What is changing the climate, without the assumptions?

[longview]

Imagine if there were no history of climate science and we were trying to find
why the Earth is warming just based on the observed data?
What observed facts do we know?
The average temperatures have increased by 1.21C since the per 1900 average! (HadCrut5 to 2023)
The greenhouse gas levels have increased, causing an unknown amount of energy imbalance!
The Absorbed Solar radiation has increased by a measured 6 W m-2 since 1991 (Wild 2007)
The Outbound longwave radiation has increased by about 0.5 W m-2 since 2001, also measured (CERES)
The population of Earth has doubled since 1978!
Earth is warmer than it should be by 33C because of a 150 W m-2 energy imbalance!

Starting from here, we could say that the ratio of warming to energy imbalance is 33C/150 = 0.22 C per W m-2.
Based on that ratio the change in energy imbalance observed +6 -0.5 = 5.5 W m-2 should have caused
5.5 X 0.22 = 1.21 C of warming, which is the same as the observed warming.
There is no unknown warming to attribute to other sources like greenhouse gases.

The next question would be why has the Absorbed Solar Radiation (ASR)increased while the
Total Solar Intensity(TSI) remained unchanged?
ASR includes the incoming shortwave radiation and the shortwave reflection.
Clearing atmospheric pollution allowed more shortwave radiation in, and
Land use changes and plant growth reduced reflection.

 

[eman623]

The climate changes for a lot of reasons. Asking what percentage is due to natural cycles and what is due to human activity is absolutely a valid question IMO.

At the one extreme, I know a poster on another board who believes humanity is responsible for more than 100% of the warming! He thinks the climate would normally be in a cooling trend right now, but human CO2 emissions are enough to reverse that AND cause all of the warming we see now.

OTOH, there are deniers who claim that we have zero impact on the climate and might dispute the climate is even warming.

I don't subscribe to either extreme. Personally, I don't think anyone can answer this question definitively, and it's an unfalsifiable conjecture in any case. How would you even go about proving it? First, take two identical Earths and designate one as the control group...,

Without any hard conclusive evidence, I tend to split the climate down the middle and assume we're responsible for say half. That's enough to accept that maybe something should be done but avoids the hysteria.

Of course what should be done is a separate question, probably best left to a different thread.

 

[longview]

The climate changes for a lot of reasons. Asking what percentage is due to natural cycles and what is due to human activity is absolutely a valid question IMO.

At the one extreme, I know a poster on another board who believes humanity is responsible for more than 100% of the warming! He thinks the climate would normally be in a cooling trend right now, but human CO2 emissions are enough to reverse that AND cause all of the warming we see now.

OTOH, there are deniers who claim that we have zero impact on the climate and might dispute the climate is even warming.

I don't subscribe to either extreme. Personally, I don't think anyone can answer this question definitively, and it's an unfalsifiable conjecture in any case. How would you even go about proving it? First, take two identical Earths and designate one as the control group...,

Without any hard conclusive evidence, I tend to split the climate down the middle and assume we're responsible for say half. That's enough to accept that maybe something should be done but avoids the hysteria.

Of course what should be done is a separate question, probably best left to a different thread.

I have not seen any here who are at ether extreme.
The actual observed data is that Yes, the average temperatures have increased, and while the greenhouse gas levels have increased,
there is no scientific method to show how much warming they would cause.
What we do know is that a positive energy imbalance will cause the Earth to warm,
and we know roughly how much warming we can expect from each unit of energy imbalance measured in Watts per meter squared.
We also have actual measurements of increased Absorbed Solar radiation, that match the observed warming.
We also know that if added greenhouse gases caused an energy imbalance, that imbalance would happen
in the longwave radiation spectrum, not where we are seeing the energy imbalance!

 

[Lord of Planar]

The biggest thing I see missing is that we really do not know how much the earth has warmed either. I don't think there are any monitoring station in use that have not been influenced by the land use changes around them over time. the scientists apply corrections to the observed reading to attempt a global change, but this is an impossible task to do with any reasonable accuracy.

 

[longview]

What we know is that greenhouse gas forcing has not worked as predicted since we could monitor it!
What we do not know is if it ever worked that way.
While from a quantum perspective there is always more potential energy under the curve that could in theory cause warming, the idea of forcing on a global scale is clearly more complicated.
Think of it like attempting to dam a small stream, water just flows around any blockage, and as the level increases more paths past are available.

 

[Steve Case]

What we know is that greenhouse gas forcing has not worked as predicted since we could monitor it!
What we do not know is if it ever worked that way.
While from a quantum perspective there is always more potential energy under the curve that could in theory cause warming, the idea of forcing on a global scale is clearly more complicated.
Think of it like attempting to dam a small stream, water just flows around any blockage, and as the level increases more paths past are available.

Good analogy.

 

[Lord of Planar]

What we know is that greenhouse gas forcing has not worked as predicted since we could monitor it!
What we do not know is if it ever worked that way.

I think it is far less effective in the troposphere than they push. there is too much H2O for CO2 to matter much.

While from a quantum perspective there is always more potential energy under the curve that could in theory cause warming, the idea of forcing on a global scale is clearly more complicated.

Yep. And impossible to actually measure the effects of only one variable in a mix of so many.

Think of it like attempting to dam a small stream, water just flows around any blockage, and as the level increases more paths past are available.

This is how I see wind power. Wind power will no doubt alter wind paths. We are also taking energy out of the wind and reducing it. The question is, how significantly does it do these things? Is it enough to matter?

 

[longview]

I think it is far less effective in the troposphere than they push. there is too much H2O for CO2 to matter much.

Yep. And impossible to actually measure the effects of only one variable in a mix of so many.

This is how I see wind power. Wind power will no doubt alter wind paths. We are also taking energy out of the wind and reducing it. The question is, how significantly does it do these things? Is it enough to matter?

When the net effect is below zero, i.e. negative forcing in the longwave spectrum, I am not sure any of the rest of the details matter.
Lowering CO2 emissions may make people "feel" like they are doing something, but it will not change how the climate is changing.

 

[longview]

Good analogy.

I was thinking about this and something occurred to me, as the temperature gets warmer the central band of the Planck radiation
moves to shorter wavelengths. The shorter wavelengths have a different spectral response.
I thought about the temperature range on this and assumed that for the vast majority of the time
the temperature of Earth exists between -40 C and +40 C (-40F to +104F).
I know it gets warmer and colder, but this covers more than 99.9% of the time.
In terms of the central band of Planck radiation, this means that the center moves from 12.43 um down to 1 um.
So the only time Earth's Planck radiation is at the center of CO2's band (15 um) is when it is below -40C.
Almost all the Planck radiation from Earth, is between 1 and 12 um, with our average temperature of 15 C being about 10 um.

 

[PoS]

Imagine if there were no history of climate science and we were trying to find
why the Earth is warming just based on the observed data?
What observed facts do we know?
The average temperatures have increased by 1.21C since the per 1900 average! (HadCrut5 to 2023)
The greenhouse gas levels have increased, causing an unknown amount of energy imbalance!
The Absorbed Solar radiation has increased by a measured 6 W m-2 since 1991 (Wild 2007)
The Outbound longwave radiation has increased by about 0.5 W m-2 since 2001, also measured (CERES)
The population of Earth has doubled since 1978!
Earth is warmer than it should be by 33C because of a 150 W m-2 energy imbalance!

Starting from here, we could say that the ratio of warming to energy imbalance is 33C/150 = 0.22 C per W m-2.
Based on that ratio the change in energy imbalance observed +6 -0.5 = 5.5 W m-2 should have caused
5.5 X 0.22 = 1.21 C of warming, which is the same as the observed warming.
There is no unknown warming to attribute to other sources like greenhouse gases.

The next question would be why has the Absorbed Solar Radiation (ASR)increased while the
Total Solar Intensity(TSI) remained unchanged?
ASR includes the incoming shortwave radiation and the shortwave reflection.
Clearing atmospheric pollution allowed more shortwave radiation in, and
Land use changes and plant growth reduced reflection.

 

[Gardener]

Books about the coming ice age were quite the rage 50 years go.

 

[longview]

Books about the coming ice age were quite the rage 50 years go.

Yes and we identified the correct problem (Aerosol emissions dimming the sunlight) and corrected it.
As it turns out, it was a bit of an overcorrection, and now we are tracking the natural warming.
The difference is that we released centuries of slow natural warming, in just decades.
The natural warming would be like the black line, what we got was the blue line, but I did not show that it was actually negative.
The measured slope on the blue line was actually much greater, recorded in peer review as 6 W m-2 between 1992 and 2001.
From Dimming to Brightening: Decadal Changes in Solar Radiation at Earth’s Surface

 

[CLAX1911]

Imagine if there were no history of climate science and we were trying to find
why the Earth is warming just based on the observed data?

If there was no history how would we know it was warning?

I would argue the same thing that caused it to change for the past 5 billion years.

As to what's causing it I'd speculate solar cycles, magnetic field changing.

What observed facts do we know?
The average temperatures have increased by 1.21C since the per 1900 average! (HadCrut5 to 2023)
The greenhouse gas levels have increased, causing an unknown amount of energy imbalance!
The Absorbed Solar radiation has increased by a measured 6 W m-2 since 1991 (Wild 2007)
The Outbound longwave radiation has increased by about 0.5 W m-2 since 2001, also measured (CERES)
The population of Earth has doubled since 1978!
Earth is warmer than it should be by 33C because of a 150 W m-2 energy imbalance!

Starting from here, we could say that the ratio of warming to energy imbalance is 33C/150 = 0.22 C per W m-2.
Based on that ratio the change in energy imbalance observed +6 -0.5 = 5.5 W m-2 should have caused
5.5 X 0.22 = 1.21 C of warming, which is the same as the observed warming.
There is no unknown warming to attribute to other sources like greenhouse gases.

The next question would be why has the Absorbed Solar Radiation (ASR)increased while the
Total Solar Intensity(TSI) remained unchanged?
ASR includes the incoming shortwave radiation and the shortwave reflection.
Clearing atmospheric pollution allowed more shortwave radiation in, and
Land use changes and plant growth reduced reflection.

 

[longview]

If there was no history how would we know it was warning?

I would argue the same thing that caused it to change for the past 5 billion years.

As to what's causing it I'd speculate solar cycles, magnetic field changing.

We would know it is warming because crops can grow in places they could not before.

 

[MAGAnificent]

OTOH, there are deniers who claim that we have zero impact on the climate and might dispute the climate is even warming.

I don't subscribe to either extreme. Personally, I don't think anyone can answer this question definitively, and it's an unfalsifiable conjecture in any case. How would you even go about proving it? First, take two identical Earths and designate one as the control group...,

Without any hard conclusive evidence, I tend to split the climate down the middle and assume we're responsible for say half. That's enough to accept that maybe something should be done but avoids the hysteria.

To be fair. there is no evidence that anything man has done has had any permanent effects on the climate. We can affect current patterns for instance creating heat islands with concrete jungles in our biggest cities. And cleaning up the air pollution is places like Los Angeles will actually result regionally in more heat. As for "something should be done". Absolutely. We should cut pollution for the sake of clean air and clean water, not chicken little climate hysteria.

 

[CLAX1911]

We would know it is warming because crops can grow in places they could not before.

And how would you know that this was a trend or a global trend that wouldn't fluctuate if you didn't see that it has a before?

 

[longview]

And how would you know that this was a trend or a global trend that wouldn't fluctuate if you didn't see that it has a before?

You would not know if it was a cycle or something new, except that most things have a cycle!

 

[CLAX1911]

You would not know if it was a cycle or something new, except that most things have a cycle!

Yeah so any reaction would be some random shot in the dark

Acting without knowledge which is really what we're doing now is never wise.

 

[longview]

Yeah so any reaction would be some random shot in the dark

Acting without knowledge which is really what we're doing now is never wise.

We know that we have some very real problems,
like sustainable energy and fresh water, but that is not a control factor.

 

[CLAX1911]

We know that we have some very real problems,

Do we? It seems only really greedy and power hungry people seem to think so and they seem to completely ignore the problem probably because it's in a country that doesn't have a lot of disposable income.

Interesting coincidence huh?

like sustainable energy and fresh water, but that is not a control factor.

so develop religious devotion by scaring school children into believing they will have nowhere to live when they grow up.

 

[Steve Case]

I was thinking about this and something occurred to me, as the temperature gets warmer the central band of the Planck radiation
moves to shorter wavelengths. The shorter wavelengths have a different spectral response.
I thought about the temperature range on this and assumed that for the vast majority of the time
the temperature of Earth exists between -40 C and +40 C (-40F to +104F).
I know it gets warmer and colder, but this covers more than 99.9% of the time.
In terms of the central band of Planck radiation, this means that the center moves from 12.43 um down to 1 um.
So the only time Earth's Planck radiation is at the center of CO2's band (15 um) is when it is below -40C.
Almost all the Planck radiation from Earth, is between 1 and 12 um, with our average temperature of 15 C being about 10 um.

A black body that radiates predominately at ~15µ would be a brick of dry ice.

 

[Lord of Planar]

A black body that radiates predominately at ~15µ would be a brick of dry ice.

And here is the longwave emission at 190 K.

 

[longview]

And here is the longwave emission at 190 K.

View attachment 67540087

The idea that the center wavelength of longwave emissivity changes as we cycle through the day,
and mostly is in wavelengths shorter than 15 um, makes for a very complex problem.
The transparent portions of the atmospheric window, would be cycled past each day.

 

[Steve Case]

There's some agreement* that Climate sensitivity
per doubling of CO2 sans feedbacks is ~1.2°C

WattsUpWithThat
Tom Halla 1.2 C
Rud Istvan 1.3C. & 1.2C Lindzen
Steve Case James Hansen 1.2
Sparta Nova 4 much, much lower than 1.2 C.

William Happer 0.75C Rasool & Schneider 1971

There are others that say around one degree Celsius

*Science isn't a popularity contest, so just because
four out of six and some others say 1.2C and only
two say 0.75C or lower doesn't mean 1.2C is correct.

 

[Lord of Planar]

There's some agreement* that Climate sensitivity
per doubling of CO2 sans feedbacks is ~1.2°C

WattsUpWithThat
Tom Halla 1.2 C
Rud Istvan 1.3C. & 1.2C Lindzen
Steve Case James Hansen 1.2
Sparta Nova 4 much, much lower than 1.2 C.

William Happer 0.75C Rasool & Schneider 1971

There are others that say around one degree Celsius

*Science isn't a popularity contest, so just because
four out of six and some others say 1.2C and only
two say 0.75C or lower doesn't mean 1.2C is correct.

Until someone shows me why I should change my mind, I am going with 0.5 degrees.