Re: Scrap climate change "research".
"Observing the gas dynamics on Venus and extrapolating them for Earth is NOT a scientific test."
I didn't extrapolate anything on Venus to Earth, let alone claim it was a test.
My point is that the greenhouse effect exists and we can see it exists on both Venus and Earth. Venus just happens to be a super-obvious example of it. Do you dispute the greenhouse effect exists on Venus or just that it exists on Earth?
"There are completely different gases in Venus' atmosphere. It's proximity to the Sun is different. etc etc.
Venus' atmosphere is 95% CO2, it is incomparable to the trace gas amount on Earth."
Venus actually absorbs less sunlight than Earth. Yet it's far warmer than Earth. It's even warmer than Mercury which is closer to the Sun and absorbs even more sunlight than Venus. Why do you think that is? It is because of the 95% CO2 (and other greenhouse gases) that make up Venus's greenhouse effect.
Similar story for the Earth. The Earth's surface is far warmer than the sunlight Earth absorbs alone could maintain. Earth absorbs about 240wm-2 sunlight. A 240wm-2 blackbody would have an average temperature of no more than -18C. Yet Earth's average temperature is about +15C. The difference is because of the greenhouse effect.
"No it doesn't follow. If you say it follows then you show me how that conclusion came about and how you verified it."
"OK, you double CO2 levels and then get back to me with your results. I could build a time machine if I could rotate infinitely fast around infinitely long rotating cylinders in space. There's a test for time travel, therefore time travel is real!!!"
It matters a big deal what your hypothesis is based on. If you pulled it out of thin air then it's pretty much worthless without testing. But if it follows from something we have confidence in, such as general relativity, then some of that confidence transfers to the hypothesis. Especially if it follows from general relativity such that general relativity would be falsified if it wasn't true.
AGW is a result calculated from empirical observations and laws of physics we have confidence in. if AGW is wrong then a lot of empirical observations and laws of physics would be thrown into doubt. That's why people have confidence that AGW is right.
Similar way we have confidence that man evolved from ape-like ancestors. It's based on multiple lines of empirical evidence. We can't reproduce that evolution in a controlled lab to test it, but we can still be confident in the theory because the evidence points that way.
"But hypotheses should be 100% testable."
Yes, but that doesn't mean that until they are tested we can have no confidence in them. Positive empirical evidence does count for something.
"No it doesn't. The weight of extrapolated modelling may suggest this."
Climate models are not based on extrapolating past trends. Temperature data does not get fed into climate models as an input.
Our understanding of how the physics of climate work is coded into the model and then it is run to show what emerges. The output of climate models is the emergent behavior of subscale climate systems as we understand them.
All models, simple and complex exhibit AGW. Even napkin models of the climate do. It's so blatantly obvious that CO2 being a greenhouse gas and increasing CO2 will cause warming that it's simply fact. You can't avoid that answer if you plug the figures into physics equations.
"There is not much evidence to suggest this.And yet global temps are basically flat."
Not so. See the red line, it's tracked a similar upward path for the last 40 years:
"The 1930s were the second hottest decade by some measure of the last century."
Not so, they were much cooler than recent decades:
"What happened to CO2 in the 1940s~1980s?"
Given CO2 isn't the only factor influencing temperature, it's quite a good fit. You might have more concern for the idea the Sun can explain it.