No, the models aren't uncertain based on human action. Again, this is something I've been steeped in for decades. The models are wildly divergent because of how much uncertainty exists over the dynamics of climatology. They can make varying assumptions about CO2 emissions and produce ranges based on that, but even without those inputs, the models are still
very different. Some are doomsday scenarios, some are rosy. There was never any sort of authoritative model that anyone could point to as "This is how much the temperature will rise given input conditions" or "This is how much future flooding will increase". Instead there were probabilistic estimates using the best fits of a plethora of different models. When the USACE used models to predict PMP/PMF for future weather systems to adjust the 100-year flood guess for a river system, it didn't plug numbers into one model, it modeled all the models and took the middle.
And again, there were so many models of such divergent prediction that there's no accuracy to saying "They underestimated" or "They overestimated" the impacts. Its somewhere between misleading and meaningless. If you have a room of 100 people and ask them how many marbles are in a jar, and each person gives a different answer, can you say "They overestimated"? Maybe if you take the average of each person's guess, but what if one person says 10 billion and another few guess it on the nose? Will you remove outliers or look at median? Those are
exactly the sort of questions that civil engineers and climatologists have been working on for decades when it came to climate modeling, because of all that uncertainty in the models. But as I stress, the models almost all converge on simple obvious trends like "we're getting warmer over time" and "probable maximum flood events have a higher maximum cap"
Here's an example of what it looks like when 44
different models are mapped against historic data;
https://i.imgur.com/zJDOhGs.pngClimate change deniers just
love to look at how 'most' models overestimated how much global warming there would be in the past 20 years, but several models can explain that as a temporary cyclical cool period that might precede a sudden rapid increase as the lag catches up to us (as the data since 2015 might indicate). Some might predict its just a lower gradient than the other models. But they all agree its going up, and it did. There's a reasonable debate to have about what % of global warming is actually anthropogenic vs natural, if there are diminishing return factors or feedbacks not being accounted for, and whether there are unknown novel variables not understood. That one oddball guy even had a model theorizing sun magnetosphere cycles and cloud formation by cosmic ray seeding being able to account for a small % of variation. Was there anything true about it? Fuck if I know, but I know there's something wrong with science if you can't even suggest that theories might be flawed or incomplete when the observable evidence doesn't agree with them.
Thanks for a great example.
The graph you linked is nearly 10 years old at this point and was specifically made by Roy Spencer, a young earth creationist, cherry picking models. You just proved my point on how incredibly dishonest you are.
I feel like the real problem is that the people who presented the data decided to take the worst case scenario and push it for their own benefit and we won't get a real answer of "Well we don't really know what will happen" or something similar. Of course there are people that say that but most of the people who speak for their constituents and get "air time" only ever say it's doomsday very soon or it's not happening at all. They try to enact legislation based on these extremes and its pushing a divide into the populace. I guess that describes anything at this point.
See my response. This is what Goomshill does. He learns as much as he can and then cherry picks the data to present.