Archive for March, 2019

The Ocean Foundation to host ocean acidification training for the Senate of Mexico

Date: March 29, 2019

TOF Contact:
Mark J. Spalding, President. mspalding(at)oceanfdn.org
Jason Donofrio, External Relations Officer; jdonofrio(at)oceanfdn.org

Announcing: Ocean Acidification Training for the Senate of Mexico; Commission on the Environment, Natural Resources & Climate Change

Senate of the Republic; Mexico City, Mexico  –  On March 29th, The Ocean Foundation (TOF) will conduct a training workshop for the elected leaders of the Mexican Senate’s Commission on the Environment, Natural Resources and Climate Change to help understand the devastating effects ocean acidification (OA) is creating, and the action steps they can take to help address it.  The Commission is chaired by Senator Eduardo Murat Hinojosa and its members are comprised of Senators from a broad swath of political constituencies.

Continue reading ‘The Ocean Foundation to host ocean acidification training for the Senate of Mexico’

Ocean acidification could impact Atlantic cod populations more severely than previously thought

Decreasing pH values in seawater harm cod larvae more than previously thought. Photo Credit: Catriona Clemmesen/GEOMAR, licensed under CC BY 4.0.

A 2016 study determined that, at the ocean acidification levels expected by the end of the century if we do nothing to draw down CO2 emissions, twice as many cod larvae will die within their first 25 days, causing the number of cod who reach maturity and reproduce to drop by 8 and 24 percent for the Western Baltic and Barents Sea populations, respectively.

Scientists hoped that those cod who managed to reach maturity might be helping the species adapt to the conditions brought on by global climate change. But new research appears to have dashed those hopes.

The new study, which was published in the journal Global Change Biology last month, found that surviving cod larvae suffer significant organ damage and developmental delays that could cause problems throughout their lifetimes.

Continue reading ‘Ocean acidification could impact Atlantic cod populations more severely than previously thought’

Bonamici, Kilmer, Herrera Beutler, Young introduce bipartisan bill to fight ocean acidification

Washington, DC – Today Representatives Suzanne Bonamici (OR-1), Derek Kilmer (WA-6), Jaime Herrera Beutler (WA-3), and Don Young (AK-AL), reintroduced bipartisan legislation to help fight ocean acidification. The bill, entitled the Ocean Acidification Innovation Act, would allow federal agencies to use existing funds to conduct prize competitions to increase the ability to research, monitor, and manage ocean acidification and its impacts.

“Coastal communities in Oregon and across the country are already facing the devastating effects of ocean acidification, and we must strengthen our approach,” said Rep. Bonamici. “The Ocean Acidification Innovation Act’s prize competition will encourage collaboration and spur innovative strategies to mitigate and adapt to ocean acidification. This will help the communities, environments, and industries that rely on healthy oceans and are facing the harsh realities of rising carbon emissions.”

Continue reading ‘Bonamici, Kilmer, Herrera Beutler, Young introduce bipartisan bill to fight ocean acidification’

Citizen science observations reveal rapid, multi-decadal ecosystem changes in eastern Long Island Sound

Highlights

• Citizen-science observations revealed rapid warming, acidification, and dissolved oxygen loss over the past 40 years in eastern Long Island Sound.
• Otter trawl catches showed significant decreases in overall species diversity and richness.
• Cold-water adapted species (American lobster, winter flounder) decreased, but warm-water adapted species (spider crabs) increased since 1997.

Abstract

Long-term environmental records are among the most valuable assets for understanding the trajectory and consequences of climate change. Here we report on a newly recovered time-series from Project Oceanology, a non-profit ocean science organization serving New England schools (USA) since 1972. As part of its educational mission, Project Oceanology has routinely and consistently recorded water temperature, pH, and oxygen as well as invertebrate and fish abundance in nearshore waters of the Thames River estuary in eastern Long Island Sound (LIS). We digitized these long-term records to test for decadal trends in abiotic and biotic variables including shifts in species abundance, richness, and diversity. Consistent with previous studies, the data revealed an above-average warming rate of eastern LIS waters over the past four decades (+0.45 °C decade−1), a non-linear acidification trend twice the global average (−0.04 pH units decade−1), and a notable decline in whole water-column dissolved oxygenconcentrations (−0.29 mg L−1 decade−1). Trawl catches between 1997 and 2016 suggested a significant decrease in overall species diversity and richness, declines in cold-water adapted species such as American lobster (Homarus americanus), rock crab (Cancer irroratus), and winter flounder (Pseudopleuronectes americanus), but concurrent increases in the warm-water decapod Libinia emarginata (spider crab). Our study confirmed that Long Island Sound is a rapidly changing urban estuary, while demonstrating the value of long-term observations made by citizen-scientists, educators, and other stakeholders.

Continue reading ‘Citizen science observations reveal rapid, multi-decadal ecosystem changes in eastern Long Island Sound’

Calibration of the pH-δ11B and temperature-Mg/Li proxies in the long-lived high-latitude crustose coralline red alga Clathromorphum compactum via controlled laboratory experiments

A solid understanding of global oceanic change throughout Holocene time is needed to contextualize and interpret recent observations of rapid warming (Moore, 2016), ocean acidification (Popova et al., 2014Qi et al., 2017), increasing meltwater input (Halfar et al., 2013Notz and Stroeve, 2016) and circulation changes (Liu et al., 2017Rahmstorf et al., 2015Yang et al., 2016) in the Arctic and subarctic Oceans. Precisely reconstructing acidification and temperature variations throughout the Holocene will provide a vital context for interpreting current environmental changes and future climate projections in the region. However, existing paleoenvironmental reconstructions are sparse and uncertain, largely owing to limited availability of high fidelity paleoceanographic archives, such as marine carbonates, in high latitude waters. Coralline algae of the genus Clathromorphum have emerged as key candidates for reconstructing high-latitude environmental variability at annual to sub-annual resolution. Here, we present the first empirical calibrations of boron isotope-pH and Mg/Li-temperature relationships within the long-lived, crustose coralline red alga Clathromorphum compactum. Calibration experiments were performed in triplicate, growing wild-collected specimens for four months at three controlled temperatures (6.4 – 12.4 oC) and four pCO2 conditions (352 – 3230 ppm), to test the effects of these environmental parameters on the isotopic and elemental composition of the algal skeleton.We find that boron isotopes within the skeleton of C. compactum (δ11Bcc) are well correlated with δ11B of seawater borate (δ11Βborate), defining the following equation: δ11Βcc (2σ) = 1.46 (0.06) δ11Βborate + 6.91 (0.72). This equation can be used to reconstruct δ11Βborate of the coralline alga’s ambient seawater, from which past seawater pH can be calculated. We also identified a strong correlation between skeletal Mg/Li ratio and seawater temperature, defined by the equation: Mg/Li (2σ) = 0.17 (0.02) temperature (oC) + 1.02 (0.16). Therefore, despite the strong biological control that this species appears to exert on calcification site pH (elevated 1.0-1.6 pH units above seawater pH, inferred from δ11Bcc > δ11Βborate), and the apparent relationship between skeletal extension rate and skeletal Li/Ca and Mg/Ca, the δ11Bcc and Mg/Li ratios of the coralline alga’s skeleton strongly and significantly respond to ambient seawater pH and temperature, respectively. These results support the use of δ11B and Mg/Li within C. compactum for pH and temperature reconstructions of northern high-latitude oceans.

Continue reading ‘Calibration of the pH-δ11B and temperature-Mg/Li proxies in the long-lived high-latitude crustose coralline red alga Clathromorphum compactum via controlled laboratory experiments’

Drivers of pH variability in coastal ecosystems

A synthesis of long-term changes in pH of coastal ecosystems shows that, in contrast to the uniform trends of open-ocean acidification (-0.0004 to -0.0026 pH units yr-1) driven by increased atmospheric CO2, coastal ecosystems display a much broader range of trends (-0.023 to 0.023 pH units yr-1) and are as likely to show long-term increase as decline in pH. The majority of the 83 investigated coastal ecosystems displayed non-linear trends, with seasonal and interannual variations exceeding 1 pH unit for some sites. The high pH variability of coastal ecosystems is primarily driven by inputs from land. These include freshwater inputs that typically dilute the alkalinity of seawater thereby resulting in reduced buffering, nutrients enhancing productivity and pH, as well as organic matter supporting excess respiration driving acidification. For some coastal ecosystems, upwelling of nutrient-rich and corrosive water may also contribute to variability in pH. Metabolic control of pH was the main factor governing variability for the majority of coastal sites, displaying larger variations in coastal ecosystems with low alkalinity buffering. pH variability was particularly pronounced in coastal ecosystems with strong decoupling of production and respiration processes, seasonally or through stratification. Our analysis demonstrate that coastal pH can be managed by controlling inputs of nutrients, organic matter, and alkalinity. In well-mixed coastal waters, increasing productivity can improve resistance to ocean acidification, whereas increasing productivity enhances acidification in bottom waters of stratified coastal ecosystems. Environmental management should consider the balance between the negative consequences of eutrophication versus those of acidification, to maintain biodiversity and ecosystem services of our coastal ecosystems.

Continue reading ‘Drivers of pH variability in coastal ecosystems’

Interaction of short-term copper pollution and ocean acidification in seagrass ecosystems: toxicity, bioconcentration and dietary transfer

Highlights

• Toxicity and bioconcentration of copper in seagrasses were not affected by pH.
• Complex copper-pH interactions were observed in the seagrass photosynthesis.
• Seagrasses can act as a copper source in the food web via direct consumption.

Abstract

We aimed to show how the predicted pH decrease in the ocean would alter the toxicity, bioconcentration and dietary transfer of trace metal copper on seagrass ecosystems, on a short-term basis. Seagrass Zostera noltei was exposed to two pH levels (8.36 and 8.03) and three copper levels (nominal concentrations, <3, 30 and 300 μg Cu L−1) in a factorial design during 21 days, while Gammarus locusta amphipods were continuously fed with the treated seagrass leaves. We found that the toxicity and bioconcentration of copper in seagrasses were not affected by pH, yet complex copper-pH interactions were observed in the seagrass photosynthesis. We demostrated that seagrasses can act as a copper source in the food web via direct consumption by herbivores. Future research need to investigate the interactive effects on a long-term basis, and to include biochemical and molecular endpoints to provide additional insights to the complex phisiological interactions observed.

Continue reading ‘Interaction of short-term copper pollution and ocean acidification in seagrass ecosystems: toxicity, bioconcentration and dietary transfer’

Ocean acidification: dealing with uncharted waters

There are ancient air bubbles trapped in ice that have allowed NASA to observe what Earth’s atmosphere was like in the past 400,000 years. Through research, NASA discovered the carbon dioxide (CO2) levels in the atmosphere are higher than they have ever been. Since the industrial revolution, it is no secret humans have contributed immensely to the significant increase of CO2. In fact, the Earth’s oceans absorb an astonishing amount of CO2 emissions. Today, the Earth’s oceans absorb twenty-two million tons of CO2 every day. To make things more troublesome, researchers are predicting CO2 levels will continue to rise in the coming years, resulting in unprecedented effects to Earth. When the Earth’s ocean absorbs an increase of CO2, there is a corresponding increase in the acidity levels of the ocean’s chemical makeup. The astoundingly high levels of CO2 have resulted in Earth’s oceans becoming thirty percent more acidic than in recorded history. This underappreciated issue is called ocean acidification, and its effects create profound consequences. Ocean acidification is threatening the ocean’s chemical makeup, ecosystems, marine organisms, and biodiversity. “Absent immediate action, ‘irreversible, catastrophic changes to marine ecosystems’ are anticipated to occur[,]” even endangering human life. Although these facts are troubling, humans have the resources and ability to mitigate our ocean’s chemical makeup and change its terrifying future.

Continue reading ‘Ocean acidification: dealing with uncharted waters’

MBARI design used in ocean-acidification experiments around the world

MBARI design used in ocean-acidification experiments around the world

Modeled after similar systems on land, this first-generation FOCE system in MBARI’s test tank used a circular frame to release carbon dioxide-enriched seawater into a central chamber. Credit: MBARI

MBARI scientists and engineers have been developing new methods to study ocean acidification and its effects on marine organisms in their natural habitats for 15 years. Researchers around the world have been adapting MBARI instruments to perform their own experiments in habitats ranging from coral reefs to the Antarctic seafloor. These diverse projects have recently been highlighted in an article in the journal Progress in Oceanography.

Continue reading ‘MBARI design used in ocean-acidification experiments around the world’

Ocean acidification and high irradiance stimulate growth of the Antarctic cryptophyte Geminigera cryophila

Ecophysiological studies on Antarctic cryptophytes to assess whether climatic changes such as ocean acidification and enhanced stratification affect their growth in Antarctic coastal waters in the future are lacking so far. This is the first study that investigated the combined effects of increasing availability of pCO2 (400 and 1000 µatm) and irradiance (20, 200 and 500 μmol photons m−2 s−1) on growth, elemental composition and photophysiology of the Antarctic cryptophyte Geminigera cryophila. Under ambient pCO2, this species was characterized by a pronounced sensitivity to increasing irradiance with complete growth inhibition at the highest light intensity. Interestingly, when grown under high pCO2 this negative light effect vanished and it reached highest rates of growth and particulate organic carbon production at the highest irradiance compared to the other tested experimental conditions. Our results for G. cryophila reveal beneficial effects of ocean acidification in conjunction with enhanced irradiance on growth and photosynthesis. Hence, cryptophytes such as G. cryophila may be potential winners of climate change, potentially thriving better in more stratified and acidic coastal waters and contributing in higher abundance to future phytoplankton assemblages of coastal Antarctic waters.

Continue reading ‘Ocean acidification and high irradiance stimulate growth of the Antarctic cryptophyte Geminigera cryophila’


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Ocean acidification in the IPCC AR5 WG II

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