Researchers find new mechanism to explain the birth of cloud droplets

Posted: March 27, 2016 by oldbrew in Clouds, modelling, research
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Cumuliform cloudscape over Swifts Creek, Australia [image credit: Wikipedia]

Cumuliform cloudscape over Swifts Creek, Australia
[image credit: Wikipedia]


Climate modellers know less about cloud formation than they thought they did, according to new research.

There is enough known about cloud formation that replicating its mechanism has become a staple of the school science project scene. But a new study by scientists at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) reveals that much more is going on at the microscopic level of cloud formation than previously thought.

The scientists determined that organic molecules effectively depressed the surface tension of the water, allowing for more efficient formation of bigger cloud droplets. “Conventional wisdom says that the water solubility of the aerosol is the key factor in the formation of cloud droplets,” said study senior author Kevin Wilson, the deputy director of science at Berkeley Lab’s Chemical Sciences Division.

“The more easily a particle dissolves in water, the easier it is for a cloud droplet to form. What we’re finding is that relying upon solubility alone doesn’t always work. Our study suggests that what the aerosol is doing at the interface with water is what matters in accurately predicting whether it will go on to form cloud droplets.”

The findings, to be published in the March 25 issue of the journal Science, could improve the accuracy of climate change models that predict the potential cooling effect of reflective clouds based upon the particles in the air.

“Accurately describing the connection between the chemistry of aerosol particles and the formation of cloud droplets remains difficult, and it is a key challenge for models to correctly predict climate,” said Wilson. Wilson worked with study lead author Christopher Ruehl, who did the research while he was a postdoctoral scholar; and co-author James Davies, a current postdoctoral scholar at Berkeley Lab.

Full Phys.org report: Researchers find new mechanism to explain the birth of cloud droplets

The report then goes on to look into the technicalities in more detail.

“The role of inorganic and organic aerosols in cloud formation has been a highly contentious issue that’s been argued about for many years,” said Wilson. “Based on the paper’s findings, I would say that these surface interactions play a central role in cloud droplet formation, and that they should be considered in climate models.”

Comments
  1. erl happ says:

    Re cloud. Consider this: Earth is 3% closer to sun in January and yet this is when the average temperature of the Earth as a whole is coolest. It is at this time that cloud albedo is greatest.

    Obviously cloud feedback is negative. Clouds reflect more energy than they trap. Cloud can reflect up to 90% of incident solar radiation.

    Atmospheric absolute and relative humidity changes over time. Mostly according to transpiration by vegetation. More vegetation will see it recover from a long period of decline.

    Humid air travels polewards on westerly winds.

    The velocity and carry of the westerly winds varies over time and with it the latitudional position of the frontal systems that elevate moist air giving rise to dense cloud.

    The surface pressure differential between the mid latitudes and the polar regions in the southern hemisphere has been increasing for seventy years.

    The mid latitudes in the southern hemisphere have been warming and the high latitudes of the southern hemisphere have been cooling. Antarctic Ice are has increased as the mid latitudes have become drier.

    Clouds are not climate neutral..Cloud cover is forced by ozone heating of the air in high pressure cells. Ozone levels vary over time. There is a signature in the surface temperature record indicating that temperature variability is greatest in January between the Arctic and 30° south and in July in the remainder. That’s when stratospheric ozone varies most strongly..

    Ned Nikolov, I am curious about this statement of yours on another post re cloud: ‘ While true that the cloud cover can be influenced by solar magnetic activity’ . Have you chapter and verse?

  2. tallbloke says:

    Erl, I think near-tropopause humidity is affected by solar-magnetic variation.

    Here’s the correlation I found:

  3. David A says:

    Earl, do not forget that the sun at this time is also predominately in the southern hemisphere, thus more SW radiation which does reach the surface goes below into the oceans, thus, for a time, is not in the atmosphere as well.

  4. erl happ says:

    Tallbloke, What’s the specification on ‘near troposphere’?

  5. erl happ says:

    David A. The reason for the increase in cloud cover in southern summer is the marked cooling of the atmosphere as the continental landmasses of the northern hemisphere emit much less radiation into the atmosphere than they do in northern summer. So, its simply a function of the temperature of the atmosphere. Reduce the temperature of the air and you get more cloud.

    The corollary is that a loss of cloud cover in southern summer results in a greater addition to the Earth’s energy budget than if the same amount of cloud cover were lost in June. There is simply more ocean and its more directly under the sun to absorb the extra radiation when cloud is lost in January.

  6. J Martin says:

    But is it absorbed by the ocean ? I thought the infrared is simply turned into evaporation and clouds, the remaining frequencies being absorbed, UV in particular.

  7. erl happ says:

    J Martin, First time I’ve seen that proposition. Very little UV gets through the atmosphere. Cant see why infrared or any other wave length should be exclusively responsible for evaporation.

  8. David A says:

    The SW is not lost to earth’s system, but , for a time, to the atmosphere as it penetrates the ocean surface up to 800′ and can stay in the ocean for decades. J. Martin is correct that much of the LWIR (mostly B.R, is absorbed at the ocean surface, and, watt for watt, a much higher percentage of same energy is used up in evaporation and acceleration of the hydrological cycle, as compared to SW insolation.

  9. erl happ says:

    J Martin and David A. I’m not convinced. Perhaps if the temperature of the ocean were closer to the point where extra energy produces steam but not otherwise. The issue is discussed here: http://www.drroyspencer.com/2014/04/can-infrared-radiation-warm-a-water-body/

    I’m with Roy. I would need a demonstration.

    Wind and surface disturbance that increases surface area is the most important factor affecting the rate of evaporation I would have thought. The relative humidity of the air would also be important.

    So far as the rate of acquisition of energy by the ocean is concerned just remember that cloud can reduce incident energy at the surface by 90%.

    In any case the relevance of the comment escapes me. Global albedo is greatest in January when available energy from solar radiation is 3% greater than in July. That’s when the Earth is coolest. Clouds represent a negative in terms of energy acquisition, not a positive and any back radiation effect from whatever spectrum is involved is patently and demonstratively a minor matter in the scheme of things..

  10. oldbrew says:

    The thick clouds on Venus don’t stop the surface being hot.

    ‘Temperatures on the surface of Venus approach 475 °C, and the atmospheric pressure is 93 times what you experience here on Earth.’

    ‘The clouds we see on Venus are made up of sulfur dioxide and drops of sulfuric acid. They reflect about 75% of the sunlight that falls on them, and are completely opaque. It’s these clouds that block our view to the surface of Venus. Beneath these clouds, only a fraction of sunlight reaches the surface.’
    http://www.universetoday.com/36871/clouds-on-venus/

    What effect if any do clouds have on the relationship between temperature and pressure?

  11. erl happ says:

    Oldbrew, Just thinking now: There is a relationship between surface pressure and temperature that has perhaps three modes of influence and clouds are part of the picture. This is the way I see it.
    1 Increased pressure means warmer air. Is this why Venus is warm? Are there zones of ascent and descent. This is the bike pump effect. Can only produce an increase in surface temperature if a planet as a whole or part of a planet gains atmospheric mass.
    2. Surface pressure relationships determine where the wind comes from and on a planet that is warm in one place cold at another there is a close relationship between the origin of the air and its temperature. In particular the mid latitudes of the northern hemisphere will vary in temperature according to whether the winds are South Westerlies of subtropical origin or north Easterlies of polar origin. So you can warm and cool the surface by changing pressure relationships.This mode is called the Arctic Oscillation, The North Atlantic Oscillation or simply the Northern Annular Mode.
    3. High surface pressure means cloud free skies. Increase the mass of air that is descending and the pressure rises little but the cloud free area gets larger. High pressure cells are relatively ozone free areas but as ozone descends it warms the air and clouds evaporate. So, shift atmospheric mass from high latitudes (where pressure falls) and in consequence all other latitudes gain atmospheric mass and will become warmer due to 1, 2 and 3.

    If the ozone content of the stratosphere rises there is increased contrast in temperature and density between masses of air that are ozone rich and ozone poor. Ozone builds in the winter hemisphere. Ozone heating produces upper level troughs that strengthen and become polar lows. Increased ozone results in lower surface pressure in higher latitudes and increased surface pressure in the mid latitudes………the cause of the modern warming. South of 50° south surface pressure fell by 10 hPa between 1948 and 1998….and is now recovering.

    In the late 1890’s the French balloonist de Bort discovered that the tropopause was several kilometres lower when surface pressure was low. Dobson, in the 1902s discovered that total column ozone was 20% higher on the margin of a high pressure cell than at its core….in fact total column ozone mapped surface pressure and meteorologists in the past relied on this data to make forecasts.

    RM Goody 1954 ‘The Physics of the Stratosphere’ in chapter 5 WINDS AND TURBULENCE began with these words: The subject of hydrodynamics of the stratosphere is growing to be one of importance to synoptic meteorology. The idea is now gaining ground that, from the dynamical standpoint, the stratosphere and the troposphere should be treated as a single entity.

    Goody observed, following Dobson’s work that wind strength increases with height in the troposphere and there is a sharp maximum at the tropopause, above which it decreases with height, certainly as far as 14km. There is no change in wind direction at the tropopause. meteorologists today recognize that the synoptic situation is driven at the 250hPa level rather than at the tropopause.

    The energetics that drive the planetary winds and surface pressure are mapped as the jet streams in the middle of the interaction zone between the stratosphere and the troposphere at 250hPa.

    In the 1950’s climate science was poised to understand the source of natural climate variation. Somehow, at that point the plot was lost.

    From Wikipedia: Sir John Houghton was the co-chair of the Nobel Peace Prize winning Intergovernmental Panel on Climate Change’s (IPCC) scientific assessment working group. He was the lead editor of first three IPCC reports. He was professor in atmospheric physics at the University of Oxford, former Chief Executive at the Met Office and founder of the Hadley Centre. Houghton took over from Dobson at Oxford as the mover and shaker of research activity in the 1960’s.

    The golden thread that depended on validating the essential question ‘Is it true’ was broken.

  12. David A says:

    Erl, IMV, your thoughts here are over black and white. The discussion on the capacity of LWIR to warm the oceans is certainly far too black and white. The question is not, can they, but how much compared to an equal watt per sq. meter of SW radiation? Usually one side says they can, the other says they cannot, neither admits to ignorance.

    More specifically for example take an additional 70 watts per sq. meter of short wave insolation (there is about 6 percent more January insolation vs July, not three percent) vs. say an increase of the same 70 watts per sq. meter insolation of LWIR. (Ignore for a moment that this is TOA, not surface)

    Remember this law; Only two things can change the energy content of a system in a radiative balance; either a change in input, or a change in residence time of some aspect of the energy within the system.” and its corollary; “The residence time depends on both the materials encountered, and the WL of the watt under consideration.”

    Why is this law, and its corollary true? Because energy is indestructible! Because under an assumed non changing input, ANY increase in the residence time of energy in the system, will invariably increase the energy content of the system, as any decrease in the existing residence time of same energy IN the system, will lower the energy in the system.

    Erl, you stated this…
    ================
    “Global albedo is greatest in January when available energy from solar radiation is 3% greater than in July. That’s when the Earth is coolest.”
    ================

    I disagree. We can only state with certainty, “That is when the atmosphere is coolest.” The atmosphere is a thin membrane between the oceans, with at least one thousand times greater energy (how did that energy get there?) and the source of the vast majority of the oceans energy and the only exit for the earth’s energy, the Sun and space. It is a short tail being waged between two large dogs.

    Let us further examine the question of how disparate W/L insolation warms in relationship to residence time.

    What about the average “residence time” of the packets of energy arriving from the Sun? Clearly, some Short Wave packets would be absorbed and immediately emitted as Long Wave, but, since absorption and emission take time, they would have a longer “residence time” in the Earth System than the reflected Short Wave packets of energy in case.

    Furthermore, some packets of Short Wave energy would be absorbed and would warm the Surface and remain in the Earth System for longer times. Therefore, it seems that higher Surface temperatures and longer “residence times” have something in common.

    Now to the actual Earth System, with water and GHGs, and weather, etc. Some packets of Short Wave photon energy are reflected and therefore have very short “residence times”. That constitutes about a third of the incoming Solar energy.

    The remaining two-thirds of Solar energy packets are absorbed by the Atmosphere or the land or ocean Surface and cause the Earth System to warm. The energy in some packets is immediately emitted as Long Wave radiation and some of that passes freely through the Atmosphere ten-micron window and is lost to Space, with a relatively short residence time.

    However, much of the incoming Solar energy packets that are absorbed by the land and ocean Surface remain there for some time. Furthermore, some of the energy packets that are emitted from the Surface happen to be at wavelengths where the GHGs make the Atmosphere opaque (namely the seven-micron band absorbed by H2O and the fifteen-micron band absorbed by both H2O and CO2. About half of those energy packets get re-emitted back towards the Surface and even some of those emitted towards Space are intercepted and absorbed by yet other GHGs and re-emitted, etc.

    Of course, given convection (thunderstorms, winds, etc.), evaporation, and conduction, much of the Solar absorbed by the Surface is transferred to the Atmosphere by non-radiative means. Nevertheless, even those energy packets must be transformed into radiative form to finally leave the Earth System as Long Wave radiation to Space.

    Thus, if you followed the energy in a given packet from the Sun, some and perhaps most of those packets would have very long “residence times” in the Earth System.

    So clearly, clouds are capable of both increasing the residence time of some LWIR radiation from the surface, and decreasing the residence time of SW insolation from the Sun. The net effect is dependent on both the amount of energy affected, and the residence time of the energy affected, which is dependent on both the WL of the energy, and the materials said energy encounters.

    It is true that 100 watts per sq. M of SWR, has the same energy as 100 watts per sq. M of LWIR, however their affect on earth’s energy balance can be dramatically different. In this sense, not all watts are equal.

    For instance lets us say 70 watts of LWIR back radiation strikes the ocean surface. Much of that energy then accelerates evaporation (Erl, it must as it absorbed at the surface) where said energy is lifted to altitude, and then condenses, liberating some of that energy to radiate to space. It is certainly true that temperature has a great affect on evaporation. This does not deny other affects you mention, but again, we cannot be black and white.

    Now lets us assume the same 70 watts per sq. M strikes the ocean, but this time it is composed of SWR, penetrating up to 800 ‘ deep ( the epipelagic Zone ) and some even deeper to 3000′
    (Mesopelagic Zone) A lower percentage of the SW insolation is absorbed at the surface, therefore relatively it must have less affect on evaporation relative to S/W of equal wattage, and, due to deeper penetration,a far longer residence time and therefore warming or cooling potential.

    Some of that energy may stay within the ocean for 800 years. The SWR has far more long term residence time energy, and even warming potential then the LWIR. Over five relatively strong solar cycles the potential is for a great percentage of this increased visible and S/W insolation to increase energy in earths system for every day and month and year of this input change relative to five weak solar cycles. GHG flux cannot make nearly so much of a direct (exclude for now feedbacks) long term affect as the residence time change is vastly shorter.

    The problem is none of this is quantified in such discussions, and CAGW science, despite spending billions annually, does not even begin to examine such questions as …

    What is the residence time of disparate W/L insolation in earths land, oceans and atmosphere?

    What affect in total system energy accumulation does the known change in solar cycle insolation W/L have? (Although insolation may change little, the change in the percentage of short W/L vs. longer W/L may have a great cumulative effect.)

    How much energy is added to earth’s system (primarily oceans) by five successive strong solar cycles, vs. five short solar cycles?

    How much does an equal amount of LWIR increase evaporation, vs. an equal amount of SW insolation?

    How much energy is absorbed below the SW selective ocean surface, vs. the same amount of energy from a LWIR source?

    Does the earth gain or lose energy in the SH summer, vs the NH summer?

    I.M.V. these questions need to be answered to begin to say we understand our very complex climate.

    Cheers
    David A

  13. David A says:

    Oldbrew, I would encourage a thought experiment. Answer (or at least think about) your own question for the affect of clouds and atmospheric pressure on Venus in terms of residence time of energy in the system.

  14. oldbrew says:

    Lapse rate isn’t dependent on residence time AFAIK. No mention of it here.
    http://en.wikipedia.org/wiki/Lapse_rate

  15. michael hart says:

    Only climate science could suddenly ‘discover’ the world of organic surfactants. I’m no etymologist, but I’ll hazard a guess that the word surfactant has been in common-English dictionaries for a century, and there are $multi-billion industries that make extensive use of chemicals with such properties.

  16. erl happ says:

    David A, I know of no source of variability in the proportion of infrared in relation to the total of all radiation reaching the surface of the sea.

    Yes, my 3% should be 6%.

    Average sea surface temperature for the last 68 years is 12.92°C in January and 16.2°C in July. Near surface air is on average about 0.6°C cooler than the surface of the sea.

    The Earth is 3°C cooler when solar radiation is 6% stronger. That tells me that It is cloud cover that is responsible for surface temperature variation not the flux in radiation or change in its components.

    The sea is transparent and therefore absorbs and holds energy to depth. The land heats strongly at the surface and returns that energy to the atmosphere largely within the 24 hour cycle, incidentally increasing the moisture holding capacity of the air and in the process reducing cloud cover resulting in an average temperature that is almost 3°C warmer when the suns radiation is 6% weaker.This is a product of the distribution of land and sea between the hemispheres. Doesn’t matter what the source of the variation in atmospheric temperature is…..If the atmosphere heats from whatever source cloud will fall away, and more radiation reaches the surface.

    Yes, that’s pretty black and white. What it says to me is that atmospheric moisture and its product ‘cloud’ is a negative feedback on surface temperature. Add moisture to the atmosphere and the surface will cool.

    Now, if the ocean is warmed by more radiation from whatever source it is plain that the rate of evaporation can never increase to the extent that cloud cover actually increases to curtail the rate of increase in energy entering the system. So,this is a potential runaway situation that is curtailed by the change from summer to winter and solar radiation falling away allowing cloud cover to build again. Saved from a fiery furnace by the tilt of the Earth’s axis.

  17. David A says:

    oldbrew, variations in lapse rate occur partially due to disparate rates of convection. Motion and space and time (here residence time) are always interdependent variables. Move warm air more quickly upwards and you shorten residence time oof the system as a whole. Lapse rate is a description of an observation of energy/temperature change WITHIN the system. Change the rate of movement through that system, you change the energy content within it.

    But it s more involved then that. Think of the residence time of energy entering a system with no atmosphere, vs. one with a heavy Venusian like atmosphere. The atmosphere itself is a pool that contains energy. The greater the pool, the more energy it is capable of containing. The insolation entering the Venusian atmosphere would not hang around, increasing under constant input while input remains the same, without this large pool of atmosphere to hold it.

    The greater the density of molecules, even if the same T of a less dense atmosphere, the more energy per sq. meter, the higher a thermometer will register as more molecules strike the observational instrument. A denser atmosphere is a larger storage pool per sq. meter, increasing the capacity of that pool to hold energy.

    FWIW

  18. oldbrew says:

    A larger atmosphere means higher pressure at the surface, hence higher temperature (than a smaller atmosphere).

    Of course you have to adjust for relative distance from the Sun.

  19. erl happ says:

    David A This makes sense: ‘A denser atmosphere is a larger storage pool per sq. meter, increasing the capacity of that pool to hold energy.’

    And what Oldbrew says about surface pressure also makes sense. Just a different way of expressing the same proposition.

    Lets look however at the question of variations in lapse rate.

    You suggest they occur partially due to disparate rates of convection.Disparate rates of convection find expression in wind speed as measured in the horizontal plane, very familiar to surface dwellers and turbulence that is familiar to people who travel in the lower stratosphere.

    Wind speeds depend upon the pressure gradient. So, a five mb pressure gradient will provoke a stronger wind if the extremes of low and high surface pressure are say 1000km apart than if they are 10,000 km apart.

    The strongest winds are the Jet stream winds located where there are the steepest gradients in density of the air in turn due to differences in ozone composition. We see these strong winds at 300 hPa through to 70hPa at the interaction of the stratosphere and the troposphere and throughout the stratosphere in winter.

    Lapse rates are affected by
    1. release of latent heat of condensation.
    2. Air density.
    3 differences in the population of absorbers between air masses.

    The opacity of ozone as an absorber of long wave at 9-10um is pressure dependant. I have read that as much infrared energy is absorbed by ozone in the troposphere as in the stratosphere.

    Uniquely, ozone is not well mixed. Other absorbers of Earth emitted infrared are well mixed.

    Dobson found that ozone mapped surface pressure. Just think for a moment about the implications of that observation.

    Wind at the surface is a response to differences in the ozone composition of the air above the point where ozone begins to change lapse rates, about 300hPa in the mid latitudes getting ever lower as one approaches the winter pole.

    Surface temperature responds to wind direction.

    Just think it through and where does it take you?

  20. David A says:

    Erl, please understand that I agree that clouds are net cooling. I also understand that the system responds with a negative feedback to increased insolation, accelerating the hydrological cycle, increasing albedo. Willis E at WUWT did some good work on this and the limitation of tropical SST.

    Where we disagree, or where you make a positive assertion, and I maintain that we do not know is as follows. Again you stated, “The Earth is 3°C cooler when solar radiation is 6% stronger.” Yet you did not note my previous comment above saying, “I disagree. We can only state with certainty, “That is when the atmosphere is coolest.” followed by some thoughts in regard to this increased insolation first pouring into the SH ocean. In the SH summer we go from more intense insolation striking the 80 some percent ocean SH more directly, to the NH summer where there is far greater land surface immediately warming and sending that energy back to the atmosphere via radiation and conduction.
    The energy going into the oceans in the SH summer has a far longer residence time then the solar spectrum striking land.

    So my questions remain unanswered…

    Does the earth (Land, OCEANS and atmosphere) gain or lose energy in the SH summer, vs. the NH summer?

    What is the residence time of disparate W/L insolation in earths land, oceans and atmosphere?
    (This is very complex of course, but certainly cogent)

    What affect in total system energy accumulation does the known change in solar cycle insolation W/L have? (Although insolation may change little, the change in the percentage of short W/L vs. longer W/L may have a great cumulative, over time effect.)

    How much energy is added to earth’s system (primarily oceans) accumulate by five successive strong solar cycles, vs. five weak solar cycles?
    (consider residence time here in particular. An increase of a particular solar wave length which is not absorbed in the atmosphere or at the surface, but penetrates deep into the oceans, may, relative to a previous cycle, accumulate daily every day for the entire decade or five decades almost 100 percent of the energy of that particular spectrum.)

    How much does an equal amount (Watt per meter sq.) of LWIR increase evaporation, vs. an equal amount of SW insolation?

    How much energy is absorbed below the SW selective ocean surface, vs. the same amount of energy from a LWIR source?

  21. erl happ says:

    David: You say: I also understand that the system responds with a negative feedback to increased insolation, accelerating the hydrological cycle, increasing albedo. I say increased insolation reduces albedo due to atmospheric heating and the lag in evaporation.

    Re: “That is when the atmosphere is coolest.” I refer to the global atmosphere, not the southern hemisphere atmosphere and global Sea surface temperature not local.

    Re: more intense insolation striking the 80 some percent ocean SH more directly…..no, my point is that globally insolation is truncated by cloud cover in northern summer. In southern summer Northern hemisphere is cooler because its in winter and cloud cover markedly increased. Annual range is much greater in the northern hemisphere. Not sure whether southern hemisphere receives that much more insolation in summer than winter because some of that increased cloud cover due to a cooling atmosphere no doubt spills into the southern hemisphere. The increase in insolation striking the southern hemisphere in summer is much less than in the northern hemisphere in the comparable season.

    Does the earth (Land, OCEANS and atmosphere) gain or lose energy in the SH summer, vs. the NH summer?…..Dont know, but inter-annual variations in cloud cover associated with ozone driven shifts in atmospheric mass engineer large change in cloud cover when cloud is most abundant, the Arctic winter. On an interdecadal scale it is the Antarctic that drives the ship.

    What is the residence time of disparate W/L insolation in earths land, oceans and atmosphere?
    (This is very complex of course, but certainly cogent)

    I don’t think ‘residence time’ is a useful concept. Does water have residence time in a bucket? Heat energy in the oceans?

    What affect in total system energy accumulation does the known change in solar cycle insolation W/L have? (Although insolation may change little, the change in the percentage of short W/L vs. longer W/L may have a great cumulative, over time effect.)….Total solar irradiation is relatively invariable, proportion of short wave energy in the total increasing with sunspot activity. However, variation in short wave expresses itself in the inflation of the atmosphere, the ionization of oxygen and nitrogen that produce antagonistic effects.The important thing is the result in terms of ozone levels in the stratosphere.

    How much energy is added to earth’s system (primarily oceans) accumulate by five successive strong solar cycles, vs. five weak solar cycles? …… Depends upon the flux in cloud cover driven by surface pressure related to the ozone content of the air in the interaction layer between the troposphere and the stratosphere.

    How much does an equal amount (Watt per meter sq.) of LWIR increase evaporation, vs. an equal amount of SW insolation? ….Suspect that any change driven by this factor is completely overwhelmed by more potent influences.

    How much energy is absorbed below the SW selective ocean surface, vs. the same amount of energy from a LWIR source? …….A point of esoteric interest. It can be established that downwelling long wave has an immaterial effect on the temperature of the air below the point of emission. I suspect the same applies to water.

  22. David A says:

    Erl, I do not think we are making much progress. The oceans contain one thousand times the energy of the atmosphere, in a greatly reduced amount of space! The vast majority of that energy is solar driven input! Residence time is crucial to all temperature systems, as it is the only means by which temperature changes under constant input in a balanced system.

    There are huge checks and balances, such as you describe in your TOA discussion of ozone, but as I said in my first comment, we have not quantified these checks and balances that are, in and of themselves immensely more powerful then the tiny affect of CO2.

    You describe the cooling of the NH land mass as the reason for a cooler atmosphere during the SH summer. This is true, but only part of the picture and orthogonal to other powerful affects and reasons. You also have the entire southern hemisphere receiving 30 to 50 watts increase in insolation, tens of millions of square miles of ocean, receiving increased and more direct insolation. This input is also responsible for increased cloud cover and humidity. Also in this vast southern Hemisphere oceans, you have trillions of joules of energy no longer stopping at the surface, like in the NH summer, but also not entering the atmosphere, for a TIME, but going below the ocean surface. This immense changes with huge potential feedbacks can not be dismissed without quantification.

    Regarding residence time you say,
    =============================
    I don’t think ‘residence time’ is a useful concept. Does water have residence time in a bucket? Heat energy in the oceans?”
    =============================
    My goodness, of course it does. All non-input change theories on climate are a manifestation of the affect of “residence time.” For instance, the GHE is based on increasing the residence time of certain WL of LWIR energy via redirecting exiting LWIR energy back into the system, while input remains constant, thus more total energy is within the system. The greater the increase in residence time of the energy, the greater the potential energy accumulation. “Only two things can change the energy content of a system in a radiative balance; either a change in input, or a change in residence time of some aspect of the energy within the system.” Every ozone TOA change you describe, is either a change in residence time of some portion of the atmosphere, or due to a change input, solar insolation, or a combination of the two.

    Let us take your water in a bucket analogy. Imagine a tall barrel with a constant stream of water flowing in at the top, and a hole at the bottom. The level of water in the barrel will rise until the pressure of the weight of water at the exit hole is sufficient to match the rate of water exiting to water entering.

    Let us analogize:
    a) the level of water in the barrel to the temperature of the Earth System,
    b) the rate of the stream of water coming in as Sunlight energy in, and
    c) the rate of the stream of water exiting as Infrared radiation energy out to Space.

    Once the system stabilizes such that (b) is equal to (c), we can see that “residence time” of the average drop of water is proportional to the level of water in the barrel. The only way to change the level of the water in the barrel if input remains constant, is to change the residence time of the water in the barrel.

    The analogy to the earth’s system is exact, as energy cannot be destroyed, so mathematically it works in a simple fashion;…
    Numbers are simplified to a ten basis, for ease of math and communication. Picture the earths system (Land, ocean and atmosphere) as a one lane highway. Ten cars per hour enter, (TSI) and ten cars per hour exit (representing radiation to space.) The cars (representing one watt per square meter) are on the highway for one hour. So there are ten cars on the highway. (the earth’s energy budget)

    Now let us say the ten cars instantly slow to a ten hour travel time. Over a ten hour period, the energy budget will increase from ten cars, to 100 cars, with no change of input. Let us say we move to a one hundred hour travel time. Then there will be, over a one hundred hour time period, an increase of 990 cars. The longer the residence time on the highway, the more cars.

    Of course the real earth has thousands of lanes traveling at different speeds, and via conduction, convection, radiation, evaporation and condension, albedo changes, GHGs, etc, etc, trillions of cars constantly changing lanes, with some on the highway for fractions of a second, and some for centuries, some slowing down the traffic on certain lanes (The CO2 affect at 15 microns) but at the same time limiting input to other slow traffic lanes, (W/V reducing surface insolation even in clear sky conditions.) Also The sun changes W/L over its polarity cycles far more then it changes total TSI. Additionally the sun can apparently enter phases of more active, or less active cycles which last for many decades. Many of these immense changes are orthogonal, others directly cross paths.

    Without observing and reasonably QUANTIFING all of the above, TOA to depth of oceans, we are perhaps foolish to say we know.

  23. erl happ says:

    David A.
    ‘The oceans contain one thousand times the energy of the atmosphere’…. Agreed.

    ‘You also have the entire southern hemisphere receiving 30 to 50 watts increase in insolation, tens of millions of square miles of ocean, receiving increased and more direct insolation. This input is also responsible for increased cloud cover and humidity.’ ….obviously there is the hydrological cycle, moisture evaporating into the atmosphere….but one hell of a lot more from photosynthesising plants than the surface of the ocean. Consider the difference in surface area, plant leaf area versus area of the standing bodies of water. When the land masses of the northern hemisphere return energy to the atmosphere in northern summer atmospheric moisture falls away despite the surface area of photosynthesising plants that come alive when the temperature rises into the zone where they can actually do some work….hence the seasonal reduction in atmospheric CO2 at that time of the year. Consider the balance between the area of the southern oceans as a sink for solar energy by comparison with the leaf area of photosynthesising plants in the southern hemisphere. In fact in southern summer much less energy gets back into the atmosphere in the south by comparison with the north allowing cloud cover to be maintained rather than increased as all that potential evaporation doesn’t happen for the lack of a mechanism to convert energy into atmospheric water vapour. .Call it residence time if you wish. Its energy that is stored rather than driving evaporation or photosynthesis. So, I think the hydrological cycle is somewhat muted in southern summer. But rather than getting trapped in speculation I checked global precipitable water at http://www.esrl.noaa.gov/psd/cgi-bin/data/timeseries/timeseries1.pl and its 13% greater in July than in January. So the atmosphere is being wrung dry in southern summer. Incidentally outgoing long wave is 29% greater in July than in January. So, southern summer is a time for enhanced energy storage. Relative humidity is some 4% greater in January than July that tallies with increased cloud cover. Precipitation rate is 9% greater in July than in January reflecting the greater volume of precipitable water at the time of the year when the sun shines mostly over large land masses in the northern hemisphere allowing plants to put out leaves and to respire with gay abandon.

    Regarding the Greenhouse effect and the enhanced greenhouse effect. We differ. My point of view is explained under the heading MORE OBSERVATION: BACK RADIATION FROM THE STRATOSPHERE NOT EVIDENT IN THE TROPOSPHERE in my post https://reality348.wordpress.com/2016/03/26/17-why-is-the-stratosphere-warm/ Empirically downward long wave from a radiating atmosphere simply does not result in increased temperature below the point of radiation. OK its heresy. But look at my explanation and see if you can disagree with what I observe as the stratosphere experiences its annual temperature peak in southern winter. It’s a natural test bench for greenhouse theory.

    If you read this: https://reality348.wordpress.com/2016/02/29/13-the-processes-behind-flux-in-cloud-cover/……Then you will see that we share a lot of common ground. Energy exits the system as long wave infrared and a system that is gaining energy must increase its output at top of atmosphere. In point of fact top of atmosphere radiation globally and near surface air temperature between the equator and 30° south latitude have not increased since 1998. The last three graphs in this post https://reality348.wordpress.com/2016/02/29/13-the-processes-behind-flux-in-cloud-cover/ are material to the argument.

    So, I agree emphatically with your last sentence that reads: Without observing and reasonably QUANTIFING all of the above, TOA to depth of oceans, we are perhaps foolish to say we know.

    Now, a question for you: What are the forces responsible for the whole of year planetary low in surface atmospheric pressure at about 60-70° south that you see here: http://ds.data.jma.go.jp/gmd/jra/jra25_atlas/eng/indexe_surface11.htm

    And thank you for engaging in a discussion. It’s generous of you.

  24. oldbrew says:

    Erl H says: ‘a system that is gaining energy must increase its output at top of atmosphere’

    A report today about a ‘hot Jupiter’ exoplanet which ‘at its closest position receives more than 1,000 times the energy the Earth receives daily from our Sun’, loses its heat from this very close encounter with its Sun in the space of only ten hours.
    http://cbsport.org/2016/03/hd-80606b-weird-gaseous-exoplanet-raises-questions-about/

    Of course if it had oceans things might be different.

  25. David A says:

    Erl, thank you as well for your comments and time. I have been doing some research from your thoughts. Please let me know if I have correctly understood them.

    Erl says…
    =====================
    “The reason for the increase in cloud cover in southern summer is the marked cooling of the atmosphere as the continental landmasses of the northern hemisphere emit much less radiation into the atmosphere than they do in northern summer. So, its simply a function of the temperature of the atmosphere. Reduce the temperature of the air and you get more cloud.”
    =====================
    I agree with this. So even, assuming for now, the same total amount of W/V in the NH summer vs. the SH summer, you would have more clouds in the SH summer, and, in the atmosphere where clouds do not form, dryer air, as the available moisture was condensed to clouds.

    Now the reasons for the cooler air T are many, and I have never seen them quantified. (Which considering the billions of dollars spent on climate research is a travesty, and I think we agree, a missed opportunity to understand climate and disparate feedbacks which the earth demonstrates annually) I maintain the primary causes are;

    … Greater overall planetary albedo in the S.H summer due to increased NH snow cover and ice.

    …Less solar insulation to the atmosphere from the land, as over 19 million less square miles of land are no longer receiving the N.H. summer intense summer solar insolation and quickly conducting and radiating that heat to the atmosphere.

    …Instead an additional 19 plus million square miles of ocean are receiving the more intense SH summer solar energy, yet an undetermined amount of that energy is no longer impacting the atmosphere, but for some time (again, an undetermined time as well) going below the surface into the SH oceans.

    …negative feedbacks, So, despite more intense insolation, the atmosphere cools. The cooling creates more clouds, thus leading to even greater albedo, further atmospheric cooling and reduced surface solar energy.

    I do not know the facts for the amount of total water in the atmosphere, or for each hemisphere, yet it appears rational that 19 plus million square miles of oceans exposed to more intense radiation would lead to increased evaporation from the SH oceans which do warm during the SH summer.

    Does this lead to more clouds, and more negative feedback for the SH summer. I do not know, but it appears logical, and I do not know the lags.

    Erl says;
    ========================================
    The corollary is that a loss of cloud cover in southern summer results in a greater addition to the Earth’s energy budget than if the same amount of cloud cover were lost in June. There is simply more ocean and its more directly under the sun to absorb the extra radiation when cloud is lost in January.”
    “In fact in southern summer much less energy gets back into the atmosphere in the south by comparison with the north allowing cloud cover to be maintained rather than increased as all that potential evaporation doesn’t happen for the lack of a mechanism to convert energy into atmospheric water vapor.”
    ========================================

    Regarding paragraph one, I thought cloud cover increased in the SH summer?

    Regarding paragraph two, what is the S.H. cloud cover in January, in the SH summer, vs. in June, in the S.H.?

    Even if cloud cover is unchanged, the additional solar energy and warmer atmosphere and water would result in more evaporation. It is also logical to me that an addition of 70 watts per sq M insolation, plus more direct and compact solar rays would, at a minimum, initially result in more evaporation. The more direct and intense solar rays would be the mechanism for the increased evaporation.

    Lets discuss rates of evaporation and your good thoughts on transpiration. Corn is a fairly water intensive crop, evaporating about 3,500 gallons per acre into the atmosphere.
    So, looking for rates of salt water evaporation I found this information about San Diego’s Mission bay. I grew up there so selected this…
    Mission Bay San Diego Ca. 14,000 acres with 55,000 acre feet evaporated annually, one acre foot is 325,851 gallons. This equates to 3,500 gallons per acre per day. (annual evaporation is .7921805e10 divided by 365 is 49,100,835.616 divided by 14,000 is 3,507.2 (I think I got this correct)
    (Evaporation From The 17 Western States By J. STUART MEYERS)

    So the same amount of evaporation per acre as Corn. There are, of course, many pluses and minuses to consider. The S.H. has 19,690,500 additional sq. miles of ocean to absorb and evaporate compared to the NH! (At 3,500 gallons per acre per day, that is a lot of water vapor) During the SH summer the solar energy is much more intense for the dual reasons mentioned. (The earth is closer and the rays more dense due to the incident angle) Also evaporation accelerates as water warms. There is additional ocean as SH ice has receded. How much this is counteracted by increased cloud cover and perhaps reduced wind, I do not know.

    OTOH, the NH has, as you mentioned, all that bio growth during the N.H. spring and summer. Yet this is not 100 percent of the 19,690,500 additional sq. miles of land in the N.H. (deserts, high mountains, forrests etc, have little to no growth or seasonal change in evergreens) Also the greater spring and summer bio evaporation is balanced by the greater evaporation rates in NH winter and fall from increased soil moisture evaporating due to more rainfall (See tulee fog in the central valley. I see this for several days in the forest region I live in after heavy rain.)

    Erl, I hope this clarifies my thoughts on this, and any more information you provide is appreciated. Like you, I consider clouds net negative, and CAGW political, not science. Concerning the GHE and CO2, I would not dispute your heresy, (-; and consider your science in this area well above my own understanding. In discussion I tend to leave the physics of CO2 warming to more educated minds, as the observations alone are adequate to refute any catastrophe and reinforce the known benefits. I will look at and think about your atmospheric pressure question.

  26. David A says:

    Regarding my comment question, “Regarding paragraph one, I thought cloud cover increased in the SH summer?”
    ============

    I guess you mean overall cloud cover, but not necessarily SH cloud cover, as the SH land, oceans and atmosphere do warm in the summer, it is likely that SH summer causes reduced SH clouds, even further supporting increased SH evaporation.

    It is curious what would happen if the SH summer orbital mechanical position remained permanent. Would the earth’s atmosphere continue to cool? Would the increased ocean insolation eventually get back to the atmosphere? (Super El Nino’s)

    Does the ratio between ocean SST and near ocean surface air T change seasonally on a global and hemispheric basis?

    I always have more questions then answers, and this annoys the hell out of my wife.

  27. David A says:

    Erl says, “Now, a question for you: What are the forces responsible for the whole of year planetary low in surface atmospheric pressure at about 60-70° south that you see here: http://ds.data.jma.go.jp/gmd/jra/jra25_atlas/eng/indexe_surface11.htm
    ===============================================
    Humm? You can certainly see this aiding the Katabatic winds which are an Antarctic specialty. As to cause, please explain, because I do not understand the ozone affects you discuss.

  28. David A says:

    Concerning S.H. percipitable water…

    Seasonal Variations in the Vertically Integrated Water Vapor Transport Fields over the Southern Hemisphere
    http://r.duckduckgo.com/l/?kh=-1&uddg=http%3A%2F%2Fjournals.ametsoc.org%2Fdoi%2Fabs%2F10.1175%2F1520-0493%25281983%2529111%253C1259%253ASVITVI%253E2.0.CO%253B2

    “Large seasonal differences in precipitable water and in the zonal and meridional fluxes are found, most notably between summer and winter. Summer season, subtropical meridional water vapor fluxes exceed those in winter by a factor of 2. A seasonal asymmetry is noted in the fields of W̄ and Q̄λ in which the autumn magnitudes are larger than those found in spring. A seasonal asymmetry between autumn and spring is also evident in the Q̄ϕ fields but the tendency is for spring to exhibit larger magnitudes than autumn. Strong northward flows of moisture are found west of South America and Africa. Computation of zonally averaged quantities reveals that the moisture content of the Southern Hemisphere atmosphere is greater than that calculated in other works, probably due to high values of the mixing ratios at the 1000 mb level. The zonally averaged meridional flux of moisture is most probably underestimated, possibly by a factor of 2.”

  29. erl happ says:

    David, Yes you have been doing lots of work. That’s great.
    In reply:
    @ “I agree with this. So even, assuming for now, the same total amount of W/V in the NH summer vs. the SH summer, you would have more clouds in the SH summer, and, in the atmosphere where clouds do not form, dryer air, as the available moisture was condensed to clouds.”

    ANSWER Cooling of the air increases its relative humidity. So in that sense its wetter air, some being pushed past its dew point and forming clouds. Cloud cover is greatest in January as the atmosphere cools by 4°C causing increased relative humidity, cloud cover and precipitation.

    We can distinguish between specific and relative humidity. The specific humidity of the air for the globe as a whole is 10% greater in July than in January and the precipitation rate increases by nearly the same amount. For just the northern hemisphere specific humidity is greater by 62% in July than January. For the southern hemisphere its 27% less in July than in January. So, this tells us that the summer is time for increased specific humidity because that gives rise to increased evaporation and leaf transpiration. Much more water and less plants in the southern hemisphere and the increase in specific humidity is much less letting us know the relative importance of plants in humidifying the atmosphere. So much for evaporation from the immense southern oceans.

    We can also look at relative humidity. For the globe as a whole its 3% less in July than in January. For the Northern hemisphere its 2% greater in the last half than the first half of the year. For the southern hemisphere its 6% less in August than in January, a telling statistic. The Southern hemisphere has much drier air in winter when the Mediterranean climates on the west coasts get their rainfall. Its so much drier in these places in the southern hemisphere than comparable climates in the northern hemisphere where relative humidity is so much greater in winter.

    From all this we can see that greater cloud cover in southern hemisphere summer makes a great contribution to reducing the uptake of energy by the southern oceans.Solar radiation is 6% more intense in January than July as we know so that cloud cover has a highly protective function. This will not last forever. Some time in the future the Earth will be closest to the sun in July and it will be a much hotter place when that happens.

    It follows that fluctuations in cloud cover in southern summer are a potent source of variation in the uptake of energy by the bulk of the oceans that exist in the southern hemisphere. That was the point I was making in this sentence: “The corollary is that a loss of cloud cover in southern summer results in a greater addition to the Earth’s energy budget than if the same amount of cloud cover were lost in June”. The point is that there is more ocean in the southern hemisphere to absorb that energy and the intensity of the energy is greater in January when the clouds gather to reflect it.

    Re … “Greater overall planetary albedo in the S.H summer due to increased NH snow cover and ice.” Answer: Increased global albedo in southern summer is due primarily to increased cloud cover following a 4% cooling of the global atmosphere between July and January. I don’t think high latitude snow and ice in the northern hemisphere makes much difference when the sky is full of cloud and the sun is low in the sky.

    In relation to evaporation from plants versus the ocean consider the surface area of the leaves of a tree by comparison with a corn plant. Consider the growing season of corn by comparison with the presence of the tree, all year round pumping water into the atmosphere and the relative number of months where the tree has transpiring leaves. Consider the rate of evaporation from hot soil by comparison with relatively cool water. And consider the statistics provided earlier for specific and relative humidity for the globe and the hemispheres separately. Those stats point towards the importance of plants in humidifying the air, much more important than open bodies of water.

    There is an easy way to answer these very important questions and that is to learn to download reanalysis data from: http://www.esrl.noaa.gov/psd/cgi-bin/data/timeseries/timeseries1.pl

    I demonstrate how to do this and bring it into a spreadsheet here: https://reality348.wordpress.com/2015/12/24/2-assessing-climate-change-in-your-own-habitat/

    Then, you will be able to find the answer to any climate related question that comes into your mind. You will be one of the few people to take advantage of the data that is available on the history of the atmosphere. If you have trouble find me on skype and I will demonstrate.

    Re my question about surface pressure at 60-70° south latitude you are not alone in not having a ready answer. In fact this particular question is never asked. Read this: https://reality348.wordpress.com/2016/01/11/5-the-enigma-of-thecold-corepolar-cyclone/

    Then tell me if it makes sense to you. In that post the mechanism by which climate changes naturally is described. If you understand it, you will one of the few who does. Perhaps just you and me.

    Thank you for the interaction. There is no better way to solve problems than via an uninhibited discussion. Too often internet exchanges on climate are about point scoring and demonstrating ones wit and prowess and that gets us nowhere.

  30. Bob Weber says:

    Erl my view differs from yours in that I see TSI as the driver of evaporation, into colder air yes, but without sufficient TSI, there is little to no evaporation. Case in point, today’s ocean is showing very little evaporation:

    Why? Because TSI has dropped off since early-mid March.

  31. David A says:

    Erl, thanks and will respond when I have a bit more time, after I look at your links, and think! Bob’s comment regarding TSI, is interesting. Yes, 90 percent of the water vapor in the atmosphere does come from the oceans, and the seasonal change is this is a great opportunity to better understand climate. Regarding TSI it is not the change in total TSI in different solar cycles that is as important as the change in W/L. The spectrum change can vary by as much as ten percent or more, and this certainly has ramifications for both the TOA and the ocean heat content. I particularly wish to better understand your TOA links and thoughts.

  32. Paul Vaughan says:

    DA wrote: “the seasonal change is this is a great opportunity to better understand climate”

    Exactly:

    That’s absolutely NON-random.
    It’s absolutely systematic.

    THUS understanding this combination of observations is a TRIVIAL exercise:
    _1_
    __2__
    ___3___
    ____4____

  33. Paul Vaughan says:

    update: “J+N” on graph 1 needs updating based on (φ/Φ)/(J+S)

  34. erl happ says:

    Bob, Re your comment: ‘Erl my view differs from yours in that I see TSI as the driver of evaporation, into colder air yes, but without sufficient TSI, there is little to no evaporation. Case in point, today’s ocean is showing very little evaporation:’

    I will take issue with you on the source of moisture in the air. A lot of moisture that enters the air comes from vegetation on land rather than evaporation from bodies of water. Peak temperature for photosynthesis is in the region of 25°C and most of the globe is on the cool side for maximum productivity. There is a big response to length of day as you can see here: http://images.remss.com/cdr/climate_data_record_browse.html

    Looking at northern summer time the response in atmospheric humidity on the west of the oceans (that happen to be the warmer side) is possibly due to the west to east movement of the air from land to sea. The air over China is very moist.

    That said, photosynthetic activity may increase with TSI. But I would like to see a direct comparison rather than just an assertion.

    In Australia we see more cloud form over dense native vegetation than cropping land, a function of leaf area and the amount of water being recycled into the atmosphere.

    Increased water in the air is associated with convection rather than subsidence. It is the areas where the air subsides that are cloud free. In the latter energy is absorbed by the ocean with little response in terms of evaporation. Convection is associated in particular with the presence of tropical rain forest.

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