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The Hill Pushes Discredited Ocean Acidity Scares

Coral cover is breaking records, real world data proves ocean life loves CO2, but none of this impedes a never-ending drip feed of ocean acidification scares.

From Watts Up With That?

Essay by Eric Worrall

Coral cover is breaking records, real world data proves ocean life loves CO2, but none of this impedes a never-ending drip feed of ocean acidification scares.

‘Ticking time bomb’: Ocean acidity crosses vital threshold, study finds

BY SAUL ELBEIN – 06/09/25 11:24 AM ET

The deep oceans have crossed a crucial boundary that threatens their ability to provide the surface with food and oxygen, a new study finds.

Nearly two-thirds of the ocean below 200 meters, or 656 feet, as well as nearly half of that above, have breached “safe” levels of acidity, according to findings published on Monday in Global Change Biology.

The fall in ocean pH is “a ticking time bomb for marine ecosystems and coastal economies,” Steve Widdicombe, director of science at the United Kingdom’s Plymouth Marine Laboratory (PML), said in a statement.

The study was funded in part by the National Oceanographic and Atmospheric Administration (NOAA), a federal agency that has been targeted for steep cuts by the Trump White House, in large part because of its role in investigating climate change.

…Read more:

https://thehill.com/policy/equilibrium-sustainability/5340239-ocean-acidity-study-climate-change-carbon/

The referenced study;

Ocean Acidification: Another Planetary Boundary Crossed

Helen S. Findlay, Richard A. Feely, Li-Qing Jiang, Greg Pelletier, Nina Bednaršek

First published: 09 June 2025

Funding: This work was supported by European Space Agency, AO/1-10757/21/I-DT. Natural Environment Research Council, NE/X006271/1. NOAA’s Global Ocean Monitoring and Observing and Ocean Acidification Programs, GOMO Fund Reference Number 100018302 and OAP NRDD. Slovene Research Agency, N1-0359. Climate Program Office, NA19NES4320002, NA210AR4310251.

ABSTRACT

Ocean acidification has been identified in the Planetary Boundary Framework as a planetary process approaching a boundary that could lead to unacceptable environmental change. Using revised estimates of pre-industrial aragonite saturation state, state-of-the-art data-model products, including uncertainties and assessing impact on ecological indicators, we improve upon the ocean acidification planetary boundary assessment and demonstrate that by 2020, the average global ocean conditions had already crossed into the uncertainty range of the ocean acidification boundary. This analysis was further extended to the subsurface ocean, revealing that up to 60% of the global subsurface ocean (down to 200 m) had crossed that boundary, compared to over 40% of the global surface ocean. These changes result in significant declines in suitable habitats for important calcifying species, including 43% reduction in habitat for tropical and subtropical coral reefs, up to 61% for polar pteropods, and 13% for coastal bivalves. By including these additional considerations, we suggest a revised boundary of 10% reduction from pre-industrial conditions more adequately prevents risk to marine ecosystems and their services; a benchmark which was surpassed by year 2000 across the entire surface ocean.

Read more:

https://onlinelibrary.wiley.com/doi/10.1111/gcb.70238

The ocean acidification “boundary” is based on Aragonite saturation. Aragonite is a form of calcium carbonate. Marine animals use Calcium Carbonate to form shells and coral structures. The theory is if Aragonite saturate drops below one (biased towards dissolution), shellfish and corals will find it difficult to build the calcium carbonate structures they depend on for survival.

Of course, determining habitable Argonite saturation levels is complicated by substantial natural variability.

… Ocean Ω conditions vary significantly across the globe, with levels in tropical regions being more than twice as high as those in polar regions (Feely et al. 2023; Jiang et al. 2015). These regional and seasonal gradients exists due to temperature-driven CO₂ solubility, enabling colder high-latitude waters to store more CO₂, along with other factors including circulation of carbon away from the surface into deeper waters, mineral inputs from land and freshwater dilution (Jiang et al. 2019; Orr et al. 2005). Marine life is exposed to such regionally varying gradients to which it has evolutionarily adapted (Vargas et al. 2022), resulting in a wide variability of observed responses to OA found in laboratory experiments. However, the envelope of the overall conditions experienced by organisms is also changing due to OA, which can make scaling up from single-species experiments to ecosystem predictions more complicated. This is particularly true when we consider the other challenges of scaling, including incubation effects, lack of natural variability and lack of adaptation and/or acclimation.

…

Aragonite saturation state (Ω_Arag) has emerged as a key indicator for OA, reflecting the precipitation/dissolution tendencies of CaCO₃, as well as its association with marine calcifiers. Consequently, the global mean surface Ω_Arag was chosen as the OA indicator in the planetary boundary assessments (Rockström et al. 2009). The boundary was set at 80% of the pre-industrial Ω_Arag value, that is, a 20% reduction from the pre-industrial surface ocean average. This level was chosen based on two criteria: first to keep high-latitude surface waters above Ω_Arag undersaturation; and second, to ensure adequate conditions for most warm-water coral reef systems (Rockström et al. 2009). …Read more: same link as above

Given the immense natural variability, and high genetic mobility of shellfish and corals, many of which reproduce by emitting vast numbers of microscopic larvae, setting the boundary condition at 80% of pre-industrial looks suspiciously like a guess.

Is there a way can we test this 80% boundary?

The solution of course, is to look at how fish and shelled creatures living in extreme environments cope with acidification. And there are few places more extreme than “champagne reefs”, patches of ocean where a constant source of volcanic gas keeps sea water supersaturated with CO2, well beyond anything we could ever achieve with anthropogenic emissions.

The fishes and the coral live happily in the CO2 bubble plume

Evidence trumps guesswork. Given proof that fish and shelled organisms can thrive in the most extraordinary ocean CO2 levels, and the likelihood many of those organisms have genetically compatible relatives which live outside natural CO2 saturated regions, perhaps it is time to revise that 80% boundary.

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

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.

From NoTricksZone

By Kenneth Richard

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.

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 tenths of a centimeter (0.16 cm) per year.

Image Source: **Frederikse et al., 2020** and **Frederikse et al., 2018**

The net melt of the Greenland ice sheet (GIS) is thought to have been the largest contributor to sea level rise in recent decades. But, to put the GIS change in context, the entire ice sheet melt contribution to sea level rise was just 1.2 total centimeters from 1992-2020 (Simonsen et al., 2021).

The Earth’s natural range of sea level rise rates, periodically reaching 4.7 cm per year, is thus 30 times greater in magnitude than the modern period’s (1900-2018) “anthropogenic” rate, which is 0.156 cm per year.

,Calibrating Holocene human environment interactions using ancient narratives The example of Ngurunderi in South Australia Herunterladen

,clim-jcli-d-17-0502.1 Herunterladen

,Geophysical Research Letters – 2021 – Simonsen – Greenland Ice Sheet Mass Balance 1992 2020 From Calibrated Radar Herunterladen

New Study: Large Atmospheric Pressure Swings May Explain Past Hothouse-Icehouse Climates, CO2 Levels

Atmospheric pressure may have been over 2.0 bar during the Jurassic, which may explain why Antarctica was a densely vegetated rainforest during that time.

From NoTricksZone

By Kenneth Richard

Atmospheric pressure may have been over 2.0 bar during the Jurassic, which may explain why Antarctica was a densely vegetated rainforest during that time.

It has long been understood that atmospheric pressure is one of the primary determinants of a planet’s temperature, with higher pressure (for example, Venus at 92 bar) yielding warmer climates due the increase in heat capacity with mass (Chemke et al., 2016, Chemke et al., 2017), and lower pressures (Mars at 0.006 bar, Earth at 1.0 bar) yielding cooler climates (Goldblatt et al., 2009, Sorokhtin et al., 2007).

Image Source: **Goldblatt et al., 2009**, **Sorokhtin et al., 2007**

What we know about the requisite physics for the aerodynamics of flight (e.g., how heavy is too heavy for lift-off) serves as a robust proxy for atmospheric pressure variations of the ancient past.

For instance, the “giant birds of the Miocene,” with wingspans of “6.5 m or more,” could not take flight with today’s air densities (Cannell, 2020). Knowing what we know about flight physics, a minimum air pressure of 1.3 bar “would have been necessary for these birds to fly.”

Using known size and flight physics for large-winged predators, scientists have concluded the Late Permian and Middle to Late Jurrassic may have had atmospheric pressures of over 2 bar (Cannell and Nel, 2023). This could explain the polar warmth allowing for an Antarctic rainforest near the South Pole ~90 million years ago (Klages et al., 2020).

A new study provides a visual for just how much pressure may have varied in the past, ranging from 0.5 bar ~350 Ma to ~2.5 bar 300 Ma, and then almost 2.0 bar ~100 Ma, or during the time of the dinosaurs. (See the chart provided.)

As mentioned, one salient effect of atmospheric pressure variations is the size of animal and plant species, with higher pressures and greater warmth yielding 60-70 m tall trees, giant wing-extended (volant) insects and birds, alligators and magnolias thriving at the North Pole during the Eocene (~50 Ma), etc.

An interesting section of the paper suggests that not only does a planet’s atmospheric pressure determine the global temperature and the size of its creatures, it also may determine atmospheric CO2 levels and how alkaline or acidic the oceans get.

As noted in another recent paper, global temperatures and atmospheric CO2 are significantly negatively correlated (r = -0.76) over the last 210 million years (Davis, 2023). Likewise, high CO2 levels are associated with cooling periods like the End Permian extinction event, but not with ocean acidification periods. This strongly suggests atmospheric CO2 levels are not the determinant of the oceans’ pH balance nor global temperature – as we are led to believe.

“Periods of high atmospheric CO2, such as the Devonian, but with non-acidic oceans…are of particular interest. Oceans absorb a large amount of CO2 (currently ~50 times that of the atmosphere) due to the relatively high solubility of this gas in seawater, as expressed by Henry’s constant. A reduction in atmospheric mass therefore leads to massive outgassing of fractionated CO2 into the air and relatively alkaline seas. This is seen in the Devonian, at the end Permian and the Triassic-Jurassic transition, as well as in many major cooling events that take place together with an increase in CO2. Conversely, an increase in atmospheric pressure increases absorption and leads to lower levels of atmospheric CO2, but more acidic seas.”

Scientists Selectively Reject CO2 Measurements That Do Not Align With The Human-Caused Narrative

Reconstructions of paleo CO2 levels openly rely on data derived from plant stomata. But when modern (1800s-present) CO2 measurements from stomata conflict with the narrative that humans drive CO2 levels, they are patently rejected.

From NoTricksZone

By Kenneth Richard

Scientists readily acknowledge plant stomata evidence from one location are “widely used as an effective tool for paleoenvironmental reconstructions” of global atmospheric CO2 from 1 to 150 million years ago (Badihagh et al., 2024).

For example, in a new study, 100-150 million-year-old stomata samples from Iran are shown to re-confirm global atmospheric CO2 levels hit 1,100 to 1,700 ppm during the Jurassic period. The authors proudly showcase how consistently their stomata-derived CO2 measurements compare to several other reconstructions reaching the same conclusion about past CO2 concentrations.

But that’s where the stomata-are-an-effective-paleo-CO2-measuring-tool perspective stops.

Whereas millions of years ago CO2 data derived from stomata were thought to be accurate, direct stomata measurements recorded in scientific papers from only a century ago – even the 1940s and 1950s – are regarded as not accurate. They must be rejected.

Dr. Ernst-Georg Beck’s compiled research with plant stomata-derived CO2 measurements was posthumously published in 2022. It’s an exhaustively-referenced paper detailing 97,404 direct near-ground measurement from 901 stations situated across the world, in both hemispheres. (This is very much unlike the ice core CO2 record in which only one continental location, Antarctica, is used; and yet this local record – contradicted by Greenland ice cores – is regarded as “global”.)

The research was recorded in 292 scientific papers (77 authors) covering stomata-derived direct CO2 measurements for the industrial era, 1800-1960.

These database compilations – ~60,000 global-scale measurements between the 1930s and 1950s alone – consistently show CO2 hit 380 ppm in 1943 and 372 ppm in 1950, with very small error margins after about 1870.

The currently accepted CO2 values for 1943 and 1950 are instead recorded as 310 ppm, and the 372 to 380 ppm values are not assumed to have been achieved until the mid-2000s. A data-driven portrayal of a decadal-scale decline in CO2 after the 1940s peak (shown in Fig. 24) contradicts the viewpoint that sharply rising anthropogenic CO2 emissions after 1945 led to tandemly increasing CO2 concentrations. Consequently, these direct CO2 measurements – tens of thousands of them from across the world – are rejected by the gatekeepers of the humans-did-it narrative.

Further, the stomata-derived CO2 values also indicate the temperature is the leading factor determining the CO2 concentration, with the CO2 changes correlationally (r = 0.67) lagging the temperature changes by about a year. This once again conflicts with the conclusion that CO2 levels are determined by anthropogenic emissions.

Another stomatal CO2 study published nearly 20 years ago also documents ±100 ppm CO2 changes over the last few centuries, with a peak of about 380 ppm in the 1940s. Like Beck’s work, this too must be rejected, as it doesn’t align with the human-caused angle.

Tag: CO2 levels

The Hill Pushes Discredited Ocean Acidity Scares

Like this:

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

Like this:

New Study: Large Atmospheric Pressure Swings May Explain Past Hothouse-Icehouse Climates, CO2 Levels

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Scientists Selectively Reject CO2 Measurements That Do Not Align With The Human-Caused Narrative

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