climate change / unpredictable weather/wind

[Matteo V]

For me if you forecast say 5C change and instead get 1 or 2C that is not a very good model.

Sorry to use a quote from you to explain the issue that others are having here, but it simplifies things a bit.

First off, what question did you ask the model to answer above? - it appears that you simply asked if the climate was changing.

But the issue here is one of warming vs cooling. So let's see if the model can predict one or the other. But, alas, it sometimes predicts warming, and sometimes predicts cooling.

How does it do this? Well first, there is a vast number of initial condition inputs. They are made up of things like atmospheric temps at different altitudes, ocean temps, ocean currents, ground reflectivity, and too many more to list. All of those initial condition inputs have a margin of error (ex. 1.2c avg with 1.1c to 1.3c margin of error).

Next, you have the "weight" of those known variables, and the known margin of error for that "weight". And even now, among climate change enthusiast scientists, the actual "weight" of c02 is still being revised down.

Then you get into the dynamics of the running model. Questions like if ocean cooling does occur locally or globally, is the rate of ocean c02 uptake linear? - which leads to hundreds of other questions that cannot be answered. So in place of answers, assumptions are put in place. For each assumption, a substitute assumption is also available to be run in the model.

On top of that, some runs of the model with different margin of errors inputs, weights to variables, and assumptions, show inconsistencies pointing toward missing variables. And when some of these variables are discovered, their inclusion in the model points toward more missing variables.


All along, the predictions of the evolving model not only produce both warming and cooling, but can be MADE to show one or the other by adjusting variables within the margin of error.

So, how much value do you really give to a bunch of politicians, politically/emotionally motivated scientists, and pushers of propaganda, telling you they are certain of the course of the climate from our current modeling capabilities? Especially, when logic dictates that a warming climate is tolerable, but a cooling climate is famine, death, WW3, and actual mass extinction.

[Havre]

The implication being these propaganda pushers wish for famine, WW3 etc? I wouldn't say there is a difference in the morality of either side here. There are "denyers" that probably deny mostly because they are lazy - it is the easiest solution. There are "denyers" that think it would be wrong to deny billions of humans access to cheap energy even if it also have some downsides. There are "advocates" that honestly fear we are ruining the planet. The same way there are "advocates" that finally found a way of pushing their wide scale social changes by using climate change as the reason for doing so. Not to mention that it isn't true that all this "pushers" are young girls, politicians etc. However those are the ones BBC focus on.

I'm not sure if logic dictates one or the other. There is nothing inherently illogical about thinking there is a tipping point for nature where we do not understand the full scope of the consequences if it warms too quickly. And as you would argue we wouldn't know how to model those consequences anyway.

As for modeling I don't know. It might be one of these chess situations where you first think it is complex, but not so complex that you can't come up with a model that gives fairly reasonable results. Later you realize we are years and years maybe hundred of years away before we really understand earth's climate. There is nothing wrong in principle having parts of the model being controlled by unknown factors though. A model doesn't have to be completely understood to give good predictions. A bit of a problem when it doesn't of course. And it is pretty annoying how the results of this predictions are communicated to the public. In guess it says something about the trust they have in the public - pretending that these results are "facts" as slide calls them.

[slide]

it was david Attenborough's blue planet series , that first alerted the world about the plastic problem in our seas , another fact for you climate change friends

[SimonP]

You can't make a judgement on how well climate models work until you understand how they work. This is a good article that came up on my newsfeed this morning. Zeke Hausfather is probably the foremost expert in climate modelling. You have to look at multiple lines of evidence to determine what is likely. In summary, the mean equlibrium sensitivity is 3.0° Celsius per doubling of CO2 with the probable limits of error between 1.8 and 4.6°C.
https://thebreakthrough.org/issues/ener ... hot-models

[foilholio]

You can't make a judgement on how well climate models work until you understand how they work.

Sure it would help but no. If the weather forecast keeps telling me it will rain tomorrow and it never does do I need to know how he made that prediction to judge it? I would say you can't keep making illogical statements but hey you keep doing it. You can't also either stick to a point or answer simple questions like, for the fiftieth time, What is climate an average of?

with the probable limits of error between 1.8 and 4.6°C

So 0.8C over 100 years is a lot but a 2.8C or 255% variance in predication is perfectly fine. If you ask me it would seem politicians have become the scientist, because that is a lot of ass covering there. The CCP would be proud with no face to be lost.

[SimonP]

Weather is not climate. Climate is the description of the long-term pattern of weather in a particular area, i.e. climate is the average pattern of weather for a particular region.
When scientists talk about climate, they're looking at averages of precipitation, temperature, humidity, sunshine, wind velocity, phenomena such as fog, frost, and hail storms, and other measures of the weather that occur over a long period in a particular place.
https://www.nasa.gov/mission_pages/noaa ... ather.html

High resolution weather models do a good job of predicting total rainfall but there can be significant localised variation, especially with thunderstorms.
You also don't seem to understand probability distributions. Climate sensitivity is much more likely to be clustered around the mean rather than two standard deviations out. It is almost certain that the ECS does not fall outside of those bounds.
Global temperatures will continue to rise until long lifetime greenhouse gas emissions are reduced to zero. This is indisputable.

[slide]

a fact for my new climate change friend , mr T......it is 8 degrees warmer in the artic today than in the warmest part of the uk

20.75

[Pemba]

You can't make a judgement on how well climate models work until you understand how they work.

Sure it would help but no. If the weather forecast keeps telling me it will rain tomorrow and it never does do I need to know how he made that prediction to judge it? I would say you can't keep making illogical statements but hey you keep doing it. You can't also either stick to a point or answer simple questions like, for the fiftieth time, What is climate an average of?

with the probable limits of error between 1.8 and 4.6°C

So 0.8C over 100 years is a lot but a 2.8C or 255% variance in predication is perfectly fine. If you ask me it would seem politicians have become the scientist, because that is a lot of ass covering there. The CCP would be proud with no face to be lost.

Whats your point here ? Are you really looking for a definition of climate ? To prove he didn't define climate in the best way ? Lots of questions don't get answered here. Be a man about it or something. The variance in prediction is what it is. Fine or not is just an opinion about it. Question is what would (at least) 1.8 degree warming (relative to when?) do and where are we now on the CO2 doubling (relative to when?).

[Pemba]

High resolution weather models do a good job of predicting total rainfall but there can be significant localised variation, especially with thunderstorms.
You also don't seem to understand probability distributions. Climate sensitivity is much more likely to be clustered around the mean rather than two standard deviations out. It is almost certain that the ECS does not fall outside of those bounds.
Global temperatures will continue to rise until long lifetime greenhouse gas emissions are reduced to zero. This is indisputable.

I'm really glad somebody finally mentions probability. So according to the latest CMIP6 models there is an estimated 66% chance that Equilibrium Climate Sensitivity (ECS) lies between 1.8 and 5.6 degrees Celsius. This is what I conclude from the description of the first graph in the article you referred to - please correct me if I have misinterpreted. I find that a low degree of certainty and I wonder why they used 66%. Looking a bit further I note that 66% is exactly the limit that allows the publishers to use the word "likely" (had it been 65% it would have been "about as likely as not"). I wonder what the range would be for a "very likely" (>90% probability) scenario. Do you happen to know what the reference points with regards to CO2 doubling and temperature are and where we are now (I know - I can find out myself with a bit of effort) ?

[foilholio]

The reference point for CO2 doubling is not needed as you can take any point and then you need to double it to get the same warming as if you doubled it before. So the warming from 200ppm to 400ppm is the same as 400ppm to 800ppm or from 800ppm to 1600ppm. This ignores other factors like all the ice melting which will warm the planet more as well.

Global temperatures will continue to rise until long lifetime greenhouse gas emissions are reduced to zero. This is indisputable.

Well no. It has not been proven that CO2 is the sole driver of climate change so if as it likely is not then temperatures could drop or pause while CO2 levels still increase, especially given the diminishing effect of more CO2. Also given higher CO2 levels and higher temps the bio mass of the planet will as it has already increase putting more downward pressure on CO2 levels.

You also don't seem to understand probability distributions

It is a fancy way of having a wide range of guesses. It is not prediction if you are guessing. Why not just state a single number as your guess and accept being wrong by some margin?
Oh that's right academic culture really really doesn't like when you make mistakes.

Weather is not climate

Weather is climate if it is representative of the climate. That means not extreme events. Like extreme events as used as representations for climate change.

Question is what would (at least) 1.8 degree warming (relative to when?) do and where are we now on the CO2 doubling (relative to when?).

Well if you know the distribution of that change then you can look at how similar climates are or have been to make a guess. With most of the temperature increase predicted to arrive in colder regions it will make them much more habitable for life. Strangely to those pushing the alarm narrative life does not do well in heavy ice and extreme cold. The seemingly most abundant periods in Earths history have been a lot warmer and had a lot more CO2.