Those are not two theories; they are more like complimentary consequences.
The ocean absorbs excess CO2 from the atmosphere. If it absorbs it as fast as we produce it, there will not be any warming, but a lot of acidification.
If it absorbs it much more slowly, then there will be a lot of warming but little acidification. The truth is somewhere in between.
What I don't get is the other part of this statement. Acids, by definition, contain chemical energy that can be harvested by life.
What is the basis for the assumption that any ocean acidification won't suddenly disappear, because some algae species decided it is now sufficiently widespread and easy to acquire to use it for lunch ?
The whole reason to do anything about the acidification is that it's "not natural". Nature adapting to changing circumstances is the very definition of what nature is. You can't have it both ways.
Plus it won't be catastrophic at all. Some very low-level species, like algae, will adapt by changing their internal chemistry. And because we eat them (through intermediaries) we will have effectively adapted too.
And don't you believe in evolution ? If this doesn't happen, then we die, and in that case we should die. The whole point of creation is that it adapts to these sort of things. Adapt or die. Works on a large scale as well as a small one.
That is not the reason to worry about acidification. The reason is that we like coral reefs, and don't want them to die out. Not only are they beautiful, they are great sources of biodiversity (good for research), and they protect many sea-level human installations like shipping harbors and city waterfronts.
"What situation would falsify the theory of catastrophic anthropogenic global warming"
A rapid unexplained significant decline in global temperatures over a decade despite increasing carbon use would clearly falsify the idea of AGW.
edit: or just a theory that explains global temperature trends better than the current climate models that use anthropogenic carbon emissions. Or data that conclusively overturns the record of recent warming.
Ok, but what would need to happen to demonstrate that global warming is not happening? If the warming stopped or reversed over a 5 year period? 10? 20? 50? Never?
"to demonstrate that global warming is not happening? If the warming stopped or reversed"
You can't stop/reverse something that's not happening, that's not even coherent.
If it's not happening you need better data showing it isn't happening or reasons why the current data is being massively misread.
If, all else being equal[1], global warming is happening and then stopped/reversed without anthropogenic carbon emissions going down then the case for rejecting AGW gets stronger. You'll need a replacement theory/model though. At what point does the new model become more convincing then the current one? Scientific consensus might be a good starting point.
[1] obviously if a bunch of volcanos or nuclear winter are responsible for the cooling that's not going to falsify the ideas behind AGW. For example, cooling in the 1940's.
"5 year period? 10? 20? 50?"
How much reversing are we talking about? We have 100+ years of warming to reverse. The fact that it's hard to easily falsify AGW isn't because AGW is unfalsifiable, it's because the science and data supporting AGW is enormous.
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You can't stop/reverse something that's not happening, that's not even coherent.
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No need to get hostile. I was referring to two possible outcomes: (1) global warming was never occurring (2) global warming was happening, but for what ever reason stopped or even reversed.
The ocean absorbs excess CO2 from the atmosphere. If it absorbs it as fast as we produce it, there will not be any warming, but a lot of acidification.
If it absorbs it much more slowly, then there will be a lot of warming but little acidification. The truth is somewhere in between.