Scientists are sounding the alarm over a worsening situation in Earth’s oceans and freshwater systems, according to a new study that warns of “irreversible” changes our planet could be facing.
New research led by the Scripps Institution of Oceanography at UC San Diego has revealed the rapid disappearance of oxygen from bodies of sea and fresh water, leading to environmental changes that could endure for centuries if left unmitigated.
The new study, which appeared in the journal Limnology and Oceanography, argues that widespread aquatic deoxygenation—reduced levels of dissolved oxygen in oceans and coastal waters, lakes, rivers, and streams—is increasingly becoming a problem, and one that influences nine other crucial environmental processes.
These processes are all included in what is known as the Planetary Boundaries framework, a science-based tool that outlines the requirements of a safe operating space for humanity. Introduced in 2009 by Earth system scientists led by Johan Rockström, this framework identifies nine critical environmental processes that regulate Earth’s stability.
Specifically, the nine planetary boundaries outlined in this framework are climate change, biosphere integrity, land use changes, biogeochemical flow of nutrients, ocean acidification, freshwater changes, atmospheric aerosol loading, stratospheric ozone depletion, and pollution.
Now, the Scripps researchers behind the recent study say they believe dissolved oxygen levels should also be formally included in this framework.
Aquatic Deoxygenation is a Growing Concern
Erica Ferrer, a Scripps Oceanography alumna and current postdoctoral scholar at UC Santa Barbara’s National Center for Ecological Analysis and Synthesis and lead author of the new study, says that her team’s work “is designed to elevate the profile of aquatic deoxygenation as a global threat and show that it does not operate in isolation.”
“The health and stability of our planet depends on the health and stability of aquatic ecosystems, which need oxygen to function normally,” Ferrer said.
Driving this growing problem, the new research says, is the excessive influx of nutrient pollution into water bodies, as well as anthropogenic warming, and changes occurring in natural ventilation systems within deep ocean waters.
With depleting oxygen levels scientists are seeing, longer-term changes to chemical and biological processes that regulate our planet’s climate are expected to occur. The decline, Ferrer and her colleagues argue, is also likely to impact a diverse range of aquatic organisms and ecosystems.
Even ocean mammals that acquire air at the surface are likely to be impacted, since deoxygenation can either cause the relocation or outright depletion of the organisms that make up their diets. This, in addition to causing severe damage to habitats and alterations to the food webs they depend on.
Ferrer and her colleague, study co-author and Scripps biological oceanographer Lisa Levin, are hopeful that their findings will encourage a deeper level of engagement on the potential ramifications of aquatic oxygen loss, and how other environmental challenges outlined in the planetary boundaries framework can act as multipliers, rather than separate existential concerns.
“Adding aquatic deoxygenation to the Planetary Boundaries framework will help us understand its impacts on Earth system stability,” Ferrer said in a statement, adding that mitigation of ocean deoxygenation impacts “represents a critical component of maintaining biodiversity and climate.”
Levin, Ferrer, and their colleagues’ study, “Abundant interactions and feedbacks between aquatic deoxygenation and the other planetary boundaries suggest ‘unsafe’ levels of oxygen loss with far‐reaching impacts,” appeared in the journal Limnology and Oceanography on June 30, 2026.
Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. A longtime reporter on science, defense, and technology with a focus on space and astronomy, he can be reached at micah@thedebrief.org. Follow him on X @MicahHanks, and at micahhanks.com.