Fall Nights Are Warming in Our Changing Climate

[Quaestio]

Nothing but guesswork on your part. Water vapor is a greenhouse gas. Your statements imply that you lack an understanding of that concept. Perhaps the aforementioned Climatology education is a good idea?

The Dunning Kruger effect runs strong in him. Climate truthers are a weird lot.

 

[Lord of Planar]

Riiiiiiight

Climate scientists are well aware of both positive and negative feedbacks. The net result is positive, thus they... wait for it... focus on the positive. (I'd say they are really putting their efforts into reducing the uncertainties, that seems to be the primary focus at this time. Anyway....) A typical example from IPCC AR5, Chapter 7 (60 pages dedicated to discussions of clouds and aerosols):

The net feedback from water vapour and lapse rate changes
combined, as traditionally defined, is extremely likely positive
(amplifying global climate changes). The sign of the net radiative
feedback due to all cloud types is less certain but likely
positive. Uncertainty in the sign and magnitude of the cloud
feedback is due primarily to continuing uncertainty in the
impact of warming on low clouds. We estimate the water vapour
plus lapse rate feedback to be +1.1 (+0.9 to +1.3) W m−2 °C−1 and
the cloud feedback from all cloud types to be +0.6 (−0.2 to +2.0) W
m–2 °C–1. These ranges are broader than those of climate models to
account for additional uncertainty associated with processes that may
not have been accounted for in those models. The mean values and
ranges in climate models are essentially unchanged since AR4, but are
now supported by stronger indirect observational evidence and better
process understanding, especially for water vapour. Low clouds contribute
positive feedback in most models, but that behaviour is not well
understood, nor effectively constrained by observations, so we are not
confident that it is realistic. {7.2.4, 7.2.5, 7.2.6, Figures 7.9 to 7.11}.

The sign of the net radiative
feedback due to all cloud types is less certain but likely
positive.

Yes, yes, yes. Radiative feedback is likely positive with clouds.

THAT DOES NOT ADDRESS MY CLAIM!!!

Once again, for everyone who cannot see outside the box, that the alarmists placed you in.

Clouds dramatically reduce the solar energy that hits the surface.

It might surprise you to learn, that the sun, heating up the surface, is what supplies the upward IR that the clouds see!

It might surprise you to learn, when more clouds block more of the surface from direct sunlight... There is less every to drive the greenhouse effect.

It might surprise you to learn, that for every 1% of decreased upward IR, the greenhouse effect diminished by over 1.5 W/m^2!

I have never seen literature to address this. Like the paragraph quoted before, they keep the solar value striking the earth "unperturbed." By doing so, they eliminate an inconvenient variable.

 

[Visbek]

Yes, yes, yes. Radiative feedback is likely positive with clouds.

THAT DOES NOT ADDRESS MY CLAIM!!!

Uh... Yeah. It does. Since you seem to need this explicitly spelled out for you:

• You claimed that climate scientists ignore the negative feedbacks of increased cloud formation. This is patently false.

• You claimed that they focus too much on the positive feedbacks. Again, this is patently false. They pay attention to both cooling and warming, positive and negative feedbacks. That's the only way to reduce the uncertainties.

• The paragraph I cited is a summary, which points out that the net effect of increased water vapor in the atmosphere is positive. You do understand that a) the point was that the net effect is positive, and b) it is not possible to boil down all the scientific information of a 60-page summary into one paragraph, right?

• You obviously didn't bother to read the referenced chapter. Nor is it clear that you've read... much of anything on the topic.

Clouds dramatically reduce the solar energy that hits the surface.

Yes, and they also trap heat in the atmosphere. The net effect, at this time, is that clouds cool the climate. Unfortunately, the changes we expect to see in clouds and cloud formation are likely to exacerbate global warming, not result in more cooling.

It might surprise you to learn, that the sun, heating up the surface, is what supplies the upward IR that the clouds see!

:roll:

It might surprise you to learn, when more clouds block more of the surface from direct sunlight... There is less every to drive the greenhouse effect.

It doesn't surprise me at all, and more importantly, it doesn't surprise the climate scientists who actually work on the issue. It might surprise you to learn that clouds do not have one oversimplified effect on the climate, and that an increase in cloud formation will not have one simple impact of "more cooling." If you'd bothered to read the AR5 chapter I referenced, you might have learned that.

It might surprise you to learn, that for every 1% of decreased upward IR, the greenhouse effect diminished by over 1.5 W/m^2!

Uh huh. What's your source for this claim? Do you have access to some Magic Science that climate scientists and the IPCC does not? And assuming that your claim is in the right ballpark, do you really think they're ignoring those kinds of impacts in their evaluations and models?

I have never seen literature to address this.

I think you're just not looking.

 

[Lord of Planar]

Uh... Yeah. It does. Since you seem to need this explicitly spelled out for you:

• You claimed that climate scientists ignore the negative feedbacks of increased cloud formation. This is patently false.

Wrong. I acknowledge clouds play a positive reedback to upward IR. I am pointing out that as clouds cover more of the surface they also reduce the solar energy striking the earth, and reflecting more into space.

Changes in cloud formations effectively change the earths albedo. but it is held constant.

• You claimed that they focus too much on the positive feedbacks. Again, this is patently false. They pay attention to both cooling and warming, positive and negative feedbacks. That's the only way to reduce the uncertainties.

I'm sorry that you have difficulty comprehending what people say. I never made such a claim. There is no "too much." Again, they simply do not consider the solar value hitting the earth to change, and the part I pointed out in an IPCC quote even says so.

• The paragraph I cited is a summary, which points out that the net effect of increased water vapor in the atmosphere is positive. You do understand that a) the point was that the net effect is positive, and b) it is not possible to boil down all the scientific information of a 60-page summary into one paragraph, right?

Yes, I completely understand and agree with that the net effect is positive feedback to the upward IR. Now why do you have a difficulty understanding things your masters don't tell you?

• You obviously didn't bother to read the referenced chapter. Nor is it clear that you've read... much of anything on the topic.

They acknowledge it and don't model it. What does that tell you?

Yes, and they also trap heat in the atmosphere. The net effect, at this time, is that clouds cool the climate. Unfortunately, the changes we expect to see in clouds and cloud formation are likely to exacerbate global warming, not result in more cooling.

Maybe they do, but impossible to say with certainty. What is certain is we don't see the level of H2O feedback claimed in the temperature record.

It doesn't surprise me at all, and more importantly, it doesn't surprise the climate scientists who actually work on the issue. It might surprise you to learn that clouds do not have one oversimplified effect on the climate, and that an increase in cloud formation will not have one simple impact of "more cooling." If you'd bothered to read the AR5 chapter I referenced, you might have learned that.

I know all this. They conveniently leave it out, as they cherry pick other variables to use as well.

Uh huh. What's your source for this claim? Do you have access to some Magic Science that climate scientists and the IPCC does not? And assuming that your claim is in the right ballpark, do you really think they're ignoring those kinds of impacts in their evaluations and models?

It's simple math. It's a near linear result between upward IR and the flux in the greenhouse effect.

I don't need a peer reviewed paper to or pundit to tell me something as simple as 2 x 2 = 4.

 

[Visbek]

Wrong. I acknowledge clouds play a positive reedback to upward IR. I am pointing out that as clouds cover more of the surface they also reduce the solar energy striking the earth, and reflecting more into space.

Good news, everyone! Climate scientists are well aware of this basic concept, and yes they include this in their understandings, models and predictions. However, the situation is considerably more complex than "more clouds means more cooling, end of story."

Changes in cloud formations effectively change the earths albedo. but it is held constant.

OK then. Prove it. A claim like that must ultimately be backed by empirical observation, not woo numbers in your own private spreadsheet.

While you are proving it: You do remember that the altitude of the clouds has an impact on whether those new clouds reflect solar radiation, or trap heat in the atmosphere, yes? (E.g. if more clouds form high in the atmosphere, this will not result in more cooling, but more warming.) You do know that the thickness of clouds impacts the cooling or warming effect, right? (E.g. Thick clouds tend to reflect more solar radiation.) You do recall that all clouds will trap more nighttime heat, yes? (E.g. those thick clouds which reflect solar radiation during the day also trap heat at night.) You do recall that one of the reasons you'd get more cloud formation is because there is more water vapor in the atmosphere, and that since water vapor is a major GHG, that condition increases global temperatures?

I'm just scratching the surface here. Again, this is an incredibly complex aspect of climate change. Scientists aren't ignoring the cooling impact of clouds -- if they did, their models wouldn't even work with basic hindcasting. Additional cloud formation is not happening in complete isolation from other parameters which, in turn, impact the causes of cloud formation. As already noted, this loop of influences is why modeling changes in clouds is so complex and uncertain. I.e. the overall the impact of increased cloud formation is not a simple linear calculation, and it is foolish and/or ignorant to suggest otherwise.

They acknowledge it and don't model it. What does that tell you?

Prove it. Be specific. Cite your sources. Identify the models that leave out increases in the cooling effects due additional cloud formation. Then, explain why their models aren't off by, oh, 5º C.

It's simple math. It's a near linear result between upward IR and the flux in the greenhouse effect.

Nope, nope, "simple math" does not work here. As I've hinted at here, and as actual climate scientists explain in FAR more detail: Changes in clouds is incredibly complex. If you're going to make a specific claim like "for every 1% of decreased upward IR, the greenhouse effect diminished by over 1.5 W/m^2" you need to have actual sources and empirical confirmation. So where is your proof?

 

[longview]

Good news, everyone! Climate scientists are well aware of this basic concept, and yes they include this in their understandings, models and predictions. However, the situation is considerably more complex than "more clouds means more cooling, end of story."



OK then. Prove it. A claim like that must ultimately be backed by empirical observation, not woo numbers in your own private spreadsheet.

While you are proving it: You do remember that the altitude of the clouds has an impact on whether those new clouds reflect solar radiation, or trap heat in the atmosphere, yes? (E.g. if more clouds form high in the atmosphere, this will not result in more cooling, but more warming.) You do know that the thickness of clouds impacts the cooling or warming effect, right? (E.g. Thick clouds tend to reflect more solar radiation.) You do recall that all clouds will trap more nighttime heat, yes? (E.g. those thick clouds which reflect solar radiation during the day also trap heat at night.) You do recall that one of the reasons you'd get more cloud formation is because there is more water vapor in the atmosphere, and that since water vapor is a major GHG, that condition increases global temperatures?

I'm just scratching the surface here. Again, this is an incredibly complex aspect of climate change. Scientists aren't ignoring the cooling impact of clouds -- if they did, their models wouldn't even work with basic hindcasting. Additional cloud formation is not happening in complete isolation from other parameters which, in turn, impact the causes of cloud formation. As already noted, this loop of influences is why modeling changes in clouds is so complex and uncertain. I.e. the overall the impact of increased cloud formation is not a simple linear calculation, and it is foolish and/or ignorant to suggest otherwise.



Prove it. Be specific. Cite your sources. Identify the models that leave out increases in the cooling effects due additional cloud formation. Then, explain why their models aren't off by, oh, 5º C.



Nope, nope, "simple math" does not work here. As I've hinted at here, and as actual climate scientists explain in FAR more detail: Changes in clouds is incredibly complex. If you're going to make a specific claim like "for every 1% of decreased upward IR, the greenhouse effect diminished by over 1.5 W/m^2" you need to have actual sources and empirical confirmation. So where is your proof?

From Chapter 7 of AR5 they say that clouds on average have a net cooling effect.
https://www.ipcc.ch/pdf/assessment-report/ar5/wg1/WG1AR5_Chapter07_FINAL.pdf

7.2.1.2 Effects of Clouds on the Earth’s Radiation Budget
The effect of clouds on the Earth’s present-day top of the atmosphere
(TOA) radiation budget, or cloud radiative effect (CRE), can be inferred
from satellite data by comparing upwelling radiation in cloudy and
non-cloudy conditions (Ramanathan et al., 1989). By enhancing the
planetary albedo, cloudy conditions exert a global and annual shortwave
cloud radiative effect (SWCRE) of approximately –50 W m–2 and,
by contributing to the greenhouse effect, exert a mean longwave effect
(LWCRE) of approximately +30 W m–2, with a range of 10% or less
between published satellite estimates (Loeb et al., 2009). Some of the
apparent LWCRE comes from the enhanced water vapour coinciding
with the natural cloud fluctuations used to measure the effect, so the
true cloud LWCRE is about 10% smaller (Sohn et al., 2010). The net
global mean CRE of approximately –20 W m–2 implies a net cooling
effect of clouds on the current climate.

They go on to say,

7.2.2 Cloud Process Modelling
Cloud formation processes span scales from the sub-micrometre scale
of CCN, to cloud-system scales of up to thousands of kilometres. This
range of scales is impossible to resolve with numerical simulations
on computers, and this is not expected to change in the foreseeable future.

Figure 7.7 panel C further shows the Net (global mean = –21.1 W m-2)

 

[Visbek]

From Chapter 7 of AR5 they say that clouds on average have a net cooling effect.

Yes, we know that. Climate scientists know it. The IPCC knows it. The scientists developing computer models know it. And we're talking about feedbacks, not current conditions. So.... What's your point?

They go on to say....

You can't even read an entire paragraph? Seriously?

Cloud formation processes span scales from the sub-micrometre scale
of CCN, to cloud-system scales of up to thousands of kilometres. This
range of scales is impossible to resolve with numerical simulations
on computers, and this is not expected to change in the foreseeable
future. Nonetheless progress has been made through a variety of modelling
strategies, which are outlined briefly in this section, followed by
a discussion in Section 7.2.3 of developments in representing clouds
in global models. The implications of these discussions are synthesized
in Section 7.2.3.5.

Anyway... Since you missed it, the IPCC is not only aware of the cooling that they discuss, they are also aware of the uncertainties when dealing with clouds that they discuss. Despite those uncertainties with clouds, they find that the net feedback from water vapor and lapse rate changes are extremely likely to be a net positive. If you actually read the chapter, you should see how they arrive at that conclusion.

 

[longview]

Yes, we know that. Climate scientists know it. The IPCC knows it. The scientists developing computer models know it. And we're talking about feedbacks, not current conditions. So.... What's your point?



You can't even read an entire paragraph? Seriously?

Cloud formation processes span scales from the sub-micrometre scale
of CCN, to cloud-system scales of up to thousands of kilometres. This
range of scales is impossible to resolve with numerical simulations
on computers, and this is not expected to change in the foreseeable
future. Nonetheless progress has been made through a variety of modelling
strategies, which are outlined briefly in this section, followed by
a discussion in Section 7.2.3 of developments in representing clouds
in global models. The implications of these discussions are synthesized
in Section 7.2.3.5.

Anyway... Since you missed it, the IPCC is not only aware of the cooling that they discuss, they are also aware of the uncertainties when dealing with clouds that they discuss. Despite those uncertainties with clouds, they find that the net feedback from water vapor and lapse rate changes are extremely likely to be a net positive. If you actually read the chapter, you should see how they arrive at that conclusion.

I was being kind!
You then went and quoted the portion where they say they cannot model clouds now or for the foreseeable future.

 

[Lord of Planar]

Prove it. Be specific. Cite your sources. Identify the models that leave out increases in the cooling effects due additional cloud formation. Then, explain why their models aren't off by, oh, 5º C.

It was already quoted, from the IPCC literature. They said the hold the solar heating unperturbed.

 

[Tim the plumber]

I am unfamiliar with the units used in your paste,
+1.1 (+0.9 to +1.3) W m−2 °C−1
What exactly is a "W m-2 °C−1"?

Wm[SUP]-2[/SUP] [SUP]o[/SUP]c[SUP]-1[/SUP]

W/m[SUP]2[/SUP]/[SUP]o[/SUP]c

Watts per square meter per degree c.

 

[Media_Truth]

Yes, we know that. Climate scientists know it. The IPCC knows it. The scientists developing computer models know it. And we're talking about feedbacks, not current conditions. So.... What's your point?



You can't even read an entire paragraph? Seriously?

Cloud formation processes span scales from the sub-micrometre scale
of CCN, to cloud-system scales of up to thousands of kilometres. This
range of scales is impossible to resolve with numerical simulations
on computers, and this is not expected to change in the foreseeable
future. Nonetheless progress has been made through a variety of modelling
strategies, which are outlined briefly in this section, followed by
a discussion in Section 7.2.3 of developments in representing clouds
in global models. The implications of these discussions are synthesized
in Section 7.2.3.5.

Anyway... Since you missed it, the IPCC is not only aware of the cooling that they discuss, they are also aware of the uncertainties when dealing with clouds that they discuss. Despite those uncertainties with clouds, they find that the net feedback from water vapor and lapse rate changes are extremely likely to be a net positive. If you actually read the chapter, you should see how they arrive at that conclusion.

"Read the chapter"? You can't be serious. That IPCC article has scientific terms and big words.