Marine Environmental Modelling Group

Global fleet of undersea robots reveals the phytoplankton hidden beneath the ocean's surface

October 30, 2024 - Phys.org: Phytoplankton—microscopic plant-like organisms—are the foundation of the marine food web, sustaining everything from tiny fish to multi-ton whales while also playing a critical role in removing carbon dioxide from the atmosphere.

Accurately monitoring Earth's phytoplankton is essential, especially when it comes to understanding the effects of global warming or possible carbon-removal initiatives. The ability to track phytoplankton has largely depended on space satellites observing the sea surface. Yet, phytoplankton can grow below the surface where satellites cannot detect them, leaving a...

See full article - Phys.org, Global fleet of undersea robots reveals the phytoplankton hidden beneath the ocean's surface

Neuer Wert für die globale Phytoplankton-Biomasse

October 30, 2024, Focus.online: Die Hälfte war verborgen: Wie viel Phytoplankton lebt in den irdischen Meeren – und wie viel Biomasse produzieren diese einzelligen Meeresalgen? Eine neue, genauere Antwort liefern nun Messdaten von Tauchbojen. Sie enthüllen, dass gut die Hälfte der rund 314 Millionen Tonnen Phytoplankton-Biomasse von den gängigen Satellitenmessungen nicht erfasst wurde. Auch die räumliche und zeitliche Verteilung dieser winzigen, als COCO₂-Senke wichtigen Meeresbewohner ist anders als gedacht, wie Forschende berichten.

Das Phytoplankton bildet die Basis aller marinen Nahrungsnetze, durch ihre Photosynthese sind diese mikroskopisch kleinen Meeresalgen zudem eine wichtige COCO₂-Senke im Klimasystem: Ohne das marine Phytoplankton wäre der COCO₂-Gehalt der Erdatmosphäre noch 200 parts per million (ppm)...

See full article - Focus.online, Neuer Wert für die globale Phytoplankton-Biomasse

Global phytoplankton biomass remeasured

October 29, 2024 - Techzle: Tiny sea algae form the basis of all marine food webs and are an important CO2 sink in the climate system. But how much of this phytoplankton is there in the oceans? So far, this has been determined using satellite measurements of the photosynthetic pigment chlorophyll.

But this only covers the phytoplankton on the surface. Now a good 99,000 additional measurements with floating measuring buoys have enabled a closer look at the phytoplankton at greater depths for the first time. According to these measurements, the total biomass of phytoplankton living in the open ocean corresponds to 314 million tons of carbon. However, around half of them are hidden at depths that are not accessible to satellite measurements...

See full article - Techzle, Global phytoplankton biomass remeasured

Globale Phytoplankton-Biomasse neu gemessen

October 28, 2024 - Bild der Wissenschaft: Winzige Meeresalgen bilden die Basis aller marinen Nahrungsnetze und sind eine wichtige CO2-Senke im Klimasystem. Doch wie viel von diesem Phytoplankton gibt es in den Ozeanen? Bisher wurde dies mittels Satellitenmessungen des Photosynthese-Farbstoffs Chlorophyll ermittelt.

Doch dies erfasst nur das Phytoplankton an der Oberfläche. Jetzt haben gut 99.000 ergänzende Messungen mit schwebenden Messbojen erstmals einen genaueren Blick auf das Phytoplankton in größerer Tiefe ermöglicht. Diesen Messungen zufolge entspricht die Gesamt-Biomasse des im offenen Meer lebenden Phytoplanktons 314 Millionen Tonnen Kohlenstoff. Rund die Hälfte davon verbirgt sich jedoch in Tiefen, die für die Satellitenmessungen nicht zugänglich sind. Auch die..

See full article - Bild der Wissenschaft, Globale Phytoplankton-Biomasse neu gemessen

Robot fleet reveals hidden ocean phytoplankton equal to 250 million elephants

October 28, 2024 - Interesting Engineering: Robot fleet reveals hidden ocean phytoplankton equal to 250 million elephants. A network of 903 BGC-Argo robotic floats collected 99,350 bio-optical profiles, estimating global phytoplankton carbon at 314 teragrams.

See full article - Interesting Engineering, Robot fleet reveals hidden ocean phytoplankton equal to 250 million elephants

They've Got a Plan to Fight Global Warming. It Could Alter the Oceans.

September 23, 2024 - The New York Times: In a quiet patch of forest in Nova Scotia, a company is building a machine designed to help slow global warming by transforming Earth’s rivers and oceans into giant sponges that absorb carbon dioxide from the air.

When switched on later this year, the machine will grind up limestone inside a tall green silo and release the powder into the nearby West River Pictou, creating a chalkiy plume that should...

See full article - The New York Times, They've Got a Plan to Fight Global Warming. It Could Alter the Oceans.

Can ocean alkalinity enhancement reduce atmospheric carbon dioxide?

July 4, 2024 - futurum: We must urgently and dramatically reduce our carbon dioxide (CO₂) emissions. However, even if we completely cut emissions tomorrow, the atmosphere will still hold the majority of the CO₂ emitted over the past century. This will continue to affect the climate, so scientists are exploring how to enhance the natural, but slow, removal of CO₂ from the atmosphere. At Dalhousie University in Canada, oceanographers Professor Katja Fennel, Dr Dariia Atamanchuk and Professor Ruth Musgrave are investigating the effectiveness and implications of ocean alkalinity enhancement, a CO₂ removal technique that mimics the natural process of rock weathering.

The need for innovative solutions to fight climate change has never been more urgent. Reducing carbon dioxide (CO₂) emissions is key to addressing the climate crisis. However, the accumulated CO₂ already in the atmosphere will continue to affect the climate even when we cut our emissions, and natural removal processes are too slow to make a difference in the next 100 years. So, scientists and policymakers are investigating methods to enhance natural processes that reduce atmospheric CO₂ while CO₂ reduction efforts continue.

Carbon dioxide removal (CDR) techniques remove CO₂ from the atmosphere and ‘lock it away’ in carbon reservoirs. The ocean is one such reservoir, acting as an impressive ally in our battle against climate change. With remarkable efficiency, the ocean has already absorbed a substantial portion – between 25% and 40% – of the CO₂ emissions generated by human activities. Scientists are now investigating ways to increase the ocean’s ability to absorb and store CO₂, thereby reducing CO₂ in the atmosphere. At Dalhousie University, oceanographers Professor Katja Fennel, Dr Dariia Atamanchuk and Professor Ruth Musgrave are studying the effectiveness and implications of one form of CDR – ocean alkalinity enhancement.

This article was produced by Futurum Careers, a free online resource and magazine aimed at encouraging 14-19-year-olds worldwide to pursue careers in science, technology, engineering, maths and medicine (STEM), and social sciences, humanities and the arts for people and the economy (SHAPE): www.futurumcareers.com

See full article - futurum, Can ocean alkalinity enhancement reduce atmospheric carbon dioxide?

New Funding Announcement to Accelerate Ocean-Climate Research

June 18, 2024 - Carbon to Sea Initiative: Today the Carbon to Sea Initiative (C2S) and COVE are announcing a Joint Learning Opportunity (HERE).

The opportunity is designed to attract and support scientists conducting research and companies piloting new technology for emerging ocean-based carbon dioxide removal solutions. It brings together philanthropic, private sector, and academic partners to accelerate learning and minimize the logistical and financial hurdles that scientific research programs sometimes face.

Funding will increase research and development (R&D) to advance monitoring, reporting, and verification (MRV) and support the evaluation of ocean alkalinity enhancement (OAE) for ongoing field research trials taking place in Halifax, Nova Scotia, Canada. Today’s announcement builds on the existing collaboration between Planetary and researchers from the Dalhousie University contingent of the Ocean Alk-Align research team led by researcher Dr. Katja Fennel.

Teams will be invited to advance research focused on answering scientific, technical and social questions around the feasibility of ocean alkalinity enhancement during the trial period of August to December. This Joint Learning Opportunity will provide additional resources to new research teams to maximize the opportunity to test, trial and observe the impacts of an alkalinity addition that is already planned, thereby increasing its impact, reach and economic efficiencies to...

See full article - Carbon to Sea Initiative, New Funding Announcement to Accelerate Ocean-Climate Research

As Temperatures Rise, So Does Pressure to Engineer the Ocean

June 6, 2024 - The Walrus: In early 2023, members of the Cornwall Marine Liaison Group gathered for a meeting about marine biodiversity featuring a presentation with the Canadian company Planetary Technologies. Over a video call, staff presented their plan to add magnesium hydroxide to the waters of St. Ives Bay, a picturesque crescent on England’s southwest peninsula, via a wastewater pipe. The company pitched the three-month trial as a safe form of carbon dioxide removal—an “antacid for the sea,” says Sue Sayer, founder and director of the Seal Research Trust, who was at the meeting. For the audience, most of whom were highly attuned to the risks of climate change, the idea seemed like something simple and safe.

Months later, though, concerns had surfaced. At a second meeting, this time with townspeople in nearby Hayle, audience members assailed the company with questions: Why St. Ives Bay? What about wildlife? Shortly after that, protesters gathered on a sloping hillside overlooking the bay, holding signs reading “Planetary can stick it up their waste pipe” and demanding more scientific oversight.

Planetary Technologies, based in Nova Scotia, has said that the proposed levels of magnesium hydroxide in the water would be far below that of a toxic dose for marine life; in 2024, an independent audit of the plan deemed it “very low” risk. Planetary also told the community they were committed to extensive monitoring before and after the trial, which was originally set for 2023 but has yet to receive the go-ahead from the UK’s Environment Agency.

See full article - The Walrus, As Temperatures Rise, So Does Pressure to Engineer the Ocean

Inventive intervention for the climate

February 8, 2024, Climate Story Network - Planetary Technologies caused a stir in August 2023 when they helped researchers from Dalhousie University’s Oceanography Department release a pinkish dye into the outfall at the Tufts Cove Generating Station.

That dye-tracing study was part of a new venture that is betting big on carbon removal. Planetary’s wager is that enhancing the alkalinity of seawater will heal marine ecosystems and boost the ocean’s ability to absorb carbon dioxide (CO₂).

Katja Fennel, one of the Dalhousie experts leading the study, says working with Planetary was a practical move.

“This was a mutually beneficial collaboration between our research team and Planetary, which made sense, given the size of the endeavour,” she says.

Will Burt, Planetary’s Chief Ocean Scientist, admits that the method they're using, Ocean Alkalinity Enhancement (OAE), has an unfortunate name.

See full article - Climate Story Network, Inventive intervention for the climate

Une expérience de géoingénierie sur le point de débuter à Halifax

August 20, 2023, Le Devoir - Aux grands maux, les grands moyens ? Dès le mois de septembre, une entreprise va déverser des dizaines de tonnes d’une roche réduite en poudre — de l’hydroxyde de magnésium — dans le port d’Halifax dans le but de retirer du CO2 de l’atmosphère. Le projet-pilote permettra de vérifier l’efficacité de ce procédé, dont les implications écologiques sont pour l’instant inconnues.

L’expérience simule un processus naturel, celui de l’érosion des roches, qui rend les mers moins acides, et donc aptes à absorber davantage de carbone. Cette « alcalinisation artificielle des océans » fait partie des solutions de géo-ingénierie que certains scientifiques disent incontournables pour freiner le réchauffement climatique, et que d’autres considèrent comme imprudentes.

« À notre connaissance, ce sera la toute première fois qu’une expérience d’alcalinisation artificielle des océans sera réalisée du début à la fin, même si c’est à très petite échelle. C’est un moment très important », dit Peter Chargin, l’un des vice-présidents de Planetary Technologies, l’entreprise qui mènera le projet-pilote en collaboration avec l’Université Dalhousie.

See full article - Le Devoir, Une expérience de géoingénierie sur le point de débuter à Halifax

Canadá ha tomado una decisión peculiar en su lucha contra el cambio climático: teñir un puerto de rosa

August 20, 2023, xataka - Hace unos días un grupo de investigadores de la Universidad de Dalhousie se acercó a la estación de Tufts Cove, una planta de generación eléctrica situada en la costa de Halifax, al este de Canadá, y arrojó a su emisario ni más ni menos que 500 litros de un líquido colorante que se extendió por las aguas de la bahía hasta cubrir de rosa un área de 500 metros de diámetro. Igual que si de un estrafalario vertido de chapapote fucsia se tratara, la mancha se prolongó a lo largo del litoral, dibujó más de una mueca de asombro a su paso y, a poco a poco, se esfumó.

No fue una performance relacionada con Barbie.

Ni una gamberrada o despiste de los estudiantes de la Dalhousie.

El propósito del vertido fue bien distinto: combatir el calentamiento global.

See full article - xataka, Canadá ha tomado una decisión peculiar en su lucha contra el cambio climático: teñir un puerto de rosa

Rzeka cała różowa jak Barbie. Wylali hektolitry chemikaliów w imię ekologii i ochrony klimatu

August 15, 2023, Focus - Co się stało w porcie w Halifax, kanadyjskim mieście w prowincji Nowa Szkocja? Wody u wybrzeża zmieniły kolor na różowy, przypominając nieco krajobraz z filmu „Barbie” – tegorocznego hitu kinowego. Okazuje się, że zjawisko wywołano celowo i to w imieniu nauki.

Mieszkańcy Halifax w Nowej Szkocji na pewno byli zdziwieni, kiedy zobaczyli 10 sierpnia, jak wody przy porcie zmieniły kolor na różowy. Do nietypowej sytuacji doszło w zatoce Bedford, do której spływa niewielka rzeka Sackville. „Dziewczęca” barwa wód nie ma jednak związku z tegorocznym hitem kinowym.

See full article - Focus, Rzeka cała różowa jak Barbie. Wylali hektolitry chemikaliów w imię ekologii i ochrony klimatu

Halifax Researchers Want to Alter the Ocean to Slow Climate Change

August 10, 2023, Saltwire - Some people may have noticed the Halifax Harbour near Nova Scotia Power's Tufts Cove Generating Station was glowing pink under the sun on Thursday morning.

That's because researchers from Dalhousie University added 500 litres of pink dye to the outfall of the power station to observe dispersal patterns before going ahead with a plan to add a base to lower the acidity of seawater.

The dye was only visible for a few hours after it entered the water.

See full article - Saltwire, Halifax Researchers Want to Alter the Ocean to Slow Climate Change

Dyeing the Halifax harbour pink to help fight climate change

August 10, 2023, CBC - Some parts of the Halifax harbour turned a bright shade of pink on Thursday — for science.

Researchers with Dalhousie University added pink fluorescent dye to Nova Scotia Power's Tufts Cove Generating Station in Dartmouth, so the colour can be tracked as it moves through the harbour over the next couple of days.

It's part of an experiment that could one day help the ocean better absorb carbon dioxide.

"This is only a small bit, actually, in a much bigger research endeavour," Katja Fennel, an oceanographer leading the research, told CBC Radio's Maritime Noon on Thursday.

See full article - CBC, Dyeing the Halifax harbour pink to help fight climate change

Halifax Researchers Want to Alter the Ocean to Slow Climate Change

June 15, 2023, Huddle.Today - The task is daunting. It is estimated that, in order to prevent the global temperature from rising more than 1.5 degrees, we will have to remove hundreds of billions of tonnes of carbon from the atmosphere this century.

Much focus over the years has been placed on the importance of trees and their ability to remove carbon. Preserving and planting more forests will help in our fight, but what about the ocean?

Many people don’t know that, for eons, the Earth’s largest body of water has been an important carbon sponge for the planet. According to the Carbon to Sea Initiative, 38 trillion tonnes of carbon is stored in the ocean. Now, academic researchers at Dalhousie University are partnering with Halifax’s booming ocean tech sector to allow the ocean to suck up even more carbon from the atmosphere.

See full article - Huddle, Halifax Researchers Want to Alter the Ocean to Slow Climate Change

Could the sea help save us?

June 14, 2023, DalNews - The United Nations calls the ocean “the lungs of the planet.” It absorbs 25 per cent of all carbon dioxide emissions and sequesters up to four times more carbon dioxide (CO₂) from the atmosphere than terrestrial forests. But what if it could take an even deeper breath? What if we could leverage its natural capacity to sequester CO₂ from the atmosphere?

The answer to this question has the potential to be game changing for humanity’s fight against climate change, and Dalhousie has taken the global lead in pursuing it with nearly $15 million in support from the Carbon to Sea Initiative. Lead principal investigator Dr. Katja Fennel, chair of Dalhousie’s Department of Oceanography, says the Ocean Alk-align research program, which includes researchers in North America, Europe, and Australia, will investigate how a human-induced increase in ocean alkalinity could enhance the ocean’s ability to absorb and hold carbon.

See full article - Dal News, Could the sea help save us?

See related CTV interview

$50+ Million “Carbon to Sea Initiative” Will Accelerate Research into Ocean Alkalinity Enhancement, a Promising Carbon Dioxide Removal Approach to Combat Climate Change

June 7, 2023 - The Carbon to Sea Initiative, a non-profit research and development effort, launched today to accelerate research into ocean alkalinity enhancement (OAE), which is a way to address climate change. OAE could be among the most effective and scalable carbon dioxide removal (CDR) approaches.

Carbon to Sea has raised more than $50 million from philanthropic funders and to date has committed $23 million in grant funding to a network of dozens of researchers focused on OAE. Details about the grant-funded research and engineering projects are available at CarbontoSea.org.

See full article - Carbon to Sea Initiative, $50+ Million “Carbon to Sea Initiative” Will Accelerate Research into Ocean Alkalinity Enhancement, a Promising Carbon Dioxide Removal Approach to Combat Climate Change

See Also - MIT Technology Review, Meta’s former CTO has a new $50 million project: ocean-based carbon removal

2023 - Low-oxygen “dead zone” in the northern Gulf of Mexico predicted to grow to 12,600 km² this summer

June 5, 2023 - Dalhousie University scientists forecast that the size of the hypoxic zone (also known as “dead zone”) in the northern Gulf of Mexico will reach 9,200 km² by the end of July, when an annually recurring monitoring cruise typically maps location and extent of the hypoxic zone, and will grow to a maximum extent of 12,600 km² by the end of August. This maximum is more than twice size of Prince Edward Island and smaller by 10% than the 36-year average Gulf hypoxic zone of 13,900 km². The Dalhousie forecast is part of the annual ensemble dead-zone forecast by the National Oceanic and Atmospheric Administration (NOAA) and the United States Geological Survey (USGS). The NOAA and USGS forecast, which is the average of an ensemble of six statistical models including the Dalhousie model, is similar to the Dalhousie forecast.

The hypoxic zone in the northern Gulf of Mexico forms every summer and is the largest in North American coastal waters. Freshwater and plant nutrients—mostly from unused agricultural fertilizer, and urban and industrial wastewater—travel to the Gulf via the Mississippi River. These nutrients stimulate a sequence of biological transformations in coastal waters that significantly decrease oxygen levels near the bottom resulting in an environment unable to support most higher marine life forms.

All forecasts of the hypoxic zone in the northern Gulf of Mexico are based on an estimate of spring nutrient discharge from the Mississippi, determined by the USGS in the first week of June. The forecast model developed by Dalhousie scientists Arnaud Laurent and Katja Fennel is unique in its ability to provide a temporally and spatially explicit forecast, in other words, the hypoxic zone’s location, size, and evolution is predicted throughout the summer season. This is the 6th year that a forecast with this level of detail has been produced (see 2018 forecast here, 2019 forecast here, 2020 forecast here, 2021 forecast here, and the 2022 forecast here).

Many other coastal regions around the globe are experiencing declines in oxygen, leaving marine animals increasingly gasping for breath. In the Canadian Maritimes, the Gulf of St. Lawrence and the Scotian Shelf are suffering from low-oxygen in near-bottom waters, squeezing the habitat of several commercially important and endangered fish species. This trend has been ongoing for several decades, as man-made inputs of nutrients and global warming conspire to depress oxygen levels in coastal ocean waters.

Additional Information

Figure 1: Predicted probability of hypoxic conditions in the northern Gulf of Mexico for July 29, 2023. The black line delimits the most probable region of hypoxic conditions. Figure 2: Predicted temporal evolution of the hypoxic zone in 2022 shown by the black line. Grey shading indicates the 95% confidence interval, a measure of forecast uncertainty. The red dot marks July 29, 2023.

Referenced in - The New York Times, Tens of Thousands of Dead Fish Wash Ashore on Gulf Coast in Texas (subscription required)