Early Online Release of new paper in JPO

Our paper highlighting the mismatch between Eulerian and surface drifter statistics in the submesoscale range in the Gulf of Mexico is now available through the Journal of Physical Oceanography. The early online release is available here.

Key Points:

  • Drifters tend to cluster into regions of convergence, such as fronts, windrows, or ‘zipper’ structures.
  • The goal of the paper is to identify if this preferential sampling biases second and third order velocity structure functions.
  • We use simulations from the Regional Ocean Modeling System at 500m resolution and synthetic trajectories found with LTRANS v2b. to make the direct comparison.
  • The results of our work show clear biases at the submesoscale, but agreement with the Eulerian statistics at scales above 10km.
  • Based on the PDF analysis of Choi et al 2017 and our divergence and curl structure functions, we attribute difference between the structure functions to preferential sampling of drifter zones.

 

 

Studying the Ocean from Blackboard to Drones

Abigail Bodner and I taught a 2 weekSummer @ Brown course on introductory oceanography  to 15 high school students from all over the world in late July. The session consisted of lectures, water tank experiments, python coding, a final research project, and a boat tour of Narragansett Bay as well as CTD casts, sediment grabs, a troll, a plankton tow, and drift card releases.  We had a really great time working with the students, and look forward to hearing from them in the future as well as teaching this course again next summer!

Check out our post in the CARTHE Blog as well.

Setting up our Ekman rotating tank experiment.

Looking at pressure with depth.

Mica dust and water show the structures of fine turbulence.

Studying thermohaline circulation.

A CTD cast in Narragensett Bay.

Driftcard release in Narragansett Bay.

One of the final posters presented at the poster session attended by graduate students, postdocs, and faculty from the Department of Earth, Environmental, and Planetary Sciences at Brown University.

 

New Paper Published in Physica D

Our paper presenting a synthesis of mathematical traffic models, observation models, and data assimilation techniques to incorporate Eulerian and Lagrangian traffic flow observations into a macroscopic traffic model is now available. The paper can be found online here.

Key Points:

  • We develop and test methods to incorporate a variety of real-time traffic flow measurements from GPS, traffic sensors, traffic cameras, and cell phone data, etc. to predict macroscopic traffic flow.
  • We show these methods lead to accurate predictions regardless of which data assimilation technique, ensemble Kalman or particle filter, is used.
  • Both techniques allow for parameter estimation of difficult parameters to otherwise prescribe to the traffic models.