Field work

Our [student] Life on the Ocean

Posted on May 31, 2023June 13, 2023 by Hannes Baumann

By Ewaldo Leitao.
When we say we work or study oceanography, it is common for us to be met with a: “Wow, you must spend a lot of time doing cool stuff in the ocean then!” Alas, most of us spend most of our time on a computer. However, cruises are still an essential part of oceanographic research to collect the necessary data or test equipment. In our department, many students have this opportunity to participate in such cruises; all with fascinating and unique research interests. Over the past year, several students joined cruises to get familiar with field techniques, collect their own data, or to better understand their study area. In this piece, graduate students in our Marine Sciences department shared their experiences in cruises that took place from Summer 2022 up to May 2023.

“In the Summer 2022 I participated in the Sea Education Association (SEA) summer cruise through the great pacific garbage patch, which sailed from Honolulu, HI to San Diego CA, starting In late June and ending in late July. SEA typically runs programs with undergraduates, who take part in cruises to learn about oceanography, sailing, and earn course credit. As a grad student, I was able to tag along as a visiting scientist and focus on collecting data.

My research focused on taking optical measurements, such as spectral reflectance, of freshly-collected plastic pieces. Previous work has been published on plastic spectral reflectance properties, but these measurements were made on dried and stored samples. Out in the environment, plastic pieces are likely to have some degree of biofilming growing on them. So, I sought to collect spectral reflectance measurements of freshly collected plastics in order to assess how the presence of biofilms might impact plastic spectral reflectance. Knowing this will be useful for sensitivity analyses seeking to develop a satellite-based ocean plastic detection algorithm.

During the cruise, I conducted daily neuston net tows to collect plastic pieces. Neuston nets are towed along the surface of the water to collect as many buoyant plastic pieces as possible. Once collected, I rinsed the plastics out of the net and into a bucket, then picked them out and aggregated them for spectral measurement.”

“I participated in NASA’s Sub-Mesoscale Ocean Dynamics Experiment (S-MODE) IOP1 as part of the science party aboard the R/V Bold Horizon. The cruise took place from 10/06/2022 – 11/04/2022 in the Pacific Ocean, approximately 100 miles offshore of San Francisco, California. The focus of this experiment was to sample ocean fronts that are a few kilometers in size to study their dynamics and effects on vertical transport. The ocean fronts were sampled using aircraft, ship surveying, and autonomous platforms such as wave gliders, sea gliders, saildrones, floats, and drifters. I worked the night shift from 4pm – 4am, running an instrument called an EcoCTD, which measures temperature, salinity, pressure, chlorophyll, backscatter, and oxygen. I also helped with the recovery and deployment of wave gliders and mixed layer floats.

I am currently (03/06/2023 – 04/06/2023) aboard NOAA’s R/V Ronald H. Brown for U.S. GO-SHIP’s decadal reoccupation of A16N in the Atlantic Ocean. I am participating in the first leg of the cruise, sailing from Brazil to Spain. The second leg of the cruise will be sailing from Spain to Iceland. This is a longline hydrographic cruise, where we take CTD casts at many stations along the same longitude line. The CTD rosette has 24 bottles and is deployed to the bottom of the ocean. I am working with Dr. Chris Langdon’s research lab out of the University of Miami. The Langdon lab is leading measurements on oxygen, pH, and total alkalinity. I am overseeing pH measurements using a spectrophotometer. Other groups are taking measurements which include DIC, DOC, CFCs, velocity, temperature, salinity, and biological samples. The best part of my trip so far has been getting to explore Brazil, crossing the equator, and viewing beautiful sunrises every morning.”

Yipeng He, alumnus of the Mason Mercury Lab, studied air-sea mercury exchange in the ocean for his PhD, also had cool research experiences in cruises.

“I was on a scientific cruise - the GEOTRACES GP17 cruise, leaving San Diego (CA) on Nov 13 2022. Going from North Pacific to South Pacific, crossing the Equator, going further south and crossing the Antarctic cycle, and arriving at Punta Arena (Chile) on Jan 25 (2023). The boat was R/V Roger Revelle, which was my second time sailing on this boat. The first time was the GEOTRACES GP15 cruise in 2018. I was collecting samples and measuring atmospheric mercury species, air-sea exchange of mercury species and surface ocean Beryllium-7 profile.”

Heat tolerance changes across environments and populations

Posted on March 27, 2023March 27, 2023 by Hannes Baumann

March 27th 2023 - By Ewaldo Leitao.

Climate change is a threat to species persistence. Increasing temperatures affect species differently depending on their habitats, such as land or the ocean. However, species often consist of different populations (groups of individuals that reproduce together) that experience different temperature conditions. And if populations live in these areas long enough, they can genetically adapt to their local conditions. What does that mean? If the same species has a population in an area where it is constantly warm, like the tropics, and another population that lives in colder regions, like Connecticut, then we’d expect the tropical population to handle high temperatures better compared to the population living in colder regions. This kind of diversity within species affects how we think about the vulnerability of the species as a whole. To add another layer, if variation differs for terrestrial vs. oceanic species, we might be missing important information about where climate change will have the strongest effects on the planet.

That is what Dr. Matt Sasaki and collaborators investigated in a paper recently published in Nature Climate Change. Their main goal was to assess the heat tolerance (the highest survivable temperature) of populations in many different species, from different realms – terrestrial, freshwater, marine and intertidal. They assessed the vulnerability of species by surveying in the literature from the whole world that measured individual heat tolerance. They compiled and then conducted a meta-analysis of these published data, thereby assessing how the heat tolerance is related to the thermal environment these populations live in.

“This paper came out of the ‘Evolution in Changing Seas’ Research Coordination Network (RCN). Back in 2019 they brought some of us together at Shoal’s Marine Lab for a synthesis workshop and essentially told us to think about questions at the intersection of evolutionary biology and marine science”, said Matthew Sasaki, about the seed of the idea.

"I really enjoyed the collaborative aspect of this project, even though I’ve met most of the co-authors in person only once (or not at all!)"

By measuring how heat tolerance changes between populations of the same species, they found that marine and intertidal species show a decrease of heat tolerance between populations as the environment gets colder, but that was not observed in terrestrial and freshwater populations. This was an interesting result, because since the ocean is largely connected, they expected that there would be a smaller differentiation in the ocean compared to land, where geographical barriers can create physical separations, allowing difference in heat tolerance to build up among populations within a species.

Behavior may play a role in the observed patterns. In the terrestrial realm, many organisms can moderate body temperature by seeking shade and forested areas to find refuges from the heat. Even plants can exploit micro-climates. This decreases the amount of evolutionary pressure on terrestrial organisms, when compared to other realms.

This study highlights the importance of accounting for evolutionary processes in the context of climate change and species persistence and extinction risk. Larger differentiation of heat tolerance within species may suggest a potential for evolutionary rescue. That is, populations with genes that allow them to be “warm adapted” may rescue populations that are more susceptible to increasing warming.

We asked what was the coolest part about the execution and findings of the project. “This wasn’t a project someone could do alone, and it was really cool to be part of such a big collaborative effort. The findings themselves were also really exciting for us. We expected there to be pretty clear differences between marine and terrestrial taxa, but we were surprised to see that local adaptation seems to be stronger in marine species and not terrestrial species. This goes against some of the traditional paradigms (that marine species’ are more often homogenized by larval dispersal, for example), and hints at a cool role of behavioral thermoregulation in shaping patterns in evolutionary adaptation.”

“This was definitely a pandemic pet project. I won’t say the pandemic helped us make progress though. This ended up being something we worked on a little bit each week for a couple years. Maybe that helped us put together a more robust product (slow and steady wins the race?). I really enjoyed the collaborative aspect of this project, even though I’ve met most of the co-authors in person only once (or not at all!). Having to do everything virtually definitely changed the nature of the collaboration (more written exchanges, less whiteboard brainstorming) but I think we made it work. We’ve just started working together on a couple new projects that build from this initial work, so it must not have been too terrible.”, said Matt.

Sasaki M, Barley JM, Gignoux-Wolfsohn S, Hays CG, Kelly MW, Putnam AB, Sheth SN, Villeneuve AR, Cheng BS (2022) Greater evolutionary divergence of thermal limits within marine than terrestrial species. Nature Climate Change. 2022 Dec 1:1-6.

Sampling freshwater mussel gut microbiomes in the Great Lakes

Posted on March 17, 2023March 17, 2023 by Hannes Baumann

In June 2022, Hannah Collins and Tyler Griffin from the Ward Environmental Physiology Lab went to Buffalo, NY, to perform research on the gut microbiomes of freshwater quagga mussels (Dreissena bugensis). The three-day trip involved collecting these invasive mussels from Lake Erie with the help of Brian Haas at the Buffalo State Great Lakes Center field station. The goal of the project, funded by an NSF Emerging Frontiers in Research and Innovation grant, was to sample mussel gut microbes before and after defecation with the goal of distinguishing between microbes that live inside the mussels and other microbes that were simply passing through. This work serves as preliminary research for the larger goal of investigating the feasibility of using freshwater mussels to remove microplastics from freshwater systems and co-concentration them with plastic-degrading bacteria.

“Harmony of Nature”: environmental data becomes music

Posted on December 2, 2022December 5, 2022 by Hannes Baumann

By Ewaldo Leitao.

Science communication has many flavors, kinds, and sounds. One way by which that can happen is when nature or science produce “noise” that can be channeled into sounds. That can be done using architecture (Sea Organ), or reinterpreting a field of science (Quantum Computer Music). Sometimes, this combination of sound and science can be a deliberate choice, creating music.

DMS student Molly James and musician Hea Youn Chung (Sophy) combined their expertises and interests to explore this intersection between science and music. Molly plays trombone in her free time at a community orchestra. Sophy is a professional pianist and teacher at Yewon Arts School (Seoul, South Korea) who did her Master of Music degree in Piano Performance at The Juilliard School. What initially joined these two at the dead of the pandemic was a mutual language assistance: Molly wanted to learn Korean, and Sophy, back in South Korea, wanted to continue practicing English.

And that’s how “Harmony of Nature” was born. A beautiful collaboration that converts natural phenomena into sounds through coding technology and expresses them in classical music. The project was funded by the Art & Tech program by Arts Council Korea. The data was collected using temperature loggers deployed in several sites across South Korea, along with freely available data from several spots. “I statistically analyzed this data and created multiple graphs using the open-source coding language Python. I shared them with Sophy and discussed the scientific interpretations. Together, we collaborated on what scientific aspects became what musical aspects.” said Molly, about the process of data collection and curation, prior to its translation into music.

“Like expressing human emotions through musical instruments, I have always wanted to express natural phenomena that we cannot see but can feel through sound. While envisioning this project, I focused on conveying natural phenomena through sound.” said Sophy. “For various expressions, I try to incorporate nuances such as shape and texture into the performance. In this project, the weight of the waves, the ebb and flow of the waves, the temperature changes, and the appearance of rain can be realized by various musical elements such as rhythm, dynamics, etc.”

The composition “One Week in Incheon” directly came from hourly air temperature measurements collected at a weather station by the Korean Meteorological Administration Incheon branch 112. Other data, such as wave height, flow and ebb tides, were also analyzed in order to compose some pieces. “During this performance, I hope you can feel changes in temperatures, drops of rain, speed of the winds, and height of the waves”, says Molly. More songs can be found on Spotify or AppleMusic.

Science needs to reach out to the public, informing in different, inventive, artistic ways. Art is powerful. Collaborations between science and art will thrive as each part can use their unique skills to result in beautiful projects, such as this one.

Surveying ocean acidification on the Northwest Atlantic shelf

Posted on December 2, 2022December 2, 2022 by Hannes Baumann

By Ewaldo Leitao.

In August of 2022, Prof. Samantha Siedlecki and Prof. Craig Tobias, along with students Halle Berger and Alex Frenzel, went on the East Coast Ocean Acidification Cruise (ECOA-3). The cruise was led by scientists at the University of New Hampshire, joined through transdisciplinary partnerships with other universities, aboard the NOAA Ship Ronald H. Brown. The UConn Avery Point members joined the cruise to investigate the contribution of sediments to carbon chemistry and how that ultimately impacts ocean acidification.

Sam, Craig, Halle and Alex were the sediment coring team. The cores go all the way down to the bottom of the ocean and collect both the upper part of the sediment and the layer of water above it. This way, it is possible to understand chemical reactions in this zone between the sediments and the water above it. “The idea here is to understand how sediments control the chemistry of bottom water. There are sediment reactions that could help buffer acidity. But it's unclear how sediments talk to the water above it or how that communication might change in the future” says Craig. You can learn more on the Facebook page of research vessel Ronald H. Brown.

These measurements are valuable information because they are not only timestamps of what is happening at the moment of collection. Increasing the number of observations and fine-tuning the measurements of these chemical processes in bottom waters helps the research of modelers, like Sam. Models are important to test our understanding of ocean processes. We need more measurements like this to more accurately predict marine climate change. Part of Sam’s work is to use this information into regional ocean models to better constrain the role of sediments in the chemistry of the ocean.

Graduate student Halle uses modeling to understand how ocean acidification and warming impacts marine animals like Atlantic sea scallops. “I learned a lot about how all the different carbonate system parameters are measured, and it was great to meet other students and scientists working on ocean acidification. We got to see some whales and dolphins, amazing sunsets and starry nights, and ate a lot of delicious food. My favorite memory was at one station where all the multi-corer brought up was a single hermit crab (no sediment at all). We named him Fred.”, said Halle.

This was the third ECOA survey, which only happens every four years. The cruise starts in Newport, RI, travels to Portland, ME and then continues on to Nova Scotia. Traveling the Gulf of Maine, Georges Bank, Long Island Sound, Mid-Atlantic Bight, Chesapeake Bay, and the South Atlantic Bight. Each of these regions has their own physical processes that affect ocean acidification in each region, such as the Gulf of Maine receiving cold waters from the northern Labrador current and freshwater from rivers. In each of these regions, ocean acidification will likely have different effects. In the South Atlantic Bight, coral reefs, soft bottom corals, and therefore fish abundance may decline with ocean acidification. To better understand and accurately predict the impact of ocean acidification in different ecosystems, it is important to continuously do these measurements in order to understand how processes are changing over time in such dynamic environments.

Shell recycling will help restore oysters in Long Island Sound

Posted on November 7, 2022November 7, 2022 by Hannes Baumann

By Elaina Hancock.

7 November 2022. An unexpected find of a healthy, well-established oyster reef tucked away in a shoreline park inspired UConn Marine Science researcher Zofia Baumann to study ways to help these vital ecosystem engineers make a comeback.

Oyster habitats were largely destroyed by development, over-harvesting, and pollution, but in Long Island Sound, their numbers might be on the rise. Baumann and others hope to help restore Connecticut’s oyster populations.

Oysters build habitats where many species flourish, they improve water quality and make shorelines more resilient to erosion, but they need old shells to start building on. The site that became the focus of the project is one where oyster shells were deposited. Unfortunately, there is a shortage of shells in Connecticut and addressing this problem is the primary goal.

The project brings together members of the community, shellfish farmers, and regulators, as Baumann says, this effort relies on the community, otherwise, it will not work.

The Arctic is not so Boron!

Posted on September 21, 2022December 2, 2022 by Hannes Baumann

Professor Penny Vlahos investigates what happens with the ocean chemistry at the marginal ice zones in her recent publication

By Ewaldo Leitao.

The Arctic Ocean is undergoing rapid changes due to climate change. Increasing temperatures result in decreasing sea-ice extent, constant decreasing and thinning of permanent sea-ice caps. Some projections even show a completely ice-free Summer by 2050!

Another consequence of climate change is ocean acidification due to increasing atmospheric CO2. That leads to the decrease in water pH and changes in carbon chemistry dynamics. The Arctic may be a small ocean (3% of total oceans area) but it has an important contribution to carbon uptake (10%). Therefore, it is necessary to understand the impact of these changes across the oceans, including the Arctic, in order to be prepared for it.

Some chemical elements, such as boron, contribute to the ocean’s capacity to resist changes in pH, that is ocean’s alkalinity. Boron, in combination with salinity, has been used as a universal rule in the open ocean (boron to salinity ratio) in order to understand the contribution of boron to alkalinity, and therefore ocean carbon chemistry. But how does that change in the less saline areas, such as the marginal ice zones of the Arctic?

In the recent paper published in Nature Communications, Prof. Penny Vlahos and graduate student Lauren Barrett observed that, when measured in low salinity areas (marginal ice zones), the boron to salinity ratio deviates from the expected in open oceans. In a cruise that took place in May of 2021 (you can read more about the cruise here), researchers were surprised to find significant deviations in the boron to salinity ratios in ice and brine samples. Lower water temperature and lower salinity alters the exchange between boric acid and borate, which is used to determine the contribution of boron to sea water alkalinity (capacity of water to resist changes in pH and acidification), driving this deviation of the boron to salinity ratio compared to open ocean waters.

The unique microenvironment of the marginal ice zones creates a very dynamic system. As seawater freezes, salts are rejected, but there is still a liquid region between ice crystals, called brine channels. These channels allow boron to undergo inorganic changes that may result in the variations observed in some of the samples, increasing the variability of boron to salinity ratio observed in these Arctic areas.

Prior to boarding the research vessel, researchers had to quarantine for two weeks. But this was a valuable time to Lauren Barrett. “Over quarantine I spent a lot of time reading about the various uncertainties that other authors encountered in accurately and precisely constraining the carbonate system in this highly heterogeneous environment. The boron to salinity ratios that we present here warn against applying universal ratios constrained in the open ocean to marginal ice zones and ice environments.” says Lauren.

Lauren also shared a little bit about her experience: “I am very grateful for the opportunity to work with our international coauthors. The collaborative and interdisciplinary nature of marine science is one of my favorite aspects of working in this field. This research cruise was a great experience both personally and professionally, and I continue to be grateful to work in a field where cruising and getting to see polar bears is all in a day's work.”

The Arctic is an important sink of carbon and yet highly susceptible to climate change. Therefore, understanding detailed information of this system, instead of applying universal ratios, is necessary in order to better understand the carbon chemistry of the Arctic and be prepared for the consequences of climate change.