Archive Page 160

Peaceful Uses of Nuclear Technology: a powerful tool for a better world

Published 18 August 2022 Web sites and blogs Closed

The Nuclear Non-Proliferation Treaty (NPT) does more than offer a foundation to prevent the spread of nuclear weapons. It is also a powerful instrument to promote peaceful uses of nuclear energy, science, and technology around the world.

Since the NPT came into force more than 50 years ago, cooperation on the peaceful uses of nuclear technology has grown tremendously. Today, thanks to the framework provided by Article IV of the NPT, peaceful nuclear applications are improving the lives of people around the world. The widespread and diverse benefits of peaceful uses of science are an enormous success of the NPT and the nuclear nonproliferation regime.

The International Atomic Energy Agency (IAEA) is a key facilitator in the development and delivery of the peaceful uses of nuclear energy and technology. The United States is by far the largest contributor to IAEA peaceful use programs, providing more than $395 million since 2015, including more than $93 million to its Peaceful Uses Initiative (PUI), established in 2010 to attract additional funding and support projects that expand and complement the IAEA’s technical assistance activities.

Contributions to the Peaceful Uses Initiative have enhanced the capabilities of more than 150 IAEA Member States to promote human health, water resource management, food security, sustainable development, and clean energy while responding to emerging and unanticipated needs.

Nuclear technology plays a pivotal role in addressing the world’s energy, health, and agricultural needs. Nuclear innovation is also a key tool used to support the UN Sustainable Development Goals — a series of 17 global objectives established as a “blueprint” for a more sustainable future. Since the UN’s announcement of the Sustainable Development Goals in 2015, the IAEA has made use of the resources provided by the Peaceful Uses Initiative to target critical development needs globally.

Listed below are a few of the UN Sustainable Development Goals that U.S. contributions to the Peaceful Uses Initiative (PIU) have supported:

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Sustainable Development Goal #13: Protecting the Environment

Graphic text against a dark green background: "Since 2010, U.S. PUI contributions of $37 million to the IAEA have helped address climate change. #13: Climate action."

U.S. contributions in support of the PUI have funded regional projects to better understand the effects of climate change. Researchers use nuclear and isotopic techniques to collect data and monitor how climate change affects the environment and to identify sources of pollutants and greenhouse gas emissions. In addition to helping countries understand and adapt to the effects of climate change, the IAEA promotes nuclear power as a source of low-carbon energy and an important tool to reduce greenhouse gas emissions.

Sustainable Development Goal #14: Marine Conservation

Graphic text against a blue background: "Since 2010, U.S. PUI contributions of $16 million to the IAEA have supported the ocean and marine conservation. #14: Life below water.

Nuclear technology is used to trace pollution and harmful algal blooms in marine waters, evaluate the causes of coastal dead zones, monitor marine environmental effects, and promote global actions against ocean acidification. The U.S strongly supports the IAEA’s efforts to conserve ocean, sea, and marine resources.

The United States is committed to advancing innovation and international cooperation in the field of nuclear science and technology through the IAEA’s Peaceful Uses Initiative and in direct support of the UN Sustainable Development Goals. We will continue to uphold the NPT as the cornerstone of the nuclear nonproliferation regime that enables nuclear technology to improve the lives of so many people throughout the world.

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Ocean conservation success stories offer hope and inspiration

Published 18 August 2022 Art , Web sites and blogs Closed

New technologies and research are helping solve problems such as plastic pollution, bycatch and ocean acidification.

(Illustrations by Feng Chen For The Washington Post)

It’s easy to take the ocean for granted. The deep blue is crucial to things we do every day without thinking. We breathe. We eat and drink. We buy something that’s made far from where we live. The ocean contributes to all those things. Not thinking about what the ocean does for us would be okay if its gifts were limitless. But they are not. And the actions of humans — nearly 8 billion of us — are threatening resources we can’t do without.

Thankfully, a growing number of people are focused on safeguarding the ocean. Scientists, lawmakers, businesses and nonprofit groups are among those raising awareness of problems such as plastic pollution, bycatch and ocean acidification. They aren’t only highlighting problems, however. They are developing solutions. Small success stories are building hope and encouraging more people to get involved.

We created a special collection of KidsPost stories because we know that when you think about the ocean, you realize how valuable it is. We have proof. Readers recently answered our request for short ocean appreciations, several of which we feature below. Reflecting is a good first step. We hope the additional stories and photos deepen your understanding of the ocean’s problems and inspire you to be part of the solutions.

Reflections by young writers

What I appreciate most about the ocean is the diversity of life it supports, from enormous blue whales to tiny, but ever so important, corals. I love the beauty, architecture and liveliness of all the animals, plants and others who dwell under the sea.

— Brice Claypoole, 14, Longboat Key, Florida

Treasure, transportation and food. All of these good things come from the ocean. The ocean lets us explore and express ourselves. It gives us food and all of these amazing things that come from the ocean. It allows us to show the world what we can do together!

— Owen Bairley, 9, Fredericksburg, Virginia

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Sustainable EV Tour arrives in Ireland to raise awareness of ocean acidification

Published 18 August 2022 Web sites and blogs Closed

The Divers Alert Network (DAN) Sustainable EV Tour 2022 will arrive in Ireland next week, promoting electric vehicles and sustainability to help combat ocean acidification. The team aim to meet as many people as possible to explore ways in which they can help towards solving the global acidification threat, which damages marine life. 

Their next stop is Ireland, where DAN sustainability reps Alana Alvarez and Manu Bustelo will continue their tour – carbon-neutrally – in a 100% electric Hyundai Kona SUV, visiting Galway, Cork and Dublin. They will be holding events at the Dive Academy in The Aran Islands, Oceanaddicts in Kinsale, Oceans of Discovery Dive Center in Robert’s Cove, Cork and OCEANDIVERS in Bray.  

Sustainable EV Tour to raise awareness of ocean acidification

Electric vehicle infrastructure is crucial to supporting the health of our oceans  

Alana Alvarez and Manuel Bustelo (DAN Europe Ambassadors) alongside the DAN team, are travelling across the country using an electric vehicle (Hyundai), educating people in schools, diving and swimming clubs on making the activity safer, more accessible, and sustainable.

The DAN team is only using IONITY’s high-power charging stations on the UK tour because the chargers exclusively use electricity that is generated from renewable sources of energy.

IONITY enables electric travel for everyone in Europe, helping to decarbonise the transport and mobility sector that is responsible for a quarter of all greenhouse gas emissions in the EU. Decarbonisation needs electrification and electrification needs infrastructure. That’s why IONITY is building a pan-European high-power charging network which is open to electric vehicles of all brands.

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Environmental response and pH tolerance of induced CO2 in Ulva rigida C. Agardh, 1823 (Chlorophyta) under controlled conditions

Published 17 August 2022 Science Closed
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The increase in integrated multitrophic aquaculture (IMTA), where seaweed (particularly Ulva rigida C. Agardh, 1823) is used as a feedstock and a wastewater scrubber in South African IMTA systems, has necessitated research into seaweed growth rates, which has subsequently increased production technologies. Seaweed growth can be increased by controlling the culture media. One of the means to control growth rate is through CO2 gas addition to culture media via aeration. This has the potential added benefit of using waste CO2 production from an alternative source to decrease overall carbon dioxide emissions. The consequence of elevated CO2 concentration on the pH of culture medium and the equivalent functional reactions in the seaweed were examined using U. rigida in flow-through systems. Toxicity investigation of Hydrogen ion concentrations were carried out on U. rigida to examine their anatomy cum functional differences arising due to CO2 exerted stress. Elevated CO2 levels and the accompanying decrease in culture media pH (4.71 – 6.67) lead to a significant decrease in biomass with varied sporulation activities. In addition, U. rigida in flow-through systems showed a gradual degeneration in specific growth rate, from day 7, at varying rates until the end of the experiment in the following sequence pH 7.20 > 8.20 > 7.50 > 7.80. The treatment set at pH 7.20 yielded the greatest specific biomass and the greatest produce. The cultured input stocking rate of 5 g.l-1 of seawater proved to be suitable for cultivation. The pH toxicity reaction was significant in predicting the suitability of seaweed cultured under CO2 induced concentrations.

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Net effect of environmental fluctuations in multiple global-change drivers across the tree of life

Published 17 August 2022 Science Closed
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Significance

Recent advances in ecology show evidence that multiple environmental drivers interact and that their impact on community and ecosystem functioning cannot be predicted from single-driver studies. However, ecologists still largely disregard the role that fluctuations in these drivers (i.e., changes above/below mean trends) play in modulating the magnitude and direction of global-change impacts. Through a 30-year quantitative review, we show that contrary to the established paradigm, additive effects are more frequent when environmental fluctuations are considered in multiple-driver (i.e., acidification, hyperpoxia and hypoxia, light, resource supply, or temperature) scenarios, although such effects are strongly dependent on trophic strategy and phylogeny. Our findings stress the need to consider environmental variability in ecological studies and conservation plans to better predict the impacts of global climate change.

Abstract

Jensen’s inequality predicts that the response of any given system to average constant conditions is different from its average response to varying ones. Environmental fluctuations in abiotic conditions are pervasive on Earth; yet until recently, most ecological research has addressed the effects of multiple environmental drivers by assuming constant conditions. One could thus expect to find significant deviations in the magnitude of their effects on ecosystems when environmental fluctuations are considered. Drawing on experimental studies published during the last 30 years reporting more than 950 response ratios (n = 5,700), we present a comprehensive analysis of the role that environmental fluctuations play across the tree of life. In contrast to the predominance of interactive effects of global-change drivers reported in the literature, our results show that their cumulative effects were additive (58%), synergistic (26%), and antagonistic (16%) when environmental fluctuations were present. However, the dominant type of interaction varied by trophic level (autotrophs: interactive; heterotrophs: additive) and phylogenetic group (additive in Animalia; additive and positive antagonism in Chromista; negative antagonism and synergism in Plantae). In addition, we identify the need to tackle how complex communities respond to fluctuating environments, widening the phylogenetic and biogeographic ranges considered, and to consider other drivers beyond warming and acidification as well as longer timescales. Environmental fluctuations must be taken into account in experimental and modeling studies as well as conservation plans to better predict the nature, magnitude, and direction of the impacts of global change on organisms and ecosystems.

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Physicochemical control of Caribbean coral calcification linked to host and symbiont responses to varying pCO2 and temperature

Published 17 August 2022 Science Closed
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It is thought that the active physiological regulation of the chemistry of a parent fluid is an important process in the biomineralization of scleractinian corals. Biological regulation of calcification fluid pH (pHCF) and other carbonate chemistry parameters ([CO32−]CF, DICCF, and ΩCF) may be challenged by CO2 driven acidification and temperature. Here, we examine the combined influence of changing temperature and CO2 on calcifying fluid regulation in four common Caribbean coral species—Porites astreoides, Pseudodiploria strigosa, Undaria tenuifolia, and Siderastrea siderea. We utilize skeletal boron geochemistry (B/Ca and δ11B) to probe the pHCF, [CO32−]CF, and DICCF regulation in these corals, and δ13C to track changes in the sources of carbon for calcification. Temperature was found to not influence pHCF regulation across all pCO2 treatments in these corals, in contrast to recent studies on Indo-Pacific pocilloporid corals. We find that [DIC]CF is significantly lower at higher temperatures in all the corals, and that the higher temperature was associated with depletion of host energy reserves, suggesting [DIC]CF reductions may result from reduced input of respired CO2 to the DIC pool for calcification. In addition, δ13C data suggest that under high temperature and CO2 conditions, algal symbiont photosynthesis continues to influence the calcification pool and is associated with low [DIC]CF in P. strigosa and P. astreoides. In P. astreoides this effect is also associated with an increase in chlorophyll a concentration in coral tissues at higher temperatures. These observations collectively support the assertion that physicochemical control over coral calcifying fluid chemistry is coupled to host and symbiont physiological responses to environmental change, and reveals interspecific differences in the extent and nature of this coupling.

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New exploration vessel starts collecting Arctic Ocean data with FerryBox onboard

Published 17 August 2022 Web sites and blogs Closed

Seawater sensor and measuring system manufacturer -4H-JENA engineering’s FerryBox, a multi-parameter water measurement system, is now being used to evaluate the role of global warming and glacial meltwater on the rising level of oxygen in the oceans aboard Ponant’s Le Commandant Charcot, one of the world’s few luxury icebreakers, a hybrid-electric vessel powered by liquified natural gas.

A unique concept with minimal environmental impact due to her green energy and propulsion systems, Le Commandant Charcot provides a luxurious environment for guests seeking adventure away from the traditional cruise destinations in addition to providing extensive facilities for scientific projects with two research laboratories, one of which is open to the sea.

Bioproductivity and the Concentration Distribution of CO2

Installed this spring by -4H-JENA engineering technicians in Cherbourg, France, measurement parameters for Le Commandant Charcot’s FerryBox include basics such as temperature, salinity and sound velocity, in addition to measurements that determine the concentration of dissolved oxygen and CO2, which provides insight into bioproductivity and the concentration distribution of CO2. The latter is especially important to the study of global warming, ocean acidification and the CO2 absorption function of the oceans.

With her inaugural Arctic voyage starting early in June and a sell-out 2022 season ahead, Le Commandant Charcot’s dual exploration voyage and scientific research approach is paying off. While guests get to reach the geographical North Pole and go kayaking on pristine waters, they can also participate through workshops and seminars hosted by the scientists onboard who are conducting important research, which in addition to projects using FerryBox data includes the study of ocean plastic pollution and analysis of humpback whale behaviour.

“There is relatively little ocean data from the Arctic and Antarctic available, but with FerryBox alongside the laboratory facilities and other scientific sensors and equipment aboard Le Commandant Charcot, we plan to change that,” said Ponant science programme coordinator, Vladislav Sidorenkov-Duprez. “Le Commandant Charcot’s itinerary takes FerryBox further north than the current highest FerryBox installation in Svalbard, allowing us to extend the geographical scope for autonomous water measurements even further using a solution that we can rely on to deliver accurate readings in any conditions.” 

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Technical officer – laboratory & aquaria

Published 17 August 2022 Jobs Closed

Applications close: 24 August 2022

Apply

Description

As our Technical Officer – Laboratory and Aquaria you will join a small, dedicated team and contribute to the daily operations of our state-of-the-art aquaria laboratory ensuring compliance with health, safety and environment protocols and integrity of procedures are maintained.  You will administer laboratory experiments as well as generate high quality data measurements and analysis reports. You will also support multiple research projects with competing deadlines and may also provide occasional field support for various research groups.

Your work will directly support our ecotoxicological research group and you will be the primary contributor for the husbandry of broodstock marine biota. 

At AIMS, the way we work guides our team members’ on their collective journey towards the successful delivery of our AIMS Strategy 2025 targets.

Apply now and join a world leading organisation with attractive working conditions.  In line with our Enterprise Agreement, the successful candidate will be rewarded with:

  • AIMS AOF Level 3 salary ($68,759 to $77,477 per annum) plus 15.4% superannuation
  • Full-time, Permanent opportunity
  • Located in Darwin (NT). Relocation Assistance available
  • 9-day fortnight
  • Flexible Work Arrangements considered (including tele-working where possible)
  • Generous leave provisions

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About you

Underpinning your suitability for this position will be your tertiary qualification in a relevant field (biology, environmental science, or ecotoxicology) and/or equivalent technical experience working in a laboratory environment, including the use of analytical equipment and microscopes. You will also be able to demonstrate your:

  • Sound understanding of biology, chemistry and ecotoxicology and the ability to maintain live biota in a recirculating aquaria system;
  • Ability to work independently and in a team environment and to demonstrate flexibility and effective collaboration to meet project demands and deadlines;
  • Willingness to learn and implement new skills, whilst also recognising continuous improvement opportunities for outputs and performance; and
  • High attention to detail and excellent technical report writing skills. 

Next Step:

Further information about this exciting and challenging opportunity is outlined in the Candidate Information Pack which is available to download below. If, after reviewing the position description, which is included in the Candidate Information Pack, you believe that your qualifications, experience and professional capabilities will enable you to successfully the deliver the position responsibilities, we would be very interested in hearing from you.

Below you will also find a link to our Recruitment Application Guide which details the necessity to submit your statements addressing your suitability against the selection criteria within the scope of the position description, which are detailed in the Candidate Information Pack.

Submitting your Application:

Please ensure that you have your completed documents (selection criteria responses, resume and cover letter) ready to attach to your online application form via our e-recruitment system which can be accessed via the “apply now” button below.

Shortlisted applicants may be asked to complete a personal outlook analysis questionnaire using the Birkman Method.

Position enquiries are to be directed to Joost Van Dam at j.vandam@aims.gov.au

Applications close: WEDNESDAY, 24 AUGUST 2022 (midnight, AEST).

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Elevated CO2 does not alter behavioural lateralization in free-swimming juvenile European sea bass (Dicentrarchus labrax) tested in groups

Published 16 August 2022 Science Closed
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We investigated left-right turning preferences of N=260 juvenile European sea bass (Dicentrarchus labrax) reared in either: ambient conditions; ocean acidification (OA) conditions; or reared in ambient conditions but tested in OA water. Groups of 10 individuals were observed alone in a circular tank and individuals’ left and right turning during free-swimming were quantified using trajectory data from video. We show that near future OA levels does not affect the number of turns made, or behavioural lateralization (turning preference), in juvenile D. labrax tested in groups.

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Deep-sea sediments and global change: research frontiers and challenges

Published 16 August 2022 Science Closed
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Present-day oceans are experiencing the effects of global change such as warming and acidification caused by human activities. Deep-sea sediments store a detailed archive of past global changes driven by nature during Earth’s evolution. By exploring today’s and past global change processes, we can reveal the characteristics and laws of global change and provide a basis for predicting future changes. The outstanding research progresses made in recent years were the discovery in the deep-sea of a variety of analogous scenarios that humans, when choosing future greenhouse gas emission trajectories, can reference to for evaluating future changes—their processes and consequences —in the Earth system. Among such scenarios, millennium-scale climate events, represented by the Dansgaard-Oeschger oscillation, and decadal-scale climate events, represented by the El Nino-Southern Oscillation (ENSO) and the North Atlantic Oscillation (NAO), are the closest rapid climate change analogues to today’s global warming. The Earth system is currently at the beginning of a “Hothouse Earth” emission trajectory. If the system passes the “tipping points”, it will follow an irreversible path to a “Hothouse Earth” state; whereas an alternative path may lead to a “Stabilized Earth” state. Analogous scenarios in the deep-sea sedimentary archive can provide societies with valuable information in choosing future emission trajectories. The major challenges for researchers are to fully understand the mechanisms of the key processes of global change. Taking the example of ocean warming and acidification’s influence on diatom and coccolithophore functioning as marine biological pump. The conventional knowledge has suggested that acidification is beneficial to diatom formation; but recent mesocosm experiments have found that global diatom output is significantly reduced. Likewise, the suggestion that acidification leads to calcification crisis in marine life has also been proven wrong, as recent black shale studies of Mesozoic oceanic anoxic events showed that calcium carbonate output from coccolithophores increased significantly during ocean acidification. The above examples demonstrate that conventional knowledges of the key processes of global change are under serious challenge.

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Field application of automated spectrophotometric analyzer for high-resolution in situ monitoring of pH in dynamic estuarine and coastal waters

Published 16 August 2022 Science Closed
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High quality pH measurements are required in estuarine and coastal waters to assess the impacts of anthropogenic atmospheric CO2 emissions on the marine carbonate system, including the resulting decrease in pH. In addition, pH measurements are needed to determine impacts on carbonate chemistry of phytoplankton blooms and their breakdown, following enhanced anthropogenic nutrient inputs. The spectrophotometric pH technique provides high quality pH data in seawater, and is advantageous for long-term deployments as it is not prone to drift and does not require in situ calibration. In this study, a field application of a fully automated submersible spectrophotometric analyzer for high-resolution in situ pH measurements in dynamic estuarine and coastal waters is presented. A Lab-on-Chip (LOC) pH sensor was deployed from a pontoon in the inner Kiel Fjord, southwestern Baltic Sea, for a total period of 6 weeks. We present a time-series of in situ pHT (total pH scale) and ancillary data, with sensor validation using discretely collected samples for pHT and laboratory analysis. The difference between the sensor and laboratory analyses of discrete samples was within ±0.015 pHT unit, with a mean difference of 0.001 (n=65), demonstrating that the LOC sensor can provide stable and accurate pHT measurements over several weeks.

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Ocean acidification impacts sperm swimming performance and pHi in the New Zealand sea urchin Evechinus chloroticus

Published 15 August 2022 Science Closed
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In sea urchins, spermatozoa are stored in the gonads in hypercapnic conditions (pH<7.0). During spawning, sperm are diluted in seawater of pH>8.0, and there is an alkalinization of the sperm’s internal pH (pHi) through the release of CO2 and H+. Previous research has shown that when pHi is above 7.2-7.3, the dynein ATPase flagellar motors are activated, and the sperm become motile. It has been hypothesised that ocean acidification (OA), which decreases the pH of seawater, may have a narcotic effect on sea urchin sperm by impairing the ability to regulate pHi, resulting in decreased motility and swimming speed. Here we use data collected from the same individuals to test the relationship between pHi and sperm motility/performance in the New Zealand sea urchin Evechinus chloroticus (Valenciennes) under near- (2100) and far-future (2150) atmospheric pCO2 conditions (RCP 8.5: pH 7.77, 7.51). Decreasing seawater pH significantly negatively impacted the proportion of motile sperm), and four of the six computer-assisted sperm analysis (CASA) sperm performance measures. In control conditions, sperm had an activated pHi of 7.52. E. chloroticus sperm could not defend pHi. in future OA conditions; there was a stepped decrease in the pHi at pH 7.77, with no significant difference in mean pHi between pH 7.77 and 7.51. Paired measurements in the same males showed a positive relationship between pHi and sperm motility, but with a significant difference in the response between males. Differences in motility and sperm performance in OA conditions may impact fertilization success in a future ocean.

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Role of abiotic factors in enhancing the capacity of mangroves in reducing ocean acidification

Published 15 August 2022 Science Closed
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The present study investigated the effects of rising carbon dioxide levels in nature and the carbon sequestration potential of dominant mangrove species for reducing the toxic effects of ocean acidification. The study was conducted on the east coast of Odisha, in the western Bay of Bengal. To determine the effect of these ambient parameters on the absorption of carbon dioxide by the mangroves, water temperature, salinity, pH levels of seawater along with soil texture and pH, salinity expressed in electrical conductivity, compactness expressed in bulk density, and soil organic carbon were simultaneously monitored. The aboveground biomass and carbon of the selected species were studied for 2 consecutive years at 10 designated stations. The total carbon calculated for the study area varied from 242.50 ± 49.00 to 1321.29 ± 445.52 tons with a mean of 626.68 ± 174.81 tons for Bhitarkanika and Mahanadi mangrove chunks. This is equivalent to 2299.92 ± 641.55 tons of CO2 absorbed from the atmosphere. A total of 27 equations were selected as the best fit models for the study area. The equations between mangrove biomass and carbon along with aquatic and edaphic factors governing the pH of water and soil strongly support the positive influence of mangrove photosynthetic activity in shifting the equilibrium toward alkalinity. This calls for conservation of mangrove ecosystem to minimize the pace of acidification of estuarine water. The results indicate that Excoecariaagallocha and Avicennia marina as are the most capable species for combatting maximum carbon dioxide toxicity from the atmosphere; which will be helpful in REDD + programs and carbon-based payments for ecosystem services (PES).

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Energetics, but not development, is impacted in coral embryos exposed to ocean acidification 

Published 15 August 2022 Science Closed
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In light of the chronic stress and mass mortality reef-building corals face under climate change, it is critical to understand the processes driving reef persistence and replenishment, including coral reproduction and development. Here we quantify gene expression and sensitivity to ocean acidification across a set of developmental stages in the rice coral, Montipora capitata. Embryos and swimming larvae were exposed to pH treatments 7.8 (Ambient), 7.6 (Low) and 7.3 (Xlow) from fertilization to 9 days post-fertilization. Embryo and larval volume, and stage-specific gene expression were compared between treatments to determine the effects of acidified seawater on early development. While there was no measurable size differentiation between pH treatments at the fertilized egg and prawn chip (9 hours post-fertilization) stages, early gastrulae and larvae raised in reduced pH treatments were significantly smaller than those raised in ambient seawater, suggesting an energetic cost to developing under low pH. However, no differentially expressed genes were found until the swimming larval stage. Notably, gene expression patterns of larvae developing at pH 7.8 and pH 7.3 were more similar than those developing at pH 7.6. Larvae from pH 7.6 showed upregulation of genes involved in cell division, regulation of transcription, lipid metabolism, and response to oxidative stress in comparison to the other two treatments. While low pH appears to increase energetic demands and trigger oxidative stress in larvae, the developmental process is robust to this at a molecular level, with the swimming larval stage reached in all pH treatments.

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Observations to underpin policy: examples of ocean and coastal observations in support of the Sendai Framework, the Paris Agreement, and Sustainable Development Goal 14

Published 12 August 2022 Science Closed
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The ocean impacts human well-being and sustainability by influencing weather, climate, the economy, health and safety. Ocean and coastal observations play a critical role in enabling decision-makers to understand ocean and coastal issues and shape effective policies. This chapter explores how ocean and coastal observations relate to the development and achievement of three of the Group on Earth Observation’s engagement priority areas: the Sendai Framework for Disaster Risk Reduction, the Paris Climate Agreement, and the United Nations 2030 Agenda for Sustainable Development. Observing systems and outputs covered in this chapter include tsunami warning, storm surge monitoring and forecasting, monitoring ocean heat content, informing climate adaptation, monitoring of marine pollution and ocean acidification and safety at sea alters for fishers.

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A comparison of mixed logit and latent class models to estimate market segments for seafood faced with ocean acidification

Published 12 August 2022 Science Closed
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This study uses a choice experiment to characterize market segments (consumer preferences heterogeneity) based on three attributes of seafood (mussels) that are affected by ocean acidification: shell appearance, meat color, and nutritional composition. Using a sample of 1,257 individuals from two main cities in Chile, we estimate both the Mixed Logit model and the Latent Class model. We use the individual-specific posterior (ISP) parameters’ distribution to categorize consumers’ heterogeneity based on the signs and intensity (i.e., like or dislike dimension) of these ISPs. We compare the pattern of preferences and whether people are classified within the same preference pattern in both models. In general, we observed that the models identify a different number of segments with various patterns of preferences. Moreover, the models classify the same people into different groups. Since the segmentation is sensitive to the chosen model, we discuss strengths, inconsistencies, biases, and best practices regarding methodological approaches to establishing market segments in choice experiments and future ocean acidification conditions.

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Is ocean acidification really a threat to marine calcifiers? A systematic review and meta-analysis of 980+ studies spanning two decades

Published 12 August 2022 Science Closed
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Ocean acidification is considered detrimental to marine calcifiers, but mounting contradictory evidence suggests a need to revisit this concept. This systematic review and meta-analysis aim to critically re-evaluate the prevailing paradigm of negative effects of ocean acidification on calcifiers. Based on 5153 observations from 985 studies, many calcifiers (e.g., echinoderms, crustaceans, and cephalopods) are found to be tolerant to near-future ocean acidification (pH ≈ 7.8 by the year 2100), but coccolithophores, calcifying algae, and corals appear to be sensitive. Calcifiers are generally more sensitive at the larval stage than adult stage. Over 70% of the observations in growth and calcification are non-negative, implying the acclimation capacity of many calcifiers to ocean acidification. This capacity can be mediated by phenotypic plasticity (e.g., physiological, mineralogical, structural, and molecular adjustments), transgenerational plasticity, increased food availability, or species interactions. The results suggest that the impacts of ocean acidification on calcifiers are less deleterious than initially thought as their adaptability has been underestimated. Therefore, in the forthcoming era of ocean acidification research, it is advocated that studying how marine organisms persist is as important as studying how they perish, and that future hypotheses and experimental designs are not constrained within the paradigm of negative effects.

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Roundtable with California Current ocean acidification network

Published 12 August 2022 Events , Presentations Closed

Description: The California Current Ocean Acidification Network (C-CAN) and Washington Sea Grant will host a webinar to help industry stakeholders and natural resource managers and partners understand the mechanisms of Pseudo-nitzschia australis bloom formation and toxicity during seasonal upwelling and marine heatwave scenarios. Kyla Kelly will be the presenter.

When: Wednesday, August 17, at 1 p.m. (PST)

Link: Zoom

Register in advance here. After registering, you will receive a confirmation email about joining the meeting. Following the presentation, there will be a few short informational announcements for the C-CAN community.

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New edition of the “OA-ICC Highlights”, March – July 2022

Published 11 August 2022 Newsletters and reports Closed

The new edition of the “OA-ICC Highlights”, our newsletter, summarizes the project’s main activities and achievements over the period March – July 2022. This newsletter features a training for early career scientists, OA-ICC activities at the UN Ocean Conference, the upcoming 5th Annual Symposium on the Ocean in a High CO2 World, and two new OA-ICC publications, including a policy brief and protocol on measuring pHT. Previous editions can be viewed here.

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Stylasterid corals build aragonite skeletons in undersaturated water despite low pH at the site of calcification

Published 11 August 2022 Science Closed
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Anthropogenic carbon emissions are causing seawater pH to decline, yet the impact on marine calcifiers is uncertain. Scleractinian corals and coralline algae strongly elevate the pH of their calcifying fluid (CF) to promote calcification. Other organisms adopt less energetically demanding calcification approaches but restrict their habitat. Stylasterid corals occur widely (extending well below the carbonate saturation horizon) and precipitate both aragonite and high-Mg calcite, however, their mode of biocalcification and resilience to ocean acidification are unknown. Here we measure skeletal boron isotopes (δ11B), B/Ca, and U/Ca to provide the first assessment of pH and rate of seawater flushing of stylasterid CF. Remarkably, both aragonitic and high-Mg calcitic stylasterids have low δ11B values implying little modification of internal pH. Collectively, our results suggest stylasterids have low seawater exchange rates into the calcifying space or rely on organic molecule templating to facilitate calcification. Thus, despite occupying similar niches to Scleractinia, Stylasteridae exhibit highly contrasting biocalcification, calling into question their resilience to ocean acidification.

Continue reading ‘Stylasterid corals build aragonite skeletons in undersaturated water despite low pH at the site of calcification’

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