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SLR is more complicated than global warming by GHGs. Post-glacial rebound, land subsidence, land use practices....

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The CRC Science Panel's 2010 Report was a mess. I critiqued it here:

https://burtonsys.com/climate/Critique_of_NC_2010_SLR_AR.pdf

The critique is 29 pages long, but here's the summary:

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Unfortunately, the Report is riddled with errors. It is strikingly unscientific in its approach, and its conclusion is wildly wrong:

• It began by cherry-picking a single, outlier NC tide station as representative of the State, obviously chosen for its atypically large rate of recorded sea level rise.

• It used just 24 years of sea level data from that tide station, despite the fact that 32 years of data were available, and other NC tide stations had over 75 years of data available.

• It conflated sea level measurements from coastal tide gauges with mid-ocean sea level measurements from satellites, creating the illusion of an increase in rate of sea level rise.

• Then it applied a discredited methodology from a fringe alarmist researcher, to justify predicting a wildly accelerated rate of sea level rise, far beyond even the IPCC’s alarmist predictions.

• Then it exaggerated even his implausible projections.

• Worst of all, it never even mentioned the fact that the actual historical record of sea level has shown no sustained acceleration in rate of rise for over 80 years, neither globally, nor here in North Carolina. That is the single most important thing to know about sea level rise, but you can’t learn it from this Report.

The Report recommends planning for one meter (39 inches) of sea level rise by 2100, for all of North Carolina.

That is absurd. The best science indicates that most of the NC coast will see only 3-14 inches of sea level rise by 2100, though in northeastern NC 12-20 inches is likely due to land subsidence.

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Arguably, the best sea-level measurement record in the world is the 117⅚-year record from Honolulu. It's not the longest measurement record in the world, but:

● Unlike the U.S. east coast, Hawaii is not affected by variations in the Gulf Stream.

● Honolulu has 117⅚ years of continuous, top-quality measurements, from the same location, with no gaps.

● Honolulu’s location near the middle of the Pacific is nearly ideal. The Pacific Ocean “sloshes east” during El Niños, and “sloshes west” during La Niñas, but Hawaii is near the “teeter-totter pivot point,” so, unlike the other long Pacific measurement records, Honolulu is scarcely affected by it.

● Oahu experiences only small tides, and almost no vertical land motion (though it does move horizontally, about 3″ to the northwest, each year). Oahu is an old, tectonically stable island (several million years old, which is about 4× the age of the Big Island), and the volcanoes on Oahu are believed to have been inactive for well over a million years. So Honolulu’s sea-level trend is typical (about the same as the global average, i.e., about +1½ mm/year = 6 inches/century), and it is not appreciably distorted by vertical land motion.

https://www.nps.gov/havo/learn/nature/volcanoes.htm#:~:text=As%20it%20moves%20an%20estimated%202-4%20inches%20per%20year,%20it%20carries%20with%20it%20any%20land

● Unlike the north Atlantic and Baltic, Hawaii is not appreciably affected by Greenland’s slowly changing gravity field.

https://sealevel.info/resources.html#icegravity

There are other sites with measurements going back even further than Honolulu’s, but all of them either have gaps in the records, or they are sited at less-than-ideal locations.

Here's Honolulu's sea-level measurement record, juxtaposed with atmospheric CO2 concentration:

https://sealevel.info/MSL_graph.php?id=Honolulu

https://sealevel.info/1612340_Honolulu_thru_2022-10_vs_CO2_annot1.png

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