Ocean Acidification
Transgressed: the 2025 Planetary Health Check identifies ocean acidification as the seventh planetary boundary to be breached, newly crossed in that assessment.
Owners voting their values can deliver most of the outcome.
Why shareholder democracy is pivotal
Ocean acidification is caused by seawater absorbing the carbon dioxide that fossil fuel burning, cement production, and deforestation have added to the atmosphere, roughly two trillion tons since the Industrial Revolution according to NOAA. The only mitigation is therefore cutting CO2 emissions. That lever runs through the identical set of listed fossil fuel producers, utilities, cement makers, automakers, and financing banks documented for the climate boundary. It faces the identical political obstacle: InfluenceMap finds 39 percent of assessed US companies and industry associations lobbying against IPCC-aligned climate policy. Unlike the climate dimension, there is no separate adaptation pathway that governments could pursue instead. The chemistry responds only to atmospheric CO2, which makes corporate conduct and corporate lobbying the whole causal chain that human action can touch. The corresponding SDG target bundles state-led scientific cooperation and impact management with mitigation, and so leans more on governments; this boundary is defined by the CO2 chemistry alone. Owner action at emitters is one of the few available levers, and it is already in use. Owners have secured majority votes on emissions targets and lobbying alignment at ConocoPhillips and Phillips 66. As You Sow's Road to Zero Emissions scorecard grades the largest U.S. companies on the CO2 reductions that determine ocean chemistry. State-owned emitters remain outside direct reach, but they operate within demand and policy conditions that listed companies largely set. Owners voting their values can deliver most of this outcome.
How this was scoredPivotal
Pivotal. Owners voting their values can deliver most of the outcome.
We have not yet written down the two answers behind this rating. Recording them on every item, so a reader can check the reasoning and not only the conclusion, is work in progress.
Every rating is the higher of two answers, one for what companies do and one for what they spend to stop the outcome, because the same vote reaches both. See the full method.
Sources
- Seven of nine planetary boundaries now breached - ocean acidification joins the danger zone, Potsdam Institute for Climate Impact Research, 2025-09-24
- The Future of Ocean Acidification, NOAA Pacific Marine Environmental Laboratory, 2019-12-19
- US Corporate Climate Advocacy Going Into 2025, InfluenceMap, 2024-12
- In historic votes, shareholders demand strong climate action from the U.S. oil and gas industry, Climate Action 100+, 2021-05-12
- 55 Companies Ranked on Net Zero Emissions Reductions, As You Sow, 2022-03-03
What civil society organizations are helping owners on this
Files climate resolutions at fossil fuel producers and grades the 100 largest U.S. companies on CO2 reduction through its Road to Zero Emissions scorecard.
Coordinates investor engagement with the largest CO2 emitters asking them to reduce emissions, improve climate governance and strengthen disclosure, and benchmarks progress annually.
Exxon Mobil Corp. company assessment, Climate Action 100+, 2025-10
7 campaigns on record
Reduce greenhouse gas emissions across the value chain, set short-term targets, disclose a decarbonization strategy and align policy engagement with the Paris Agreement.
Result: Benchmark assessment as of June 2025 finds net zero ambition and medium and long-term targets in place but no short-term targets, inadequate Scope 3 coverage, no disclosed decarbonization strategy and no climate policy alignment commitment
Exxon Mobil Corp. company assessment, Climate Action 100+, 2025-10
Report how declining fossil fuel demand under the IEA net zero 2050 pathway would affect the company's finances.
Result: 52 percent in favor
Shareholders win majority support for climate proposals at Exxon, Chevron, Grist, 2022-05
Adopt a policy restricting the banks from lending to and underwriting new oil and gas exploration and development projects.
Result: Citigroup 12.8%, Bank of America 11%, Wells Fargo 11% of shareholders voted in favor The proposal was precatory (advisory and non-binding).
we found no documented change at any of the three banks directly attributed to this 2022 vote
Shareholder proposals on climate fail to gain traction at 3 major banks, Banking Dive
Set Paris-Agreement-consistent emissions targets; at ExxonMobil specifically, set targets covering Scope 3 emissions from the use of its products (about 90% of the company's total emissions), which the company had so far declined to do.
Result: 33% of Chevron shareholders and 28% of ExxonMobil shareholders voted in favor The proposal was precatory (advisory and non-binding).
we found no documented change at either company directly attributed to this specific 2022 vote
Set and disclose a plan to reduce all of Chevron's greenhouse gas emissions, including Scope 3 emissions from the use of its products, in line with the Paris Agreement.
Result: 61% of shareholders voted in favor The proposal was precatory (advisory and non-binding).
we found no documented change at Chevron directly attributed to this specific 2021 vote
Set emission reduction targets covering the greenhouse gas emissions of the company's operations and its energy products (Scope 1, 2 and 3).
Result: 58 percent in favor
Company established climate goals following the shareholder vote, according to Follow This.
58% of ConocoPhillips shareholders vote for Follow This climate proposal, Follow This, 2021-05
Engine No. 1, an activist investor holding about 0.02% of Exxon's shares, nominated an independent slate of board candidates and asked shareholders to replace directors with people who had experience managing a profitable transition in the energy industry, arguing the existing board lacked the expertise and independence to manage climate-related business risk and to spend capital with discipline.
Result: Engine No. 1's nominees won 3 of ExxonMobil's 12 board seats (Gregory Goff, Kaisa Hietala, and Alexander Karsner), per ExxonMobil's own June 2, 2021 announcement of preliminary results. Major pension funds including CalPERS, CalSTRS, and the New York State Common Retirement Fund backed the dissident slate.
One year on, ExxonMobil increased Scope 3 emissions disclosure, set more ambitious Scope 1 and 2 targets, shifted from a planned 25% production growth to holding production steady, and added board members with energy-transition experience; Engine No. 1's own team characterized the underlying long-term business strategy, continued heavy spending on new fossil fuel projects (about $30-35 billion a year), and lobbying posture as largely unchanged.
Engine No. 1 wins at least 2 Exxon board seats as activist pushes for climate strategy change, CNBC
How this rating was made
Every item on every one of our maps is read against one question: how far does this depend on the people who own companies voting their values? We answer it twice, once for what companies do and once for what they spend to stop the outcome, and take whichever answer is higher, since the same vote reaches both. The score carries its reasoning and its sources so that a reader can check it rather than take it.
- Pivotal. Owners voting their values can deliver most of the outcome.
- Necessary. Owners remove an obstacle nothing else removes, and others must also act.
- Helpful. Owners voting their values help, and others carry most of it.
- Independent. This moves without owners. Other levers carry it.
The advocacy record on this page holds only what a source we opened says happened. Where we searched and found nothing, the page says so rather than leaving a silence. Where a campaign names a filer the source does not name, it says that too. Ratings are ours; the list of subjects is Doughnut Economics's, and we link to their original.
How we score dependency, in full.