The answer to the second question, I think, is “some”. It is not 100% and it is not 0%.
Interpreted literally, this statement is obvious but useless. I expect you meant “it is something strictly between 100% and 0% and not particularly close to either one” (i.e. between 10% and 90%), which is a stronger statement, and not obvious a priori (not all trends have multiple unrelated causes). On what basis do you make that claim?
As far as I remember it is usually held that the positive consequences (e.g. better harvests, etc.) overwhelm the negative until the about +2 degrees C rise in the temperature, but it’s all very uncertain.
I have heard it claimed that there is a consensus that the effects of warming will be positive through +2 C, but the sources making that claim seem to be quite short of a consensus themselves.
The fifth question, the most interesting of them all, is not in the domain of the climate scientists at all. It is essentially a social and a political question the answers to which are driven by values and trade-offs.
I expect you meant “it is something strictly between 100% and 0% and not particularly close to either one”
Yes, I do.
On what basis do you make that claim?
Earth has been warming up for a while (in terms of centuries) by now—we’re still coming out of the last Little Ice Age. On a more short-term scale for when we have direct instrumental data, I believe (from memory) that the current warming trend started around 1850 which is too early for CO2 to make a noticeable impact. And, of course, the graph of the global temperatures and the graph of the CO2 concentration in the atmosphere do not match too well.
The short answer is that it’s complicated and the temperature trends do not look like they’re driven solely by the very evenly increasing CO2 concentration. As to not being 0%, well, physics.
That doesn’t answer the question, though.
Not directly, no, but it does imply that the answer will be different for different groups of people.
Interpreted literally, this statement is obvious but useless. I expect you meant “it is something strictly between 100% and 0% and not particularly close to either one” (i.e. between 10% and 90%), which is a stronger statement, and not obvious a priori (not all trends have multiple unrelated causes). On what basis do you make that claim?
I have heard it claimed that there is a consensus that the effects of warming will be positive through +2 C, but the sources making that claim seem to be quite short of a consensus themselves.
Indeed. That doesn’t answer the question, though.
Yes, I do.
Earth has been warming up for a while (in terms of centuries) by now—we’re still coming out of the last Little Ice Age. On a more short-term scale for when we have direct instrumental data, I believe (from memory) that the current warming trend started around 1850 which is too early for CO2 to make a noticeable impact. And, of course, the graph of the global temperatures and the graph of the CO2 concentration in the atmosphere do not match too well.
The short answer is that it’s complicated and the temperature trends do not look like they’re driven solely by the very evenly increasing CO2 concentration. As to not being 0%, well, physics.
Not directly, no, but it does imply that the answer will be different for different groups of people.