YouTube video by NOAA_AOML

The OA CoP recently participated in The Ocean in a High-CO2 World Symposium in Wellington, New Zealand, and we were delighted to connect with both our Canadian community and international collaborator...

As climate change drives more carbon dioxide into the oceans, seawater is becoming increasingly acidic, a growing threat to shell-building creatures such as clams, oysters, and mussels. Now, researchers at the University of California, Davis have uncovered why a simple practice used for generations by Indigenous communities may help these animals survive. In a study published in Biogeosciences, scientists found that adding crushed shells, known as shell hash, to beach sediments can reduce local acidity and create conditions that help young clams grow stronger shells. The research not only showed physical benefits for the clams but also revealed something happening at a deeper biological level: shell hash appeared to shield the animals from the genetic stress normally triggered by acidified seawater. Ocean acidification is caused by ocean water absorbing atmospheric carbon dioxide. When the level of acidity increases, it becomes harder for animals that build shells to do so. In addition to requiring more energy to produce their shells, as the levels of acidity increase, the ocean may start to break down some of the shell materials. Sea snail shells dissolve in increasingly acidified oceans, study shows Young animals are thought to be especially vulnerable. To investigate whether shell hash...

Indigenous people have long added crushed shells to sand to keep coastal ecosystems healthy. A UC Davis study reveals why it works and how it helps buffer clams, oysters and mussels from ocean acidification.

For a young clam, growing a shell takes energy. As the ocean absorbs more carbon dioxide and becomes more acidic, that job gets harder. A new lab experiment suggests that mixing crushed shells into the sand can ease some of that strain. The practice has long been part of how some Indigenous communities care for clam beds. Young clams in acidified seawater showed substantial changes in gene activity. When researchers added crushed shells to their sand, those changes largely disappeared, and their gene activity looked much like that of clams in regular seawater. Hannah Kempf led the study as a doctoral student in the Department of Earth and Planetary Sciences at the University of California, Davis. Her team raised the clams in buckets at Bodega Marine Laboratory for 90 days. Why acidity matters The ocean’s surface has become about 30% more acidic since the industrial era began. As seawater absorbs carbon dioxide released by people, it loses some of the chemical building blocks that animals need to make shells. That means clams, oysters and mussels must spend more energy building their shells. Acidic water can also dissolve them. In the early 2000s, coastal acidification contributed to widespread losses at Pacific...

As climate change drives more carbon dioxide into the oceans, seawater is becoming increasingly acidic, a growing threat to shell-building creatures such as clams, oysters, and mussels. Now, researchers at the University of California, Davis have uncovered why a simple practice used for generations by Indigenous communities may help these animals survive. In a study published in Biogeosciences, scientists found that adding crushed shells, known as shell hash, to beach sediments can reduce local acidity and create conditions that help young clams grow stronger shells. The research not only showed physical benefits for the clams but also revealed something happening at a deeper biological level: shell hash appeared to shield the animals from the genetic stress normally triggered by acidified seawater. Ocean acidification is caused by ocean water absorbing atmospheric carbon dioxide. When the level of acidity increases, it becomes harder for animals that build shells to do so. In addition to requiring more energy to produce their shells, as the levels of acidity increase, the ocean may start to break down some of the shell materials. Sea snail shells dissolve in increasingly acidified oceans, study shows Young animals are thought to be especially vulnerable. To investigate whether shell hash...

Dates: 30 November – 11 December 2026 Location: IAEA Marine Environment Laboratories, Monaco. Deadline for application through InTouch+ platform: 6 November 2026 The Winter School is organized by the ...

Dates: 30 November – 11 December 2026 Location: IAEA Marine Environment Laboratories, Monaco. Deadline for application through InTouch+ platform: 6 November 2026 The Winter School is organized by the ...

As the world's ocean acidification community gathers in Wellington, Pacific governments, scientists and finance institutions lay out how the region is turning science into climate action ahead of COP3...

Through a combination of water sample collection and half-hour measurements by autonomous data probes, we recorded dissolved nutrients, ocean temperature, salinity, ocean pH and chlorophyll a in the surface waters spanning the past 24 years at Tatoosh Island, Makah Tribal Nation, Washington, USA (48o 23’N, 124o 44’W), a site that has been the subject of long-term ecological study for more than half a century5,7,29. As we have reported for shorter data durations5,7, pH at this site has declined persistently over the study period at rates far faster (−0.027 units year−1, r2 = 0.727, P < 0.001, n = 21 annual averages derived from 77,891 measurements) than predicted30 based on equilibrial dynamics between the ocean and the atmosphere under measured increases in global atmospheric CO2 concentrations (Fig. 2a). Local areas of rapid pH decline such as those at our site provide an early window into broader ocean responses predicted by the turn of the century. Under elevated CO2 regimes, we might expect three hypothetical patterns of change to emerge in silicate availability and phytoplankton chlorophyll (Fig. 1). First, higher inorganic carbon availability could serve to fertilize primary production31, thereby depleting other essential elements for phytoplankton growth, including Sisol. Second, reduced Sisol...

YouTube video by Chugach Regional Resources Commission

The local organising committee warmly invites you to join us for The 6th International Symposium on the Ocean in a High CO₂ World in Wellington, New Zealand, at Tākina Convention & Exhibition Centre.