Category: Ocean Systems

The Eᶜ simulator – A tool for helping us make sustainable investments in Floating Offshore Wind Farms (FLOW)

js1455 Leave a comment

Authors – Justin Olosunde (Project Lead) and Professor Lars Johanning (the Deputy Head of Engineering and Co-Director Centre for Doctoral Training in Offshore Renewable Energy at the University of Exeter)

The Cornwall and Isles of Scilly Local Enterprise Partnership (CIOS LEP) have identified the Cornwall and Scillies region as the birthplace of commercial wind generation in the UK. It has one of the best wind climates in Europe and has committed to the UK Government agenda as one of only two places in the UK singled out by the Government’s Net Zero Strategy for large-scale FLOW deployment. Some 300MW of projects are already moving forward, with a 30–40MW demonstrator expected to be on-site by 2025.

“The LEP has set a target of 3GW of installed capacity, which could support more than 11,000 jobs and generate £900 million of net additional gross value added.”

~ Mark Duddridge, Chair of The Cornwall and Isles of Scilly Local Enterprise Partnership, 2021

Celtic Sea Power is leading the Cornwall Floating Offshore Wind Accelerator, a part European Regional Development Funded project, which will develop tools, knowledge, and data to accelerate the Celtic Sea FLOW opportunity. They hope to lay the significant groundwork to develop a pipeline at both a FLOW project and supply chain level. The University of Exeter, University of Plymouth, and the Offshore Renewable Energy Catapult have partnered to achieve this. Here at the University of Exeter, we are working toward designing, developing, and building a floating offshore wind simulator as a vehicle to help provide research-led expertise to reduce carbon footprints and underpin the FLOW service.

Partnerships created between the University of Exeter and external partners are contributing toward the development of tools, knowledge, and data that accelerate the Celtic Sea FLOW opportunity. These partnerships are laying significant groundwork, with respect to developing a pipeline at both a FLOW project and supply chain level.

A team within the University of Exeter are undertaking research on Floating Offshore Wind via the Cornwall FLOW accelerator, which is a part of The European Regional Development Fund (ERDF) programme. The programme is led by Celtic Sea Power, a wholly owned subsidiary of Cornwall Council. Justin Olosunde, The Impact and Partnership Development Manager for Cornwall FLOW Accelerator and Lars Johanning, the Deputy Head of Engineering and Co-Director Centre for Doctoral Training in Offshore Renewable Energy at the University of Exeter, are part of the Exeter team leading on the design of the tool, to develop a floating offshore wind simulator as a vehicle.

¹ Team photo for the Exeter floating offshore wind simulator team. Left to right: Jessye Boulton, me, Dr Hailun Xie, Dr Barton Chen, Professor Lars Johanning, Dr Mi Tian, Dr Kanchan Joshi and Dr Shuya Zhong.

² Floating offshore wind turbines identified for Hexicon Celtic Sea development site (RenewablesNow

The Eᶜ simulator is a software tool, used to assess economic values and the environmental impacts of floating offshore wind farms. The assessment is based on life cycle analyses, which include five development stages: pre-development, manufacturing, assembly and installation, operations and maintenance, and decommissioning.

This tool is designed to help stakeholders such as wind farm developers and policymakers in decision-making processes in FLOW development. The aim is to enable the effective optimization of the maximum energy yield from any proposed development locations, while minimising the carbon intensity, associated net environmental impact and cost of electricity generation.

A holistic model has been established to encapsulate the whole procedure in assembly and installation of FLOW, including the transport of major FLOW components (tower, blades, nacelle, mooring system, cables, and floating platforms) from manufacturing port to assembly port. This involves the assembly

of wind turbine generators at assembly port, the transit from assembly port to installation port, and the installation at the farm site.

The installation tasks are classified into four categories, i.e., assembly at the port, offshore installation, installation on the seabed, and onshore installation. Three assembly activities at ports or shipyards are considered, including wind turbine assembly, storage of mooring chains, and storage of anchors. The offshore installation includes the transport activities from manufacturing to assembly port, transport activities between installation port and to farm site, as well as offshore operations for installing wind turbines and the mooring system. Installation on the seabed considers the installation of inter-array and export cables, being the cables connecting the wind turbines to one another.

Lastly, onshore installation is dedicated to the installation of onshore substations and export cables. Various types of vessels are employed for the installation of components, such as tugboats, cargo vessels and crane vessels, dependent on specific tasks. The impact of weather conditions on maritime operations is considered by simulating the vessel transit and operation time for wind farm installation, maintenance, and end-of-life decommissioning operations. Additionally, the fuel consumption rates of each vessel for vessel transit and operation are considered separately. A similar environmentally conscious approach is deployed for the analysis of FLOW decommissioning, where the research team considers the recycling and recovery of materials at end of life.

During the maintenance life of the floating offshore wind farms (approximately 25 years), approaches are being taken to account for uncertainties in the failure of them operating effectively. Statistical techniques are being used to determine any uncertainties in the development of the models. The team is currently exploring surrogate-based methods and representative learning approaches to achieve an effective trade-off between computational cost and model fidelity. The hope is to ensure the simulator can be used commercially and by policymakers, to inform investment decisions and future offshore industrialisation, both with confidence and within reasonable timeframes. The impacts of metocean conditions at various locations on vessel accessibility and transit time are determined for all of the offshore operations. This is to ensure the generation of real-world results in terms of both economic costs and carbon emissions. Only by adopting the “cradle to the grave” approach outlined can stakeholders be assured that the major impacts are being captured for any individual wind farm development or series of developments.

3 Cradle to grave life cycle model (University of Exeter, 2022)

Once fully developed and implemented, this tool will allow the optimisation of wind farm design and the planning of multiple windfarms at regional spatial levels. Consideration will be taken into the potential impact of installation, decommissioning, and marine maintenance operations on marine-based flora and fauna. Additionally, solid metrics will be determined on the lifetime costs of energy production, the lifetime carbon costs, and the total energy returned as a ratio to the total energy invested at an individual farm level.

There is a proposed extension of the tool, to further support the modelling of seabird habitat use and how they interact with wind farms. The aim is to use the existing tool to test a series of different wind farm configurations (orientation, spacing of turbines, etc), to provide guidance on those designs that give economic yields, while at the same time minimising their impact on seabirds. Investigations could be taken to discover how to mitigate against the potential losses of birds to wind farm installations by compensation mechanisms, such as the creation of new breeding areas, bycatch reductions methods, or invasive species eradications. The final tool output can inform the creation of a UK-wide risk map that highlights areas around the UK where wind and seabird interests align, to inform wind-farm planning and development policy at a national level.

Having a tool that allows developers and policyholders to virtually explore the interactions between one or more farms at a sea-scape level, enables us to plan wildlife corridors within a farm or between farms, enabling populations to flourish. The approach can inform where and where not to develop and evaluate the associated impact on the cost of generation and energy yield. Generally, this tool will provide valuable information to further inform policy decisions and potentially drive investment in the local supply chains. Multiple scenarios can be evaluated within the simulator, enabling the alignment of low carbon power generation, with the development of local content manufacturing, assembly, and marine operations supply bases. This tool has great potential to help guide environmental impact assessments, whilst also providing a source of energy across the region.

Many thanks to the floating offshore wind simulator team at the University of Exeter for contributing this research to and the Cornwall FLOW Accelerator for leading this project.

References:

1. Team photo for the Exeter floating offshore wind simulator team Image taken at the University of Exeter, Penryn, Cornwall, 2022

2. Sweden’s Hexicon buys consented Celtic Sea site for floating wind demo. Renewablesnow.com. 2022. Available from: https://renewablesnow.com/news/swedens-hexicon-buys-consented-celtic-sea-site-for-floating-wind-demo-749519/

3. Cradle to grave diagram, created by the University of Exeter, 2022.

International Day for Climate Action: How I attended a conference remotely

ee320 Leave a comment

To celebrate the International Day for Climate Action, and the 10 year anniversary of its creators 350.org, we have been chatting to Louise Rutterford, a PhD student studying the response of marine systems to climate change at the University of Exeter. Louise recently presented a poster at conference remotely, from the comfort of her own home. 

Here she shares her experiences:

In early September I presented a poster at the annual International Council for the Exploration of the Sea in Gothenburg virtually (by skype). The session was a great success, not least due to the great support from the ICES team and hosting venue. I caught up with existing colleagues, met some new faces, found a new team working on similar projects to me and received the all-important constructive criticism of, and advice about, my work – so all the great bits conferences offer in a snapshot!

The session worked really well because the host organisation were keen to test this as a way to reduce travel and were totally on board with the set up. And I was kept busy as colleagues highlighted relevant parts of my work to each other and encouraged people to come and find me.

The session felt pretty intense from my end as I was tied to the screen, so no forays to the bar to absorb ideas and pointers for me! But everyone who spoke to me was incredibly supportive and, as usual at conferences, open to discussion, providing advice and helping to explain challenging concepts.

The set up at the conference venue.

I chose to attend the conference remotely for 2 reasons.

Primarily, I, Exeter and Bristol universities know that we need to radically reduce our impacts on the environment, especially our emissions. By not travelling to the conference I have conservatively reduced my research-based emissions by about 326kg [1] and [gwr.com] and saved about £900 of project funds in total.

Secondly, I have 2 young children and work part-time – it wasn’t realistic for me to travel to the conference and support my family during my sons first week at school. Attending the conference remotely meant I didn’t have to choose between work and family at this important time.

I do appreciate that by not attending the conference in person I missed hearing about new research from others as I couldn’t see the presentation sessions (something the event hosts hope to do in future) and developing relationships and projects with colleague over several days. However, I do feel that I was able to benefit from the conference experience as a remote attendee due to the openness and enthusiasm of colleagues in engaging and sharing ideas with me. Thank you ICES!

 

So, on to the practicalities!

Initially I planned to attend the conference and submitted my abstract as normal, through the web portal.

Once I had been accepted to present my poster I notified the conference hosts that I was keen to trial remote attendance, well before the application deadline. The hosts responded promptly and positively. As I was a guinea pig and the only link was for the poster session they agreed to waive the conference attendance fee in full.

The session relied on the openness of the hosts to set up a remote link and provide equipment. Next to my poster they supplied a laptop, high table and headset with a speaker. And on the day we tested the technology was working before the session started. I was set up in a quiet and well lit room with a strong internet connection (See above image).

To encourage people to come and talk to me I used the event #hashtag on Twitter to share my research and to encourage people to come and find me (on-screen!). In addition to this my presence and the relevance of my work was shared with appropriate people by word of mouth during the session (my thanks to the pushers!).

Louise used social media and the conference hashtag to encourage people to visit her and her poster

 

At the end of the session the team from ICES came and had a debrief chat which saved me from waiting for more delegates when they’d all headed out to the pub…!

I was busy talking to people for most of the poster session and alongside meeting people outside of my specialism, who provided a novel perspective on my work, I also connected with at least 5 people who are well equipped to critique and help to develop my work alongside theirs, some of whom I am in touch with, and picking the brains of, still.

#greatfortheplanet #greatforfamily #stillgoodforscience

Louise was still able connect with other delegates while attending remotely

For future opportunities like this it would be good to:

  • Make sure the internet connection is really strong as a few times the screen froze and conversation was disjointed.
  • Provide sound cancelling headphones with a speaker at the conference end to ensure delegates could hear over the hubbub.
  • Use a reliable courier service for the poster to be sent (Post Office failed me this time… but the venue (Gothia Towers) team pulled it out of the bag – THANK YOU!)
  • Include sign-posting to highlight the presenter on the screen so that people know where to look (mine was lost with the poster…)
  • Encourage use of the text messaging facility of the call service – this was a great way to get accurate spelling of names and links to papers etc. You can’t see past the shiny reflections on name tags.
  • Possibly host remotely presented posters in a small, low echo space so that people at the conference end can hear – as long as delegates are encouraged to use the space and engage.

Thanks Louise! 

You can keep up to date with Louise’s work on Twitter @LouRutters

#ExeterMarine is an interdisciplinary group of marine related researchers with capabilities across the scientific, biological,  medical, engineering, humanities and social science fields.

Find us on: Facebook : Twitter : Instagram : LinkedIn  

If you are interested in working with our researchers or students, contact Michael Hanley or visit our website!

 

References:

  1. Eco passenger. 2019 [cited 2019 14.10.19]; Available from: http://www.ecopassenger.org/bin/query.exe/en?ld=uic-eco&L=vs_uic&seqnr=3&ident=33.0267491.1571047646&OK#focus.

 

A Day in the Life of an Arctic Field Scientist

ee320 Leave a comment

Words by Clara Nielson, University of Exeter PhD Student

A day in the life of an Arctic field scientist

Hello! My name is Clara Nielson and I am a PhD student from Exeter University studying the impacts of global change on marine species in Dr Ceri Lewis’s lab. We are currently at 78 degrees north in a place called Ny Alesund, in Svalbard at the UK NERC Arctic Station for AXA XL Arctic Live with Encounter Edu. We are here to both conduct important research but also to communicate what we are doing to schools around the world.

Clara Nielson and Dr Ceri Lewis in the Arctic

Pulling open the curtains to a view of snow covered mountains and glaciers on the edge of a fjord will guarantee to put a smile on your face and put you in a good mood for the rest of the day. Our usual day starts waking up in the base and heading to the canteen for breakfast. Ny Alesund is home to a range of international scientists all coming and going at different parts of the year and the canteen is the communal hub where everyone can share a meal, and a story or two, before heading off for the day.

Arctic View

Weather permitting (we have had a few base days where we are unable to get out onto the boat due to high winds) we usually spend the day out on Teisten, the research boat, collecting water samples from different parts and depths of the fjord. We are out here to monitor the pH and carbonate chemistry of the seawater, as part of a global ocean acidification project. Ocean acidification is the change in ocean chemistry as a result of increasing atmospheric carbon dioxide levels and this process is happening fastest in the Arctic. The samples we are taking will help fill in the global picture of just how fast this process is happening. We are also sampling for any microplastics that may be in the seawater as the Arctic is also thought to be a hotspot for microplastic accumulation due to ocean currents. We were here last year doing the same sampling, and we did find some plastic, so it will be really interesting to compare our data and that of other long term projects to see how the Arctic is changing. Today it was -7oC, which is pretty cold but add to that the wind chill and we were out in temperatures of about -25 oC. This made sampling slightly trickier than at home as the seawater and all of our sampling gear was freezing pretty quickly, not to mention how cold my hands were getting! Its hard to describe how that sort of temperature feels but basically it’s painfully cold. Thankfully team work, biscuits and a kettle kept everything working!

 

The cold is soon forgotten as once the days sampling is over we can head back to our heated base but the hot shower has to wait just a little longer! First, we need to make sure all our kit is cleaned ready to go again tomorrow and the samples are stored away correctly.

After dinner we spend a bit of time looking through samples and manage to show our Arctic base manager Nick his first sea angel! This is a type of zooplankton called a pteropod, which flapped around our petridish and made this seasoned field man swoon at its beauty.

Frozen equipment is a daily challenge.

Before bed I spend a bit of time with Jamie, from Encountered Edu, going through what I shall be doing tomorrow as it is my day to take part in Arctic Live. Arctic Live is the other important reason we are all here, as alongside our research we are taking part in a live streaming educational lessons and question and answer sessions where we speak to school children live from around the world about our experiences and answer their questions about the Arctic and what it is like to work here. I am looking forward to hearing what questions the children have come up with! Its really cool that we can share what we are doing live from this amazing place, I hope it inspires them.

It is time for bed once we are all set for tomorrow, the 24-hour daylight is making it slightly harder to get to sleep as you feel like it should be the middle of the afternoon, not 11pm but it is important that we all get a good rest.

I feel very privileged to be out in such a stunningly beautiful place and it is without doubt the best place I have ever done field work in. The wildlife here is amazing too, today we saw a Minke whale from the end of the boat which was incredible. The Arctic is at the forefront of climate change where the impacts are being felt first and fastest and is also a hotspot for plastic pollution so it is probably the most important place to be doing this kind of science right now.

All images a courtesy of Jamie Buchanan-Dunlop of Encounter Edu.

#ExeterMarine is an interdisciplinary group of marine related researchers with capabilities across the scientific, biological,  medical, engineering, humanities and social science fields.

Find us on: Facebook : Twitter : Instagram : LinkedIn  

If you are interested in working with our researchers or students, contact Michael Hanley or visit our website!

 

My #ExeterMarine PhD: Clams and Climate Change

Michael David Hanley Leave a comment

Author – Sarah Holmes, PhD Researcher – Geography and Earth System Science

Arctica islandica (also known as ocean quahog) clam shells. Oldest animal known to science, abundant and widely distributed throughout North West European Shelf.
Photograph by Thom Holmes [thomholmes.co.uk].
Yes, clams.

Admittedly, telling people that my PhD research is using clams doesn’t always get “ooo’s” and “aah’s” that perhaps my fellow researchers working on whales and dolphins might get, but before you write me off as having a boring PhD, let me tell you a few…

**CLAM FACTS**

 

  1. Clams are the oldest animal known to science. Certain species are extremely long-lived. In 2006, scientists at Bangor University (these scientists have now moved to the University of Exeter, Penryn Campus) found a clam that was 507 years old. 507! That means this humble little mollusc (see picture above) was around when Shakespeare was putting pen to paper, when Henry VIII was beheading wives, when your great-great-great-great-great grandparents were born!

 

  1. Clams can record information about the environment in their shells. Certain species form annual growth bands on their shells, just like tree rings. During winter months, the clams grow more slowly and build up a denser layer of shell that looks like a defined band under the microscope (see picture below). Just like trees, the amount a clam (and so its shell) grows depends on the environment it lives in. In general, warm temperatures and plenty food (e.g. algae) means lots of growth and so a wide growth band. The opposite is true in less favourable conditions such as low temperatures or lack of food. As you may already know, using tree records in this way is called dendrochronology; using clam records is called sclerochronology.

    Microscope image (25x mag.) of acetate peel of internal portion (umbo) of clam shell (species Glycymeris glycymeris). Clear growth bands visible, yellow line shows direction of growth (d.o.g).

 

  1. Clams in the same area grow synchronously. Since clam growth is affected by environment, it makes sense that clams from the same location (that are affected by the same environmental conditions) have very similar growth patterns. This means that it is possible to match up and combine the growth records of multiple clams to create what is called a ‘master sclerochronology’ – you can even incorporate ‘dead-collected’ clams that have an unknown date of death.

 

Cool, right? Well even more interestingly, these features mean that clams are an extremely valuable proxy* for the marine environment and are therefore of great interest to climate scientists like me. Previous research has shown that the clams are recording a multitude of environmental information in their shells such a sea water temperature, the amount of plankton present in the water and even large-scale climate variability such as North Atlantic Oscillation (which is like a measure of storminess in Northern Europe). Researchers can therefore (to an extent) reconstruct past ocean conditions using these records.

Clams also look really beautiful under the microscope (photographs of Glycymeris glycymeris by Thom Holmes [thomholmes.co.uk])
It is of vital importance to know how the ocean has changed in the past as this can help us understand how it might change in the future, especially considering the many threats of climate change. The shelf seas (the shallow oceans that surround the land, e.g. the North Sea) are hugely important as they sustain the majority of global fisheries (the North Sea is a major UK fishing ground) and are the main way that we interact with the marine environment (e.g. tourism). Although we do have some direct observational measurements of the shelf seas available, these are both spatially and temporally limited.

Scientists generally use shelf sea models** (of places like the North Sea) to predict future change, however to check if these models are representing reality correctly, they must be compared or ‘validated’ with these limited observed measurements.

Therefore, for the first time, my research is attempting to combine the records of long-lived clams with ocean models in order to better understand past and future change in the North Sea. The aim is twofold – first, to use the clam records to better validate the model and second, to use the model to give greater insight into the factors controlling clam growth in order to better interpret these proxy records.

So, I think we can all agree, this humble little clam is pretty exciting and could hold the key for better predictions of future ocean climate change – not bad for a squidgy, slimy lump that doesn’t even have a brain!

*Proxies are indirect measurements of the environment preserved in natural recorders of climate variability such as tree rings, pollen, ice cores or the rings on marine clams.

** Models are mathematical representations of the real world. Ocean models such as the one I am using (the European Regional Seas Ecosystem Model (ERSEM)) attempt to quantitively describe the physics, chemistry and biology of the shallow ocean that surrounds Europe (known as the Northwest European shelf seas).

#ExeterMarine is an interdisciplinary group of marine related researchers with capabilities across the scientific, medical, engineering, humanities and social science fields. If you are interested in working with our researchers or students, contact Michael Hanley or visit our website!

Changing storminess and global capture fisheries

Michael David Hanley Leave a comment

Author – Nigel Sainsbury, PhD researcher, Environment and Sustainability Institute

Potential changes in the frequency and intensity of storms over the world’s oceans could have a catastrophic impact on global fisheries, risking the lives, livelihoods, food security and health of billions of people around the world.

In a new commentary article published in Nature Climate Change, I argue, along with my co-authors from ExeterMarine, Cefas, Willis Towers Watson, Met Office and the University of Bristol, that a new global research effort into changing storminess and global capture fisheries is required to help fisheries adapt to this aspect of climate change. We outline a research roadmap encompassing aspects of climate modelling, fisher behaviour, marine ecosystems and fishery vulnerability and adaptation.

There is growing evidence that storminess will alter in the future with climate change. There are great uncertainties in both future predictions and reanalyses of historic storms, owing to a lack of historic data and the limitations of storm representation in climate models. Whilst the number of studies is growing in both number and coverage of the world’s ocean basins, research is required to develop projections of future storminess at local scales with significantly more confidence.

Storms have the potential to cause extensive socio-economic impacts on fisheries. It is estimated that every year, night-time thunder storms kill between 3,000 – 5,000 fishers every year on Lake Victoria. When Cyclone Nargis struck Myanmar in 2008, 28,000 fishers were killed or missing and over 100,000 fishing boats were destroyed. Closer to where I am based, at the University of Exeter’s Penryn campus, the winter of 2013-2014, the stormiest on record, caused an estimated £7 million loss of income, £400,000 in lost fishing gear and £1.1 million in fisheries onshore infrastructure damage.

Our knowledge of how storms impact marine ecosystems is limited. There is evidence that storms damage mangrove forests, seagrass beds and corals and cause the redistribution of fish and mass fish mortality events. However, this is taken from a handful of studies. Research is required in different ecosystem contexts around the world to identify how storms will impact ecosystems and how this links to socio-economic impacts on fisheries.

Changing storminess differs from other climate stressors affecting fisheries, such as ocean warming and acidification, because it has a direct social dimension as well as causing ecological impacts on target fish species. Whilst a myriad of social and economic factors have been shown to affect fishers’ decisions about where and when to fish, the role of weather in fisher behaviour has received little attention. Exploring how fishers perceive weather risks and how the uncertainties of physical danger and financial outcomes factor in fishers’ decision making in different social and cultural contexts will be important to predict the future fishing disruption caused by changing storminess.

If the scientific community is to help fisheries adapt to changing storminess, research into the ecological, socio-economic and climate aspects of changing storminess must translate into assessments of fisheries vulnerability to this environmental change.  This will support national governments in assessing the threat their fisheries face and, if required, help them to prioritise where to focus adaptation efforts. Social scientists can also support this effort by identifying and evaluating adaption actions in different contexts. Financial mechanisms currently being used in terrestrial agriculture to improve farmers’ resilience to environmental shocks, such as drought, may offer potential. It must also be considered that fisheries in areas of projected reduced storminess may experience an increase in potential fishing days, bringing socio-economic benefits but also increasing the challenges of unsustainable natural resource use.

#ExeterMarine is an interdisciplinary group of marine related researchers with capabilities across the scientific, medical, engineering, humanities and social science fields. If you are interested in working with our researchers or students, contact Michael Hanley or visit our website!

My #ExeterMarine Expedition: updates from the Indian Ocean

Michael David Hanley Leave a comment

This is a series of updates from #ExeterMarine researcher, Dr Ines Lange, who is on a research expedition in the British Indian Ocean Territory with Professor Chris Perry, the Bertarelli Foundation and ZSL.

Hard at work in the Indian Ocean

03/05/2018 Somewhere in the Indian Ocean

We are in the Central Indian Ocean, sailing south on the “Grampian Frontier”. Prof. Chris Perry and myself, Dr. Ines Lange, from the Geography department are on a research cruise to study the coral reef ecosystems of the British Indian Ocean Territory (BIOT). The project is part of a large expedition funded by the Bertarelli Foundation and on board are twelve scientist, working on six different projects.
Chris and I are studying the carbonate budgets of coral reefs around islands of the Chagos archipelago. The “ReefBudget” method we use was developed by Chris and calculates how much carbonate is produced by corals and calcifying algae, and how much is eroded by grazing sea urchins and fish, as well as by internal bioeroders such as boring worms and microorganisms. The results provide a metric of reef “health” in terms of whether it is growing or eroding. On this trip we have two main goals:

1) To revisit sites that were surveyed in 2015, before the severe bleaching event that hit the Central Indian Ocean in 2016. We expect to see dramatically reduced rates of carbonate production due to low coral cover.
2) To investigate local rates of coral and calcifying algal growth as well as internal erosion rates by deploying experimental substrates.

On the two-day transit from the Maldives down to Chagos we are busy preparing material for the deployment of experimental substrates and discussing calculations for the model. Of course we also have to include a few safety exercises; it is very hot here so I would not mind going for a swim, but we ended up not abandoning the ship…

Stay tuned for our upcoming adventures underwater.

Survivors in the reef

News from the “Reef team” in the Indian Ocean. The sites in the Salomon and Peros Banhos Atolls we visited so far show a dramatically reduced coral cover due to the severe bleaching event in 2016, causing carbonate production rates to drop to about a third of the values in 2015. On the upside, there are many Porites and also some Acropora colonies that apparently survived the bleaching, and large numbers of small recruits of different genera. Especially in the understory of the reef structure we find many live encrusting corals. Also, the substrate is quite clean of macroalgae, thanks to the high abundance of grazing herbivorous fish. Calcareous algae covering the dead coral substrate continue to produce substantial amounts of carbonate which help “glue” the existing structure together and offer a great substrate for further coral recruitment. We therefore hope we can see a fast recovery of the once glorious reefs over the next years.

To investigate local bioerosion rates in the reefs we had a “fun” day sawing 1000s of blocks from dead Porites skeleton (well, it certainly felt like that, on my last count it was actually 28). Today we successfully deployed the substrates in the reef, where they will be settled by encrusting and bioeroding organisms (or eaten by parrotfish? Hope not …). The work days are long and it’s actually not always as sunny as you would imagine (see how we enjoy our surface interval in the rain?!). But the company is great, and encounters with curious turtles, dancing eagle rays and confused birds trying to land on our heads make every day a great adventure…

#ExeterMarine is an interdisciplinary group of marine related researchers with capabilities across the scientific, medical, engineering, humanities and social science fields. If you are interested in working with our researchers or students, contact Michael Hanley or visit our website!

Life on a Russian Icebreaker: ACE Maritime University

Michael David Hanley Leave a comment

Author – Jen Lewis, PhD researcher

This blog originally featured on fabiogeography.com.

Before departure in Bremerhaven Germany

Last year (I can’t believe it’s been a whole year!) I was lucky enough to be awarded a scholarship to attend a one off opportunity, the ACE Maritime University. The scene for this month long ‘floating university’ was the Eastern Atlantic Ocean, aboard the Russian Polar Research Vessel Akademik Treshnikov.

On the 19th of November 2016, 49 students and 16 scientists from 20 different nationalities joined the ship in Bremerhaven, Germany for Leg 0 of the Antarctic Circumnavigation Expedition. Over 27 days we sailed down across the equator, to Cape Town, South Africa. ACE was a

privately funded expedition, that went on to circumnavigate the continent of Antarctica last summer, visiting the islands, measuring things like marine mammal populations, ocean acidification, carbon dioxide dynamics and marine plastic distribution. There were 22 different research projects, and if you want to read more about them then check out the ACE expedition website and blog.

The aim of the course was to bring together a global group of young researchers and introduce marine science as a cross-disciplinary field. Days were full of lectures on various principles of oceanography, or how to use different type of ocean monitoring instrumentation.

Releasing a radiosonde balloon to take atmospheric measurement

 

Deploying the CTD and water sampler

 

 

 

 

 

 

 

 

 

 

We even had homework every other day! We also took part in daily deck work with the different projects that were setting up for the Antarctic legs. This included things like assisting with the CTD deployment, processing data, collecting water samples and filtering them. Highlights included working with Florian and Yajuan to make a film about their research  investigating microbial and plankton communities that have big influences on primary production and the carbon cycle, seeing the different layers of biomass on the echosounder display, and also setting up and deploying a radiosonde balloon that measures the atmosphere.

Dolphins riding the bow waves

 

CTD profile from cruise data. Each graph shows information about temperature, salinity or oxygen from the surface down to 1000m depth. Samples start from near the Mediterranean (CTD001), over the equator (CTD10) and further south towards the African coast. You can see things like the high salinity Mediterranean outflow at the start, and oxygen minimum zones either side of the equator.

As part of a personal project, I was also filtering seawater samples from different depths from the CTD casts every day. These samples are being used to look at the difference in species diversity through the North to the South Atlantic, by looking for traces of DNA that has been left in the water by different species that are in the area at different depths – so watch this space!

#Research: Testing new mooring systems for #MarineRenewableEnergy

Michael David Hanley Leave a comment

Author – Dr Tessa Gordelier

A new paper has been published by #ExeterMarine academics Prof. Lars Johanning, Dr Tessa Gordelier and Dr Philipp Thies in collaboration with the French research institute IFREMER (@Ifremer_en).

The mooring systems were put through their paces at the University of Exeter’s DMaC facility

“Assessing the performance durability of elastomeric moorings: Assembly investigations enhanced by sub-component tests”  investigating novel mooring tether performance for offshore renewable applications.

The growing marine renewable energy sector is placing new demands on mooring systems; not only are they required to hold devices on station they must also provide the compliance required to harvest energy from the marine environment.  In response to this, several innovative mooring tethers have been proposed, with increased compliance and a degree of customisation of the stiffness profile.  Many of these novel systems utilise materials in a unique application within the challenging marine environment and their long term durability remains to be proven.

The novel mooring system underwent 6 months of sea trials on a mooring limb of the South West Mooring Test Facility

In response to this challenge, the work presented in this paper summarises a multifaceted investigation into the durability of a novel mooring tether with an elastomeric core.  Tether assembly testing is conducted before and after a 6 month sea deployment in addition to detailed laboratory investigations.  At a sub-component level, to represent the operational demands of the tether on the elastomer core, detailed material investigations review the effect of both marine exposure and repeated compression loading on key material properties. This work is the first of this type to be published and will be of interest to anyone utilising this material in other relevant applications.

Overall the results indicate an increase in both material and tether stiffness profile with use; this will affect both system dynamics and mooring loads.  If we are to realise the benefits of these novel mooring systems, this characterisation is crucial to ensure reliable and effective integration into offshore engineering projects.

#ExeterMarine is a interdisciplinary group of marine related researchers with capabilities across the scientific, medical, engineering, humanities and social science fields. If you are interested in working with our researchers or students, contact Michael Hanley or visit our website!