Ocean Acidification Research Articles

Single-Larva RNA Sequencing Reveals That Red Sea Urchin Larvae Are Vulnerable to Co-Occurring Ocean Acidification and Hypoxia.

Anthropogenic carbon dioxide emissions have been increasing rapidly in recent years, driving pH and oxygen levels to record low concentrations in the oceans. Eastern boundary upwelling systems such as the California Current System (CCS) experience exacerbated ocean acidification and hypoxia (OAH) due to the physical and chemical properties of the transported deeper waters. Research efforts have significantly increased in recent years to investigate the deleterious effects of climate change on marine species, but have not focused on the impacts of simultaneous OAH stressor exposure. Additionally, few studies have explored the physiological impacts of these environmental stressors on the earliest life stages, which are more vulnerable and represent natural population bottlenecks in organismal life cycles. The physiological response of the ecologically and commercially important red sea urchin (Mesocentrotus franciscanus) was assessed by exposing larvae to a variety of OAH conditions, mimicking the range of ecologically relevant conditions encountered currently and in the near future along the CCS. Skeleton dissolution, larval development, and gene expression show a response with clearly delineated thresholds that were related to OAH severity. Skeletal dissolution and the induction of Acid-sensing Ion Channel 1A at pH 7.94/5.70 DO mg/L provide particularly sensitive markers of OAH, with dramatic shifts in larval morphology and gene expression detected at the pH/DO transition of 7.71/3.71-7.27/2.72 mg/L. Experimental simulations that describe physiological thresholds and establish molecular markers of OAH exposure will provide fishery management with the tools to predict patterns of larval recruitment and forecast population dynamics.

Ocean acidification may contribute to recruitment failure for Bering Sea red king crab

We used semi-parametric Bayesian regression to determine whether ocean acidification or climate warming could explain declining productivity for southeast Bering Sea red king crab (Paralithodes camtchaticus). Negative effects of acidification explained ~21% of recruitment variability over 1980-2023, and ~45% since 2000. Ocean warming had a negligible effect in our analysis. Model-estimated annual mean bottom pH in the region has fallen from ~8.03 in 1980 to ~7.89 in 2023, approaching levels that reduce juvenile survival in laboratory studies. Improved model validation and better understanding of potential threshold effects on red king crab are needed to better understand the possible population-level acidification effect that we demonstrate.

Cloud to surface lightning activity in the Eastern Mediterranean Sea in the context of marine infrastructure safety

Lightning poses a significant threat to safety at sea and to marine infrastructure. Lightning protection systems are designed to withstand currents <200 kA; however, the theoretical limit of lightning intensity is 2–3 times higher. Lightning bolts with peak currents (PCs) greater than 100 kA, also known as Lightning Superbolts (LSBs) occur predominantly over the oceans, including the Eastern Mediterranean Sea. In this study we analyzed the cloud to sea surface lightning activity in the Israeli Mediterranean Exclusive Economic Zone (IMEEZ) based on two global lightning detection networks and Israeli national detection network. The main findings of this survey indicate that 0.4% (n = 557) of the lightning strikes in the IMEEZ have a PC strength significantly higher than 200 kA with median and average PCs of 248 and 298 ± 122 kA (±1STD), respectively. The spatial distribution of the LSBs in the IMEEZ is relatively homogeneous. Considering that seawater salinization and acidification may increase lightning intensity over the IMEEZ by 25% until 2050, it is clear that the risk to marine infrastructure in the region will increase and appropriate steps should be taken to upgrade their lightning protection systems to withstand a PC of 400 kA, which is one STD above the calculated mean.

A Review: Mechanisms of Ocean Acidification in the Context of Global Warming

Global warming stems mainly from the accumulation of greenhouse gases, which leads to higher atmospheric and ocean temperatures and has far-reaching impacts on marine systems. This paper focuses on the impact of global warming on the El Nio phenomenon and ocean acidification. There are significant changes in the frequency and intensity of El Nio events in the context of global warming, but the exact trends are uncertain. At the same time, the increase in carbon dioxide has led to ocean acidification, which poses a threat to the growth of marine organisms and the stability of ecosystems. An in-depth understanding of the role of El Nio and ocean acidification in climate change is therefore essential for the protection of marine ecosystems. For future marine ecological conservation, a comprehensive analysis of the climatic effects of El Nio and ocean acidification is essential. Only an in-depth study of these factors can lead to a more effective response to the ecological challenges posed by global warming.

Meta-Analysis of Larval Bivalve Growth in Response to Ocean Acidification and its Application to Sea Scallop Larval Dispersal in the Mid-Atlantic Bight

Ocean acidification, caused by increasing atmospheric carbon dioxide and coastal physical, biological, and chemical processes, is an ongoing threat to carbonate-utilizing organisms living in productive coastal shelves. Bivalves exposed to acidification have shown reduced growth, reproduction, and metabolic processes, with larval stages exhibiting the greatest susceptibility. Here, we compile results from published studies on larval bivalve growth responses to acidification to estimate a relationship between larval growth and seawater aragonite saturation state. We then apply this relationship to a larval dispersal individual-based model for Atlantic sea scallops (Placopecten magellanicus), an economically vital species in the Mid-Atlantic Bight that is historically under-studied in acidification research. To date, there have been no published studies on sea scallop larval response to ocean acidification. Model simulations allowed the identification of potential impacts of acidification on scallop success in the region. Results show that larval sea scallops that are sensitive to ocean acidification had a 17% lower settlement success rate and over 50% reduction in larval passage between major Mid Atlantic Bight fisheries habitats than those that are not sensitive to acidification. Additionally, temperature and ocean acidification interact as drivers of larval success, with aragonite saturation states > 3.0 compensating for temperature-induced mortality (> 19 ˚C) in some cases. This balance between drivers influences larval settlement success across spatial and interannual scales in the Mid Atlantic Bight.

Delayed onset of ocean acidification in the Gulf of Maine

The Gulf of Maine holds significant ecological and economic value for fisheries and communities in north-eastern North America. However, there is apprehension regarding its vulnerability to the effects of increasing atmospheric CO2. Substantial recent warming and the inflow of low alkalinity waters into the Gulf of Maine have raised concerns about the impact of ocean acidification on resident marine calcifiers (e.g. oysters, clams, mussels). With limited seawater pH records, the natural variability and drivers of pH in this region remain unclear. To address this, we present coastal water pH proxy records using boron isotope (δ11B) measurements in long-lived, annually banded, crustose coralline algae (1920–2018 CE). These records indicate seawater pH was low (~ 7.9) for much of the last century. Contrary to expectation, we also find that pH has increased (+ 0.2 pH units) over the past 40 years, despite concurrent rising atmospheric CO2. This increase is attributed to an increased input of high alkalinity waters derived from the Gulf Stream. This delayed onset of ocean acidification is cause for concern. Once ocean circulation-driven buffering effects reach their limit, seawater pH decline may occur swiftly. This would profoundly harm shellfisheries and the broader Gulf of Maine ecosystem.

Temporal trends of community and climate changes in the anthropocene: 21-year dynamics of four major functional groups in a rocky intertidal habitat along the Pacific coast of Japan

The influence of climate change on marine organism abundance has rarely been assessed (1) at the functional-group level; (2) simultaneously in major functional groups within the same ecosystem; (3) for &amp;gt;10 years; and (4) at metapopulation/community scales. A study simultaneously addressing these gaps would greatly enhance our understanding of the influence of climate change on marine ecosystems. Here, we analyzed 21 years of abundance data at the functional-group and species levels on a regional scale for four major functional groups (benthic algae, sessile animals, herbivorous benthos, and carnivorous benthos) in a rocky intertidal habitat along the northeastern Pacific coast of Japan. We aimed to examine the 21-year trends in regional abundance at both functional-group and species levels, plus their driving mechanisms and their dependence on species properties (thermal niche, calcification status, and vertical niche). Significant temporal trends in abundance were detected at functional-group levels for benthic algae (increasing) and herbivores and carnivores (both decreasing); they followed the temporal population trends of the dominant species. At species level, the metapopulation size of 12 of 31 species were increasing and 4 of those were decreasing, depending on the thermal niche and species calcification status. At both functional-group and species levels, temporal trends in abundance are caused by the direct or indirect influence of warming and ocean acidification. Comparing these results with community responses to marine heat waves in the same study area offered two implications: (1) long-term ecosystem changes associated with global warming will be unpredictable from the community response to marine heat waves, possibly owing to a lack of knowledge of the influence of calcifying status on species’ responses to climate change; and (2) thermal niches contribute greatly to predictions of the influence of warming on population size, regardless of the time scale.

Developing the ambition for action in the Ocean Decade to 2030

Abstract The ocean is vital for regulating climate, supporting biodiversity, and sustaining human livelihoods. However, as climate change accelerates ocean acidification, deoxygenation, warming, and biodiversity loss, the ocean’s ability to provide solutions is at risk. Addressing critical gaps in ocean science is essential, and the United Nations Decade of Ocean Science for Sustainable Development 2021–2030 (the “Ocean Decade”) seeks to bridge these gaps. Its transformative framework is built around 10 key challenges representing urgent needs for ocean knowledge. The Vision 2030 process, initiated in the Decade’s third year, refines these challenges, setting quantifiable success measures by 2030. Informed by contributions from around 150 experts and 10 White Papers, the Vision 2030 process highlights priorities such as actively considering Indigenous knowledge, co-designing innovative solutions, and enhancing investment in ocean science. This article introduces the insights of the Vision 2030 process, emphasizing the need for inclusive, coordinated action across the science–policy–society interface. It underscores the urgency of prioritizing ocean health and securing sustainable financing for ocean initiatives, particularly as Sustainable Development Goal (SDG) 14 remains the least funded SDG. Through advancing knowledge, fostering innovation, and promoting inclusivity, the Ocean Decade aims to protect ocean ecosystems and ensure a sustainable future for future generations.

The Role of Molluscs in Monitoring Marine Pollution and its Connection to Climate Change and ESG

Molluscs possess a unique capability to filter and remove pollutants from water, offering a natural and effective solution to combat marine pollution. Their filtration process not only enhances water quality but also mitigates the detrimental impacts of contaminants on marine ecosystems. As climate change introduces unprecedented challenges, the resilience of molluscs—particularly in adapting to rising temperatures and ocean acidification—highlights their critical role in sustaining marine ecosystem balance. This paper reviews the literature on molluscs from 1874 to 2024, as documented in the Scopus database, analyzing 5,757 publications retrieved on 8 March 2024. Five major insights emerged: (a) molluscs’ significant ecological role, (b) the potential of marine bivalves for ecosystem health and sustainability, (c) the importance of monitoring molluscs to address climate change, (d) the scarcity of studies linking molluscs to Environmental, Social, and Governance (ESG) practices, and (e) existing knowledge gaps. Understanding and monitoring mollusc populations are essential for advancing environmental stewardship, fostering social responsibility, and promoting sound governance. Integrating these aspects within business operations can support marine ecosystem resilience and reflect a commitment to the planet's and society's holistic well-being.

The IAEA Ocean Acidification International Coordination Centre Capacity Building Program: Empowering Member States to Address and Minimize the Impacts of Ocean Acidification

Ocean acidification (OA) is broadly recognized as a major problem for marine ecosystems worldwide, with follow-on effects to the economies of ocean-dependent communities. The urgent need to mitigate and minimize the impacts of OA is a scientific and political priority, as highlighted by the latest Intergovernmental Panel on Climate Change report (IPCC, 2022) and by the inclusion of OA as a target in the United Nations Sustainable Development Goals (SDG). In addition, over 20 years of strong scientific evidence on the impacts of OA provides compelling arguments for urgent CO2 mitigation. Reducing CO2 emissions will require ambitious regulatory and economic instruments, as well as effective systemic changes across governments and societies. It is critical to implement adaptation measures to minimize the impact of OA, among other key environmental stressors, as the mitigation process takes time, and the impacts of OA are already felt globally. Assessing the impacts of solutions and their potential implementations requires information at local scales, considering the variabilities in marine ecosystem responses to OA (e.g., local adaptation, species redundancies).

Balancing methane emission and alkalinity conservation: Insights from mineral amendments in coastal sediments.

With global climate warming and ocean acidification, mineral amendments in coastal areas have emerged as a promising strategy to bolster carbon sinks and alkalinity. However, most research has predominantly focused on carbon dioxide (CO2) absorption, with limited exploration of methane (CH4) reduction despite its more potent greenhouse effect. To address this gap, our study conducted a microcosm manipulative experiment employing coastal wetlands sediments to elucidate the regulatory effects of various mineral amendments on greenhouse gas emissions (including CO2 and CH4) and seawater alkalinity. The findings unveiled that olivine application effectively absorbed CO2, achieving a 175% reduction (-342.0mmolL-1h-1) in the late stage, while gypsum application significantly reduced CH4 by 53% (-6.06mmolL-1h-1) in the early stage. Nevertheless, applying gypsum led to a marked decrease in seawater alkalinity, potentially exacerbating ocean acidification and posing risks to marine ecosystems. Interestingly, the simultaneous application of both minerals showed promise in reducing CH4 emissions without compromising seawater alkalinity. This study presents a pioneering endeavor that contributes to the sustainable management of coastal wetlands and supports future initiatives at reducing CH4 emissions and alleviating ocean acidification.

Ocean Acidification Capacity Is Needed at All Levels to Develop a Multistakeholder Ocean Acidification Action Platform

Ocean Acidification Capacity Is Needed at All Levels to Develop a Multistakeholder Ocean Acidification Action Platform

Capacity Building with Volunteers: Divers and Boaters Collect Data on Southern California Bight

“The science we need for the ocean we want” (IOC, 2020) may be more science than we can afford unless we devise additional cost-​effective ways to produce it. Much of the science we need may require local knowledge and skills that are difficult to generate at scale. Global problems, such as ocean acidification, may be lessened by using site-specific solutions that require knowledge of local oceanography. Similarly, implementing solutions to local problems, such as pollution and fisheries sustainability, will require local knowledge and skills that cannot immediately be drawn from global capacity. Supplying the know-how for inexpensive staff and scientific gear to achieve these solutions may be part of capacity building and sharing in the UN Ocean Decade.

Physiological and behavioral responses of the Baltic clam Macoma balthica to a laboratory simulated CO2-leakage from a subseabed carbon storage site.

Carbon capture and storage in sub-seabed geological reservoirs is now officially included in the atmospheric CO2 emissions reduction policy and meets the agenda of Sustainable Development Goals (SDGs). Over the last few years biological risk assessment studies have delivered substantial empirical data on possible consequences of CO2 leakages from underwater storage sites on benthic systems. Current knowledge on Carbon Capture and Storage CCS associated risks is limited to marine systems. Yet there are multiple areas identified as suitable for carbon storage, but their hydrogeochemical features are so distinct that they should be studied as separate cases. Baltic Sea is one example of an area but is host to a unique - in a world scale - ecosystem with low salinity in combination with reduced oxygen availability in the benthic zone. Geological surveys have designated a potential storage site in the Southern Baltic Sea, namely the B3 oil field. Thus, this study focuses on biological effects of seawater acidification caused by a simulated CO2 leakage scenarios under laboratory conditions on a model macrobenthic in-faunal species. Baltic clams Macoma balthica were exposed to different environmental pH scenarios: pH7.7 (no leakage), pH7.0 (moderate hypercapnia) and pH6.3 (severe hypercapnia) in three independent experiments conducted with the use of a hyperbaric tank (Karl Eric Titank) mimicking hydrostatic pressure of 900kPa, relevant to conditions at the B3 field. Selected physiological aspects of the Baltic clam, such as survival, shell growth rate, morphometric condition and biochemical composition were investigated along with their behavioral responses, i.e. sediment burrowing activity. The results showed modest effects of hypercapnia on physiological performance of the clams that did not lead to greater mortality in neither of the tested leakage scenarios. Apart from high survival of the clams even in the lowest seawater pH (6.3) there were only little changes observed in the burrowing depth of the clams and biochemical composition of their soft tissues related to seawater acidification. The most evident physiological responses of the clams to prolonged hypercapnia (40days at pH6.3) were manifested in decreased shell growth.

Effects of ocean acidification and warming on apoptosis and immune response in the mussel Mytilus coruscus

Effects of ocean acidification and warming on apoptosis and immune response in the mussel Mytilus coruscus

Effect of CO2 driven seawater acidification on survival, growth, amino acid and fatty acid levels in the edible shrimp Litopenaeus vannamei

Effect of CO2 driven seawater acidification on survival, growth, amino acid and fatty acid levels in the edible shrimp Litopenaeus vannamei

The pollution and the ecological influence of chemical and industrial waste

Pollution from chemical and industrial wastes has far-reaching effects on ecosystems. Harmful substances such as heavy metals, persistent organic pollutants (e.g., polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs)), acid and alkali waste streams and other harmful substances enter the coastal and marine environments through rivers, sewage pipelines and other pathways, posing a serious threat to marine ecosystems and human health. Not only do these pollutants tend to accumulate in sediments, but they are also gradually amplified through the food chain, eventually reaching high concentrations in top predators and leading to biomagnification effects. In addition, ocean acidification and discharge of highly alkaline waste streams further affect carbonate-dependent marine organisms and disrupt the marine ecological balance. Understanding the environmental behavior of these pollutants and their ecological impacts is essential for developing effective pollution control and ecological protection measures.

Rising tide of ocean acidification

This comprehensive review explores the escalating environmental crisis of ocean acidification, primarily driven by anthropogenic carbon dioxide molecules (CO2) emissions. In this study, we employed a systematic methodology to collect and analyze literature relevant to ocean acidification. Our research involved an exhaustive search of databases such as PubMed, Web of Science, Google Scholar, and Mendeley to gather pertinent studies published up until 2024. In addition, we consulted secondary sources, including expert panel reports, to enhance the depth of our analysis. Socio-economic ramifications are profound, particularly for fisheries, tourism, and coastal communities that rely heavily on marine resources. This research underscores the potential for substantial exacerbates in these sectors, emphasizing the need for targeted policies and management strategies to mitigate the adverse effects of ocean acidification. By addressing these critical areas, the study informs stakeholders and supports the development of adaptive measures that can sustain local economies and preserve biodiversity in affected regions. The economic consequences could be substantial, exacerbating global social and economic disparities. Speculative considerations highlight the potential for significant global impacts and the urgent need for proactive, coordinated action. This review emphasizes the importance of continued research and monitoring to develop effective mitigation and adaptation strategies, underscoring the critical role of global cooperation and innovation in environmental management. This review aims to serve as a call to action, highlighting the urgency to preserve marine ecosystems and their services to humanity in the face of this growing environmental challenge.

One Ocean – a New Regulatory Solution to Climate Change

Global heating is pushing ocean temperatures to new heights, fuelling more frequent and intense storms, rising sea levels, and the salinization of coastal lands and aquifers. Untreated sewerage and wastewater containing toxic chemicals and millions of tons of plastic waste are flooding into coastal ecosystems, killing, or injuring fish, sea turtles, seabirds, and marine mammals, and making their way into the food chain and ultimately being consumed by humans. More than 17 million metric tons of plastic entered the world’s ocean in 2021, making up 85 per cent of marine litter, and projections are expected to double or triple each year by 2040, according to the latest Sustainable Development Goals (SDG) report. According to UN estimates, by 2050, there could be more plastic in the sea than fish unless action is taken.2 An innovative governance approach to ocean management is needed that builds ecosystem resilience to tackle the adverse effects of climate change and ocean acidification, and maintains and restores ecosystem integrity, including carbon cycling services. This paper discusses such an approach. Keywords Climate change, pollution, carbon capture, oceanic biosphere, continental linkages, regulatory models, governance.

Climate Change Impacts of Health Workers Without Safety Measures on Working Places

This study aims to explore the effects of climate change on health workers in Nepal, particularly in workplaces lacking safety measures. Climate change poses significant threats that can accumulate over time, leading to long-term changes in health and reliance on occupational safety and health (OSH). Factors such as rising ambient temperatures, air pollution, ultraviolet radiation exposure, and extreme weather events adversely affect OSH. Examples of climate change impacts include sea-level rise, warming oceans, shrinking ice sheets, glacial retreat, ocean acidification, and reduced snow cover. This research employs a review-based approach, utilizing systematic literature analysis to recommend pragmatic solutions. The researcher primarily employs deductive reasoning throughout the review process, employing in-depth archival analysis and intensive review strategies. The study finds that climate change affects organizational operations, leading to illnesses or injuries among health workers and increasing stress levels. Many health workers in Nepal operate without adequate safety measures; for example, healthcare personnel often lack gloves and masks, construction workers do not use protective gear, and farmers apply pesticides without safety equipment. These unsafe practices expose workers to respiratory and cardiovascular diseases, reproductive dysfunctions, vector[1]borne diseases, and other climate-sensitive health risks. The findings underscore the urgent need for improved occupational safety measures to protect health workers from the adverse effects of climate change.