I note that I am confused by this diagram. In particular, the legend indicates a 90th percentile forecast of “>2100” for ASI, but the diagram appears to show the probability dropping to zero around the beginning of 2032.
I think it’s just that the tail is very long and flat with <1% per year. So, it looks like it goes to zero, but it stays just above.
Exactly. More fundamentally, that is not a probability graph, it’s a probability density graph, and we’re not shown the line beyond 2032 but just have to assume the integral from 2100-->infinity is >10% of the integral from 0-->infinity. Infinity is far enough away that the decay doesn’t even need to be all that slow for the total to be that high.
I think it’s just that the tail is very long and flat with <1% per year. So, it looks like it goes to zero, but it stays just above.
Exactly. More fundamentally, that is not a probability graph, it’s a probability density graph, and we’re not shown the line beyond 2032 but just have to assume the integral from 2100-->infinity is >10% of the integral from 0-->infinity. Infinity is far enough away that the decay doesn’t even need to be all that slow for the total to be that high.