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climate and geology

Elegantly modeling Earth’s abrupt glacial transitions

by American Institute of Physics, Mar 7, 2023 in ScienceDaily

Proxy data — indirect records of the Earth’s climate found in unlikely places like coral, pollen, trees, and sediments — show interesting oscillations approximately every 100,000 years starting about 1 million years ago. Strong changes in global ice volume, sea level, carbon dioxide concentration, and surface temperature indicate cycles of a long, slow transition to a glacial period and an abrupt switch to a warm and short interglacial period.

Milutin Milankovitch hypothesized that the timing of these cycles was controlled by the orbital parameters of the Earth, including the shape of its path around the sun and the tilt of the planet. A slightly closer orbit or more tilted planet could create a small increase in solar radiation and a feedback loop that leads to massive changes in climate. This idea suggests that there may be some predictability in the climate, a notoriously complex system.

In Chaos, by AIP Publishing, Stefano Pierini of Parthenope University of Naples proposed a new paradigm to simplify the verification of the Milankovitch hypothesis.

“The main motivation behind this study was the wish to characterize and illustrate the Milankovitch hypothesis in a simple, elegant, and intuitive way,” Pierini said.

Many models suggest that Milankovitch is correct; however, such methods are often detailed and study specific. They incorporate climate feedback loops — for example, increased ice cover reflects more radiation back into space, leading to further cooling and more ice cover — as threshold crossing rules. This means that an abrupt jump in climate only occurs once a parameter reaches a given tipping point.

Pierini’s “deterministic excitation paradigm” combines the physics concepts of relaxation oscillation and excitability to link Earth’s orbital parameters and the glacial cycles in a more generic way. The relaxation oscillation component describes how the climate slowly returns to its original glacier state after it is disturbed. At that point, the excitability piece of the model captures the external orbital changes and triggers the next glacial cycle.

By using his own threshold crossing rules and adopting a classical energy-balance model, Pierini obtained correct and robust timing of the most recent glacial cycles.`

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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.”

better to know...?, climate-debate

From Record Snow To No Snow, Activist Media Use Climate Change To Stoke Fear

by J. Heller, Mar 7, 2023 in ClimateChangeDispatch

This article is in the tradition of articles that we have seen for decades saying we could look forward to snowless winters because of humans and our use of natural resources.

What is missing from every one of these articles is a direct link connecting oil consumption, CO2 content, or any other such thing with temperatures and snow. [emphasis, links added]

But the truth has never mattered to the media and other leftists when they have set out to destroy the oil industry.

They cannot explain why we had a cooling period from 1940 to 1975, where essentially the same people who are warning of an existential threat of warming were warning of an existential threat that billions would die from an existential threat of a coming ice age.

Here is a hint for sycophant journalists who just repeat what they are told.

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