{"id":382772,"date":"2025-06-11T17:55:36","date_gmt":"2025-06-11T15:55:36","guid":{"rendered":"https:\/\/climatescience.press\/?p=382772"},"modified":"2025-06-11T17:55:38","modified_gmt":"2025-06-11T15:55:38","slug":"the-hill-pushes-discredited-ocean-acidity-scares","status":"publish","type":"post","link":"https:\/\/climatescience.press\/?p=382772","title":{"rendered":"The Hill Pushes Discredited Ocean Acidity Scares"},"content":{"rendered":"\n
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From Watts Up With That?<\/a><\/p>\n\n\n\n

Essay by<\/strong> Eric Worrall<\/a><\/p>\n\n\n\n

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.<\/p>\n\n\n\n

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\u2018Ticking time bomb\u2019: Ocean acidity crosses vital threshold, study finds<\/p>\n\n\n\n

BY SAUL ELBEIN<\/a> \u2013 06\/09\/25 11:24 AM ET<\/p>\n\n\n\n

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

Nearly two-thirds of the ocean below 200 meters, or 656 feet, as well as nearly half of that above, have breached \u201csafe\u201d levels of acidity, according to findings<\/a> published on Monday in Global Change Biology.<\/p>\n<\/blockquote>\n\n\n\n

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The fall in ocean pH is \u201ca ticking time bomb for marine ecosystems and coastal economies,\u201d<\/strong> Steve Widdicombe, director of science at the United Kingdom\u2019s Plymouth Marine Laboratory (PML), said<\/a> in a statement.<\/p>\n\n\n\n

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

\u2026Read more:\u00a0<\/p>\n\n\n\n

https:\/\/thehill.com\/policy\/equilibrium-sustainability\/5340239-ocean-acidity-study-climate-change-carbon\/<\/a><\/p>\n<\/blockquote>\n\n\n\n

The referenced study;<\/p>\n\n\n\n

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Ocean Acidification: Another Planetary Boundary Crossed<\/strong><\/p>\n\n\n\n

Helen S. Findlay<\/a>, Richard A. Feely<\/a>, Li-Qing Jiang<\/a>, Greg Pelletier<\/a>, Nina Bednar\u0161ek<\/a><\/p>\n\n\n\n

First published: 09 June 2025<\/p>\n\n\n\n

Funding:<\/strong> This work was supported by European Space Agency, AO\/1-10757\/21\/I-DT. Natural Environment Research Council, NE\/X006271\/1. NOAA\u2019s 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.<\/p>\n\n\n\n

ABSTRACT<\/strong><\/p>\n\n\n\n

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\u2009m) 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.<\/p>\n\n\n\n

Read more:\u00a0<\/p>\n\n\n\n

https:\/\/onlinelibrary.wiley.com\/doi\/10.1111\/gcb.70238<\/a><\/p>\n<\/blockquote>\n\n\n\n

The ocean acidification \u201cboundary\u201d 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.<\/p>\n\n\n\n

Of course, determining habitable Argonite saturation levels is complicated by substantial natural variability.<\/p>\n\n\n\n

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\u2026 Ocean \u03a9 conditions vary significantly across the globe, with levels in tropical regions being more than twice as high as those in polar regions<\/strong> (Feely et al. 2023<\/a>; Jiang et al. 2015<\/a>). These regional and seasonal gradients exists due to temperature-driven CO2<\/sub> solubility, enabling colder high-latitude waters to store more CO2<\/sub>, along with other factors including circulation of carbon away from the surface into deeper waters, mineral inputs from land and freshwater dilution<\/strong> (Jiang et al. 2019<\/a>; Orr et al. 2005<\/a>). Marine life is exposed to such regionally varying gradients to which it has evolutionarily adapted (Vargas et al. 2022<\/a>), 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.<\/p>\n\n\n\n

\u2026<\/p>\n\n\n\n

Aragonite saturation state (\u03a9Arag<\/sub>) has emerged as a key indicator for OA, reflecting the precipitation\/dissolution tendencies of CaCO3<\/sub>, as well as its association with marine calcifiers. Consequently, the global mean surface \u03a9Arag<\/sub> was chosen as the OA indicator in the planetary boundary assessments (Rockstr\u00f6m et al. 2009<\/a>). The boundary was set at 80% of the pre-industrial \u03a9Arag<\/sub> value, that is, a 20% reduction from the pre-industrial surface ocean average.<\/strong> This level was chosen based on two criteria: first to keep high-latitude surface waters above \u03a9Arag<\/sub> undersaturation; and second, to ensure adequate conditions for most warm-water coral reef systems (Rockstr\u00f6m et al. 2009<\/a>). \u2026Read more: same link as above<\/a><\/p>\n<\/blockquote>\n\n\n\n

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.<\/p>\n\n\n\n

Is there a way can we test this 80% boundary?<\/strong><\/p>\n\n\n\n

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 \u201cchampagne reefs\u201d, 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.<\/p>\n\n\n\n

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The fishes and the coral live happily in the CO2 bubble plume<\/a><\/blockquote>