If you’re not following Steve Goddard on Twitter or reading his stuff at Real Science, you should be. He posts a veritable flood of evidence pointing to global warming / human-caused climate change as manufactured nonsense. Yesterday, he Tweeted this.

It made me laugh, because it’s an effective lampooning of the most significant scientific problem with climate science — specifically, the part of climate science that claims human activity is changing the climate — which is its lack of predictive power.

If you read the news, it seems like climate change advocates are blaming everything on climate change. It’s warmer this summer than it was last year — climate change! It’s colder than we expected this spring — climate change! We’re getting record levels of snow — climate change! We’re getting the exact same number of hurricanes this season as we did a hundred years ago — climate change!

This is why climate change activists changed the terminology from “global warming” to “climate change.” Did you notice that bit of sleight of hand? Nobody except for those stuck in 20th century terminology refers to global warming anymore. This is because the average person was, not unreasonably, starting to wonder how global warming could account for every sort of climate phenomenon, including record cold temperatures. But everyone knows the climate has been changing since forever, so it doesn’t sound as nonsensical to attribute everything to climate change instead of global warming.

The problem with this is that any scientific model that predicts everything predicts nothing. The power of a scientific model is its ability to accurately and specifically predict what will happen given a set of inputs. Can you imagine how useless Newton’s universal law of gravity would be if it gave you every possible answer to the question of what the force of gravity is between two bodies of specific mass and at a specific separation? But that’s not much different than the current state of climate science.

As a scientist, I’ve been asked several times what it would take for me to believe that human-caused climate change is real. The answer is simple: evidence. The most powerful evidence would be predictive models that work. I would like to see models that accurately predict temperature trends, hurricane activity, rise in sea levels, and anything else that is currently attributable to climate change for ten years, based on a set of anticipated levels of “human activity.” Climate scientists would create their models, make their predictions based on how much CO₂ human activity is pumping into the atmosphere, and then we all see how accurately these predictions match the data for the next ten years.

Now, in order for me to be sure that these models and the data are accurately reflecting reality, I would need to see these results replicated by different groups who are not affiliated with each other. I would also need scientific transparency. I would need the climate models and the raw, unprocessed data as well as the processed data to be made freely available to anyone who requests them. And I would need a detailed explanation of how the data are processed for analysis.

I would feel significantly more confident in these models and data if climate change advocates would stop claiming “the science is settled,” emphasizing the bogus consensus, and demonizing people who are skeptical of climate change. No more labeling skeptics as “deniers,” and there must be a halt to egregious nonsense like threats from government officials to prosecute climate change skeptics.

If the models and data check out, and the models correctly anticipate temperature trends, hurricane activity, rise in sea levels, and anything else that is currently attributable to climate change for at least ten years, and climate change proponents stop behaving in a hysterical and unethical way, then I’ll believe human-caused climate change is real.

You can generalize all this and apply to any field of science to determine if it’s legitimate science:

• Do the models have predictive power?
• Do the models of different groups of scientists produce similar results?
• Are the models made available to others by request?
• Are the raw and processed data made available to others by request?
• Are the models and data deemed legitimate by others not affiliated with the scientists who promote them?
• Do proponents respond to reasonable skepticism with answers to objections instead of scorn, derision, and hysteria?

If the answer to ALL of these questions is YES, then you have a legitimate science.

My problem with climate science — the reason I am skeptical that human activity is changing the earth’s climate — is that, currently, the answer is NO to all of these questions.