Recurring marine heat waves combined with acidification threaten productivity in regions important for fisheries.
Heat waves are associated with sweltering streets and scorched soil. But as likely as humans and cattle, the victims can be corals or fish. Abnormally hot periods also occur in the ocean.
When marine heat waves co-occur with strong acidification and low biological productivity, living conditions in the water deteriorate even further.
“Over the past two decades, the frequency and intensity of these compound events have increased dramatically in the Tropical and South Atlantic,” says Regina Rodrigues, associate professor at the Federal University of Santa Catarina, Brazil.
Rodrigues was recently in Bergen to present her work at the fifth International Symposium on Effects of Climate Change on the World’s Oceans.
Since 2014 compound events of marine heat waves, high acidification and little chlorophyll have occurred practically every year in several biologically important regions in the Tropical and South Atlantic. Regina Rodrigues expresses her worry that the recurring events make it harder for life in the ocean to cope.
“This puts in check the capability of the marine ecosystems to recover from these compound extremes,” she says.
A need for monitoring below the surface
Jerry Tjiputra, researcher at NORCE and the Bjerknes Centre for Climate Research, calls for a long-term monitoring system in key vulnerable regions such as the Southern Ocean and the Tropical and North Atlantic.
Tjiputra has used Earth system models to estimate when anthropogenic signals in the global ocean may be detectable under different climate change scenarios.
While changes in surface water are more easily recognized, his work indicates the need for a closer look at greater depths.
“Changes in temperature, salinity, oxygen and pH can occur earlier in the interior ocean than on the surface”, he says. “Below the surface, where most marine organisms live, anthropogenic signals may already have manifested and are potentially predictable.”
Local action to address global targets
“Local actions can mitigate the negative extremes once we have a good monitoring and prediction system,” says Regina Rodrigues.
In the South Atlantic the Agulhas Leakage or Benguela Current region off the coast of Africa has suffered specifically from compound events.
Lynne Shannon, a research professor from the University of Cape Town, has used the South African marine system as a case study to identify local science-policy actions that would address globally relevant targets.
“Interlinking climate and biodiversity targets remains a challenge,” she says.
An array of South African research activities as well as policy and management measures, strive to address both the climate and biodiversity crises. The activities also address outcomes aimed for in the UN Ocean Decade, namely oceans and coasts that are clean, healthy and resilient, predicted, safe, sustainably harvested and productive, transparent and resilient.
Shannon notes that most of the activities have a strong societal component.
“The challenge worldwide will be to ensure that each of our well formulated research, policy and management activities are actually put into action in our governance system”, she says.
Ecological models such as Ecopath with Ecosim are increasingly used to investigate the effect of various stressors on ecosystems. A recent review of studies using such models found that more work is needed to address the compound effects of all relevant stressors.
Among the 166 studies considered, 60 considered stressors of climate change, 22 considered introductions of new species, 21 considered habitat loss and 20 eutrophication. Only 20 of the 166 studies investigated at least three stressors simultaneously, most focusing on a single stressor.
The authors call for the filling of gaps in approaches to harness to full power of EwE such as deriving functional responses to stressors, including human dimensions of change beyond fishing, and using systematic computational simulations to assess uncertainty.
A. Stock, C.C. Murray, E.J. Gregr, J. Steenbeek, E. Woodburn, F. Micheli, V. Christensen, K.M.A. Chan (2023): Exploring multiple stressor effects with Ecopath, Ecosim, and Ecospace: Research designs, modeling techniques, and future directions, Science of The Total Environment, Volume 869, https://doi.org/10.1016/j.scitotenv.2023.161719.
“There are very obvious shifts and variations in marine ecosystems, partly driven by climatic changes, but also by human pressures like fisheries,” says Noel Keenlyside, professor at the University of Bergen and the Bjerknes Centre for Climate Research.
Keenlyside is the coordinator of the project TRIATLAS, aimed to develop climate-based ecosystem predictions for the Tropical and South Atlantic Ocean.
“It’s a big challenge to understand how environmental changes will influence marine ecosystems. We’re dealing with a problem that extends across disciplinary boundaries and also towards societal aspects,” he continues.
The project team is highly international, consisting of researchers from more than thirty institutes in Europe, South America and Africa.
“Most of the societal challenges and the scientific challenges we are facing to support society, are above the scale of the nation. We need to work as a community across nations to tackle this,” says Roland Séférian from Centre National de Recherches Météorologiques, in Toulouse.
Both physical oceanographers and marine biologists are involved, as well as researchers working to enable policy makers to tackle socioeconomic challenges. A major goal is to contribute to the sustainable development of the region.
“You can’t manage fish, right? Fish are not black cattle that you can put in a pasture and there’s a fence around it. We have to manage people’s behavior in our marine systems,” says Louise Gammage, a specialist in marine sustainability from the University of Cape Town.
Whether you are planning an article for TRIATLAS, or you already have a first draft, this is for you!
Sign up for the TRIATLAS – CANEMS Writing with Results workshop before 15th March.
Many PhD students and early career researchers struggle with writing efficiently and are unconfident about their writing skills. This is why TRIATLAS – CANEMS is collaborating with Mathew Stiller-Reeve to put on an extended workshop that will follow your real-life, academic writing process.
The “Writing with Results” workshop will take place as online sessions spread over 8 weeks (with two breaks), instead of consecutive days over one or two weeks. In this way, you will get support for the entire writing process for one of your TRIATLAS-related articles. By the end of the workshop, you will hopefully have a research article ready for submission.
The Cross-Atlantic Network of Excellence in Marine Science (CANEMS) is a program initiated by TRIATLAS Project to support capacity strengthening across the Atlantic. CANEMS has an open call for mini-grants to help consolidate research and training efforts in the final phase of the project.
Who can apply?
All Early Career Researchers (ERCs)* working under the TRIATLAS Project, performing any of the project tasks, therefore, contributing to its deliverables and milestones are welcome to apply.
*All masters degree and PhD students, and post-doctoral fellows regardless of their age are considered ERCs in the TRIATLAS Project.
What can be supported?
Research exchange between TRIATLAS partner institutes
Participation in relevant summer schools
Other novel ideas
How much funding is available?
Funding for mini-grants is limited, and individual grants are not expected to exceed 5000 Euro. EU’s financial eligibility rules apply!
How to apply?
Applications should be brief and not exceed the word limits given in the application form:
A description of the purpose of the grant. Motivation for applying.
Explain how it will contribute to the goals of the CANEMS and to the TRIATLAS objectives in general. Please be as specific as possible, i.e., mention relevance to tasks, milestones, deliverables, where applicable.
CV (one-page, in PDF, must have “post-secondary education”, “scientific background and interests”, “work experience and skills” sections.)
Timeline (activity must be completed by November 30, 2023)
Budget (subject to approval)
The application deadline is March 15th. Applications after this deadline may be considered if funding is available.
How will applications be evaluated?
CANEMS and TRIATLAS management will review all applications and rank them according to the relevance to CANEMS goals, TRIATLAS objectives, and feasibility.
All applicants will receive an acknowledgement email once they submit their application, however, only those who are granted CANEMS funds will be contacted again.
Feel free to send an email to firstname.lastname@example.org with the subject line “CANEMS mini-grants” should you have any questions.
A network for young climate scientists brings together disciplines and nationalities from all around the Atlantic Ocean.
“The new researchers can understand not only what happens in their own backyard, but also what happens on the other side of the Atlantic,” says José Muelbert.
Muelbert, a professor at Universidade Federal do Rio Grande, is one of the researchers in TRIATLAS, an international and multi-disciplinary research project on climate and ecosystem predictions in the Tropical and South Atlantic.
He is also the leader of The Cross-Atlantic Network of Excellence in Marine Science (CANEMS), a network for young researchers, organized through TRIATLAS.
The CANEMS network combines summer schools, student exchange programs, sea-going training and academic teaching in a highly interdisciplinary context.
José Muelbert emphasizes the importance of bringing together young researchers from West Africa, South America and Europe so they can understand the physical processes that occur in different regions. These processes interact to produce fish stocks that are relevant for the Atlantic community as a whole.
A school of fish and physics
Oceanographers Mareike Körner from GEOMAR and Marie-Lou Bachèlery from the Bjerknes Centre for Climate Research and the University of Bergen met at a CANEMS summer school near Recife in Brazil in October 2022. The summer school was organized by the TRIATLAS and TAPIOCA projects together with Universidade Federal de Pernambuco.
Young researchers with backgrounds from physical or biological oceanography, some working with observations and others with models, spent a week together learning about each others’ fields.
“So much of the world is covered by water, and a lot of people and countries rely on the ocean ecosystem as a food source. Just studying the ocean from a purely physical point of view would not make sense”, says Mareike Körner, who uses observations from the upwelling system off the coast of Angola in her research.
Marie Lou Bachèlery agrees. Like Körner she is a physical oceanographer, though a modeler.
“We have this idea sometimes that everything is going to be linear from physics to fish”, she says. “It is actually much more complex than that. This is something that I got when I started having contact with biologists.”
The summer school made them realize they had common interests.
“We might continue to work together”, Marie-Lou Bachèlery says.
Learn more about the summer school in the video below.
A hybrid event at the European Parliament Thursday 2nd March will look into findings of the iAtlantic project, concerned with understanding the factors that control the distribution, stability and vulnerability of ecosystems in the Atlantic Ocean.
TRIATLAS coordinator Prof. Noel Keenlyside will participate in a panel discussion.
An international effort enhances knowledge of currents and ecosystems in a data-sparse region of the global ocean.
To extend a network of observations in the South Atlantic Ocean, two new scientific, full-depth, instrumented moorings have been deployed off the eastern coast of South America. These tall moorings will measure variations in the Atlantic circulation – a system of ocean currents affecting life in the ocean as well as the weather and economy of coastal nations.
The Atlantic Meridional Overturning Circulation (AMOC), consisting of an upper-ocean northward flow compensated by a southward deep-ocean flow, is a main engine of the Earth’s climate system. This upper AMOC cell is connected to deep-water formation and sinking in the subpolar North Atlantic and upwelling in the Southern Ocean. Beneath the upper cell is a weaker abyssal cell, sourced by the sinking of dense water near Antarctica.
With global warming the system is thought to become weaker. As well as such long-term circulation changes, natural variations on shorter timescales occur. These may be due to reductions of sinking water in the north, but also to changes in the water mass exchange in the south.
“The South Atlantic is particularly important,” says Peter Brandt, professor at the GEOMAR Helmholtz Centre for Ocean Research.
“Changes in the AMOC that result from water mass exchanges between the Atlantic and the Indian and Pacific oceans, can best be detected in the south, and then compared to changes originating in the well-observed North Atlantic,” he explains.
“The South Atlantic is the only ocean basin with a net equatorward heat transport, and where freshwater transports may be key to AMOC stability. It is also the basin where the upper and abyssal overturning cells of the AMOC are both important,” adds María Paz Chidichimo, leader of the research involving the new tall moorings.
Chidichimo is a researcher at the Argentine Scientific Research Council (CONICET), the Hydrographic Service and the French-Argentine Institute for Climate Studies, CNRS/IRD/CONICET UBA UMI 3351 IFAECI, in Buenos Aires.
The new moorings contribute to an existing measurement array along 34.5 degrees south on both sides of the Atlantic Ocean, termed South Atlantic MOC Basin-wide array (SAMBA). The SAMBA array is a component of the multi-national South Atlantic Meridional Overturning Circulation (SAMOC) Initiative, established in 2007 to measure ocean currents and the transport of heat and salt at key locations in the South Atlantic Ocean.
While existing measurements in the southwestern Atlantic are to a large extent performed using echosounders situated on the sea floor, the new moorings will directly measure seawater properties throughout the water column, from the seafloor up to the surface.
Data for the future
“We are proud to contribute to the long-term efforts to maintain and develop the global observing system,” says Peter Brandt.
He emphasizes that the goal is to measure changes in climate through the coming decades, not only within the timeframes of a single research project.
The moorings were deployed by the EU Horizon 2020 sister projects iAtlantic and TRIATLAS, contributing to the fulfillment of the Belem Statement – a joint declaration on Atlantic research between the European Union, Brazil and South Africa – as well as bilateral agreements between the European Union and Argentina, and with other countries.
Influencing climate, weather and ecosystems
The South Atlantic has received far less observational effort than the North Atlantic during recent decades. The lack of sufficient physical oceanography information near the coasts also limits our understanding of marine ecosystems.
María Paz Chidichimo emphasizes the need to enhance oxygen measurements in tandem with physical measurements to better track water masses and evaluate changes relevant to ecosystems in the South Atlantic.
“Continuous full-depth observations are critical to detect and understand combined variations of ocean currents and physical and biogeochemical water mass properties associated with climate change,” she says.
She hopes the new moorings will shed light on the impacts of western boundary currents and the AMOC on regional weather, climate, ocean extreme events and sea level, as well as on the content of heat, salt and oxygen in the water. These properties influence ecosystems, marine resources and ocean health.
“The new observations will improve the capacity to model some of the changes and improve predictive tools in a region where full-depth continuous in situ observations are sparse,” says María Paz Chidichimo.
iAtlantic is a multidisciplinary research program seeking to assess the health of deep-sea and open-ocean ecosystems across the Atlantic Ocean.
The project is financed by the EU Horizon 2020.
Coordinator: Prof. Murray Roberts, The University of Edinburgh
Deputy coordinator: Colin Devey, GEOMAR
The South Atlantic Meridional Overturning Circulation (SAMOC) Initiative is a group dedicated to advancing our understanding of the role of the South Atlantic Ocean in the meridional overturning system and the establishment of an observing system to capture key components of the circulation.
The South Atlantic MOC Basin-wide array (SAMBA) array at 34.5°S in the Southwest South Atlantic is funded by: SAM project (NOAA-AOML/NOAA-GOMO, USA); Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) and Servicio de Hidrografía Naval (SHN) (Argentina); SAMBAR project (Oceanographic Institute of the University of São Paulo, Brazil); GEOMAR Helmholtz Centre for Ocean Research Kiel (Germany), iAtlantic and TRIATLAS.