Minor correction.

Science is anything that follows the scientific method.

One important step of the scientific method is "make testable predictions." Another step is "refine, alter, expand, or reject" hypotheses. Science rests on the possibility of falsifiability. If it can be tested, and found false, it is science. If there is no way to falsify it, it is not science.

For instance, evolution is falsifiable. We can expect that if we put certain organisms with rapid life cycles in a harsher environment, over a certain number of generations the population in the harsher environment will evolve to better suit that environment. If, say, 10,000 generations pass and the organisms in that environment are no better suited to it than a control population, we might conclude evolution has been falsified. Fortunately, we've done lots of tests like this, and evolution does indeed occur.

So I may better understand how this is science, can you tell me how the theory of manmade global warming can be disproved?

Have you read the IPCC Summary for Policymakers? It's a really good summary of the current state of the science. It's a very complicated topic and you're not going to get a complete answer in a HN reply. I'm serious, give it a read.

http://www.ipcc.ch/pdf/assessment-report/ar5/wg1/WG1AR5_SPM_...

I'm going to go with a prolonged period of worldwide cooling?

Lab tests that show CO2 is not a greenhouse gas?

Isotope concentrations that show increasing CO2 is not coming from anthropomorphic causes?

Evidence that the glaciers are melting because of some other reason than it's hot?

One way to disprove it would have been if global temperatures had stayed at their 19th century levels. Starting from where we are now, it would be disproven if global temperatures returned to their 19th century levels.

There are reasons to object to the accord that have nothing to do with a so-called "anti-science policy".

The actual wording of the accords has little to do with science and more to do with massive welfare obligations and handicapping the US economy with no requirements from China for decades.

*edited autocorrect typo

Climate change denial has been a Republican position for decades. Trump is on record saying that the whole idea is a hoax. There might be legitimate reasons to pull out of this agreement, but those are not their reasons.

Massive welfare to the majority of the world for no US benefit is a great reason to pull out.

I think you missed what I said. That may be a great reason, but Trump and friends are pulling out because they don't think climate change is even real.

What does a climate treaty that benefits the US economy in the short term, and is politically feasible, look like?