[timr]

> When we compare those to what actually happened up to 2025, we see that we are slightly worse right now than their highest sea level prediction that was made.

No. The paper does not show that. Figure 3 shows that recent sea level rise, accounting for measurement uncertainty, is in line with projections of any of the models (around 2mm per year). In any case, they call out explicitly that the recent data is of insufficient duration to make the comparison you’re trying to make.

Temperature data in figure one is more or less exactly in the uncertainty window of the models (not shocking, considering that they’re calibrated to reproduce recent data).

[317070]

I'm sorry, but I double checked and I do think you have it wrong. Figure 3 is for "sea level rise _rate_", and that one is indeed high but not significantly so.

Quoting "The satellite-based linear trend 1993–2011 is 3.2± 0.5 mm yr−1 , which is 60% faster than the best IPCC estimate of 2.0 mm yr−1 for the same interval"

But, as the authors point out, the worst case forecasts that were within-data, are so for the wrong reasons. Quote "The model(s) defining the upper 95-percentile might not get the right answer for the right reasons, but possibly by overestimating past temperature rise."

My previous comment is regarding Figure 2, i.e. "Sea Level". I would invite you to read the whole paper. It is only 3 pages and written without jargon.

[timr]

Sea level rise rate is what matters (we cannot measure “sea level” absolutely, and therefore must work in terms of relative rates of change). The authors explicitly tell you that the data is not sufficient to conclude what they’re alluding:

> this period is too short to determine meaningful changes in the rate of rise

Now, you note that the authors openly acknowledge that the rate of rise is measured in low-single-digit units of millimeters per year. So, why is the y-axis of Figure 2 measured in centimeters?

Hint: it’s because every point on that plot is a wild extrapolation.

This paper is not good, btw. The fact that it’s “only three pages” should be a blinking red sign telling you that it is not serious. Just read the more recent IPCC reports, because they deal with the question of updates from prior reports.

[317070]

> Hint: it’s because every point on that plot is a wild extrapolation.

I don't understand, or do not spot the issue you are seeing. Could you expand a bit?

[timr]

The plot you're citing is an imaginary projection 100 years into the future given what was known up to the year on the x-axis. That is why the units are 100x larger.

The uncertainty on the rate of change is quite large (relatively), therefore, any 100 year projection has huge, compounded uncertainty. Figure 2 is not useful for determining anything about the present.