Scientifically speaking, the concept of anthropogenic global warming (AGW) is a hypothesis, not a theory.
A theory is a conceptual framework informed by experimental and observational data. Theories tend to be revised and refined over time as more data becomes available. While there are theories on climate change, the actual theories are built on the observations of solar activity, orbital variances, and other cycles which affect the earth.
Ideally, in order for an idea to qualify as a hypothesis, it would have some element of testability. I'm not certain of the testable aspects of the AGW idea. A hypothesis must also be accompanied by a null hypothesis. Thus, a hypothesis and its null are stated, "If A is an actual phenomenon and we perform experiment B, we should expect to see result X. However, if A is not the case, we should expect to see result Y from experiment B." On the contrary, all I've ever seen (in countless scientific papers) is, "We observed A, and that proves AGW!" And such a statement is pronounced with the same kind of breathless excitement that CNN anchors use to pronounce that yet another nothingburger is absolute proof of Trump/Russia collusion.
Global Cooling and Global Warming were disprovable when none of their predictions came true. This is why they have now switched to Global Climate Change. It is a hypothesis that can never be proven false.
Is it warmer than usual today? It is because of Global Climate Change.
Is it colder than usual today? It is because of Global Climate Change.
Is it wetter, dryer, windier, less windy, cloudier, less cloudy? It does not matter! Whenever bad weather strikes anywhere in the world it is because of Global Climate Change.
The only solution is more taxes and government control of the economy.
Most Climate Change warriors believe it's FACT, and will spout the idiocy that 97% of ALL scientists think it's true. Convincing them it's only a theory takes a bit of doing, let alone going as far as calling it a hypothesis.......