Catastrophic Anthropogenic Global Warming (CAGW) is used by a lot of skeptics instead of AGW, the GreenHouse Effect (GHE), Climate Change, Climate Disruption, Carbon Pollution and any other alternate terminology that may be in use for Global Warming (GW). For some reason the real CAGWer's don't or pretend to not understand the C part.
The C part is the sales hook. Unless GW is bad, there is no reason to do anything about it that could be considered heroic. Business as usual would be dealing with fuel efficiency, building more nuclear power plants, planting more trees, restoring wetlands, all the stuff that we were doing before the big scare. In the US we agreed to less stuff and still ended up reducing emissions and increasing carbon storage with land use. With the exception of a few (around 10%) of the oldest Coal plants, that were kept in service probably longer thanks to impending regulation, most of our power plants are very clean by world standards. The US has spent plenty on Alternate energies with some hit and plenty of misses and with the exception of California have reasonable electric rates and overall good air quality. That isn't good enough for the "believers" so the threat of catastrophe is used to push for more.
If you Google Scholar, "Catastrophic Climate Change" you will discover several thousand "scholarly" papers that contain that exact phrase. Quite a few are written by economists that reference "fat tail probability". It is the fat tail or low probability, catastrophic impact potential that is the real C in CAGW. The "science" of fat tail probability seems to have originated with Blaise Pascal's Wager. Pascal was a 17th mathematician, philosopher and physicist that posed that all humans should believe in God because the odds are in your favor that way. If eternal damnation is the infinite catastrophe, any sacrifice for God was squat in comparison.
Since a large number of the CAGWer's are atheists and many are vocal advocate atheists, it is pretty ironic that they find Pascal's Wager useful. I guess there are no atheists in AGW foxholes. Scientifically, determining risk then the cost and benefit of action to offset some portion of the risk should be "business as usual".
The CAGWer's also take offense when a skeptic mentions they seem to approach CAGW more like a religion than a science. Since their mitigation models are based on Pascal Wager like logic, what exactly do they have to take offense about? All they are doing is preaching fire and brimstone the waving the mitigation "salvation" as a carrot. There is no guarantee any mitigation strategy they have proposed will be successful since they have no clue what degree of "catastrophe" might be forth coming or how much benefit any mitigation might produce. All they has is some unknown small possibility of any number of catastrophic events that can dream up. When a skeptic attempts to build some realistic number around their guestimated potential disaster, they cry foul and take their ClimateBall back home.
A large number of skeptics agree that mankind has some impact on climate but that so far that impact has been beneficial. People are living longer, eating better, breathing easier, enjoying abundant clean water in most cases, surviving shorter droughts with less effort, In fact most of the old scientists that started the GHE research believed it was not only beneficial but needed to avoid a new ice age. The real science of radiant physics predicts only about 1 C of warming is likely due to a doubling of CO2 and that 1 C of warming is likely beneficial. Speculative science has put the C in CAGW by including absolutely worst possible case amplification that still only nudges a potential C impact. Because of that the "projections" are running much higher than the observations.
Pointing any of this out is the Climate Science equivalent of blasphemy. Skeptical scientists have been shunned, scientifically and to some extent excommunicated from peer reviewed high impact journals. There is even email evidence of modifying the peer review process to exclude the non believers and at least one journal editor was force out for journalistic heresy, publishing a skeptical point of view. That is pretty weird shit in my opinion.
Just recently the editor of Science magazine managed to squeeze, climate change, the Pope and Dante's levels of hell in one opinion piece. Before long the US Supreme Court may have a chance to rule on the separation of Climate Change Church and State :)