By “they” I meant RC.

I know that it’s a known factor, I’m just wondering if they took it into account.

I didn’t see it, but I may have missed it.

That is what I thought.

What I don’t get is why they felt the need to adjust the sea level rise data for the volume change based on sinking basins and rising coasts, but not the need to adjust the data for the volume change based on thermal expansion?

Doesn’t it make sense to adjust for all volume changes, if they are going to adjust for any?

The other thing I don’t quite understand is aren’t all the old tide gauge measurements made relative to the coast – in other words not relative to the center of the Earth.

By adjusting for GIA they are converting a relative measurement (how high sea level is relative to the coast at a particular tide gauge), to an absolute measurement (how high is the sea level, keeping the volume of the basin holding the ocean constant).

To me, the relative measurement is the important one.

If sea level rises relative to Florida 1 meter by 2100, I assume a lot of land will be covered.

However, if Florida rose 1 meter and the ocean rose 1 meter, so no relative difference in land lost to the sea, who cares?

Any thoughts on these questions are welcome.

The latest RC post mentions an adjustment (they used it for acceleration) which I was surprised to see is somewhat significant – the amount of water held in manmade reservoirs.

I know they just adjusted it for GIA – which is really a volume adjustment, as the ocean basins are larger today than 1850, due to glacial rebound and basins sinking (on average).

But what about the volume change to the ocean based on thermal expansion. It is .8C warmer than 1850, so has the a similar volume adjustment been made to the sea level data to account for thermal expansion?

I have been unable to determine if both volume adjustments are incorporated into the sea level rise data, or just the GIA adjustment.

It would seem to me that these two different volume adjustments offset each other.

It would also seem to me that if one volume adjustment is being made, both should be made.

Change your assumption. Consider that the purpose of the Kemp paper is to support a specific hypothesis.

Multiple locations were examined until one was found that satisfied the hypothesis, and the data from that site was used for the study. The contrary data was not disclosed.

This then allows them to publish and say the data supports the hypothesis. This was what was done with the hockey stick. Why would this study be any different?

Having violated the scientific method previously, why assume that this would not be repeated in subsequent studies?

The assumption that the purpose of the study was to conduct science is in error. The purpose of the study is not to conduct science. It is to provide evidence in support of a hypothesis, while appearing to be science.

If you want to get a grasp of local sea level changes, then check out the history of “Long Beach Harbour” on wikipedia. Sank several feet due to oil extraction at the wilmington field. Long Beach Harbour has two tide gauges. One can speculate what they are likely to tell you about sea level over the longer term.

The fact is that heavy concrete harbour walls are ideal places to put tide gauges when you want to know if you can dock the QEII or whatever. Not so ideal if you want to monitor sea levels over 100yrs – they have a tendency to sink into the mud or get their foundations washed away. Just google “subsidence” together with “harbour”, “Quay” or “dock” and you will get the picture. Tide gauges will always give high readings for sea level change because of this subsidence – but the tide gauge readings aren’t that worrying anyway.