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Ruth is an MSc student in Geophysics at UBC, under the supervision of Dr Anaïs Orsi. She is looking at the changing climate of the Western Canadian Arctic, with a particular focus on the changes to the atmospheric water cycle. Understanding how the Arctic is changing is relevant to to our overall understanding of atmospheric dynamics, Arctic climate and will bring a greater knowledge of climate change to the people of the region, informing adaptation strategies.

Before coming to EOAS Ruth did her undergraduate degree at University College Dublin, Ireland, where she studied Astrophysics. She is passionate about increasing diversity within Earth Science and working to make science more accessible.

Critical Freshwater Fish Futures: using interdisciplinary and arts-based research approaches to engage relationships between Indigenous sovereignty and freshwater fish well-being

https://oceans.ubc.ca/2022-larkin-lecture/?login

Dr. Zoe Todd of the Department of Sociology and Anthropology at Carlton University will be speaking on the relationships between Indigenous sovereignty and freshwater fish futures in Canada, with an explicit focus on ongoing community-driven interdisciplinary research partnerships in Alberta, Saskatchewan, and Ontario. Drawing on decades of scholarship in the discipline of Critical Indigenous Studies that centres Indigenous sovereignty to elucidate relationships between Indigenous peoples and colonial nation-states and entities in Canada, this talk examines how an unambiguous engagement with Indigenous sovereignty, as understood through Indigenous legal orders and legal-ethical practices in Canada and internationally, can strengthen efforts to protect at-risk aquatic species and watersheds across the country. The use of arts-based research-creation approaches will be examined to help illustrate dynamic cross-disciplinary and pluralistic approaches of documenting, engaging, and upholding plural governance principles grounded in Indigenous sovereignties across many different homelands.

Dr. Zoe Todd (she/they) (Red River Métis) is a practice-led artist-researcher who studies the relationships between Indigenous sovereignty and freshwater fish futures in Canada. As a Métis anthropologist and researcher-artist, Dr. Todd combines dynamic social science and humanities research and research-creation approaches – including ethnography, archival research, oral testimony, and experimental artistic research practices – within a framework of Indigenous philosophy to elucidate new ways to study and support the complex relationships between Indigenous sovereignty and freshwater fish well-being in Canada today. They are a co-founder of the Institute for Freshwater Fish Futures (2018), which is a collaborative Indigenous-led initiative that is ‘restor(y)ing fish futures, together’ across three continents. They are also a co-founder of the Indigenous Environmental Knowledge Institute (IEKI) at Carleton University (2021). They were a 2018 Yale Presidential Visiting Fellow, and in 2020 they were elected to the Royal Society of Canada’s College of New Scholars.

The event will be a hybrid session taking place over zoom and in room the AERL Theatre (Rm. 120, 2202 Main Mall) at 6pm Nov 16. 

RSVP to the event and the post-talk reception here

Please note: UBC recommends masks be worn in indoor settings. Masks are especially recommended for those attending this session in-person, due to immunocompromised VIP. Masks and hand sanitizer will be available on site.

This month, EOAS assistant professor Anais Orsi and her team are headed to site D47 within the Adelie Land, one of the windiest places on Earth. The harsh conditions of the site, located on the steepest slopes of Antarctica, are precisely what brings the team to D47, where they will be investigating how strong winds shape Antarctic ice sheets and how gasses trapped in ice cores can be used to reconstruct previous wind conditions over the past 100 - 200 years. Scroll down to watch our interview with Dr. Orsi.

The fierce winds at site D47 form when very cold, dense air coming from the center of the continent falls down the steep slopes, creating what is known as ‘katabatic’ winds. These winds pick up and carry snow over the surface of the ice, forming snow dunes in their wake called sastrugi. While the size and orientation of the sastrugis indicate the direction and strength of the winds, they also cause the accumulation of snow over the ice sheet to be patchy, making it difficult to interpret shallow ice cores. As the winds continue to blow downhill, the air warms up and can hold more water vapor, causing the snow carried by the wind to evaporate. While it is clear this process results in a net loss of mass from the ice sheets, it is not yet clear how important this effect is on the ice sheet. Orsi’s team will study these effects using a water isotope laser spectrometer supported with an array of meteorological instruments to measure turbulence caused by the wind and associated moisture transport. 

A sastrugi formed in the Canadian Arctic. (Stock image)

To examine the longer term variability of katabatic winds, the team will extract 150 - 200 meter ice cores containing ice up to 100 - 200 years old. Air bubbles are trapped within the cores due to the porosity of surface snow, and contain a combination of lighter and heavier gas elements. When winds are calm, the heavy gasses sink to the bottom of the snowpack. By looking at the distribution of light and heavy gasses recorded in the ice core, Dr. Orsi hopes to reconstruct a timeline of previous strong wind events. These measurements will be the first of their kind, potentially providing greater understanding of katabatic wind variability over time. 

Following phase one of the expedition, the team will trek through the continent to a slightly less windy study site known as ‘Little Dome C’ where they will join fellow paleoclimatologists. Despite the milder winds, Little Dome C is even colder than D47, with temperatures as low as -40^oC. The oldest ice core to date, containing ice over 800,000 years old, was extracted from Little Dome C. However, paleoclimatologists are hoping to find even older ice to study the causes behind the changes in Earth’s ice age cycle periodicity. Previously, ice age cycles were regularly spaced every 41 thousand years, but since the mid-pleistocene transition, 1.5 to 1 million years ago,  they have become more intense (colder), but less frequent, returning every 100,000 years. CO₂ and other atmospheric gasses trapped in the ancient ice contain clues that can reveal the changes in Earth’s climate that precipitated this shift in ice age cycles. Dr. Orsai’s team will contribute to the project by characterizing how gasses become trapped in the ice at this particular site and how the milder winds affect the surface ice topography in this region. 

Kevin Xu Zhong, Jennifer F. Wirth, Amy M. Chan, and Curtis A. Suttle

Viruses are extremely abundant in the ocean and they play a major role in causing mortality of microbes, including heterotrophic bacteria and phytoplankton. It has been estimated that viruses kill about 20 to 30% of the living biomass in the ocean each day. But what specific microbial taxa are undergoing viral lysis in the ocean, given that there are thousands of them?

EOAS Research Associate Kevin Xu Zhong, along with his co-authors (Jennifer F. Wirth, Research Associate at Montana State University; Amy M. Chan, EOAS Research Scientist; and Curtis A. Suttle, EOAS Professor), tacked this problem by establishing the use of extracellular ribosomal RNA (rRNAext) (see the diagram below) to estimate taxon-specific cell lysis of microbes. Their work has just come out in the ISME journal on October 8, 2022 and they shared their story behind the paper in Nature Microbiology Community.

Conceptual diagram depicts the idea that cell lysis results in the release of extracellular rRNA (rRNAext)

“For years, we were surprised by large amounts of ribosomal RNA (rRNA) “contamination” in 0.22-µm filtered seawater that was used for viral studies," said Kevin. "We hypothesized that rRNA was released by cell lysis, and that this rRNAext could be sequenced to reveal the taxonomic composition of the cells that had died.” By conducting laboratory experiments with marine bacteria, their viruses and grazers (see below for experiment procedure), Kevin and his team confirmed that rRNA are released into the surrounding water by microbial cell lysis. This rRNA can be sequenced, i.e., MoRS - mortality by ribosomal sequencing, and used as a proxy for taxon-specific viral lysis.

Brief experimental procedure of the mortality by ribosomal sequencing (MoRS). The red dot indicates ribosomes

“Moreover, by standardizing to the cellular rRNA we have an index of cell lysis, relative to the amount of rRNA associated with each taxon, while the cellular rDNA provides a proxy for the relative abundance of each taxon,” said Dr. Suttle.

Kevin and his team also had many interesting observations in the project, such as high lysis was associated with taxa that were relatively rare (such as copiotrophs), while low lysis was often associated with taxa that were abundant, such as those in the SAR 11 group.

Kevin Xu Zhong

“MoRS offers a powerful new approach for understanding how taxon-specific lysis shapes microbial communities and processes, and provides an important tool in our efforts to explain the distribution and abundance of specific microbial taxa in nature,” said Kevin.

To learn the Behind the Paper story in Nature Microbiology Community: https://microbiologycommunity.nature.com/posts/extracellular-rrna-provides-a-window-on-taxon-specific-microbial-cell-lysis
Read the article here: https://www.nature.com/articles/s41396-022-01327-3

Brenda was born and raised in Lima, Peru, and has a Chemistry degree from the Pontificia Universidad Catolica del Peru. She also has a MSc and PhD in Geological Sciences from the University of British Columbia. Her PhD research focused on comparing water and carbon fluxes from different biomes (Amazon, Cerrado and Pantanal) and land uses (natural, agriculture, pasture) in Mato Grosso, which is a Brazilian state that has experienced extensive deforestation and land use and land cover change to produce different commodities such as soybean and cattle. Brenda is also a mentor and co-director of the research experience for Peruvian undergraduates (REPU) program, which is a non-profit organization that sets-up 3-month research internships for Peruvian undergraduate students in different institutions around the world. In her spare time, Brenda also enjoys reading mystery novels, hiking and watching movies.

Dr. Evan Smith, Dr. Maya Kopylova

In the BBC Future article on September 22, 2022, Dr. Evan Smith (Research Scientist at Gemological Institute of America, UBC EOAS Adjunct Professor) and Dr. Maya Kopylova (EOAS Professor) talked about their latest findings in diamonds, particularly, the super-deep ones.

Even the most ordinary diamonds are unique as they formed far deeper than any other rocks inside our planet and emerge to the surface. "There are no other materials at the surface coming from a depth of 600km [373 miles], absolutely not," says Dr. Kopylova.

In 2020, Dr. Smith studied a 124-carat super-deep diamond, which was found to form at least 660km (410 miles) below the Earth's surface and within the lower mantle at pressures at least 240,000 times those at sea level (240 times the deepest part of the ocean, the Mariana Trench). 

A lot of secrets about the Earth lie in super-deep diamonds like the 124-carat one, such as ancient carbon. Unlike regular diamonds, which are thought to start life from ancient seawater, super-deep diamonds start life as carbon dissolved within liquid metal, far down in the planet's interior. "It's like molten iron nickel alloy with sulphur and carbon dissolved in that," says Smith. "So it's a totally different kind of fluid, but it's still carbon fluid. It's undergoing whatever chemical or temperature changes, and that's causing carbon to crystallise out."

Most importantly, super-deep diamonds can provide important clues for the process of subduction, as they might be made of subducting tectonic plates that drifted down into the lower mantle in ancient times. "So we've seen diamonds that look like they're essentially pieces of the oceanic crust that have been carried down to the lower mantle," says Smith. "These diamonds are physically telling us that this process is physically true."

BBC Future: https://www.bbc.com/future/article/20220922-the-super-deep-royal-diamon…
Learn more about the UBC EOAS Diamond Exploration Laboratory: https://diamonds.eoas.ubc.ca/