Category Archives: Blog – presentations

Ocean Sciences Meeting 2020 (+ sunshine)

This week the Sed Lab has been in sunny San Diego at the 2020 Ocean Sciences Meeting. Conferences are a great opportunity to share research, hear fresh ideas, and learn about new opportunities. Evan and Andrea presented early results from Astoria Canyon. Robin presented posters for both her education research and the final chapter of her PhD (!!!), which examines particle aggregation and deposition in the Mekong River. Hannah gave two oral presentations, one on building a global scientific community and one on sediment dynamics in the Ayeyarwady River Delta.

Robin presenting her poster

Andrea’s presentation

Conferences are also a wonderful chance to catch up with old friends and make new friends. We hung out with Rip, Dan, and Emily, and heard about their latest research. And, most importantly, we also got a good dose of sunshine after a long PNW winter.

Evan and Rip discussing Astoria Canyon

Hannah’s presentation

Heading to the AGU Fall Meeting

It’s conference season again, and our lab is headed to Washington D.C. to meet and mingle with other scientists and students. Here is what we will be chatting about this time.

First up, our recent research in the Ayeyarwady Delta:

Andrea’s poster: Sedimentary Processes in the Tidal River to Estuarine Reach of the Ayeyarwady Delta (EP13C-2114)

Monday, 13:40 – 18:00 

Walter E Washington Convention Center Hall A-C (Poster Hall)

As the Ayeyarwady River approaches the Andaman Sea, it splits into multiple delta distributary channels, which together discharge >108 t/y of sediment. This study aims to understand: sediment retention and geomorphic variability through the lower distributaries, deltaic growth along mangrove shorelines, and sediment export to the coastal ocean.

Aaron’s Poster: Temporal variability in suspended-sediment dynamics within three distributaries of the Ayeyarwady Delta, Myanmar (EP13C-2113)

Monday, 13:40 – 18:00 

Walter E Washington Convention Center Hall A-C (Poster Hall)

The Ayeyarwady River is one of the largest sources of sediment to the global ocean. However, little is known about the timing, character, or routing of that sediment within the large Ayeyarwady Delta, which is building into the northern Andaman Sea. This study examines how the suspended loads of these distributaries vary spatially (along and between distributaries) and temporally (decennially, seasonally, fortnightly) using in-situ and remote-sensing approaches.

Later that afternoon, our recent research in Brazilian tidal channels:

Robin’s Talk: The Impacts of Channel Connectivity on Tidally-Driven Sediment Transport and Accumulation in a Mangrove Forest (OS14B-03)

Monday, 16:30 – 16:45

Walter E Washington Convention Center – 103AB

Mangrove forests provide many valuable ecosystem services, including wave- and tidal-energy dissipation, sediment accumulation, and substrate stabilization. But, their global extent is rapidly shrinking. Sediment cores and in-situ observations of water and sediment flux were obtained in two tidal channels near the Amazon River mouth to characterize how connectivity impacts tidally-driven sediment transport and accumulation in coastal mangrove forests.

Wrapping up our presentations, our research on the Elwha nearshore:

Hannah’s Talk: Nearshore benthic light attenuation due to sediment transport following dam removal on the Elwha River, WA: In-situ observations and statistical modeling (OS21B-08)

Tuesday, 09:45 – 10:00

Walter E Washington Convention Center – 103AB

The 2011–2014 removal of two dams from the Elwha River, WA provided an opportunity to study the sensitivity of a coastal ecosystem to a large-scale sediment input event. During the dam removal, >10 Mt of sediment was exported to the marine environment. Macroalgae, the primary habitat-forming species in the nearshore, disappeared from the region. Models were created to hindcast to light availability during the dam removal. Benthic light availability was found to be below the threshold for macroalgae growth, supporting the hypothesis that reduced light availability caused the mortality event.

Ocean Networks Canada Workshop: Seafloor collapse and submarine canyons

This month Ocean Networks Canada held a workshop in Victoria, BC focused on the “seabed and sediment in motion” at their observatory sites. They have cabled instruments on the seafloor that continually send data back to shore. The workshop focused on studies at two contrasting focus sites, one on the Fraser River delta, and the other in Barkley Canyon on the continental margin. Submarine canyons are dramatic features of continental margins throughout the world. They can be many kilometers deep and cut far into the shelf, like a Grand Canyon deep underwater. These canyons are hotspots of biological activity as well as conduits for sediment, nutrients, chemicals, and trash. Andrea Ogston attended the workshop to present collaborative research from Barkley Canyon and hear results from colleagues.

Map of a few of the instrumented ONC observatory sites in Barkley Canyon. Our margin off the west coast of the US/Canada is incised by numerous submarine canyons.

On the Fraser Delta, frequent mass failures of the seafloor and energetic gravity flows pose potential problems for the coastal port structures.  Dr. Gwyn Lintern, PGC, showed a dramatic data set from sensors that tumbled in a bottom flow recording velocities of 6-8 m/s, and eventually disconnected and disappeared!  In contrast, Barkley Canyon located off the coast of Vancouver Island has a very limited source of sediment at present, and dynamics are not as dramatic. However, Andrea Ogston showed two modes of particulate transport at ~1000 m water depth within the canyon axis:  1) relatively dense fine particles move down the canyon, carried by residual currents, and are at times pumped back up-canyon by tides, and 2) loose, fluffy phytodetritus (chunks of tiny organisms) from the surface ocean are mixed down into the canyon and during winter downwelling periods can be rapidly transferred to the deep ocean.  This winter process has the potential of adding significantly to the biological pump (which transports carbon to the deep sea). If you’re interested in reading more, check out Thomsen et al., 2017.

After a presentation and discussion of what can be done with the existing data on the Oceans Network Canada observatories, the workshop turned to needs and wants that could enable the next steps in the scientific discovery using the observatory data streams.  New, updated sensors and a reconfiguration of Barkley Canyon’s sensor array will be upcoming and will allow the scientific community to further explore the importance of the wintertime delivery of carbon to the deep sea.  Stay tuned for more on this exciting discovery!

Victoria BC at night during the ONC Seabed and Sediment in Motion Workshop

Sediment Dynamics Group at Ocean Sciences Meeting

Our lab group frequents the biggest oceanography conferences, and the recent Ocean Sciences Meeting was no exception. So, last month our lab headed down to Portland, OR to share our research with the scientific community and to meet up with old and new friends.

Our lab presented on research projects ranging from levee formation in the Amazon tidal river (Aaron Fricke) to sediment dynamics in the Irrawaddy Delta (Chuck Nittrouer) to turbidity from the Elwha dam removal (Hannah Glover) to sediment transport through Amazonian mangrove forests (Robin McLachlan).


Sediment at the UW Undergraduate Research Symposium

Each spring UW hosts the Undergraduate Research Symposium, a showcase of exciting projects from all disciplines on campus. This year, Andrea moderated a session on our favorite topic – sediments! The session “Sedimentary Signatures and Processes: Interpretations from both near and far” included student talks about sedimentology applied to archaeology, agriculture, paleogeology, and oceanography. Julia gave a great presentation of her research about suspended sediments in the Amazon River – from Julia:

“My research visualized the diurnal and seasonal sedimentary behavior along the Amazon Tidal River. Using suspended-sediment concentrations (SSC), I traced the spatial dissipation of the tidal signal along the length of the tidal river as well as the changes in SSC throughout a tidal cycle.

This presentation was a culmination of the irreplaceable years I have spent with the Sediment Dynamics Lab. To conduct research from data I helped collect was incredibly unique and gave me insight into what it takes to pull off such massive projects. I am so grateful to this lab for giving me such valuable experiences as well as unforgettable memories.”

AGU 2014

The 2014 AGU Meeting was a great success! Prior to the official start of AGU, we met with other collaborators researching the Mekong Delta to share information and plan for future field efforts, meetings, and modeling workshops. We plan to have a session dedicated to the Mekong Delta Project at Ocean Sciences 2015 in New Orleans! There will also be a modeling workshop for students held in Vietnam later this year! Many people in our group gave great talks at AGU. Andrea Ogston presented results from our preliminary studies in Vietnam, Emily Eidam presented her work on the Elwha River, and to wrap up AGU, Aaron Fricke gave a talk on his work in the Amazon River. Congratulations to all the speakers!

Salish Sea Conference (May 2014)

On May 1st, Andrea & Emily teamed up to give two presentations on mud dispersal downstream of the Elwha River dam removals at the Salish Sea Conference in Seattle. This conference, which is held every other year, rotates between Vancouver BC, Bellingham, and Seattle. Talks and posters focus on a range of science and cultural topics surrounding the Salish Sea, the waterbody formed by the Strait of Juan de Fuca, Puget Sound, and Strait of Georgia to the north. This year’s conference included a session about the Elwha River restoration, which covered a range of topics from export of reservoir sediment to recovery of salmon species. It was a great opportunity to hear updates and collaborate with fellow researchers.


Ocean Sciences Meeting 2014

The group is well-represented at Ocean Sciences this week, with Andrea co-chairing the session on “Sediment Delivery, Transport, and Deposition in Aquatic Environments,” Dan and Rip giving talks on sediment transport in the Amazon tidal river and Waipaoa shelf (respectively), and Emily presenting a poster on Elwha sediment processes. Go Sed Group!


Dan: Monday, Feb. 24th, 10:30 am, room 312

“Tidal-channel flow and sediment transport in environments influenced by the tidal Amazon River, Brazil”

(Here’s a photo of Dan rocking his talk)

Dan's Ocean Sciences talk


Rip: Tuesday, Feb. 25th, 8:30 am, room 312

“In-situ observations of wave-supported fluid mud on the continental shelf”

(And here’s the question portion of Rip’s awesome talk)

Rip's Ocean Sciences talk


Emily: Tuesday, Feb. 25th, 5 – 6 pm, poster hall (#141, group P)

“Sediment dispersal and deposition on a submarine delta during dam removal: Elwha River, WA”

Short Takes on Dam(n) Science (Feb 2014)

On Tuesday, February 18th at 7 pm, the UW’s Burke Museum will be hosting a series of brief (5 1/2 minute) presentations on Elwha Restoration science at the Neptune Theatre in the University District. The full program is available on the Burke Museum event page; topics include pre-dam archaeology, salmon colonization, fluvial geomorphology, and marine change. Emily will be presenting on sediment transport across the subaqueous delta.

This is offered in conjunction with an ongoing exhibit (Elwha: A River Reborn) at the Burke Museum, which runs through March 9th.

Tickets are $5 at the door.

Should be a fun event!

P.S. Love the UW newsletter photo of Aaron and Wenhua collecting mud! Short Takes Offers the Perfect Nerd-to-Speed Ratio

Short Takes_ELWHA poster_FNL.indd

Elwha Nearshore Consortium Meeting (Feb 2013)

We made it into the Kitsap Sun!  Here is a photo of Emily giving her presentation to the workshop.  Unfortunately, the Sun didn’t spell her name correctly.  Most exciting part Emily presentingof our trip to Port Angeles for the Elwha Nearshore Consortium Workshop was going out on the newly formed sand bar at low tide and walking on unconsolidated former reservoir sediments.  See:  Note that the photo above is courtesy of Roorda Aerial.