From JoNova

By Jo Nova

Twelve thousand years ago sea levels around Africa rose much faster than today

It’s another totally solid, non-controversial paper that will never be mentioned in the media or by 50 shades of climate experts.

In extraordinary detail, Vecchi et al look at 347 datapoints up and down the west coast of Africa and find that, like everywhere else, sea levels were a blockbuster 125m lower at the depths of the ice age 25,000 years ago. Then seas rose in rapid bursts as the vast Laurentide and Eurasian ice sheets melted, until they finally stopped rising 8,000 years ago. It must have been twelve thousand years of mayhem for corals, mangroves and beach-side cave-dwellers.

In the northern Gulf of Guinea seas were recorded as rising at up to 25 mm per year about 12,000 years ago — eight times faster than anything we see today. And given the difficulty of knowing sea levels 15,000 years ago, there were probably many short episodes of faster shifts that got washed away, never to be recorded.

All our panic about the current crisis of a pitiful 3mm-a-year rise allegedly “due to man-made CO2” pales to nothing compared to what Monster Nature does. This study and hundreds like it, are like a stake through the heart of the vampire. For if the children understood the seismic shifts of the past, they would know that they were being sold a lie that the world had a stable and perfect climate or that current beaches have some sacred right to exist in perpetuity. Obviously, as commenters* pointed out, the Torres Strait Islanders ought to have a cultural memory of massive inundation, reefs shifting and the beaches being washed away. Like everywhere else in the world, Australian sea levels have been falling for 7000 years.

Thanks to Kenneth Richard at NoTricksZone who wrote that Africa’s Atlantic Coast Sea Levels Were Still 1 Meter Higher Than Today 2000 Years Ago.

And if natural rises can be eight times faster than what we see today, then how do we know the current rise is not partially or wholly natural? All we have are climate simulations…

Sea levels have fallen by 1 to 4 meters in last 5,000 years

Imagine the amount of work to collect all these data points from so many locations?

There were some sharp falls in sea level in the last 2,000 years.

From the paper:

These data represent the first Atlantic Ocean evidence of the sea-level lowering trend during the LGM [Last Glacial Maximum]. Previously, the Barbados record, was the single LGM dataset available for the Atlantic Ocean^2,8,10 but its accuracy in defining the timing and magnitude of the LGM was debated for possible tectonic influence⁸ as well as for the potential presence of allochthonous dated material from downslope transportation of the coral sea-level indicators²⁹. …

Rates of sea-level rise during the main phase of deglaciation

A major phase of deglaciation and consequent increase in global mean sea level occurred between ∼16.5 ka and ∼7.0 ka BP²⁴ from a reduction of land-based ice volume of ∼45 × 10⁶ km³.

From the Abstract:

From ~15 ka to ~7.5 ka BP, RSL shows phases of major accelerations up to ~25 mm a⁻¹ and a significant RSL deceleration by ~8 ka BP. In the mid to late Holocene, data indicate the emergence of a sea-level highstand, which varied in magnitude (0.8 ± 0.8 m to 4.0 ± 2.4 m above present mean sea level) and timing (5.0 ± 1.0 to 1.7 ± 1.0 ka BP).

The Results

In the northern Gulf of Guinea, RSL was stable at −61.6 ± 3.0 m between 14.0 ka and 13.0 ka BP (Fig. 3c). RSL rose to −44.9 ± 4.0 m at 12.0 ± 0.2 ka BP and to −37.2 ± 3.0 m at 11 ± 0.2 ka BP. Younger SLIPs indicate RSL rose to −6.1 ± 0.2 m at 8.0 ± 0.2 ka BP and finally to −1.6 ± 0.7 m at 7.0 ± 0.2 ka BP. The 9 SLIPs indicate two phases of major acceleration with rates of rise up to 25.2 ± 11 mm a⁻¹ between 12.6 ka and 12.1 ka BP and up to 11.6 ± 11 mm a⁻¹ between 10.0 ka and 8.0 ka BP (Fig. 3d). After 8.0 ka BP, RSL rates were <7.0 ± 2 mm a⁻¹ at 7.5 ka BP.

In Congo, RSL rose from −70.7 ± 3.9 m to −24.7 ± 1.7 m between 13.3 ± 0.2 ka and 10.0 ± 0.2 ka BP (Fig. 3e). Younger SLIPs indicate RSL rose to −4.3 ± 2.0 m at 8.0 ± 0.2 ka BP and reached present sea-level at 7.0 ka BP. The 9 SLIPs show sea-level rose at rates from 13.4 ± 3.4 mm a⁻¹ at 13.0 ka BP to 14.8 ± 1.8 mm a⁻¹ at 11.4 ± 0.2 ka BP (Fig. 3). This was followed by progressive decrease in rising rates from 10.3 ± 1.4 mm a⁻¹ after 9.0 ka BP to 6.0 ± 1.0 mm a⁻¹ after 8.0 ka BP, respectively (Fig. 3f).

Sea levels were higher in the Holocene, all over the world

Like giant oysters that used to live in the streets of Taiwan 7,000 years ago. Hundreds of Pacific Islands appeared out of the sea in the last 5,000 years as the seas receded, and these islands didn’t exist during the Holocene peak. 50 million years ago New Zealand was as big as India, then the ocean swallowed Zealandia. (So careless, they lost a whole continent.)

The fact is, according to 1000 tide gauges, spread all over the globe, sea levels are rising slowly at around 1 sole mm a year. And a nerd-level intense study of 60 beaches in Northern Europe showed a similar rise. By a strange coincidence the Topex/Poseidon satellite sea-level data set also showed the same tiny rates of sea level change in the 1990s — right up until they tortured the data to fit climate models. (We hear they calibrated the satellites to one sinking  gauge in Hong Kong).

Other posts on Sea Levels

• Sea level rise less than 1mm for last 125 years in Kattegatt, Europe — Nils-Axel Morner
• Are sea-levels rising? Nils-Axel Mörner documents a decided lack of rising seas
• Man-made sea-level rises are due to global adjustments (Envisat data is also adjusted up).
• It wasn’t CO2: Global sea levels started rising before 1800
• 10% of sea level rise is due to land rising too. Got that?
• South Pacific sea levels – Best records show little or no rise?!
• Mass carbon emissions, yet Australian sea levels rise at similar speed as 1920 – 1950
• Climate change creates free real estate in Tuvalu: “climate refugees” can all go home
• Rising sea-levels in the Indian Ocean due to man-made “adjustments” not CO2
• Kiribati sinking “like Titanic” but 59 million times slower
• Asian sea levels changed rapidly 6,000 years ago — natural sea level rise “unprecedented”

h/t El Gordo, NoTricksZone

*Ice age cultural remarks by David Maddison, MrGrimNasty, Jethro Bodeen, TdeF. 

REFERENCES

Vacchi, M., Shaw, T.A., Anthony, E.J. et al (2025) . Sea level since the Last Glacial Maximum from the Atlantic coast of Africa. Nat Commun 16, 1486 (2025). https://doi.org/10.1038/s41467-025-56721-0