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#221 indydave

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Posted 03 February 2016 - 06:15 PM

W:>>This suggests a positive feedback between surface temperatures and cloud development, the opposite to what you require.>>

 

I would think that positive feedback might mean MORE clouds.  What you and Pi need to show is NEGATIVE feedback.  If what is meant by "development" is "how tall they get" I could accept that as being true TODAY.  That is, the warmer the ocean, the more tall/developed the clouds will be.  But that is NOT saying what Pi says, (and what you have sometimes seemed to say) that there would be FEWER clouds when/where the ocean is warmer.  Are you ready to say clearly if you are in agreement with Pi about that?  However, if we try to hypothesize about the post-flood time, rather than TODAY, I would go with what Oard said about how the much more uniformly warmer ocean (post-flood) would not allow for tall development of clouds.  Your quotes from Journal of Climatology in no way address that unique post-flood situation.  At least Oard does try to directly focus on that idea.  And even IF you could show that the clouds were almost all of the cumulonimbus (tall, and "more developed") type, I believe you would agree with me that this would dramatically increase albedo...so all we have left to do is to discuss if the GE would be able to offset all the added albedo.  It would not.  You need about 21x the GE of today (if albedo went up from 30% today to 90%).  Doubling the air temp only increases water vapor to 2.4x.  Where does all the rest come from?  I don't think you've offered any explanation of that yet.

 

I do appreciate that you quoted the paper's equivocal statements...including both those that seem to support you and controvert you.  I will be reading through it and probably comment about it more soon.



#222 indydave

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Posted 03 February 2016 - 08:48 PM

Maybe it's just me, but this statement from that paper (right at the end) sure is confusing.

 

"This decline in MSC and the
warming of the sea surface, taken together with the
negative correlation between MSC and SST, suggests a
positive feedback to warming in regions of persistent
MSC."

 

It sounds to me that it is saying that the more SST (sea temp), the more MSC (low clouds) there will be (i.e. "positive feedback").  But other places in the paper it seems to say the opposite.  It also seems to suggest that there is no GLOBAL correlation.  It is positive in some places...negative in others. 

 

I will paste in other quotes and then highlight (bold) what I think is significant.

 

MSC therefore have a cooling effect
on climate [negative cloud radiative effect (CRE)].
Randall et al. estimated that a 4%increase in MSC cover
could offset a 28–38Cglobal temperature rise.
By contrast,
high (cirriform) clouds are thinner and colder, so their
longwave effect dominates, giving them a positive CRE.

 

WOW!  Did you get that?  It is saying that if you had a 32% increase in low clouds (from 25% today to 57%), you could expect that to be equal to 8 times that amount (8 times 28-32C) of cooling!  That seems like a LOT.  And of course they are (I think) including GE in that. 

 

They found that rising SST acts to destabilize the
marine boundary layer, eventually leading to the entrainment
of dry air
into the cloud deck and the replacement of
stratus cloud with cumulus.
 

It seems to me they are saying the CAUSE of the higher temps converting low level clouds to mid-level clouds is that the rising air pulls in (from the sides) the DRY air.  However in a post-flood state there would not BE any dry air over the very warm ocean!

the greatest cloud cover occurs during the season of highest
LTS. Wood and Hartmann (2006) also found that higher
cloud fractions occurred when LTS was greater.

Oard has said there would be more LTS (stability)...with low amounts of convection...so that the warm/moist air would stay low.  So with more stability then there would indeed be more lower clouds. 

 

Trenberth and Fasullo (2009) examined global climate
models for their changes in the earth’s radiation budget
between 1950 and 2010. The models were those used in
the Fourth Assessment Report of the Intergovernmental
Panel on Climate Change (IPCC). Their assessment
concludes that significant surface warming is expected
due to decreasing global cloud amounts.
Specifically, they
predict a decrease of low and middle clouds in midlatitudes
and a decrease of high clouds near the equator.
 

We were arguing about CAUSATION...which is the cart and which is the horse.  This ("DUE TO")seems to say that less clouds were the cause of the increased warming.  That's what I said. 

 

Total cloud cover appears to be steadily increasing in
Fig. 4a (see below) until 1998 when the time series begins a declining
trend. The same pattern is amplified in low cloud amount
in Fig. 4b.

 

That sure seems to contradict the chart we all were looking at a few pages back (post #140).  The low and high level clouds seem to increase while the mid level decrease....see this chart below.  This was a time of INCREASING global temps.  So that is when the global clouds INCREASED.  I don't know which chart to believe.  This one, or the one in #140 which shows lower clouds decreasing during that time period. 


Attached File  cloudfraction.jpg   53.68KB   0 downloads

A mechanism behind this relationship was hypothesized
by Wyant et al. (1997), whereby an increase in SST
causes a reduction in lower-tropospheric static stability.
The reduced stability allows for more vertical motion
within and around the cloud deck, leading to increased
entrainment of dry air.
This brings about a reduction in
cloudiness and a transition from stratiform to cumuliform
cloud types.
....This relationship was unique between low stratiform and
cumuliform cloud types, suggesting that these two types
tend to trade-off, meaning that in a given year or season
one type is consistently more common at the expense of
the other.


The central Pacific is the only one of the six regions in
which cloud cover correlates positively with SST....It is likely that in this region
convection is driven by SST, and the warmer the sea
surface, the stronger and deeper the convection, leading
to greater and more persistent cloud cover at all
levels.

 

I realize this says only one of 6 regions have positive correlation, however this region is the WARMEST...the central Pacific.  So more warm air there WILL cause more lower level clouds.  In fact it has more of all types except cumulus.  That is the exact region where Pi predicted that we should see FEWER clouds.  Remember when he questioned this pic...if it was in the warmer or colder part of the Pacific?

 

stratuspic.jpg



#223 indydave

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Posted 03 February 2016 - 10:21 PM

BTW, Pi, you have said several times that you will go with what NOAA or NASA say, rather than your teacher's assn (NESTA).  You mocked me by saying the data on a page I PROVIDED to you helped you make your point that higher global temps will cause lower amounts of clouds.  Well, that page (LINK) was not a NASA or NOAA page.  But if you want to use it as an authority over NESTA then you should also note that the same page says THIS: 

 

Water vapour is the single most important greenhouse gas, wherefore it is interesting to note that global warming since 1978 apparently terminated in 1998, simultaneously with the step-like decrease in atmospheric water vapour content. Global climate models forecast an increasing amount of atmospheric water vapour along with global temperature increase.



#224 indydave

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Posted 03 February 2016 - 11:28 PM

It appears that NASA can't make up its mind:  LINK

 

"If the climate should change, then clouds would also change, altering all of the effects listed above. What is important is the sum of all these separate effects, the net radiative cooling or warming effect of all clouds on Earth. For example, if Earth's climate should warm due to the greenhouse effect , the weather patterns and the associated clouds would change; but it is not known whether the resulting cloud changes would diminish the warming (a negative feedback) or enhance the warming (a positive feedback). Moreover, it is not known whether these cloud changes would involve increased or decreased precipitation and water supplies in particular regions. Improving our understanding of the role of clouds in climate is crucial to understanding the effects of global warming.

 

And:  "Moreover, changes in any of these climatic features may also affect the distribution and properties of clouds , but the understanding of clouds is so rudimentary that no one knows whether climate feedbacks involving clouds will dampen or amplify a warming trend. The possibility that clouds might accelerate global warming brings a special urgency to the ancient problem of understanding the climatic importance of clouds."

 

More: "For example, if cloud cover were to increase (as many thought it would, assuming that warmer temperatures would speed evaporation), the amount of sunlight reaching Earth's surface would decrease, but then the thermal radiation trapped by the cloud might increase by the same amount. Even such a simple scenario has problems, though. Because the decrease in solar heating would affect surface temperatures, whereas the change in the emission of thermal radiation would affect air temperatures at higher altitudes, additional cloud cover would reduce the temperature contrasts between the surface and the higher altitudes that drive the winds. Any reduction of winds might in turn inhibit the formation of clouds. The early studies did not account for this possibility.  (Indy: notice, the simpler idea was warmer = more clouds, but some doubted that if there was less wind).  Another idea is that higher atmospheric temperatures could create denser clouds, since greater evaporation rates at higher temperatures would make more water vapor available in the atmosphere for cloud condensation. Because denser clouds reflect more sunlight, there would be an enhanced cooling effect. (Indy: note that it was not a question of if more clouds form if it is warmer) This would reduce the magnitude of the greenhouse warming. On the other hand, denser clouds might also lead to an increase in precipitation (rainfall and snowfall), possibly from storm clouds, whose tops are especially high and cold. Such clouds, which are particularly good absorbers of thermal radiation, could more than make up for their tendency to block sunshine. In that case the warming would be intensified. (Indy: so again it is not a question whether warmer = more clouds...it is just about if the GE warming will offset the cooling). 

 

And: "The cloudiest regions are tropics   (Indy: this surely seems to contradict what both Pi and Wibble have said). And the temperate midlatitude storm zones; the subtropics and the polar regions have 10-20% less cloud cover....High-latitude clouds are almost twice as reflective as most clouds at lower latitudes.  (Indy: so I guess there are less of them but they are more reflective...so maybe that's why the maps are brighter white at the poles while MORE clouds are at the equator)....Meteorologists have long associated greater cloud cover, higher cloud tops and denser, more reflective clouds with regions of more vigorous storms. Both the tropics and the low-pressure areas at midlatitudes are regions of severe weather."

 

Also:

 

"The process traps heat like a blanket and slows the rate at which the surface can cool by radiation. The blanketing effect warms Earth's surface by some 7°C (13°F)."

 

To me, this suggests that if you tripled the lower level clouds from about 28% now to 84%...that would cause a 21C warming effect.  However, if you triple the albedo to 84%, then you get 90C worth of cooling (acc. to the albedo calc site).  Subtracting the two gives you a net 69C of cooling.  If you doubled, then there would be 14C of warming to offset 33C of cooling...for a net temp change of -19.  Or a global avg temp of -4C.  That's pretty close to the 0C figure I suggested during the ice age. The quote from this NASA page surely supports my idea. 

 

OK Pi...I've supplied quotes from NASA's International Satellite Cloud Climatology Project (ISCCP) which show that warmer oceans cause more clouds.  Or at the least, they can't make up their mind about it.  Now it's your turn to show quotes from them saying warmer oceans cause FEWER clouds.  Go right ahead. 

 

OR...you can admit you are wrong. 



#225 indydave

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Posted 03 February 2016 - 11:45 PM

I saw this:

LINK

"A mean temperature rise of just 0.1 degrees Celsius in oceans corresponds to a temperature increase of 100 degrees Celsius in the atmosphere if all the heat associated with the ocean anomaly was transferred into the atmosphere."

 

This says to me that if you lost 1C from the ocean in one year, then it would heat up the atm by 1000C.  Or if you lost .001C from the ocean, it would raise the atm by 1C.  So if you lost (say) 15C from the ocean in 700 years (to cool it from 30C to 15C) that means that you would be supplying .021C per year from the ocean to heat the atm.  If you multiply that by 1000 that gives you 21C per year of heat from the ocean added to the atm to replace whatever is lost due to increased albedo (lost solar influx).  Acc to the albedo site, an albedo of 47 would exactly equal 21C of cooling.  If you had (say) an addition 10C of cooling, that could be enough to cause an ice age.  Maybe even just 7C or so would. (That's what I think we are told was the coldest temp.)  An albedo of 55 would give you that extra 10C of cooling. 

 

I was thinking of trying that calc myself, to figure the mass of the ocean vs. the atm and the specific heat of water vs. air, but finding this quote (if it's right) saved me a lot of effort!



#226 indydave

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Posted 04 February 2016 - 11:23 AM

Pi>>Both statements were supported by an explanation from NOAA showing the development of such storms takes place over warm waters when converging air masses collide. Oard's model is based on LOTS of warm water. IIRC, you have pretty much acknowledged Oard probably wouldn't argue too much about the increase and severity of tropical storms.<

No, he has said and I have posted here that he would say that with a warmer ocean there would be few taller clouds and more low clouds.

>> 1) I didn't say a warmer ocean will cause clear skies, just fewer clouds. <

Really? You want to quibble over my not saying clearER instead of clear? Everyone knew I wasn't talking about perfectly clear sky including you. But I guess that's your best argument in defense of your having spoken out of both sides of your mouth on this. How can you have more storms without more clouds?

>1) Clouds and water vapor are competing feedback loops.
2) Predicting the net influences of them is one of the big problems of climate prediction.
3) One loop is a positive feedback due to increased water vapor.
4) The other loop is a negative feedback due to increased cloud cover.
5) Scientists don't know which of these will dominate.<<

Yes of course sometimes they will admit to this not being clear. Other times they speak as if they know for sure there could be catastrophic warming. But what is under no dispute by them is whether warmer temperatures will cause more clouds. At least not in this quote from NESTA. Their question was about whether the increased clouds would cause enough warming to offset all the cooling.

>>or that they aren't relevant to the point we're (still) working on.... the increased cloud-cover that seems to be a requirement of Oard's model.<<

No, increased clouds to cause cooling is definitely NOT any requirement at all for his model. I have suggested increased clouds could also play a part in causing greater albedo and cooling. Not Oard.

#227 indydave

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Posted 04 February 2016 - 12:43 PM

I wrote:

Maybe it's just me, but this statement from that paper (right at the end) sure is confusing.

"This decline in MSC and the
warming of the sea surface, taken together with the
negative correlation between MSC and SST, suggests a
positive feedback to warming in regions of persistent
MSC."

It sounds to me that it is saying that the more SST (sea temp), the more MSC (low clouds) there will be (i.e. "positive feedback"). But other places in the paper it seems to say the opposite.
===

Ok, I can see now that the idea of positive feedback the paper spoke of was between clouds and warming. At the same time it spoke of a negative feedback or negative correlation between warm oceans and clouds. I think it is legitimately confusing however I guess it could mean that the warm oceans cause fewer low level clouds and then the fewer clouds will allow more solar radiation in and that will cause warming.

I still think that paper is equivocal.

#228 wibble

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Posted 06 February 2016 - 04:40 PM

First I want to point out something in your reply to Piasan
 

And: "The cloudiest regions are tropics (Indy: this surely seems to contradict what both Pi and Wibble have said). And the temperate midlatitude storm zones; the subtropics and the polar regions have 10-20% less cloud cover....


This is the original quote:

"The cloudiest regions are tropics and the temperate midlatitude storm zones; the subtropics and the polar regions have 10-20% less cloud cover."

Why did you split the sentence to make it look like it was saying that the tropics are cloudier than the temperate mid latitude storm zones ?
 

W:>>This suggests a positive feedback between surface temperatures and cloud development, the opposite to what you require.>>

I would think that positive feedback might mean MORE clouds. What you and Pi need to show is NEGATIVE feedback. If what is meant by "development" is "how tall they get" I could accept that as being true TODAY. That is, the warmer the ocean, the more tall/developed the clouds will be.


Yes taller clouds not more surface covered. So you accept that as true today, good.
 

But that is NOT saying what Pi says, (and what you have sometimes seemed to say) that there would be FEWER clouds when/where the ocean is warmer.


I think Piasan has expressed uncertainty, which is the correct thing. Warmer air can hold more moisture and therefore could potentially produce more cloud. On the other hand warmer air is able to hold more moisture without it condensing.
 

However, if we try to hypothesize about the post-flood time, rather than TODAY, I would go with what Oard said about how the much more uniformly warmer ocean (post-flood) would not allow for tall development of clouds.

uragan-system.jpg

The storm clouds produce their own cool, dry air from the top of the system. It's an engine working off the heat of the ocean to produce wind and rain. Doesn't matter how uniformly warm the ocean is.


And even IF you could show that the clouds were almost all of the cumulonimbus (tall, and "more developed") type, I believe you would agree with me that this would dramatically increase albedo...so all we have left to do is to discuss if the GE would be able to offset all the added albedo.


You’ve learnt since the early stages of this thread that tall clouds (like cumulonimbus) have a neutral effect on temperature. How have you now forgotten that ?

Besides, stratus already has a high albedo (although interestingly the Eastman paper states that it is only 40-50 %). Replacing that with cumulus type, as the paper indicates would happen as cooler ocean areas warm, would promote heating (neutral clouds plus more gaps in those clouds letting sunlight through)
 

MSC therefore have a cooling effect on climate [negative cloud radiative effect (CRE)]. Randall et al. estimated that a 4%increase in MSC cover could offset a 28–38Cglobal temperature rise.

WOW! Did you get that? It is saying that if you had a 32% increase in low clouds (from 25% today to 57%), you could expect that to be equal to 8 times that amount (8 times 28-32C) of cooling! That seems like a LOT.


Yes it is a lot if you completely change what was said in the paper. Here’s what it says:

Randall et al. (1984) estimated that a 4% increase in MSC cover could offset a 2-3°C global temperature rise.

I don’t understand how you’ve done that ?
 

It seems to me they are saying the CAUSE of the higher temps converting low level clouds to mid-level clouds is that the rising air pulls in (from the sides) the DRY air. However in a post-flood state there would not BE any dry air over the very warm ocean!


Oard has said there would be more LTS (stability)...with low amounts of convection...so that the warm/moist air would stay low. So with more stability then there would indeed be more lower clouds.


I refer you again to the chart earlier. If Oard really thinks that tall clouds can’t form over a warm oceans then he’s talking rubbish. No other meteorologist would say that.
 

“The central Pacific is the only one of the six regions in which cloud cover correlates positively with SST....It is likely that in this region convection is driven by SST, and the warmer the sea surface, the stronger and deeper the convection, leading to greater and more persistent cloud cover at all levels.”

I realize this says only one of 6 regions have positive correlation, however this region is the WARMEST...the central Pacific. So more warm air there WILL cause more lower level clouds.


It says cloud at all levels. Not just low clouds. So insignificant net feedback due to clouds on temperature.
 

"The process traps heat like a blanket and slows the rate at which the surface can cool by radiation. The blanketing effect warms Earth's surface by some 7°C (13°F)."

To me, this suggests that if you tripled the lower level clouds from about 28% now to 84%...that would cause a 21C warming effect.However, if you triple the albedo to 84%, then you get 90C worth of cooling (acc. to the albedo calc site). Subtracting the two gives you a net 69C of cooling. If you doubled, then there would be 14C of warming to offset 33C of cooling...for a net temp change of -19. Or a global avg temp of -4C. That's pretty close to the 0C figure I suggested during the ice age.


Cloud does not supply the entire albedo of the planet, Deserts for example have an albedo of 0.3, any surface will have some albedo. The average albedo of Earth is 0.31. So how is tripling clouds from 28% going to triple the total albedo ?

Also, talk of 90C cooling due to cloud albedo is nonsensical. The Earth would be 12C warmer if there were no clouds (net effect incl. GE is 5C cooling at the surface). So the albedo effect of current cloud cover of 60% allows for 12C cooling. Forgetting GE that suggests that 100% cover gives 100/60 x 12 = 20C

But none of that matters anyway because you still haven’t shown why low clouds would drastically increase and cirrus disappear in your hot ocean scenario. All the observational data that has been presented in this thread and the content of the Journal of Climatology paper shows that there is no justification for that idea (and that paper is no way equivocal as you bizarrely state).

You promised in post #210 that you would demonstrate how hot oceans produce your low cloud/no high cloud scenario....



#229 indydave

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Posted 09 February 2016 - 08:04 AM

I said I would demonstrate when you have demonstrated, and you demonstrated nothing. All you did was give your hypothetical reasoning for why you think something about the Gulfstream from the past. And I gave my reasoning as well. How does anyone demonstrate anything from the past?

#230 indydave

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Posted 09 February 2016 - 08:11 AM

Maybe it would help a lot if you would demonstrate why it is that if just one large volcano can drop global temperatures for 2 years by 1C or even 5C as we are told about one from 75000 years ago, why would it be that having 100 or 1000 volcanoes would NOT drop temperatures significantly for a long enough time to launch an ice age? Explain that. No...DEMONSTRATE that.

#231 indydave

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Posted 09 February 2016 - 08:14 AM

Also while we're on this subject, is it your opinion that all of the assumptions of evolution and ancient earth have been DEMONSTRATED?

Or do you think maybe you should have used a different word?

#232 indydave

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Posted 09 February 2016 - 11:36 AM

W>Why did you split the sentence to make it look like it was saying that the tropics are cloudier than the temperate mid latitude storm zones ?>>

I'm not sure why that happened. It was not intentional. I congratulate you for catching that, but I can't imagine why you would think I was making some point that way. I put bold face on the part I thought was significant.  Now let me ask YOU, why did you not reply to the very obvious point that this page supports... my view that a warmer ocean (i.e. the tropics) indeed DOES have more cloud cover AND that the polar regions have LESS?  Why major in minors?  Why have you decided to tithe mint and left the weightier matters undone? This contradicts what both you and Pi have argued.  Why just whiff right over that point?   You might have done well to have paid attention to that part of it, rather than wasting time studying about monsoons, or imagining that I was up to something nefarious by an accidental change of punctuation after I inserted my comment in parentheses. So will you admit that this quote does indeed refute what you and he were saying...that warmer water makes less clouds...or that there are more clouds over the polar areas?  (And DON'T pretend it was only PI saying it!...or that he only "expressed uncertainty"!)

>The storm clouds produce their own cool, dry air from the top of the system. It's an engine working off the heat of the ocean to produce wind and rain. Doesn't matter how uniformly warm the ocean is.<<<

If this were true then one might think there would only be taller clouds in the tropics today...or ANYWHERE where there is a body of water warmer than the air over it. I will rely on what Oard said, and also on the point I have made several times...that in order to have a net warming from GE then there must be a cooler surface below. This means that with normal surface temperatures that we have today there is longwave radiation warming from clouds which would not happen with a very warm ocean just after the flood.

>>You’ve learnt since the early stages of this thread that tall clouds (like cumulonimbus) have a neutral effect on temperature. How have you now forgotten that ?<<

And I hope you have known since BEFORE you started this thread that volcanoes cause significant global cooling. Yet you began this thread on the premise that Oard had to be WRONG about that!  When will YOU admit to that error???  Are you wrong to say that volcanoes cannot cause substantial global cooling???  The warm parts of the ocean today are definitely not filled with only cumulonimbus clouds...the tall type...as your argument implies.  Lower level clouds predominate.  Not every ocean cloud is a hurricane, which is what the image you used is.  So your idea that clouds produce their own cool dry air which always cause taller clouds when the ocean is warm is bogus.  And I did use "always", because you have suggested that your visual of the cloud "engines" applies to all clouds.  It does NOT. 

 

THIS page, describes two types of convective rising of air...one is stable, and the other unstable.  (The unstable is the type that makes taller "deep convective" clouds...like you showed.)  Both are a result of warm/moist air rising, but it is the environmental factors that makes them different. 

 

"Convection is controlled by atmospheric stability. It can be forced initially by the warming of air parcels near the surface, but the vertical profile of temperature determines whether convection will be deep (that is penetrating to high elevation as in Fig 3) or shallow as in Fig 2."  and  "If vertically displaced parcels sink back to their initial elevation after the lifting ceases, the environment is stable."

 

Dry Parcel Rising in Warm Environment

 

Lec2Fig1dry.GIF

 

 

"If, on the other hand, we are faced with the situation shown in Fig 3 the consequences of an initial "lift" are quite different. The environmental lapse rate is 10 °C/km - higher than the adiabatic lapse rate - and the parcel continues to rise throughout the entire column."

 

Dry Parcel Rising in Cold Environment

 

Lec2Fig2dry.GIF

 

(BTW, the term "dry parcel of air" can't mean no moisture in it. The dry lapse rate is always constant...at 9.8° C/km.  The parcel must have moisture for it to not have a lapse rate equal to 9.8 °C/km. Or maybe it is dry in the sense that it already has the moisture condensed out to form a cloud, but it still rises. I don't think it means "no clouds".)

 

I believe the conditions after the flood would be more like the former...where the temp changes with altitude ("environmental lapse rate") are LESS than the adiabatic lapse rate.  The ocean would cause a thicker and warmer cloud environment.  And Oard agree with me.  The picture Wibble showed is of the latter condition...a colder air environment, which makes deep convective clouds. 

 

BTW, I would like for Wibble to provide the source for the image he showed...so I can read what it has to say.

 

>>Yes it is a lot if you completely change what was said in the paper. Here’s what it says:

Randall et al. (1984) estimated that a 4% increase in MSC cover could offset a 2-3°C global temperature rise.

I don’t understand how you’ve done that ?<<

 

 

I don't either.  I surely wouldn't have intentionally changed that to make it a ridiculous number.  If I were trying to pull a fast one, I'd use something more reasonable, and hope you wouldn't check it.  This INVITES you to check it.  I did notice weird stuff happening when I tried to cut/paste...I kept getting a "snapshot" (picture) rather than copying of text.  So, the point is even more valid since it is not a ridiculous number.  (My "that seems like a LOT"...proves I was doubtful of it, rather than lying about it).  If indeed the cloud cover for low-level clouds went up from 25% today to just 45% (i.e. increases 5 x 4 = 20%)...that means a 10-15C global temp decrease is indeed possible, INCLUDING GE.  Since land albedo and volcanic albedo would be added, then that makes it even a greater amount of cooling.  This paper you cited helps to support my contention.  The point is stronger after the correction.  So...what ELSE can you say in reply to it?  You can COUNT on me repeating this point over and over until you answer it. 

 

>>I refer you again to the chart earlier. If Oard really thinks that tall clouds can’t form over a warm oceans then he’s talking rubbish. No other meteorologist would say that.>>

Oard would laugh at you.  He understands what you don't...(and I'll admit I didn't either)...that tall clouds are formed when the rising air is UNSTABLE.  That is, its cooling rate (lapse rate) is greater than 9.8 °C/km.  Sometimes it is, sometimes it isn't, depending on the environmental conditions.  Even today, the tall type of clouds do NOT predominate over warm oceans.  And even if they DID after the flood, then the GE would not be downward toward a warmer surface.  It would go upward. 

 

>>It says cloud at all levels. Not just low clouds. So insignificant net feedback due to clouds on temperature.>>

Yeah, but you and Pi were trying to affirm that TOTAL CLOUD COVER WOULD BE LESS...where the ocean is warmest.  That is the FIRST part of it...there IS positive feedback of warm water on cloud fraction for the LOW type (MSC).  There was also the SECOND part...a negative feedback where if you have fewer clouds then the ocean is heated more.  (To me this implies when you combine the two, there is in totality a negative feedback loop...a self-adjustment, which God designed to keep our planet from overheating).  I showed you to be wrong about warmer parts of the globe having fewer clouds. Here is the relevant quote:

 

Colder ocean water is
associated with increased low cloud amount in regions of
persistent MSC, such as off of the southwest coast of
North America, the west coast of South America, the
southwest coast of Africa, the coast of southern Europe,
and the west coast of Australia. Low clouds correlate
positively with SST over regions of warm SST, as is shown
by the patches of positive correlations over the Indian
Ocean, the central Pacific, the western Pacific warmpool,
and the Caribbean.

 

If you want to argue a DIFFERENT point (that more cloud cover won't mean more cooling) then the gracious thing to do would be to FIRST admit your error about THIS point, before "moving on", hoping no one notices you were wrong.

 

>>Cloud does not supply the entire albedo of the planet>>

Of course not.  Land supplies 15% of the 30% we have now.  At least that's one number I've seen.  It might be less than that.   

 

>>So how is tripling clouds from 28% going to triple the total albedo ?>>

You have made a fair point.  I will try to adjust what I said.  If the cloud "blanket" is quadrupled from 15% to 60% that would cause (7 x 4) 28C in warming.  If we have 4x the cloud albedo and 1x the land albedo, that is 75% total.  And the albedo site says with 75% albedo, there would be 66C in cooling...offset by that 28C in warming.  Hardly a solution for you...to have global temps drop by "only" 38C, including GE.  So now, that I have fixed my mistake...what is your answer?  Oh, and I'm being generous here, because I think it is very reasonable that if you combine cloud and volcanic albedo post-flood, that the albedo of the planet would be GREATER than 75% for a while. 

 

>>Also, talk of 90C cooling due to cloud albedo is nonsensical. The Earth would be 12C warmer if there were no clouds (net effect incl. GE is 5C cooling at the surface). So the albedo effect of current cloud cover of 60% allows for 12C cooling. Forgetting GE that suggests that 100% cover gives 100/60 x 12 = 20C>>

I just took a quote from the paper YOU cited, and then applied it, using the albedo site.  I got 38C of cooling this time.  I could reduce that a LOT to be generous and still have the 7C to 10C that I think would cause an ice age.  And that doesn't even COUNT volcanic albedo.  I believe Oard's figure is 5C of cooling (just from volcanoes), but I'm not sure.  He says the winters would be WARMER than ours today.  It would be the considerably cooler SUMMERS that he'd say brought on the ice age.

 

>>But none of that matters anyway because you still haven’t shown why low clouds would drastically increase and cirrus disappear in your hot ocean scenario.>>

When I say "disappear", I mean "underlain by lower and more reflective clouds."  Not necessarily that they go away totally.  I am not sure if there are cirrus clouds over lower clouds today...but I believe there are.  In fact I'm quite sure they are because I recall seeing high and low clouds when I was on a plane in between the two types.  So you could have the exact same amount of cirrus I suppose but instead of having ocean or land below them, they would have lower level clouds. 

 

>>All the observational data that has been presented in this thread and the content of the Journal of Climatology paper shows that there is no justification for that idea (and that paper is no way equivocal as you bizarrely state).>>

That paper and other sources are indeed unclear about whether warmer ocean temps cause more or fewer clouds.  There is ZERO doubt that there would be much more vapor placed into the air and if it rises then it would condense (so long as there are aerosols for the water to condense around...and there would be more of those post-flood).  You have to hang your hat on the false idea that the vast majority of additional clouds would be deep convective clouds (with tons more precip...which you DON'T want) which are not warming but only NEUTRAL and that is only IF the surface is cooler than the cloud such as what we have today.  Remember...heat moves toward the cooler place, not the warmer one!



#233 indydave

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Posted 09 February 2016 - 04:26 PM

I tried to do an edit of the prior post...but I guess my time to edit ran out.

 

>>So your idea that clouds produce their own cool dry air which always cause taller clouds when the ocean is warm is bogus.  And I did use "always", because you have suggested that your visual of the cloud "engines" applies to all clouds.  It does NOT.>>

 

I should have used "all CONVECTIVE clouds" (or some other wording maybe...not sure what)...since I think Wibble would not apply his visual to clouds such as cirrus or fog or altostratus, etc.  But I do believe he implied that when speaking of warm air rising to produce clouds, he would say that the cloud can sort of self-actuate and supply what is needed to cause it to build into the taller types.  I don't think that is right. 

 

I also want to edit this:

 

>>If the cloud "blanket" is quadrupled from 15% to 60% that would cause (7 x 4) 28C in warming.  If we have 4x the cloud albedo and 1x the land albedo, that is 75% total.  And the albedo site says with 75% albedo, there would be 66C in cooling...offset by that 28C in warming.>>

 

I made two mistakes.  One is I should not have used 4x.  The other is that I double counted one GE by using a "1" on the site, and then also using it again when I figured how much the 7C of warming would be to offset the cooling.  In other words if I want to figure the effect of tripling and use 3x7C, then I need to have a zero entered at the site...or I could use 2x7 and have a one at the site.  I will go with the former. 
 

Instead of 4x (which makes total low level clouds to go up from 25% now to 100%), then 3x is probably better.  That means 3 x 7 or 21C in warming which offsets (3 x 15 + 15 = 60) 60% albedo or 60C in cooling...for a net cooling of 39C.  Using 2x, you get 14C warming to offset 45% albedo or 42C of cooling, which results in net cooling of 28C.  None of this includes the volcanic albedo increase...or additional land albedo from snow that does not melt in summer. 

 

I did this correction quickly so maybe I got something wrong...I'm sure one of you will let me know.  Has anyone else noticed that they have shortened how long we have to do edits?



#234 indydave

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Posted 10 February 2016 - 06:35 AM

Me:>>I did this correction quickly so maybe I got something wrong<<

I think now that if cloud albedo is increased to 75%, then that would have to reduce land albedo. Perhaps changing it from 15% to maybe 5% would be better, but I'm not going to redo it right now.

#235 wibble

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Posted 10 February 2016 - 04:58 PM

There are multiple false statements in your post #232 (for example, your allegation that I don't think volcanic eruptions have a cooling effect on the climate is false), I haven't the time to go through them all now though, so I'll just comment on the following:
 

THIS page, describes two types of convective rising of air...one is stable, and the other unstable.  (The unstable is the type that makes taller "deep convective" clouds...like you showed.)  Both are a result of warm/moist air rising, but it is the environmental factors that makes them different. 
 
"Convection is controlled by atmospheric stability. It can be forced initially by the warming of air parcels near the surface, but the vertical profile of temperature determines whether convection will be deep (that is penetrating to high elevation as in Fig 3) or shallow as in Fig 2."  and  "If vertically displaced parcels sink back to their initial elevation after the lifting ceases, the environment is stable."


Dry Parcel Rising in Warm Environment

 

Lec2Fig1dry.GIF

 
 
"If, on the other hand, we are faced with the situation shown in Fig 3 the consequences of an initial "lift" are quite different. The environmental lapse rate is 10 °C/km - higher than the adiabatic lapse rate - and the parcel continues to rise throughout the entire column."
 

Dry Parcel Rising in Cold Environment

 

Lec2Fig2dry.GIF

 
(BTW, the term "dry parcel of air" can't mean no moisture in it. The dry lapse rate is always constant...at 9.8° C/km.  The parcel must have moisture for it to not have a lapse rate equal to 9.8 °C/km. Or maybe it is dry in the sense that it already has the moisture condensed out to form a cloud, but it still rises. I don't think it means "no clouds".)
 
I believe the conditions after the flood would be more like the former...where the temp changes with altitude ("environmental lapse rate") are LESS than the adiabatic lapse rate.  The ocean would cause a thicker and warmer cloud environment.  And Oard agree with me.  The picture Wibble showed is of the latter condition...a colder air environment, which makes deep convective clouds.

 


First, to hopefully clarify as you seem unsure - the dry lapse rate is constant as you say but the ascending air parcel won't form clouds until the dewpoint is reached. Once that happens, latent heat is released (therefore slowing the decrease in temp of the air parcel with height) and the parcel of air rises at the wet adiabatic lapse rate, and will continue to do so until it falls below the temperature of the ambient air.

Secondly, why do you think the first graphic fits your post Flood world ? Your whole argument rests on a hot ocean and a cold atmosphere. Surely the second graphic would be the scenario - the hot ocean would heat up air (with high water vapour content) close to the surface, parcels of air would rise and will keep going upward as it moved up through the cold air. As it expands and cools water vapour condenses, releasing latent heat promoting continued convection. Exactly the recipe for very tall cumulonimbus clouds.



#236 indydave

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Posted 11 February 2016 - 12:19 PM

W:>>Secondly, why do you think the first graphic fits your post Flood world ? Your whole argument rests on a hot ocean and a cold atmosphere.>>

 

I guess you feel it cannot be both...a cooler global temp AND stability due to air temps falling at or below 9.8C/km.  I don't agree, and I guess neither does Oard.  The very warm ocean would likely cause the RATE of drop in temp to be slow, although the total solar heat reaching the ground would be less.  I don't think you can equate rate of drop in atm temp with what the surface temp of the planet is. 

 

>>As it expands and cools water vapour condenses, releasing latent heat promoting continued convection.>>

Seems to me that this is a recipe for a LOW rate of drop in temp...since heat is added to the atm from the ocean when it condenses.  So maybe you should clarify, if lots of heat from the ocean is put into the atm, why would that make the drop (rate...degrees C per km) in temp be MORE, rather than LESS. 

 

>>your allegation that I don't think volcanic eruptions have a cooling effect on the climate is false>>

Then why would you not admit to there likely being much cooling in either Oard's or Brown's model, since both involve increased volcanism?  You can DENY that there were more volcanoes I suppose, but if you allow that there WERE more, then it would follow that there would be much cooling...just as Oard said BUT you challenged in your first post.  I suppose we have wasted 12 pages here because of your lack of clarity.  I think you should have ONLY focused your attack on if there WERE increased volcanism, rather than questioning the cooling effect of an increase.  As I have said, even if there were not added albedo due to increased clouds, then ONGOING volcanism and the idea of SO2 (not ash) causing the drop in solar influx, would have sufficiently answered your first post. 



#237 indydave

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Posted 11 February 2016 - 03:48 PM

I want to clarify what I wrote:

 

>>Seems to me that this is a recipe for a LOW rate of drop in temp...since heat is added to the atm from the ocean when it condenses.  So maybe you should clarify, if lots of heat from the ocean is put into the atm, why would that make the drop (rate...degrees C per km) in temp be MORE, rather than LESS.>>

If I read correctly it is not the cooling rate of the PARCEL that determines if deep convection happens, but rather the rate of cooling of the SURROUNDING AIR or the "environment".  So if the environment is warm and SLOWLY cools with altitude then that is the shallow convection situation.  To me, this means that if there were thick clouds where they radiated the ocean's heat back and forth within the cloud itself, except at the top where it would radiate upward, and if there were latent heat released due to condensation, then this describes an environment where the cloud stays warmer longer (altitude, not time), so the environmental lapse rate would be LOW...not HIGH, and HIGH would be needed to cause instability and get tall deep convection clouds.  And another point...you could have two clouds which might actually be the same thickness or height with one having substantial GE (because of large droplets) but another cloud which is just as tall (but is just THICK, and not "deep convection") may have very low GE because of the smaller droplets. The latter would be what is expected with the warm ocean post-flood situation. 

 

I don't see this as all that important, because the GE of even a very tall cloud would not be similar to the GE of that type of cloud today IF the surface below is warmer than the cloud.  Heat moves toward a cooler place...and that would be UP. 



#238 piasan

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Posted 14 February 2016 - 04:16 AM

Pi>>Actually, I had no position on the matter until you produced that chart showing warmer temperatures = less cloud cover.  I thought about that a bit, and it made sense to me.>>

 

Then I am quite sure I won't convince you that having a warmer ocean would produce more clouds...of ANY type.  Nor could Oard convince you that having more clouds would cause more precip...which seems patently obvious.  Oard would say that all the cooling (in summers) would be due to prolonged volcanic aerosols causing an increase in albedo...at least to "kick off" the ice age.  I am of the opinion that clouds would also increase albedo but apparently he didn't see that.  He didn't DISagree with my point, but his brief email to me didn't say "yeah, that's a good point."  It might just be a bit of his ego, not liking a novice stepping on his turf, but maybe he would agree with your belief that there would not be more cloud cover...at least not over the oceans...so as to add to albedo.  It appears from your latest posts that you have sort of conflated what I have said with what Oard says.  He shouldn't be connected to my view about the clouds. 

Again, it was only AFTER you produced multiple data sets showing an inverse relationship between surface temperature and cloud cover that I accepted the data and formed a conclusion.  That conclusion is fairly "soft" in that I don't have a really great stake in it.  Recall, my initial position on the matter of increased cloud cover was uncertainty.

 

What I have said, and am absolutely firm on, is that sea surface temperatures of 30oC proposed by Oard will lead to highly convective clouds (ie: thunderstorms) and a major increase in both the number and intensity of tropical storms (ie: hurricanes / typhoons).  Further, those storms will reach to much higher latitudes than today.

 

If Oard says the cooling is due to volcanic activity, why have we spent 200+ posts arguing your claims rather than his?

 

You should remember, that Wibble has not so far taken your view that clouds would DECREASE with warmer oceans.  He just disputes that there would be much cooling since he thinks there would be more of the taller type...which our source (NASA site) says TODAY involves a neutral cooling/warming due to GE.  My point would be that there would not be nec. more of that type and if you DID but had a warm ocean under them, the direction of the longwave radiative warming would go UP. 

It isn't really all that important to me whether clouds increase or decrease.  The important issue is the net effect of clouds.  It seems just about everyone says there are a lot of interacting variables with respect to the impact of cloud cover and they just don't know how it will play out.

 

 

That is not resolvable by much more interchanges, IMO.  And if you think much warmer oceans would involve CLEARER skies (with less clouds to cause more snow?) then I don't see that being resolved either.  I have given my opinion (which agrees with your Science Teachers Assn, BTW...see below) and you have given yours. 

Oh, I fully agree with what the science teacher staff writer said.  All of it.  You are the one who is reading between the lines and impeaching the source by suggesting ulterior motives when they disagree with you.

 

If you want my "opinion" on what warmer temperatures can do, I can give it to you from some 25+ years of living in a sub-tropical climate (Florida).  In the warmest parts of summer, we could count on a thunderstorm at 10AM, 1PM, 4PM, 7PM, and sometimes 10PM.  These are highly vertical (convective) systems forming almost like clockwork every three hours or so.  One time I watched a small puffy (low level) cloud develop into a full blown thunderstorm; drop two waterspouts; and dissipate to a high wispy remnant in 45 minutes.

 

For my "opinion" on the impact of the tropical-type storms that will form over warmer oceans... we got 14 inches of rain in one day last spring from the remains of such a storm as it rained out over land.  So, yes, they will move a lot of water.  The real question is how much of that water will be in the form of snow.

 

>>You have no idea what part of the Pacific is covered by that picture.  OK, it's evidence of what?  You have no clue if that's the Gulf of Alaska or the Marianas Islands.>>

 

I will grant you...the caption doesn't say what part of the Pacific it was.  I SAID that.  AND I would bet that if it DID say "near Hawaii" you would have still said that doesn't affect your view at all.  So before I go hunting another pic with similar clouds over the lower latitudes...WOULD IT affect your view??? 

Yes, you did say you didn't know what part of the Pacific was covered by the picture.  So what was the point?  It does have some interesting features.  That said, I could produce a few hundred pictures of hurricanes and typhoons that have seen form over warm oceans  Probably even a dozen or so time lapse videos.  Would that affect your view?

 

>>Again, on this topic, I'm restricting my comments to their relationship with Oard's claims.  For that reason, I'm only discussing the relationship between surface temperature and cloud cover ... which is relevant. >>

None of this applies to Oard's view.  His view is that volcanoes caused higher albedo.  If the skies were clearer of clouds over the ocean...but then had plenty of moisture to cause big snows over land...and if the summers were cooler, that is what fits his view.  It all COULD have been from increased SO2.  I didn't understand that at the time I first replied to Wibble here.  If someone who is very knowledgeable about this (and it can't be a HS science teacher, because the Assn would not agree with what Pi has said!) tells me there would be FEWER clouds if the oceans were much warmer, then I would desist with my arg.  I would then probably say that Oard's view is still a good one since the albedo WOULD be substantially increased by volcanoes after the flood...cooling the planet...and they would likely persist for quite a while.  The conventional idea of ice ages surely doesn't have as much rational appeal.  Do you agree Pi that more volcanoes could trigger an ice age?...or at least substantial cooling? 

Oh, I fully agree with what the teacher's association, NASA, and NOAA say on the matter.  The number of variables associated with the feedback of cloud cover makes it too complex to predict.  Without going into more specifics and because this is getting really d --- r --- a -- w --- n out....

 

Dave asks for a citation from NASA on the matter of the effects of cloud cover.  Some of the graphs we he produced came from the Goddard Institute.  Goddard is a branch of NASA.

 

Since we need to get back to Oard's proposal, I plan on only one more post discussing the matter of clouds then will switch to volcanos as suggested by Oard and requested by Dave.....

 

None of this applies much at all to what Oard has written.  He could agree it would be stormy (tall clouds) over much of the ocean. 

Good.  I doubt you'd find any meteorologist (including Oard) who would argue global ocean temperatures of 30C would cause lots of tropical type storms.

 

>>The storm is destroyed by a lack of fuel (warm water); colder temperatures; and yes, even mountains.>>

Yeah...warm oceans cause lots and lots of snow when the moisture gets over land, even if the wind force of the storm lessens.  And this can cause an ice age if it doesn't melt ALL away in the summers.  It seems you must agree with the part about greater precip...even if you doubt the cloud albedo part.  Of course more snows persisting would also increase the albedo. 

More typically, they cause lots of rain and floods when the moisture gets over land.  Remember, at first, there is no land.

 

And yes.... there would be LOTS of precipitation and persistent snow will increase albedo.  That's even part of the conventional model for ice ages.

 

This might now drag out to two more posts .... at most .... then back to Oard's actual claims.....



#239 piasan

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Posted 14 February 2016 - 09:35 AM

>>Consider that the relative humidity in a cloud is 100%.  As temperatures increase, the air is capable of holding more moisture which reduces relative humidity.  With a reduction of relative humidity, the water droplets that make up the cloud will evaporate.>>

I see this as reasonable.  So what would happen to that clear and moist air when it rises up high enough so it cools...as it is fed by massive amounts of warm vapor from below?  Would the air stay clear, or would clouds form?

According to NOAA, in a link previously posted, that warm air will rise until it reaches an altitude where the temperature of the air reaches the dew point.  At that height, the water vapor will condense forming water droplets.  In the process of condensation, more (heat) energy will be released driving the droplets (and the "massive amounts of warm vapor from below" to higher altitudes in a positive feedback loop.  In other words, very tall clouds will form.

 

Is it your view that all or even most of the clouds shown over the warmer parts of the ocean (in the images below) were of the very tall CN type?

It is my view that the very tall CN type would be much more common if global ocean surface temperatures were 30C than they are today.  This view is supported by direct observation of clouds and storms.  No need for speculation on my part here.

 

 

>>If you select that chart, you can get a "video" of the month-by-month changes of surface temperature and cloud cover since January, 2000.  The video demonstrates that cloud cover is closely related to surface temperature.>>

 

 

MODAL2_M_CLD_FR_2009-07.JPEG

 

 

The page does not give surface temps (not that I could find) but it does give the month.  Of course at the lower latitudes, the month doesn't matter a lot.  The above is June of 2009.  I can see clearer skies at the equator in some parts of the globe but just above and below it, there are plenty of clouds.  And to the east of Africa, even at the equator the clouds cover the ocean mostly.  And look how brightly white they are in the Indian Ocean at the equator.  I think what seems apparent to me is the darker (clearer) ocean skies come from the eastward air movements over land from Australia and S. Am....and a little from S. Africa., which affects the S. Indian Ocean a bit.  The warm oceans just to the W of S. Am and N. Africa do not have clearer skies at all.  The images do not support the idea that fewer clouds are present where there is warmer water. 

When I visited the page, there were a number of data sets available listed on the right side of the page.  One of them was surface temperature.  When I clicked on that one, it presented two images.  One was cloud cover, as you posted above.  The other was surface temperature.  It was possible to do a month-by-month comparison for something like the last 15 years.

 

I will grant that the waters east of Brazil and South Africa may be a "cloud shadow" from crossing the continents.  That does not explain the absence of clouds across vast expanses of the tropical Pacific nor does it explain near solid cloud cover west of India... in the "cloud shadow" of the Sahara Desert.  Your image also confirms what I said before.  Except for the polar ice caps, the areas above 40o latitude in both hemispheres snow near total cloud cover while all the large clear expanses (except for polar ice caps) are in the regions below 40o latitude.  It is also noteworthy that the clearest skies run east and west just north of Brazil's bulge (in both the Atlantic and Pacific) and just south of Africa's ..... right along the equator.

 

It is interesting the image posted by you was for June, 2009.  That just happens to be the month Air France 447 crashed in the mid-Atlantic after encountering clouds that reached to 50,000 ft. (15,000 m).  Here's what Wikipedia says about the weather they encountered:

"Weather conditions in the mid-Atlantic were normal for the time of year, and included a broad band of thunderstorms along the Intertropical Convergence Zone (ITCZ).[44] A meteorological analysis of the area surrounding the flight path showed a mesoscale convective system extending to an altitude of around 50,000 feet (15,000 m) above the Atlantic Ocean before Flight 447 disappeared."

 

Notice:  "NORMAL" weather conditions in that region include "a broad band of thunderstorms."  Why do you think clouds reaching to 50,000 feet over the tropical oceans are a problem for me since I've said all along that those clouds that do form will tend to be very tall?  Isn't Oard the one saying there will be an increase in low clouds?

 

It looks like the data destroys Oard's claim that warmer oceans will lead to a significant increase in low level cloud cover.  Can you cite any meteorologists who agree with Oard?

 

If you want me to call "uncle" on this one and since you have noted yourself that even the experts (ie: NASA) seem conflicted on this, I'm quite happy to revert back to my original position of "uncertain" regarding increased cloud cover.  I do NOT, however, accept Oard's claim that increased sea surface temperatures will result in increased low level clouds for reasons we've now been discussing for more than 200 posts.






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