Is This What ‘Settled Science’ Looks Like?

Ice in the Phanerozoic…

Throughout the Phanerozoic, Earth experienced significant periods when the planet was largely ice-free or had significantly reduced global ice cover.

During the Cambrian Period and the subsequent periods of the Early Phanerozoic, there is limited evidence to suggest the presence of widespread ice cover. [emphasis, links added]

The climate during this time was generally warm, and the planet lacked extensive glaciation.

Moving into the Mid-Paleozoic, including the Silurian and Devonian periods, warm climates prevailed with limited glaciation.

Fossil records indicate the presence of diverse marine life and relatively high sea levels, suggesting reduced ice cover during this period.

The Late Paleozoic saw the occurrence of a major ice age known as the Late Paleozoic Ice Age, but evidence for extensive ice cover in the northern hemisphere is limited.

While significant glaciation occurred in the southern hemisphere, many parts of the world may have been relatively ice-free during this time.

During the Mesozoic Era, including the Triassic through the Cretaceous periods, and the subsequent Cenozoic Era, warmer global climates prevailed with reduced ice cover.

Although there were no extended ice-free periods comparable to the present interglacial period, the polar regions likely had diminished ice extent, particularly during the warmer intervals.

Predictions of Arctic sea-ice extent…

Future predictions of Arctic sea-ice extent suggest that the region will continue to experience changes in ice cover due to ongoing climate change.

These predictions are based on climate models that incorporate various factors such as greenhouse gas emissions, atmospheric and oceanic circulation patterns, and feedback mechanisms.

Most climate models project a continued decline in Arctic sea ice extent throughout the 21st century.

The rate and magnitude of this decline can vary depending on different greenhouse gas emissions scenarios and model assumptions.

However, even under more conservative emission scenarios, most projections indicate a substantial reduction in summer sea ice extent compared to the historical average.

By the mid-21st century, some projections suggest that the Arctic could experience ice-free conditions during the summer months, meaning that the extent of sea ice would be significantly diminished or even absent.

However, it’s important to note that ice-free conditions do not imply a complete absence of ice, as some ice may still persist in protected areas or during the winter months.

In fact, a recent study published in the journal Nature titled, “Observationally-constrained projections of an ice-free Arctic even under a low emission scenario” concluded…

Our observationally-constrained projections based on attribution results also suggest that we may experience an unprecedented ice-free Arctic climate in the next decade or two, irrespective of emission scenarios. This would affect human society and the ecosystem both within and outside the Arctic, through changing Arctic marine activities as well as further accelerating the Arctic warming and thereby altering Arctic carbon cycling.

And of course, this prediction has made headlines…

However, another recent study also published in the journal Nature titled, “Coupled stratosphere-troposphere-Atlantic multidecadal oscillation and its importance for near-future climate projection” concluded…

The introduced coupled oscillation and associated statistical climate projection suggests that the ongoing negative NAO-trend will continue (Fig. 7), which can lead to further increase (decrease) of the precipitation in the Southern (Northern) Europe, a weakening of the AMOC and subpolar Atlantic-gyre and therefore to multidecadal sea-ice extension and Atlantic cooling trend, like the period 1950s–1970s (Figs. 1b and 7). This can offset the long-term Arctic sea-ice melting, north of the Atlantic basin, leading to sea-ice melting hiatus (Fig. 1b and 7).

The reduction in Arctic sea ice has various implications for the climate system and ecosystems.

It’s believed to contribute to a positive feedback loop known as the ice-albedo feedback, wherein less ice cover leads to increased absorption of solar radiation by the darker ocean surface, further amplifying warming in the region.

However, the fact that Earth has cycled between ice-free time periods only to return to ice conditions suggests this feedback mechanism is easily overcome by other natural forcings.

While future predictions provide valuable insights, it’s important to acknowledge that there are uncertainties in modeling complex climate systems.

Factors such as natural climate variability, model limitations, and the potential for nonlinear or abrupt changes can influence the actual trajectory of Arctic sea-ice extent.

In summary, the Arctic will be either ice-free or experience a significant increase in sea-ice concentration in the 2030s, depending on which study you choose.

However, of these two results, only one made significant headlines in the MSM. Is this what ‘settled science’ looks like?

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