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> And even now the science is clearly biased - what does the field do, for example, when there is consistent evidence that it's predictions are far too warm? They go digging for explanations like oceanic absorption, rather than adjust their models.

I was in academia and reading the literature as this kerfuffle went down (2012, IIRC). The models of temperature overshot, but the models of global heat flow did not, so the net effect of the misprediction was always going to be a delay rather than a change in the ultimate effect. To use the hydraulic analogy, we could see water flowing into the barrel at the same rate (satellites can measure total heat influx / outflux from Earth very accurately) but the barrel's rising water level slowed down in an unanticipated manner. They eventually tracked it down to oceanic mixing. In the hydraulic analogy, the barrel got wider below where we expected it to get wider. The water is still pouring in, though, and it doesn't change the fact that the water level in the barrel is rising.

Academia treated the matter with the utmost professionalism. The journal articles minced no words about the models that had failed and the implications, limited as they were.

Liberal media didn't report it at all. Bias? Sure, a little.

Conservative media sang the temperature models' failure from the rooftops, ignored the success of the heat models, and jumped to the conclusions that global warming as a theory was in doubt and that scientists had biased the results. The conservative media's bias was the worst of the three, by my reckoning.

> They go digging for explanations like oceanic absorption, rather than adjust their models.

Isn't oceanic absorption experimentally verified? So they did adjust their models correctly -- the correct way was to model oceanic absorption.

How else do you adjust models if not by finding processes previously not modeled, verify them and then model them?

>Isn't oceanic absorption experimentally verified

You cannot experimentally verify oceanic heat absorption, the same way you cannot experimentally verify anything predicted by climate science - because the scale of such experiments make them effectively impossible.

At best you can experimentally verify bits of theory on small scales - say, testing the temperature of a greenhouse with varying levels of CO2 - then combine those bits into a predictive mathematical/computational model, make predictions, and then perform measurements on the planet and look for results within a confidence interval.

But you're taking a problem with a massive number of degrees of freedom and attempting to reduce the search space to a few dozen. This reduction is non-unique, which is to say there are a large number of ways to model a complex phenomenon like climate which will agree with past and present measurements, but fail to account for the actual drivers which will influence the future.

This is partly why all climate models to date have been incorrect, and the fact that they consistently overpredict temperatures is a strong indication of institutional bias.

>How else do you adjust models if not by finding processes previously not modeled, verify them and then model them?

Excluding potential bias from researchers, there's nothing particularly wrong with this approach, it's the best we can do and given enough time and resources eventually such a search should theoretically stumble upon a correct, complete model, though this isn't necessarily practically achievable for many real world problems. But the issue here is that the confidence of such results should not be misrepresented, and that's the part that people who claim the "science is settled" are missing.

Here is an article describing mechanism of oceanic heat absorption (something to do with changing gradient of surface layer exposed to infrared radiation affecting heat exchange) and referencing multiple studies that indicate oceans do heat up [0].

"Observations of ocean temperatures have revealed that the ocean heat content has been increasing significantly over recent decades (Willis et al, 2004; Levitus et al, 2005; Lyman et al, 2006)"

[0] http://www.realclimate.org/index.php/archives/2006/09/why-gr...

> Excluding potential bias from researchers [...]

That's a good point. There is a potential for motivated reasoning bias, when you scrutinize evidence you don't like more, and stop scrutinizing evidence you do like earlier. But in this case effect is measured, verified and explained (as far as I can tell). And it makes models more precise.

Is it possible that people looked too hard for negative feedback loops instead of looking for faults in already modeled processes? Maybe. But they did find such a loop and explained discrepancy. Now you need another discrepancy between model prediction and incoming data to see if anything needs adjusting.

> You cannot experimentally verify oceanic heat absorption, the same way you cannot experimentally verify anything predicted by climate science - because the scale of such experiments make them effectively impossible.

You can level the same complaints about general relativity, but for some reason folks rarely do. Wonder why...

That's not the same thing at all. General relativity makes incredibly precise predictions about very specific phenomena. There have been hundreds of separate natural observational experiments (transit of mercury to gravitational lensing) and plenty of human created ones too (every GPS satellite in orbit).

Global climate science has it even harder than economics as an experimental science - we've got exactly one fully integrated system to observe, and we can't control for any of the variables. We can't re-run the same experiment again. We need to be objective and honest in how we communicate about climate science. Drawing false equivalences just undermines the very real and very urgent discussions we need to be having about climate as a species.

No. We have measured time dilation by putting atomic clocks in orbit.

You have to be clear about what is "settled". Understanding that we are changing the balance of greenhouse gases, and that those changes will have impacts on the biosphere and human society, is settled.

Specific predictions, i.e. future weather reports for specific parts of the planet--are far more complex and difficult. To precisely predict the impacts of human-caused climate change, you're combining all the reasons it's hard to predict the weather with all the reasons it's hard to predict the stock market and politics.

But that doesn't mean it's not happening. I can start a fire in your kitchen and challenge you precisely predict the patterns in the smoke at 10-second intervals with a resolution of 10 cm; you won't be able to. But we both know that your kitchen will be full of smoke after a while.

> Understanding that we are changing the balance of greenhouse gases

Are we? How settled is the science on anthropogenic part of AGW? Between the natural ocean cycle of carbon dioxide emission and absorption and constantly changing cloud cover and the generally chaotic climate system, how can we reliably tell that it is the human contribution in particular that is causing the changes?

Do you think that the sudden rise in co2 level after industrial revolution and the ever steepening slope is just a coincidence?

I don't know. But if all we have is a correlation, than calling it "settled science" is misleading.

We don't have the luxury of eating the investment on a "dry hole" when this is a global phenomenon. How is the path of highest caution not warranted here? What exactly are we losing by aggressively switching to renewables?

This isn't an academic question. It is an incredibly practical one.

That is a different argument , one that needs to be made.

OP is talking about people who spout doomsday predictions.

I once had a debate with someone who was convinced that humans were going extinct in the next century. He wasn't talking about migrations of hundred of millions, deaths of tens of millions, and climate patterns of droughts and floods changing, which are all present in predictions. He really believed that every single human was going to die. There are people who literally speak bullshit doomsday philosophy.

To be fair, all that is really required for human extinction is for us to start firing our nukes. Geopolitically destabilizing events increase the potential for that considerably.

That's not in any way to say that climate change must necessarily lead to thermonuclear war or anything so dramatic as that, but human extinction is a real threat hanging over our heads at all times. It's something worth being worried about.

Just remembered, he was basing this on the planet being uninhabitable soon.

I find that laughable. Despite how quickly and how chaotically the climate changes, we are not going to go extinct because earth is becoming uninhabitable

If we spend hundreds of billions of dollars fighting CO2 (capturing it, moving to more expensive energy sources, etc), that’s hundreds of billions of dollars that could have been spent elsewhere, on other problems like cancer, heart disease, etc.

Or hundreds of billions of dollars on football, flying cars, or whatever captures peoples' attention.

Or on proxy wars over more oil!

We (USA) could take it out of the defense budget if we tasked the military with climate security.

When you calculate risk/reward to efficiently allocate resources, you have to effectively estimate probabilities of both.

Yes some predictions are dire but if they have a one in a million chance of happening (for example) then it doesn't make sense to divert funds that could be better spent on more certain problems.