More Like this

1. Diel and tidal pCO2 × O2 fluctuations provide physiological refuge to early life stages of a coastal forage fish

   https://doi.org/10.1038/s41598-019-53930-8  

   Cross, Emma L.; Murray, Christopher S.; Baumann, Hannes (December 2019, Scientific Reports)

   null (Ed.)

   Abstract Coastal ecosystems experience substantial natural fluctuations in p CO 2 and dissolved oxygen (DO) conditions on diel, tidal, seasonal and interannual timescales. Rising carbon dioxide emissions and anthropogenic nutrient input are expected to increase these p CO 2 and DO cycles in severity and duration of acidification and hypoxia. How coastal marine organisms respond to natural p CO 2  × DO variability and future climate change remains largely unknown. Here, we assess the impact of static and cycling p CO 2  × DO conditions of various magnitudes and frequencies on early life survival and growth of an important coastal forage fish, Menidia menidia . Static low DO conditions severely decreased embryo survival, larval survival, time to 50% hatch, size at hatch and post-larval growth rates. Static elevated p CO 2 did not affect most response traits, however, a synergistic negative effect did occur on embryo survival under hypoxic conditions (3.0 mg L −1 ). Cycling p CO 2  × DO, however, reduced these negative effects of static conditions on all response traits with the magnitude of fluctuations influencing the extent of this reduction. This indicates that fluctuations in p CO 2 and DO may benefit coastal organisms by providing periodic physiological refuge from stressful conditions, which could promote species adaptability to climate change. 

   more » « less
2. Delayed onset of ocean acidification in the Gulf of Maine

   https://doi.org/10.1038/s41598-024-84537-3  

   Stewart, Joseph A; Williams, Branwen; LaVigne, Michèle; Wanamaker, Alan D; Strong, Aaron L; Jellison, Brittany; Whitney, Nina M; Thatcher, Diana L; Robinson, Laura F; Halfar, Jochen; et al (December 2025, Scientific Reports)

   Abstract 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. 

   more » « less
3. Climate Change Implications for Tidal Marshes and Food Web Linkages to Estuarine and Coastal Nekton

   https://doi.org/10.1007/s12237-020-00891-1  

   Colombano, Denise D.; Litvin, Steven Y.; Ziegler, Shelby L.; Alford, Scott B.; Baker, Ronald; Barbeau, Myriam A.; Cebrián, Just; Connolly, Rod M.; Currin, Carolyn A.; Deegan, Linda A.; et al (January 2021, Estuaries and Coasts)

   null (Ed.)

   Abstract Climate change is altering naturally fluctuating environmental conditions in coastal and estuarine ecosystems across the globe. Departures from long-term averages and ranges of environmental variables are increasingly being observed as directional changes [e.g., rising sea levels, sea surface temperatures (SST)] and less predictable periodic cycles (e.g., Atlantic or Pacific decadal oscillations) and extremes (e.g., coastal flooding, marine heatwaves). Quantifying the short- and long-term impacts of climate change on tidal marsh seascape structure and function for nekton is a critical step toward fisheries conservation and management. The multiple stressor framework provides a promising approach for advancing integrative, cross-disciplinary research on tidal marshes and food web dynamics. It can be used to quantify climate change effects on and interactions between coastal oceans (e.g., SST, ocean currents, waves) and watersheds (e.g., precipitation, river flows), tidal marsh geomorphology (e.g., vegetation structure, elevation capital, sedimentation), and estuarine and coastal nekton (e.g., species distributions, life history adaptations, predator-prey dynamics). However, disentangling the cumulative impacts of multiple interacting stressors on tidal marshes, whether the effects are additive, synergistic, or antagonistic, and the time scales at which they occur, poses a significant research challenge. This perspective highlights the key physical and ecological processes affecting tidal marshes, with an emphasis on the trophic linkages between marsh production and estuarine and coastal nekton, recommended for consideration in future climate change studies. Such studies are urgently needed to understand climate change effects on tidal marshes now and into the future. 

   more » « less
4. The Impacts of Ocean Acidification on Marine Ecosystems and Reliant Human Communities

   https://doi.org/10.1146/annurev-environ-012320-083019  

   Doney, Scott C.; Busch, D. Shallin; Cooley, Sarah R.; Kroeker, Kristy J. (October 2020, Annual Review of Environment and Resources)

   Rising atmospheric carbon dioxide (CO 2 ) levels, from fossil fuel combustion and deforestation, along with agriculture and land-use practices are causing wholesale increases in seawater CO 2 and inorganic carbon levels; reductions in pH; and alterations in acid-base chemistry of estuarine, coastal, and surface open-ocean waters. On the basis of laboratory experiments and field studies of naturally elevated CO 2 marine environments, widespread biological impacts of human-driven ocean acidification have been posited, ranging from changes in organism physiology and population dynamics to altered communities and ecosystems. Acidification, in conjunction with other climate change–related environmental stresses, particularly under future climate change and further elevated atmospheric CO 2 levels, potentially puts at risk many of the valuable ecosystem services that the ocean provides to society, such as fisheries, aquaculture, and shoreline protection. This review emphasizes both current scientific understanding and knowledge gaps, highlighting directions for future research and recognizing the information needs of policymakers and stakeholders. Expected final online publication date for the Annual Review of Environment and Resources, Volume 45 is October 19, 2020. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates. 

   more » « less
5. Variable exposure to multiple climate stressors across the California marine protected area network and policy implications

   https://doi.org/10.1093/icesjms/fsad120  

   Hamilton, S L; Kennedy, E G; Zulian, M; Hill, T M; Gaylord, B; Sanford, E; Ricart, A M; Ward, M; Spalding, A K; Kroeker, K (July 2023, ICES Journal of Marine Science)

   Coll, Marta (Ed.)

   Abstract The efficacy of marine protected areas (MPAs) may be reduced when climate change disrupts the ecosystems and human communities around which they are designed. The effects of ocean warming on MPA functioning have received attention but less is known about how multiple climatic stressors may influence MPAs efficacy. Using a novel dataset incorporating 8.8 million oceanographic observations, we assess exposure to potentially stressful temperatures, dissolved oxygen concentrations, and pH levels across the California MPA network. This dataset covers more than two-thirds of California’s 124 MPAs and multiple biogeographic domains. However, spatial-temporal and methodological patchiness constrains the extent to which systematic evaluation of exposure is possible across the network. Across a set of nine well-monitored MPAs, the most frequently observed combination of stressful conditions was hypoxic conditions (<140 umol/kg) co-occurring with low pH (<7.75). Conversely, MPAs exposed most frequently to anomalously warm conditions were less likely to experience hypoxia and low pH, although exposure to hypoxia varied throughout the 2014–2016 marine heatwaves. Finally, we found that the spatial patterns of exposure to hypoxia and low pH across the MPA network remained stable across years. This multiple stressor analysis both confirms and challenges prior hypotheses regarding MPA efficacy under global environmental change. 

   more » « less