Clouds and nocturnal cooling22-03-2017 18:18 |
Leitwolf★☆☆☆☆ (117) |
Ok .. this is less about opinions and more about facts, and I think this might be interesting. I wanted to have data on nocturnal cooling depending on the condition of the sky. That is, by how much will clouds reduce cooling once night sets in, and what one could possibly derive from this with regard the GHE effect of clouds themselves.
Just to explain the chart. These data were taken a small town in WV called Parkersburg, which was simply the first usefull dataset I ran into (enough moisture, not a metropolitan area..). Every measurement of temperature featured a remark on the condition of the sky. Like CLeaR, FEW clouds, SCaTtered, BroKeN and OVerCast CLR ... 1 FEW ... 2 SCT ... 3 BKN ... 4 OVC ... 5
I assigned the values 1-5 for each condition, and then assigned the average to each night. Then I just grouped these samples and determinded the average for all these groups. The chart shows those groups and the size of the sample (I've have taken two years 2015 and 2016). The sample "1" would only include all clear nights. The x-axis indicates the number of minutes from sunset times 10.
Edited on 22-03-2017 18:19 |
22-03-2017 19:47 |
Into the Night★★★★★ (22643) |
Leitwolf wrote: Ok .. this is less about opinions and more about facts, and I think this might be interesting. I wanted to have data on nocturnal cooling depending on the condition of the sky. That is, by how much will clouds reduce cooling once night sets in, and what one could possibly derive from this with regard the GHE effect of clouds themselves.
Just to explain the chart. These data were taken a small town in WV called Parkersburg, which was simply the first usefull dataset I ran into (enough moisture, not a metropolitan area..). Every measurement of temperature featured a remark on the condition of the sky. Like CLeaR, FEW clouds, SCaTtered, BroKeN and OVerCast CLR ... 1 FEW ... 2 SCT ... 3 BKN ... 4 OVC ... 5
I assigned the values 1-5 for each condition, and then assigned the average to each night. Then I just grouped these samples and determinded the average for all these groups. The chart shows those groups and the size of the sample (I've have taken two years 2015 and 2016). The sample "1" would only include all clear nights. The x-axis indicates the number of minutes from sunset times 10.
Not necessarily due to any 'greenhouse' effect.
There are several problems:
First, you don't know what other factors might be at play. Were the clouds there during the day? Did warmer or colder air move in? Assigning an average to each night is actually producing a biased result.
Clouds are also liquid water. This has the highest specific heat of any common substance. It takes longer to warm up clouds, and longer to cool them down again.
The Parrot Killer
Debunked in my sig. - tmiddles
Google keeps track of paranoid talk and i'm not on their list. I've been evaluated and certified. - keepit
nuclear powered ships do not require nuclear fuel. - Swan
While it is true that fossils do not burn it is also true that fossil fuels burn very well - Swan |
RE: Night in Colorado22-03-2017 20:02 |
Frescomexico★★☆☆☆ (179) |
I am from Denver, and, when the sky is overcast in the winter, the temperature does not fall nearly as much as on a clear night. Is this a greenhouse reflection or a convection containment? |
22-03-2017 22:48 |
Leitwolf★☆☆☆☆ (117) |
Well there is one thing I should note here. Especially with the clear sky scenarios one can clearly see how cooling slows down in the course of the night. Why is that? You need to consider the shape of soil temperature wise. Right at sunset temperatures will be above average, while in the late night, close to the morning, temperatures will be at their lowest. So while deeper soil temperatures will correspond to a long term average, the most upper layers will rather move along with short term (daily/hourly) temperatures. For that reason surface temperatues will fall off faster when they are above long term average, and slower if they are below that average. This pattern is well visible in the chart.
Also for that reason the difference of nocturnal cooling, with regard to clear or overcast, is also larger in early night, right after sunset, as in the later night. It is only 15% early on and moves to 20 -25% in early morning. So the best guess seems, that an average overcast scenario brings down cooling by aobut 20% or below.
One can also plot all the deviations from the clear sky scenarios and one finds that average cooling is just 64% of what it would be if there were no clouds at all, which is an interesting figure.
That means, at least locally, clouds excercise a huge greenhouse effect, much larger than the albedo effect they have globally. Keep in mind, if clouds account for 2/3 of total albedo, they would block 20-21% or solar radiation. If they happen to block 1 - 64% = 36% of local infrared radiation in Parkersburg, WV., that would be a much higher figure.
Now there will be differences between a local situation and the global aggregate. It may well be true, that Parkersburg has a higher "cloudiness" as the global average, thereby we would also have a higher local albedo effect.
Yet, by all I can tell, these results are in strong contradiction to standard climate models, which tell us that the albedo effect of clouds would be far stronger than their GHE. In other words, clouds would massively cool the planet. The data named above however suggest the exact opposite. Clouds rather seem to heat the planet, which of course renders greenhouse gases jobless, if you will. |
22-03-2017 22:52 |
Leitwolf★☆☆☆☆ (117) |
@Fresco
That is a bit funny, because Denver was the first data set I used for that. I knew it was useless (too high, too dry, too large of a city), so I only used it to get the scripts running. But yes, this IS the GHE of clouds, and during day time the albedo effect dominates. Btw. it does not really matter, if it is winter or summer. |
|
23-03-2017 00:12 |
Frescomexico★★☆☆☆ (179) |
I guess you are right, but when you are worrying about your pipes freezing, it is a comfort to have that overcast sky above. |
23-03-2017 10:43 |
Surface Detail★★★★☆ (1673) |
Leitwolf wrote: Well there is one thing I should note here. Especially with the clear sky scenarios one can clearly see how cooling slows down in the course of the night. Why is that? You need to consider the shape of soil temperature wise. Right at sunset temperatures will be above average, while in the late night, close to the morning, temperatures will be at their lowest. So while deeper soil temperatures will correspond to a long term average, the most upper layers will rather move along with short term (daily/hourly) temperatures. For that reason surface temperatues will fall off faster when they are above long term average, and slower if they are below that average. This pattern is well visible in the chart.
Also for that reason the difference of nocturnal cooling, with regard to clear or overcast, is also larger in early night, right after sunset, as in the later night. It is only 15% early on and moves to 20 -25% in early morning. So the best guess seems, that an average overcast scenario brings down cooling by aobut 20% or below.
One can also plot all the deviations from the clear sky scenarios and one finds that average cooling is just 64% of what it would be if there were no clouds at all, which is an interesting figure.
That means, at least locally, clouds excercise a huge greenhouse effect, much larger than the albedo effect they have globally. Keep in mind, if clouds account for 2/3 of total albedo, they would block 20-21% or solar radiation. If they happen to block 1 - 64% = 36% of local infrared radiation in Parkersburg, WV., that would be a much higher figure.
Now there will be differences between a local situation and the global aggregate. It may well be true, that Parkersburg has a higher "cloudiness" as the global average, thereby we would also have a higher local albedo effect.
Yet, by all I can tell, these results are in strong contradiction to standard climate models, which tell us that the albedo effect of clouds would be far stronger than their GHE. In other words, clouds would massively cool the planet. The data named above however suggest the exact opposite. Clouds rather seem to heat the planet, which of course renders greenhouse gases jobless, if you will. Actually, the overall effect of clouds is to cool the planet since the albedo effect of -50 Wm-2 (reflecting sunlight back into space) outweighs their greenhouse effect (radiating IR back to Earth) of +30 Wm-2. It is thought that clouds will contribute a slightly positive feedback as the planet warms (the increase in greenhouse effect greater than the increase in albedo effect), though there is still considerably uncertainty about this.
The chapter from the 2013 IPCC Report dealing with clouds and aerosols can be found here: Clouds and Aerosols |
23-03-2017 16:55 |
Leitwolf★☆☆☆☆ (117) |
50W/341W = 14.66%. So you are putting the albedo effect to only 14.66%, which is less than half of the total terrestial albedo of 0.31. However I could quote a lot of "serious" sources saying that clouds account for about 2/3 of total albedo, meaning they have an albedo effect of roughly 70W/m2. And even that is a very low estimante, given that earth has a clear sky albedo of 0.1.
The surface on the other side emits about 385W/m2. if we take the 30W figure, then 30/385 = 8.8%. So clouds would then have only a tiny warming, or GHE on the other side. The data I provided above show the opposite however. Under a clear sky the surface will not be able to emit all the 385W/m2 into space, but a high fraction of it. And if an all overcast scenario can reduce that cooling by about 80%, that will give us a theoretical maximum of 385 * 0.8 = 308W, and that figure could be 385*0.36 = 138W/m2 on average for clouds GHE. Now again, these are just theoretical maxima derived from the observed data. In reality these figures will be lower for a) the clear sky scenario does not represent perfect emission b) at night there will likely be more clouds than during daytime c) this is just data on Parkersburg, WV, definitely not representing the whole planet d) the 385W figure is also too high, as it would suggest emssivity to be 1, which it is not.
Yet it is fair to say that the 30W/m2 GHE of clouds is non sense. |
23-03-2017 17:25 |
Surface Detail★★★★☆ (1673) |
Leitwolf wrote: 50W/341W = 14.66%. So you are putting the albedo effect to only 14.66%, which is less than half of the total terrestial albedo of 0.31. What is the point of comparing the reduction in incoming solar radiation due to cloud with the terrestrial albedo? That has no physical significance that I can see.
I suggest that you read and understand the IPCC chapter on clouds and aerosols that I linked to (and where my figures come from) before posting more meaningless calculations. |
24-03-2017 05:20 |
Leitwolf★☆☆☆☆ (117) |
@surface detail I suggest you get yourself a brain. Unless that happens, you will not be able to follow to most primitive logics. |
24-03-2017 10:13 |
Surface Detail★★★★☆ (1673) |
Leitwolf wrote: @surface detail I suggest you get yourself a brain. Unless that happens, you will not be able to follow to most primitive logics. What you have posted isn't logical. If it were, you'd be able to answer my question rather than replying with abuse. That doesn't surprise me, though. It's what people who don't know what they're talking about usually do when their bullshit is challenged. |
24-03-2017 19:33 |
Into the Night★★★★★ (22643) |
Surface Detail wrote:
Leitwolf wrote: Well there is one thing I should note here. Especially with the clear sky scenarios one can clearly see how cooling slows down in the course of the night. Why is that? You need to consider the shape of soil temperature wise. Right at sunset temperatures will be above average, while in the late night, close to the morning, temperatures will be at their lowest. So while deeper soil temperatures will correspond to a long term average, the most upper layers will rather move along with short term (daily/hourly) temperatures. For that reason surface temperatues will fall off faster when they are above long term average, and slower if they are below that average. This pattern is well visible in the chart.
Also for that reason the difference of nocturnal cooling, with regard to clear or overcast, is also larger in early night, right after sunset, as in the later night. It is only 15% early on and moves to 20 -25% in early morning. So the best guess seems, that an average overcast scenario brings down cooling by aobut 20% or below.
One can also plot all the deviations from the clear sky scenarios and one finds that average cooling is just 64% of what it would be if there were no clouds at all, which is an interesting figure.
That means, at least locally, clouds excercise a huge greenhouse effect, much larger than the albedo effect they have globally. Keep in mind, if clouds account for 2/3 of total albedo, they would block 20-21% or solar radiation. If they happen to block 1 - 64% = 36% of local infrared radiation in Parkersburg, WV., that would be a much higher figure.
Now there will be differences between a local situation and the global aggregate. It may well be true, that Parkersburg has a higher "cloudiness" as the global average, thereby we would also have a higher local albedo effect.
Yet, by all I can tell, these results are in strong contradiction to standard climate models, which tell us that the albedo effect of clouds would be far stronger than their GHE. In other words, clouds would massively cool the planet. The data named above however suggest the exact opposite. Clouds rather seem to heat the planet, which of course renders greenhouse gases jobless, if you will. Actually, the overall effect of clouds is to cool the planet since the albedo effect of -50 Wm-2 (reflecting sunlight back into space) outweighs their greenhouse effect (radiating IR back to Earth) of +30 Wm-2. It is thought that clouds will contribute a slightly positive feedback as the planet warms (the increase in greenhouse effect greater than the increase in albedo effect), though there is still considerably uncertainty about this.
The chapter from the 2013 IPCC Report dealing with clouds and aerosols can be found here: Clouds and Aerosols
The IPCC does not know what the global effect of clouds is. No one does.
Being liquid water (or ice), clouds absorb infrared, just like the oceans do. Also, being water, the specific heat is the highest of any common material. It takes longer to warm a cloud up, and longer to cool it down.
Clouds do not raise or lower the temperature of the Earth. They can help minimize range of temperature travel, but there is nothing to cause the average to differ.
There is no way to determine what the 24 hour average would have been had the cloud not been there.
The Parrot Killer
Debunked in my sig. - tmiddles
Google keeps track of paranoid talk and i'm not on their list. I've been evaluated and certified. - keepit
nuclear powered ships do not require nuclear fuel. - Swan
While it is true that fossils do not burn it is also true that fossil fuels burn very well - Swan
Edited on 24-03-2017 19:34 |
24-03-2017 22:11 |
Surface Detail★★★★☆ (1673) |
Into the Night wrote:
Surface Detail wrote:
Leitwolf wrote: Well there is one thing I should note here. Especially with the clear sky scenarios one can clearly see how cooling slows down in the course of the night. Why is that? You need to consider the shape of soil temperature wise. Right at sunset temperatures will be above average, while in the late night, close to the morning, temperatures will be at their lowest. So while deeper soil temperatures will correspond to a long term average, the most upper layers will rather move along with short term (daily/hourly) temperatures. For that reason surface temperatues will fall off faster when they are above long term average, and slower if they are below that average. This pattern is well visible in the chart.
Also for that reason the difference of nocturnal cooling, with regard to clear or overcast, is also larger in early night, right after sunset, as in the later night. It is only 15% early on and moves to 20 -25% in early morning. So the best guess seems, that an average overcast scenario brings down cooling by aobut 20% or below.
One can also plot all the deviations from the clear sky scenarios and one finds that average cooling is just 64% of what it would be if there were no clouds at all, which is an interesting figure.
That means, at least locally, clouds excercise a huge greenhouse effect, much larger than the albedo effect they have globally. Keep in mind, if clouds account for 2/3 of total albedo, they would block 20-21% or solar radiation. If they happen to block 1 - 64% = 36% of local infrared radiation in Parkersburg, WV., that would be a much higher figure.
Now there will be differences between a local situation and the global aggregate. It may well be true, that Parkersburg has a higher "cloudiness" as the global average, thereby we would also have a higher local albedo effect.
Yet, by all I can tell, these results are in strong contradiction to standard climate models, which tell us that the albedo effect of clouds would be far stronger than their GHE. In other words, clouds would massively cool the planet. The data named above however suggest the exact opposite. Clouds rather seem to heat the planet, which of course renders greenhouse gases jobless, if you will. Actually, the overall effect of clouds is to cool the planet since the albedo effect of -50 Wm-2 (reflecting sunlight back into space) outweighs their greenhouse effect (radiating IR back to Earth) of +30 Wm-2. It is thought that clouds will contribute a slightly positive feedback as the planet warms (the increase in greenhouse effect greater than the increase in albedo effect), though there is still considerably uncertainty about this.
The chapter from the 2013 IPCC Report dealing with clouds and aerosols can be found here: Clouds and Aerosols
The IPCC does not know what the global effect of clouds is. No one does.
Being liquid water (or ice), clouds absorb infrared, just like the oceans do. Also, being water, the specific heat is the highest of any common material. It takes longer to warm a cloud up, and longer to cool it down.
Clouds do not raise or lower the temperature of the Earth. They can help minimize range of temperature travel, but there is nothing to cause the average to differ.
There is no way to determine what the 24 hour average would have been had the cloud not been there. Good going ITN. You just contradicted yourself in one post. |
25-03-2017 01:01 |
Frescomexico★★☆☆☆ (179) |
A way to observe the surface effect of cooling without the heat conduction from below it to observe the surface of a bridge. |
27-03-2017 00:22 |
Into the Night★★★★★ (22643) |
Surface Detail wrote:
Into the Night wrote:
Surface Detail wrote:
Leitwolf wrote: Well there is one thing I should note here. Especially with the clear sky scenarios one can clearly see how cooling slows down in the course of the night. Why is that? You need to consider the shape of soil temperature wise. Right at sunset temperatures will be above average, while in the late night, close to the morning, temperatures will be at their lowest. So while deeper soil temperatures will correspond to a long term average, the most upper layers will rather move along with short term (daily/hourly) temperatures. For that reason surface temperatues will fall off faster when they are above long term average, and slower if they are below that average. This pattern is well visible in the chart.
Also for that reason the difference of nocturnal cooling, with regard to clear or overcast, is also larger in early night, right after sunset, as in the later night. It is only 15% early on and moves to 20 -25% in early morning. So the best guess seems, that an average overcast scenario brings down cooling by aobut 20% or below.
One can also plot all the deviations from the clear sky scenarios and one finds that average cooling is just 64% of what it would be if there were no clouds at all, which is an interesting figure.
That means, at least locally, clouds excercise a huge greenhouse effect, much larger than the albedo effect they have globally. Keep in mind, if clouds account for 2/3 of total albedo, they would block 20-21% or solar radiation. If they happen to block 1 - 64% = 36% of local infrared radiation in Parkersburg, WV., that would be a much higher figure.
Now there will be differences between a local situation and the global aggregate. It may well be true, that Parkersburg has a higher "cloudiness" as the global average, thereby we would also have a higher local albedo effect.
Yet, by all I can tell, these results are in strong contradiction to standard climate models, which tell us that the albedo effect of clouds would be far stronger than their GHE. In other words, clouds would massively cool the planet. The data named above however suggest the exact opposite. Clouds rather seem to heat the planet, which of course renders greenhouse gases jobless, if you will. Actually, the overall effect of clouds is to cool the planet since the albedo effect of -50 Wm-2 (reflecting sunlight back into space) outweighs their greenhouse effect (radiating IR back to Earth) of +30 Wm-2. It is thought that clouds will contribute a slightly positive feedback as the planet warms (the increase in greenhouse effect greater than the increase in albedo effect), though there is still considerably uncertainty about this.
The chapter from the 2013 IPCC Report dealing with clouds and aerosols can be found here: Clouds and Aerosols
The IPCC does not know what the global effect of clouds is. No one does.
Being liquid water (or ice), clouds absorb infrared, just like the oceans do. Also, being water, the specific heat is the highest of any common material. It takes longer to warm a cloud up, and longer to cool it down.
Clouds do not raise or lower the temperature of the Earth. They can help minimize range of temperature travel, but there is nothing to cause the average to differ.
There is no way to determine what the 24 hour average would have been had the cloud not been there. Good going ITN. You just contradicted yourself in one post.
Nope. The IPCC doesn't know the global effect of clouds. No one does. This is to say the IPCC doesn't know the cloud cover at any particular moment, can't use any such data to determine what the effect of all clouds does to the global temperature, since we can't measure either cloud cover or global temperature, and cannot make predictions on any kind of useful formula.
We do know that clouds are not themselves energy sources or sinks. There is nothing about them that would increase or decrease the energy of the land underneath a cloud. We also not that areas with greater cloud cover tend to have temperature that don't range as far as areas without cloud cover.
There is no paradox as you claim.
The Parrot Killer
Debunked in my sig. - tmiddles
Google keeps track of paranoid talk and i'm not on their list. I've been evaluated and certified. - keepit
nuclear powered ships do not require nuclear fuel. - Swan
While it is true that fossils do not burn it is also true that fossil fuels burn very well - Swan
Edited on 27-03-2017 00:22 |
|
27-03-2017 00:53 |
Frescomexico★★☆☆☆ (179) |
Into the Night wrote: "We do know that clouds are not themselves energy sources or sinks. There is nothing about them that would increase or decrease the energy of the land underneath a cloud. We also not that areas with greater cloud cover tend to have temperature that don't range as far as areas without cloud cover."
It is true that clouds are not energy sources, but they do provide insulation against radiation leaving the land, thereby keeping it warmer than if they were absent. |
27-03-2017 00:56 |
Surface Detail★★★★☆ (1673) |
Into the Night wrote:
Surface Detail wrote:
Into the Night wrote:
Surface Detail wrote:
Leitwolf wrote: Well there is one thing I should note here. Especially with the clear sky scenarios one can clearly see how cooling slows down in the course of the night. Why is that? You need to consider the shape of soil temperature wise. Right at sunset temperatures will be above average, while in the late night, close to the morning, temperatures will be at their lowest. So while deeper soil temperatures will correspond to a long term average, the most upper layers will rather move along with short term (daily/hourly) temperatures. For that reason surface temperatues will fall off faster when they are above long term average, and slower if they are below that average. This pattern is well visible in the chart.
Also for that reason the difference of nocturnal cooling, with regard to clear or overcast, is also larger in early night, right after sunset, as in the later night. It is only 15% early on and moves to 20 -25% in early morning. So the best guess seems, that an average overcast scenario brings down cooling by aobut 20% or below.
One can also plot all the deviations from the clear sky scenarios and one finds that average cooling is just 64% of what it would be if there were no clouds at all, which is an interesting figure.
That means, at least locally, clouds excercise a huge greenhouse effect, much larger than the albedo effect they have globally. Keep in mind, if clouds account for 2/3 of total albedo, they would block 20-21% or solar radiation. If they happen to block 1 - 64% = 36% of local infrared radiation in Parkersburg, WV., that would be a much higher figure.
Now there will be differences between a local situation and the global aggregate. It may well be true, that Parkersburg has a higher "cloudiness" as the global average, thereby we would also have a higher local albedo effect.
Yet, by all I can tell, these results are in strong contradiction to standard climate models, which tell us that the albedo effect of clouds would be far stronger than their GHE. In other words, clouds would massively cool the planet. The data named above however suggest the exact opposite. Clouds rather seem to heat the planet, which of course renders greenhouse gases jobless, if you will. Actually, the overall effect of clouds is to cool the planet since the albedo effect of -50 Wm-2 (reflecting sunlight back into space) outweighs their greenhouse effect (radiating IR back to Earth) of +30 Wm-2. It is thought that clouds will contribute a slightly positive feedback as the planet warms (the increase in greenhouse effect greater than the increase in albedo effect), though there is still considerably uncertainty about this.
The chapter from the 2013 IPCC Report dealing with clouds and aerosols can be found here: Clouds and Aerosols
The IPCC does not know what the global effect of clouds is. No one does.
Being liquid water (or ice), clouds absorb infrared, just like the oceans do. Also, being water, the specific heat is the highest of any common material. It takes longer to warm a cloud up, and longer to cool it down.
Clouds do not raise or lower the temperature of the Earth. They can help minimize range of temperature travel, but there is nothing to cause the average to differ.
There is no way to determine what the 24 hour average would have been had the cloud not been there. Good going ITN. You just contradicted yourself in one post.
Nope. The IPCC doesn't know the global effect of clouds. No one does. This is to say the IPCC doesn't know the cloud cover at any particular moment, can't use any such data to determine what the effect of all clouds does to the global temperature, since we can't measure either cloud cover or global temperature, and cannot make predictions on any kind of useful formula.
We do know that clouds are not themselves energy sources or sinks. There is nothing about them that would increase or decrease the energy of the land underneath a cloud. We also not that areas with greater cloud cover tend to have temperature that don't range as far as areas without cloud cover.
There is no paradox as you claim. You simultaneously claimed that no-one knows the global effect of clouds and that clouds do not raise or lower the temperature of the Earth. These are contradictory statements, and no amount of waffle can change that. |
27-03-2017 00:59 |
Surface Detail★★★★☆ (1673) |
Frescomexico wrote: Into the Night wrote: "We do know that clouds are not themselves energy sources or sinks. There is nothing about them that would increase or decrease the energy of the land underneath a cloud. We also not that areas with greater cloud cover tend to have temperature that don't range as far as areas without cloud cover."
It is true that clouds are not energy sources, but they do provide insulation against radiation leaving the land, thereby keeping it warmer than if they were absent. Exactly. That's why cloudy nights are usually mild. Clouds are good absorbers of IR radiation emitted by the Earth, and they emit some of what they absorb back down again. The overall effect of this is to act as an insulator. |
27-03-2017 20:33 |
Into the Night★★★★★ (22643) |
Surface Detail wrote:
Into the Night wrote:
Surface Detail wrote:
Into the Night wrote:
Surface Detail wrote:
Leitwolf wrote: Well there is one thing I should note here. Especially with the clear sky scenarios one can clearly see how cooling slows down in the course of the night. Why is that? You need to consider the shape of soil temperature wise. Right at sunset temperatures will be above average, while in the late night, close to the morning, temperatures will be at their lowest. So while deeper soil temperatures will correspond to a long term average, the most upper layers will rather move along with short term (daily/hourly) temperatures. For that reason surface temperatues will fall off faster when they are above long term average, and slower if they are below that average. This pattern is well visible in the chart.
Also for that reason the difference of nocturnal cooling, with regard to clear or overcast, is also larger in early night, right after sunset, as in the later night. It is only 15% early on and moves to 20 -25% in early morning. So the best guess seems, that an average overcast scenario brings down cooling by aobut 20% or below.
One can also plot all the deviations from the clear sky scenarios and one finds that average cooling is just 64% of what it would be if there were no clouds at all, which is an interesting figure.
That means, at least locally, clouds excercise a huge greenhouse effect, much larger than the albedo effect they have globally. Keep in mind, if clouds account for 2/3 of total albedo, they would block 20-21% or solar radiation. If they happen to block 1 - 64% = 36% of local infrared radiation in Parkersburg, WV., that would be a much higher figure.
Now there will be differences between a local situation and the global aggregate. It may well be true, that Parkersburg has a higher "cloudiness" as the global average, thereby we would also have a higher local albedo effect.
Yet, by all I can tell, these results are in strong contradiction to standard climate models, which tell us that the albedo effect of clouds would be far stronger than their GHE. In other words, clouds would massively cool the planet. The data named above however suggest the exact opposite. Clouds rather seem to heat the planet, which of course renders greenhouse gases jobless, if you will. Actually, the overall effect of clouds is to cool the planet since the albedo effect of -50 Wm-2 (reflecting sunlight back into space) outweighs their greenhouse effect (radiating IR back to Earth) of +30 Wm-2. It is thought that clouds will contribute a slightly positive feedback as the planet warms (the increase in greenhouse effect greater than the increase in albedo effect), though there is still considerably uncertainty about this.
The chapter from the 2013 IPCC Report dealing with clouds and aerosols can be found here: Clouds and Aerosols
The IPCC does not know what the global effect of clouds is. No one does.
Being liquid water (or ice), clouds absorb infrared, just like the oceans do. Also, being water, the specific heat is the highest of any common material. It takes longer to warm a cloud up, and longer to cool it down.
Clouds do not raise or lower the temperature of the Earth. They can help minimize range of temperature travel, but there is nothing to cause the average to differ.
There is no way to determine what the 24 hour average would have been had the cloud not been there. Good going ITN. You just contradicted yourself in one post.
Nope. The IPCC doesn't know the global effect of clouds. No one does. This is to say the IPCC doesn't know the cloud cover at any particular moment, can't use any such data to determine what the effect of all clouds does to the global temperature, since we can't measure either cloud cover or global temperature, and cannot make predictions on any kind of useful formula.
We do know that clouds are not themselves energy sources or sinks. There is nothing about them that would increase or decrease the energy of the land underneath a cloud. We also not that areas with greater cloud cover tend to have temperature that don't range as far as areas without cloud cover.
There is no paradox as you claim. You simultaneously claimed that no-one knows the global effect of clouds and that clouds do not raise or lower the temperature of the Earth. These are contradictory statements, and no amount of waffle can change that.
Then enjoy for catching me in a 'paradox'. I still stand by both statements.
The Parrot Killer
Debunked in my sig. - tmiddles
Google keeps track of paranoid talk and i'm not on their list. I've been evaluated and certified. - keepit
nuclear powered ships do not require nuclear fuel. - Swan
While it is true that fossils do not burn it is also true that fossil fuels burn very well - Swan |
27-03-2017 20:35 |
Into the Night★★★★★ (22643) |
Surface Detail wrote:
Frescomexico wrote: Into the Night wrote: "We do know that clouds are not themselves energy sources or sinks. There is nothing about them that would increase or decrease the energy of the land underneath a cloud. We also not that areas with greater cloud cover tend to have temperature that don't range as far as areas without cloud cover."
It is true that clouds are not energy sources, but they do provide insulation against radiation leaving the land, thereby keeping it warmer than if they were absent. Exactly. That's why cloudy nights are usually mild. Clouds are good absorbers of IR radiation emitted by the Earth, and they emit some of what they absorb back down again. The overall effect of this is to act as an insulator.
Clouds absorb IR radiation from everywhere, including the Sun. It is the Sun's IR that warms them, just like the Sun's IR that warms the Earth.
Clouds do not as as insulation of any kind. If anything, they conduct heat better than dry air.
I think you probably have a distorted view of what specific heat is.
The Parrot Killer
Debunked in my sig. - tmiddles
Google keeps track of paranoid talk and i'm not on their list. I've been evaluated and certified. - keepit
nuclear powered ships do not require nuclear fuel. - Swan
While it is true that fossils do not burn it is also true that fossil fuels burn very well - Swan |
27-03-2017 23:21 |
Surface Detail★★★★☆ (1673) |
Into the Night wrote:
Surface Detail wrote:
Frescomexico wrote: Into the Night wrote: "We do know that clouds are not themselves energy sources or sinks. There is nothing about them that would increase or decrease the energy of the land underneath a cloud. We also not that areas with greater cloud cover tend to have temperature that don't range as far as areas without cloud cover."
It is true that clouds are not energy sources, but they do provide insulation against radiation leaving the land, thereby keeping it warmer than if they were absent. Exactly. That's why cloudy nights are usually mild. Clouds are good absorbers of IR radiation emitted by the Earth, and they emit some of what they absorb back down again. The overall effect of this is to act as an insulator.
Clouds absorb IR radiation from everywhere, including the Sun. It is the Sun's IR that warms them, just like the Sun's IR that warms the Earth.
Clouds do not as as insulation of any kind. If anything, they conduct heat better than dry air.
I think you probably have a distorted view of what specific heat is. This has little to do with specific heat.
At night, when the skies are clear, the IR radiation emitted by the Earth (that isn't absorbed by greenhouse gases) travels straight into space.
When it is cloudy, this IR is absorbed by water droplets making up the clouds, thus warming them. The warmed clouds then also emit IR, some of which travels downwards, thus warming the ground. The net effect is that less energy escapes into space when it is cloudy, and the ground surface remains warmer. |
27-03-2017 23:45 |
Into the Night★★★★★ (22643) |
Surface Detail wrote:
Into the Night wrote:
Surface Detail wrote:
Frescomexico wrote: Into the Night wrote: "We do know that clouds are not themselves energy sources or sinks. There is nothing about them that would increase or decrease the energy of the land underneath a cloud. We also not that areas with greater cloud cover tend to have temperature that don't range as far as areas without cloud cover."
It is true that clouds are not energy sources, but they do provide insulation against radiation leaving the land, thereby keeping it warmer than if they were absent. Exactly. That's why cloudy nights are usually mild. Clouds are good absorbers of IR radiation emitted by the Earth, and they emit some of what they absorb back down again. The overall effect of this is to act as an insulator.
Clouds absorb IR radiation from everywhere, including the Sun. It is the Sun's IR that warms them, just like the Sun's IR that warms the Earth.
Clouds do not as as insulation of any kind. If anything, they conduct heat better than dry air.
I think you probably have a distorted view of what specific heat is. This has little to do with specific heat.
At night, when the skies are clear, the IR radiation emitted by the Earth (that isn't absorbed by greenhouse gases) travels straight into space.
When it is cloudy, this IR is absorbed by water droplets making up the clouds, thus warming them. The warmed clouds then also emit IR, some of which travels downwards, thus warming the ground. The net effect is that less energy escapes into space when it is cloudy, and the ground surface remains warmer.
Hey dumbass...did you know that IR emissions is the least effective way of cooling the surface of the Earth? That's right! Conduction and convection are!
Did you also know that you CAN'T reduce radiance and warm the Earth at the same time?
Clouds are just areas of liquid water. They conduct heat just like everything else. Better than dry air even.
The specific heat index of water keeps the cloud itself from warming or cooling as rapidly as dry air.
You are just making the 'Magick Bouncing Photon' and 'Magick Blanket' arguments with water instead of carbon dioxide. They don't work without violating physical laws in either case.
The Parrot Killer
Debunked in my sig. - tmiddles
Google keeps track of paranoid talk and i'm not on their list. I've been evaluated and certified. - keepit
nuclear powered ships do not require nuclear fuel. - Swan
While it is true that fossils do not burn it is also true that fossil fuels burn very well - Swan |
30-04-2017 01:34 |
LifeIsThermal☆☆☆☆☆ (39) |
Surface Detail wrote:
At night, when the skies are clear, the IR radiation emitted by the Earth (that isn't absorbed by greenhouse gases) travels straight into space.
When it is cloudy, this IR is absorbed by water droplets making up the clouds, thus warming them. The warmed clouds then also emit IR, some of which travels downwards, thus warming the ground. The net effect is that less energy escapes into space when it is cloudy, and the ground surface remains warmer.
You really think the surface cares about how cold the atmosphere is? Like: Oh no, it is a bit to hot up there, I´ll hold in some photons.
Really?
A bodys temperature does not depend on how much energy escapes. The emission of the surface is only connected to the internal temperature. It a relationship that is independent of everything else. Read the theory of thermal energy and how temperature and emission is a couple dancing alone. If you make arguments about temperature we can actually demand that you read the theory that exactly defines temperature. It is not even hard. |
30-04-2017 02:20 |
Surface Detail★★★★☆ (1673) |
LifeIsThermal wrote:
Surface Detail wrote:
At night, when the skies are clear, the IR radiation emitted by the Earth (that isn't absorbed by greenhouse gases) travels straight into space.
When it is cloudy, this IR is absorbed by water droplets making up the clouds, thus warming them. The warmed clouds then also emit IR, some of which travels downwards, thus warming the ground. The net effect is that less energy escapes into space when it is cloudy, and the ground surface remains warmer.
You really think the surface cares about how cold the atmosphere is? Like: Oh no, it is a bit to hot up there, I´ll hold in some photons.
Really?
No, I'm not saying that at all. Please read my post more carefully. |
30-04-2017 03:04 |
LifeIsThermal☆☆☆☆☆ (39) |
Surface Detail wrote:
LifeIsThermal wrote:
Surface Detail wrote:
The net effect is that less energy escapes into space when it is cloudy, and the ground surface remains warmer.
No, I'm not saying that at all. Please read my post more carefully.
Ok. Are you really saying that the amount of heat emitted by the surface is affected by an external lower temperature, low density body, that is positioned between the ultimate heat sink of space vacuum at 3K and the surface?
Really? |
30-04-2017 03:11 |
Surface Detail★★★★☆ (1673) |
LifeIsThermal wrote:
Surface Detail wrote:
LifeIsThermal wrote:
Surface Detail wrote:
The net effect is that less energy escapes into space when it is cloudy, and the ground surface remains warmer.
No, I'm not saying that at all. Please read my post more carefully.
Ok. Are you really saying that the amount of heat emitted by the surface is affected by an external lower temperature, low density body, that is positioned between the ultimate heat sink of space vacuum at 3K and the surface?
Really? Yes.
That body is also emitting radiation, some of which reaches the surface. This means that the surface is receiving radiation that it would not receive if the body were not there. This radiation warms the surface a little, so that it then emits more radiation than it would do if the body were not there. |
30-04-2017 11:55 |
Tim the plumber★★★★☆ (1361) |
LifeIsThermal wrote:
Surface Detail wrote:
LifeIsThermal wrote:
Surface Detail wrote:
The net effect is that less energy escapes into space when it is cloudy, and the ground surface remains warmer.
No, I'm not saying that at all. Please read my post more carefully.
Ok. Are you really saying that the amount of heat emitted by the surface is affected by an external lower temperature, low density body, that is positioned between the ultimate heat sink of space vacuum at 3K and the surface?
Really?
Whilst the body radiates the same heat some is reflected back by the clouds. Thus there is less net radiation.
Does that work? |
01-05-2017 00:15 |
Leitwolf★☆☆☆☆ (117) |
Surface Detail wrote: When it is cloudy, this IR is absorbed by water droplets making up the clouds, thus warming them. The warmed clouds then also emit IR, some of which travels downwards, thus warming the ground. The net effect is that less energy escapes into space when it is cloudy, and the ground surface remains warmer.
That is NOT what happens. Clouds do not get heated and then reemit radiation. Mainly they simply reflect radiation.
If it was the other way round, you would just get the emissions of clouds which are more or less high above the ground, where it is much colder anyway. These cold clouds would hardly be able to substantially "heat" the surface. Also, and that is the funny part, if at all, the lower the clouds the warmer they will be, and thus the stronger their heating effect would turn out. This is ironic because it is the exact opposite of what the IPCC says. Namely the higher the cloud, the stronger the heating..
So let us just keep it simple an logic. Clouds are REFLECTING radiation. |
01-05-2017 01:23 |
Surface Detail★★★★☆ (1673) |
Leitwolf wrote:
Surface Detail wrote: When it is cloudy, this IR is absorbed by water droplets making up the clouds, thus warming them. The warmed clouds then also emit IR, some of which travels downwards, thus warming the ground. The net effect is that less energy escapes into space when it is cloudy, and the ground surface remains warmer.
That is NOT what happens. Clouds do not get heated and then reemit radiation. Mainly they simply reflect radiation.
If it was the other way round, you would just get the emissions of clouds which are more or less high above the ground, where it is much colder anyway. These cold clouds would hardly be able to substantially "heat" the surface. Also, and that is the funny part, if at all, the lower the clouds the warmer they will be, and thus the stronger their heating effect would turn out. This is ironic because it is the exact opposite of what the IPCC says. Namely the higher the cloud, the stronger the heating..
So let us just keep it simple an logic. Clouds are REFLECTING radiation. While clouds are indeed good reflectors of visible radiation, the same does not apply to the IR radiation that we are discussing here. Clouds are good absorbers (and hence good emitters) of IR radiation. This means that they absorb most IR that strikes them, and they emit IR according to their temperature. Their equilibrium temperature will be that at which they emit the same amount of radiation as they are absorbing. |