“Seasonal Changes in Structure and Dynamics in an Urbanized Salt Wedge Estuary” by Maggie McKeon, Alex Horner-Devine, and Sarah Giddings was just published in Estuaries & Coasts. This paper describes hydrographic measurements of a salt-wedge estuary, the Duwamish River Estuary, spanning a 20-fold range in seasonal discharge. The tidal dynamics are well explained by two-layer hydraulic theory, and result in a flood/ebb asymmetry that is modulated seasonally. This is an important result as it suggests that this type of estuary may exhibit a seasonally modulated residual circulation.
“Mechanisms of Mid- to Outer-Shelf Transport of Shoreline-Released Tracers” was just released in the Journal of Physical Oceanography. This paper, led by postdoc Xiaodong Wu, focuses on exchange of a shore-line released tracer from the mid- to outer-shelf. While along-shelf flows are primarily driven by obliquely incident waves, cross-shore flows are are driven by both wind-driven Ekman transport and submesoscale frontal flows. A second paper focusing on the submesoscale fronts is in the works!
“Cross‐Shore Structure of Tidally‐Driven Alongshore Flow over Rough Bathymetry” manuscript published on-line in Journal of Geophysical Research, Oceans! This paper, led by former graduate student Andre Amador, uses autonomous underwater vehicle (AUV) data to examine the cross-shore structure of along-shore flow over a coral reef. Transport of heat, mass, and momentum over the inner-shelf impacts coastal distributions of larvae, nutrients, pollutants, and many other constituents. In this paper, AUV data shows a cross-shore structure of along-shore tidal flow that is well described with a simple momentum balance where friction becomes more important with proximity to shore. The paper further is able to estimate the bottom drag and roughness and show that the flow is dominated by longer wavelength roughness features. This paper combines an impressive array of data through a tidal phase average and compares it to a simple theoretical balance.
16 June 2020. Sarah presented a lightning talk on “Red-tide impacts inside estuaries and on oysters” at the SCCOOS red-tide mini symposium. It was a very interesting event to attend to learn the various parameters leading up to the massive red-tide and the significant biogeochemical and biological impacts. Lots more information can be found at the SCCOOS red-tide bulletin.
05 June 2020. Isa successfully defended her PhD remotely via zoom. All in spite of covid19 restrictions and significant social unrest. Her presentation was excellent and the attendance via zoom was phenomenal – over 100 attendees from around the world – a testament to her impressive scientific accomplishments and extended family and friend support network. She will be continuing to work with Geno and Sarah as a postdoc for a couple months before she moves on to a postdoctoral position elsewhere. Dr. Arzeno truly blossomed into an exceptional researcher during her PhD, leading numerous field campaigns to the Seychelles and tackling a topic well beyond her advisors’ expertise with a variety of tools ranging from Satellite data to numerical model output to analytical models. Congratulations Dr. Isa Arzeno!!!