Yet more proof.

[BeElBeeBub]

This evidence is selective.  Why 1991 to 2020?  That's not a true average.

The met uses 30 year blocks as the average.  That's just how it is. If you want to use a different block as your baseline you can but that just makes the April look even warmer by comparison.

For example the April averages for Kew Gardens (picked as random London location)

(period, maxC, minC)
91-20, 15.13C, 5.10C
81-10, 14.42C, 4.72C
71-00, 13.59C, 4.43C
61-90, 13.33C, 4.30C

https://www.metoffice.gov.uk/research/climate/maps-and-data/uk-climate-averages/gcpuckhb6

April (and May) were unusually warm, even if they felt crap.

[Scott777]

March 2024 from met office - slightly warmer than average (which is still not that warm given it's march) and wet

April 2024 from met office - wet and warmer than average

This evidence is selective.  Why 1991 to 2020?  That's not a true average.

[BeElBeeBub]

No you haven't. You have built a model that is designed to show the fire started by fireworks, what a shock when you run the program it shows the fire started by fireworks. That's how fundamentally flawed the models are.

You keep telling me I've said xyz can't have happened, this is total fabrication, I've never said anything of the kind. I've said CO2 has never driven temperature increases in the last 600 million years, are you denying that this has never happened before?

The models are built from 1st principles. We have solid theoretical and experimental evidence that CO2 concentrations in the atmosphere affect the amount of energy radiated into space. The models don't presuppose anything, the warming effect falls out of the interactions when models.

Maybe we are at cross purposes.

You say co2 has never *driven* temperature changes before (eg ends of ice ages). Do you mean driven or initiated?

You yourself said warming can release Co2.

So we have an ice age. A cold frozen earth, glaciers over London etc. all is calm, all is bright and so on.

Then a small upward nudge (say increased solar radiation) can nudge the temperature up, which releases co2 from oceans raising the atmospheric concentration. This increases the greenhouse effect and more warming happens which release more co2, the planet warms more and then ice age ends.

This has happened before. The extra energy from the millennia long solar/orbital cycles is not enough to account for the warming we see in the records.  But a feedback mechanism using co2 greenhouse warming as you described does account for the extra warming 

So the co2 didn't initiate the warming (that was the solar cycle) but it did drive the warming.

Now this time round, we are providing that initial push to increase the co2 concentrations.  The same mechanism (greenhouse effect) is happening but this time we are the initiator rather than oceans warming due to increased solar radiation.

[Nick]

I'm saying we have a fire and we have traced it's source back to a gender reveal party where the fireworks went wrong.

We can see the fire.  We can show that putting very hot things next to dry grass can cause a fire and we have TiK Tok videos of someone setting off fireworks in the dry grass.

Our hypothesis is that these fireworks caused the forest fires and we should stop setting off fireworks in dry grass.

You are saying that humans can't be the cause because forest fires have happened naturally long before humans were around

(Edit)

I'm saying there's good evidence that *this time* the fire is caused by humans and we should make changes to stop things getting worse.

No you haven't. You have built a model that is designed to show the fire started by fireworks, what a shock when you run the program it shows the fire started by fireworks. That's how fundamentally flawed the models are.

You keep telling me I've said xyz can't have happened, this is total fabrication, I've never said anything of the kind. I've said CO2 has never driven temperature increases in the last 600 million years, are you denying that this has never happened before?

[BeElBeeBub]

Sorry but you've got that totally the wrong way round. You're the one saying that the fire is definitely caused by humans without any proof. You have a model that has oxygen and fuel and the code says if we add CO2 we will have a fire. Amazing that when you add CO2 to your model it shows there will be fire 🔥 SHOCKER!!

I'm saying we have a fire and we have traced it's source back to a gender reveal party where the fireworks went wrong.

We can see the fire.  We can show that putting very hot things next to dry grass can cause a fire and we have TiK Tok videos of someone setting off fireworks in the dry grass.

Our hypothesis is that these fireworks caused the forest fires and we should stop setting off fireworks in dry grass.

You are saying that humans can't be the cause because forest fires have happened naturally long before humans were around

(Edit)

I'm saying there's good evidence that *this time* the fire is caused by humans and we should make changes to stop things getting worse.

[BeElBeeBub]

Well the people building the models must have totally ignored the fact that for 600 million years CO2 lagged temperature by 750 years. They also have the rate of warming on average 43% faster than has actually occurred since the 1970's.

So I'll ask again, since CO2 has lagged temperature for the last 600 million years, how do models have CO2 driving temperature if it's not for ulterior motives?

No the people building the models are acutely aware of the climate history.

Your figure of 43% probably comes from this report

https://www.heritage.org/environment/report/global-warming-observations-vs-climate-models

It doesn't really show it's working but it does have this graph as a centre piece.



The problem with this is it doesn't really show where it gets the models average from (or how it gets them).

What we can see is that the observed rise (blue) goes from -0.4C to +0.4C over the period 1979 to 2022. That's about 0.2C per decade.

If we look at what the IPCC reports over the years it matches fairly well.

1995 report gives +2C by 2100 (just under 0.2C decade)

2007 report gives 0.2C per decade (with a lot of variability depending on how emissions go)

2014 report gives a much wider range (again dependnt on emissions reduction path) - ranging from 0.14C to 0.3C per decade. The worst case of we do very little has it at 0.48C per decade

So it seems that the IPCC report has been fairly on the money with regards to the rise.

If you want to create your own climate model that assumes CO2 isn't a.driver then you are welcome.

But it must be a physics based model and  you need to be able to pass the hindcast test.

If you can show that cosmic rays or space dust or volcanoes are sufficient to cause the warming we have observed that will be massive and you will win a (richly deserved) nobel prize.

[Nick]

No I am not saying that

As has been agreed, the plant has warmed and cooled may times in the past, well before any human influence. That is not in any doubt

What you are doing is looking at a forest fire and saying "there is no way this was caused by humans, because forest fires have been happening for millions of years before humans".

Sorry but you've got that totally the wrong way round. You're the one saying that the fire is definitely caused by humans without any proof. You have a model that has oxygen and fuel and the code says if we add CO2 we will have a fire. Amazing that when you add CO2 to your model it shows there will be fire 🔥 SHOCKER!!

[Nick]

you took the passage about overestimating co2 concentrations out of context.  CO2 concentrations are (mostly) an input into the model. They don't have a bearing on the accuracy of the model itself.

The study you took the passage from, an extensive study of many models used over 50 years, concluded that the models were pretty good at predicting what happens in the years after they were published.  The exact opposite of your position.

They used atmospheric models which are based on physics theory and then checked against real world measurements.

Do you understand how models are built and tested?

They are first principle models. They create a physics based model of the world, using thermodynamics, fluid dynamics, electromagnetic theory etc.

They then validate it by sticking in real world (as best we can fathom) starting conditions (let's say the climate etc 100mn years ago) then running it forward to see how it's predictions match what actually happened.

So they have to account for all the cycles in the past you have pointed out.

Once they have passed that validation they are enter today's conditions and what we expect things like co2 emissions to be (from government policies etc).  They then run forward to see what the model, that has already predicted past events to a certain level of accuracy, predicts for our future.

What they are not are dumb extrapolations of the temperature and co2 graphs from times past.

Well the people building the models must have totally ignored the fact that for 600 million years CO2 lagged temperature by 750 years. They also have the rate of warming on average 43% faster than has actually occurred since the 1970's. 

So I'll ask again, since CO2 has lagged temperature for the last 600 million years, how do models have CO2 driving temperature if it's not for ulterior motives?

[BeElBeeBub]

Are you telling me that none of these phenomena have ever happened before fossil fuels were being burnt? Cause your link from NASA suggests otherwise.

No I am not saying that 

As has been agreed, the plant has warmed and cooled may times in the past, well before any human influence. That is not in any doubt

What you are doing is looking at a forest fire and saying "there is no way this was caused by humans, because forest fires have been happening for millions of years before humans".

[BeElBeeBub]

Your pomposity shows no bounds: who are you to tell me what I misunderstand?

.

you took the passage about overestimating co2 concentrations out of context.  CO2 concentrations are (mostly) an input into the model. They don't have a bearing on the accuracy of the model itself.

The study you took the passage from, an extensive study of many models used over 50 years, concluded that the models were pretty good at predicting what happens in the years after they were published.  The exact opposite of your position.

Answer this.

How does a climate model know that increasing CO2 increases Temperature.

They used atmospheric models which are based on physics theory and then checked against real world measurements.

Do you understand how models are built and tested?

They are first principle models. They create a physics based model of the world, using thermodynamics, fluid dynamics, electromagnetic theory etc.

They then validate it by sticking in real world (as best we can fathom) starting conditions (let's say the climate etc 100mn years ago) then running it forward to see how it's predictions match what actually happened.

So they have to account for all the cycles in the past you have pointed out.

Once they have passed that validation they are enter today's conditions and what we expect things like co2 emissions to be (from government policies etc).  They then run forward to see what the model, that has already predicted past events to a certain level of accuracy, predicts for our future.

What they are not are dumb extrapolations of the temperature and co2 graphs from times past.

[BeElBeeBub]

It's BS.  In London, March and April was bloody cold.  I want to see evidence of your claim.

March 2024 from met office - slightly warmer than average (which is still not that warm given it's march) and wet

https://www.metoffice.gov.uk/binaries/content/assets/metofficegovuk/pdf/weather/learn-about/uk-past-events/summaries/mwr_2024_03_for_print.pdf

April 2024 from met office - wet and warmer than average

https://www.metoffice.gov.uk/binaries/content/assets/metofficegovuk/pdf/weather/learn-about/uk-past-events/summaries/mwr_2024_04_for_print.pdf

crucially this was driven by higher than expected minimum temps (IE nights) whilst day temps were about as expected. This probably explains why most people thought it was no warmer than normal as they aren't typically out at night and if they do the difference between 5C and 7C isn't that noticeable - both are wrap up warm weather.
Both months were also much duller than normal which contributed to the feeling they were cold.

[Nick]

You didn't cite any source for your screen grab but it does appear as the first item when you search for "how inaccurate are climate change models?"
(This link may change over time)

https://www.google.com/search?q=how+inaccurate+are+climate+change+models

If you follow to the study it quotes from

https://eps.harvard.edu/files/eps/files/hausfather_2020_evaluating_historical_gmst_projections.pdf

You will find you have quotes out of context and misunderstood.

The full para saysThat is to say the people running the models input future (to them in the 70's and 80') co2 emissions that were higher than they subsequently turned out to be - partially because we took action to reduce the growth in emissions.

The study you cite concludes.....
Ie the study you cite to support your argument says exactly the opposite of what you argued.

This is fairly typical of how you have debated this (and other) topics. You have Google searched (or other means) for the first bit of evidence that appears to confirm your position, not looked at it in depth or context, and just threw it up as "ha! See!".

Your pomposity shows no bounds: who are you to tell me what I misunderstand?

Answer this. 

How does a climate model know that increasing CO2 increases Temperature. 

[Scott777]

And every month since December has been above average.

It's BS.  In London, March and April was bloody cold.  Right now, it is cold and wet.  It was the same in Norfolk where I visited.  I want to see evidence of your claim.

[Nick]

The 3 things are

CO2 increasing - I think we both agree this is a real measurement.

Temperature increasing - again I think we both agree this is a real measurement

Finally, and crucially, we have direct measurements the energy leaving the earth is falling and it is falling in the bands we would expect for co2 and other gasses.

These are all measurements - no climate models were involved.

Separately we have estimates of energy imbalance from ocean temperature measurements which tally with the measurements from space

https://www.nasa.gov/centers-and-facilities/langley/joint-nasa-noaa-study-finds-earths-energy-imbalance-has-doubled/

Again, this has nothing to do with climate models.

So we have 4 bits of direct, contemporary evidence pointing towards CO2etc reducing outgoings radiation and this heating the planet.

We have experimental and theoretical evidence as to why CO2 can trap heat in the atmosphere and cause global warming.

All you have an assertion that CO2 cannot drive temperature.  You don't have any explanation as to why that might be the case beyond "nature wouldn't allow that".

I will now touch in your citation and why it speaks volumes about your approach

Are you telling me that none of these phenomena have ever happened before fossil fuels were being burnt? Cause your link from NASA suggests otherwise. 


From your link. 

"The study finds that the doubling of the imbalance is partially the result an increase in greenhouse gases due to human activity, also known as anthropogenic forcing, along with increases in water vapor are trapping more outgoing longwave radiation, further contributing to Earth's energy imbalance. Additionally, the related decrease in clouds and sea ice lead to more absorption of solar energy.

The researchers also found that a flip of the Pacific Decadal Oscillation (PDO) from a cool phase to a warm phase likely played a major role in the intensification of the energy imbalance. "

[BeElBeeBub]

Right, so you have 3 things, models, increase in temperature and increase in CO2.

Most climatologists agree the models are wrong, they have that much fudge in them to try and make them mimic actuality, they could open a sweet shop.

Secondly, we know temperature is going up and we know CO2 is going up. Where is your science to show the relationship? For the last 600 million years Temperature has driven CO2, and the atmospheric warming is also in the wrong place.

You didn't cite any source for your screen grab but it does appear as the first item when you search for "how inaccurate are climate change models?"
(This link may change over time)

https://www.google.com/search?q=how+inaccurate+are+climate+change+models

If you follow to the study it quotes from

https://eps.harvard.edu/files/eps/files/hausfather_2020_evaluating_historical_gmst_projections.pdf

You will find you have quotes out of context and misunderstood.

The full para says

A number of model projections had external forcings that poorly matched observational estimates due to the exclusion of non‐CO2 forcing agents. However, all models included projected future CO2 concentrations, providing a common metric for comparison, and these are shown in Figure S4. Most of the historical climate model projections overestimated future CO2 concentrations, some by as much as 40 ppm over current levels, with projected CO2 concentrations increasing up to twice as fast as actually observed (Meinshausen, 2017). Of the 1970s climate model projections, only Mi70 projected atmospheric CO2 growth in‐line with observa­tions. Many 1980s projections similarly overestimated CO2, with only the Hansen 88 Scenarios A and B pro­jections close to observed concentrations.

That is to say the people running the models input future (to them in the 70's and 80') co2 emissions that were higher than they subsequently turned out to be - partially because we took action to reduce the growth in emissions.

The study you cite concludes.....

RESEARCH LETTER 10.1029/2019GL085378 Key Points: • Evaluation of uninitialized multidecadal climate model future projection performance provides a concrete test of model skill • The quasi‐linear relationship between model/observed forcings and temperature change is used to control for errors in projected forcing • Model simulations published between 1970 and 2007 were skillful in projecting future global mean surface warming Supporting Information: • Supporting Information S1 Correspondence to: Z. Hausfather, hausfath@gmail.com Citation: Hausfather, Z., Drake, H. F., Abbott, T., & Schmidt, G. A. (2020). Evaluating the performance of past climate model projections. Geophysical Research Letters, 47, e2019GL085378. https://doi. org/10.1029/2019GL085378 Received 16 SEP 2019 Accepted 26 NOV 2019 Accepted article online 4 DEC 2019 Evaluating the Performance of Past Climate Model Projections Zeke Hausfather1 2,3 3 , and Gavin A. Schmidt4 1Energy and Resources Group, University of California, Berkeley, CA, USA, 2Massachusetts Institute of Technology/Woods Hole Oceanographic Institution Joint Program in Oceanography, Woods Hole, MA, USA, 3Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA, 4NASA Goddard Institute for Space Studies, Broadway, NY, USA Abstract Retrospectively comparing future model projections to observations provides a robust and independent test of model skill. Here we analyze the performance of climate models published between 1970 and 2007 in projecting future global mean surface temperature (GMST) changes. Models are compared to observations based on both the change in GMST over time and the change in GMST over the change in external forcing. The latter approach accounts for mismatches in model forcings, a potential source of error in model projections independent of the accuracy of model physics. We find that climate models published over the past five decades were skillful in predicting subsequent GMST changes, with most models examined showing warming consistent with observations, particularly when mismatches between model‐projected and observationally estimated forcings were taken into account. Plain Language Summary Climate models provide an important way to understand future changes in the Earth's climate. In this paper we undertake a thorough evaluation of the performance of various climate models published between the early 1970s and the late 2000s. Specifically, we look at how well models project global warming in the years after they were published by comparing them to observed temperature changes. Model projections rely on two things to accurately match observations: accurate modeling of climate physics and accurate assumptions around future emissions of CO2 and other factors affecting the climate. The best physics‐based model will still be inaccurate if it is driven by future changes in emissions that differ from reality. To account for this, we look at how the relationship between temperature and atmospheric CO2 (and other climate drivers) differs between models and observations. We find that climate models published over the past five decades were generally quite accurate in predicting global warming in the years after publication, particularly when accounting for differences between modeled and actual changes in atmospheric CO2 and other climate drivers. This research should help resolve public confusion around the performance of past climate modeling efforts and increases our confidence that models are accurately projecting global warming.

Ie the study you cite to support your argument says exactly the opposite of what you argued.

This is fairly typical of how you have debated this (and other) topics. You have Google searched (or other means) for the first bit of evidence that appears to confirm your position, not looked at it in depth or context, and just threw it up as "ha! See!".