Archives par mot-clé : Global Sea Level

climate-debate

Study: Sea Levels Rose 4.7 Centimeters Per Year 8200 Years Ago – 30 Times Faster Than Modern Rates

by K. Richard, Aug 26, 2024 in NoTricksZone

The modern rate of sea level rise is not even close veering outside the range of natural variability.

A new study reminds us that, 8200 years ago, near-global sea levels rose 6.5 meters in a span of just 140 years. This is 470 centimeters per century, 4.7 centimeters per year, during a period when CO2 levels were alleged to be a “safe” and stagnant 260 ppm.

Image Source: Nunn et al., 2024

To put this change rate in perspective, global sea levels rose at a rate of 1.56 millimeters per year from 1900 to 2018, including 1.5 mm per year rate during the more recent period from 1958-2014 (Frederikse et al., 2020, Frederikse et al., 2018). This is just under 16 centimeters per century or sixteen hundredths of a centimeter (0.16 cm) per year

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New Study: Sea Levels Have Receded Over Last 1500 Years, Including Since 1800s, Along India’s Coasts

by K. Richard, April 3, 2023 in NoTricksZone

Contrary to alarmist claims, the seas have been retreating and the coasts have been expanding seaward along the coasts of southern India since the early 1800s.

Korkai was a port city, capital, and the principal trade center for India’s Pandya Kingdom from the 6th to 9th centuries CE.

While Korkai was situated on the sea coast during the early stages of the Medieval  Warm Period, the city center is now approximately 5 or 6 km from the coast. This confirms the sea has substantially receded since then.

Nautical maps from the 1805-1828 period clearly affirm the coast of southern India has continued expanding seaward in the last 200 years, despite the reported rise in relative sea level (Gupta and Bhoolokam Rajani, 2023).

In other words, much more coastal land area is above sea level today than during the Little Ice Age, or when CO2 levels were said to be 280 ppm.

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Antarctic Ice Cap To Grow Despite Global Warming–New Study

by P. Homewood, Mar 29, 2023 in NotaLotofPeopleKnowThat

This study seems to have gone under the radar last year:

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https://doaj.org/article/df360f90269148b181055b409cd38204

So in short, under high emission scenarios, they reckon that the Antarctic ice cap will actually grow, with heavier snowfall more than offsetting glacial melt, leading to lower sea levels. And even under lower emissions the rate of melt will still be lower than currently.

Indeed according to scientists like Jay Zwally, the Antarctic ice cap has actually been growing in recent decades, for precisely this reason.

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Recent Shoreline Changes To Pacific Islands ‘Dwarfed’ By Change Magnitudes Of The Past

by K. Richard, Mar 6, 2023 in NoTricksZone

Most of the 1100 Pacific and Indian Ocean islands have been growing, not shrinking in size, in the last half century.

Activists convinced humans are able to exert fundamental control over ocean dynamics claim the rates of sea level rise and modern climate change are so rapid and unprecedented that modern changes are dramatically affecting shoreline movement on low-lying islands.

But a new study (Kench et al., 2023) assesses the opposite may be true. Recent shoreline changes (±40 m/50 years) are “dwarfed” by the shoreline changes (±200 m/100 years) that occurred throughout previous centuries. Globally, here is nothing “unprecedented” about what has been occurring with reef island shoreline dynamics in recent decades.

Of the global database of 1,100 Pacific and Indian Ocean reef islands, the “dominant mode of response has been the expansion of islands on reef surfaces (>53%)” over the last half-century. Only 0.3% (3 of 1,100) of islands have experienced “total loss.” Similarly, Duvat (2019) found 89% of 709 global-scale islands have been either stable or growing in size since the 1980s.

Of the islands sampled for the study, none are older than 1,400 years. Before then, they were submerged beneath the sea due to the much higher sea levels of the past.

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better to know...?, climate-debate

Science Yields Surprises! Island Nations Growing… “Atoll, Island Stability Is Global Trend”!

by P. Gosselin, Mar 8, 2023 in WUWT

IPCC high-end sea level predictions for 2100 are “highly erroneous”. 

Global warming alarmists like to claim that Pacific island nations are on the verge of disappearing – due to rising sea levels caused by polar ice melting due to global warming, which in turn supposedly is caused by rising concentrations of “heat-trapping” trace gas CO2 from the burning of fossil fuels.

These coral reef island nations risk going under real soon, unless we wean ourselves from fossil fuels soon, they say.

Coral reef island nations are emerging, not disappearing

But yesterday Kenneth here presented a new paper appearing in Nature, (Kench et al., 2023), which looks at whether the coral reef islands are in fact seeing unprecedented and undergoing accelerating physical changes that risk outrunning human adaptation measures. The authors analyzed the dynamics of a Maldivian reef island at millennial to decadal timescales.

Recent changes not unprecedented

The researchers found that “island change over the past half-century (±40 m movement) is not unprecedented compared with paleo-dynamic evidence”.

Nothing unusual is happening. The global data suggest that almost all islands are in fact growing, and not  disappearing under water like climate alarmists mistakenly believe.

“Recent shoreline changes (±40 m/50 years) are ‘dwarfed’ by the shoreline changes (±200 m/100 years) that occurred throughout previous centuries,” the study’s authors write.

 89% of all the globe’s islands are stable, or growing!

Moreover, just 4 years ago, another peer-reviewed publication appearing in a renowned journal found similar results: 89% of the globe’s islands and 100% of large islands have stable or growing coasts! According to Duvat, 2019:

“88.6% of islands were either stable or increased in area, while only 11.4% contracted. It is noteworthy that no island larger than 10 ha decreased in size. These results show that atoll and island areal stability is a global trend, whatever the rate of sea-level rise.”

Moreover, Khan et al (2018) found: “Prediction of 4–6.6 ft sea level rise in the next 91 years between 2009 and 2100 is highly erroneous.”

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New Studies Suggest Sea Levels Were 2-5 Meters Higher Than Today ~6000 Years Ago

by K. Richard, Oct 13, 2022 in NoTricksZone

From about 5000 to 7000 years ago, when Earth was several degrees warmer than it is today, there was more water locked up on land as ice. Consequently, relative sea levels were much higher and land areas now well above sea level were submerged beneath the sea.

None of these paleo indicators suggest warmth, ice melt, or relative sea level are consistent with claims CO2 is a climate driver.

1. Hapsari et al., 2022

2. Angulo et al., 2022

3. Watanabe Nara et al., 2022

4. Angulo et al., 2022

5. Angulo et al., 2022

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climate-debate

We’re Not Gonna Drown! Analyses Show COASTAL SEA LEVEL RISE Is Only 1.69 mm Per Year!

by P. Gosselin, March 23, 2021 in NoTricksZone

UPDATE: Sea level rise near the coasts where people actually live is found to be 1.69 mm/yr. But when crunching the data for the entire ocean, as Willis Eschenbach has shown, a figure of just 1.52 mm/year is computed. 

Hot shot data analyst Zoe Phin at her site examines sea level rise.

There she notes, “Climate alarmists are worried that the sea level is rising too fast and flooding is coming soon. You can find many data images like this on the net:”

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