmistas will not like:
**Which means that over that period and that area at least, the calculated increase in warming radiation from GHGs was more than counterbalanced by the observed increase in surface cooling from increased evaporation.**
Willis:
Delighted that, at last we are discussing the influence of water on the environment. My long standing hypothesis being that the earth sweats to keep cool, just like we humans do, with the thermodynamics giving a great deal of support to this.
Delighted also that we have now, thanks to you Willis, a value for the increase in evaporation at some 1.33 mm/yr. over the period. The calculated upwelling of energy thus being correct at 0.104 Watts/sq.m.
I would, however be grateful for details of the IPCC calculation on the equivalent figure for downwelling change due CO2. This, for me has been lost in time and appears somewhat dubious. The calculation you give being somewhat sparse.
Back on earth we have good experience on what happens in this sort of situation as seen in the behaviour of our steam generating plants. These operate at constant temperature and pressure (generally as our climate?) and respond to an increase in energy input by an equivalent output of energy; all in balance. Similarly, I suggest with the climate in the presence of water.
Thus, back engineering this proposal we can suggest that the downwelling change (+ other) energy must be in balance at some 0.104 Watts/sq.m, or thereabouts subject to leads/lags etc.
This then leads to the question: If the IPCC reckon CO2 is responsible for a mere 0.06 Watts/sq.m, where does the OTHER 0.044 Watts/sq.m come from.?
Difficult to answer; but with many possibilities of which Albedo is one with solar and volcanic activity also on the list – all basic natural processes in which water itself also plays a part as a known greenhouse gas.
On a side issue: You say “This thermal circulation is greatly sped up by air driven vertically at high rates through tall thunderstorm towers.”
IMO a good proportion of this is due to the buoyancy of water vapor wrt dry air in conjunction with the thermal differential.
I have attempted to get a handle on this aspect by calculating the forces and potential velocities involved here; but am floundering a bit ! Any ideas on this.?
Generally I find that these buoyancy/thermal aspects get conflated in many papers and lead to incorrect assumptions in my view.
Enough for now. Very much appreciate your contribution.
Regards
Alasdair.
PS: There is a not very good paper on this on my htp:// cognog2.com site; but I am not good at computer presentations., although it does give the basics.
Willis:Re your concluding paragraph.You make no mention of the water-air interface temperature change with increasing LWR due to CO2. The evaporative flux is controlled by the interface temperature, which must be calculated from a surface energy balance–which shows that an increase in LWR goes mainly to reduce.the heat loss from the ocean,not to increase evaporation.Your “analysis” simply ignores the role played by ocean heating.
For a relevant tutorial you can try http://www.temporalpublishing.com Click on STORE,Choose the text “Basic Heat and Mass Transfer”. Then click on Instructor and choose Supplementary Material,and then Supplements for Heat and Mass Transfer from the drop down sub-menu.See Supplement 8,in particular Section 8,pages 68-72.
AND:
Ocean evaporation is nearly 100% solar energy driven. ITCZ water temperatures rise on the order of 5 to 8 degrees every morning FROM NEARLY A KILOWATT OF DIRECT SOLAR RADIATION per m^2. A fraction of a watt/m^2 of LWIR back radiation is totally lost in the noise…even if LWIR were efficient in raising surface temperatures.
super cell thunderstorm height max at 20.7km
air pressure at 20.7km is 3.7kPa
@ur momisugly t=-56°C
co2 dia 0.7*10^-10m
http://hyperphysics.phy-astr.gsu.edu/hbase/Kinetic/menfre.html#c3
this gives a mfp of .34*10^-4m
Continuing on
The time between collisions is 340ns
giving 2.9e6 collisions per second
time from the absorption of a photon by co2 to emission as another photon is microseconds (around 2us).
So it is 10 times more likely that the excited co2 molecule will transfer energy to other molecules by collision. even at 20km.
GHG concentration is low so the energy will likely be passed on to non-ghgs and will not be radiated until the energy is passed back to a GHG molecule (note that water vapour will be very low at this altitude and temperature). This leaves CO2 as the major radiator.
Note that there is still a vertical way to go before a ghg can radiate to space without encountering other ghg molecules.