MISOBOB Notes from the field, July 2019

Notes from the field on the R/V Sally Ride by Chief Scientist Emily Shroyer (OSU) with MOD-PIs (MacKinnon, Lucas) as part of the ONR-funded MISO-BOB experiment.

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July 23, 2019:

Greetings from 16°N 89°E...

Over the last week we have been filling in our map with a ship-based survey, working in the general vicinity of gliders and drifting buoys. Our survey has been oriented across curving AVISO SSH contours associated with a strong eddy to our southwest (see map and WW-buoy time series figs, below). The SVPB drifters that we deployed early in the cruise have fully populated our sampling region. We have been lucky to find ourselves in a region of convergence with strong near-surface fronts. It appears this also a region of biological activity with 10(!) sea turtle sightings and elevated near-surface chlorophyll and backscatter from the FastCTD, all of which lines up well with satellite ocean color images. The general sense is of a productive coastal upwelling jet ejected into the central Bay by the energetic mesoscale. We have collected some beautiful cross-front sections detailing this jet's rapid and complex evolution, as well as several realizations of the ocean’s response to atmospheric cold pools.

The winds have been picking up over the last two days, but we had a few very calm/quiet days over the weekend. There have been a few scattered rain events, typically in the afternoon, but overall the conditions have been clear and sunny. We even had a beautiful view of the recent lunar eclipse (photo courtesy San). Over the next few days we are planning on intensive sampling around buoys 2 and 3. The forecast indicates an increased likelihood of convective activity, but a well-organized miso event that started propagating into the Bay will likely decline before reaching our area.

Emily with Drew, Jen, Tom, Jonathan and Simon

July 14, 2019:

We have set up on the western side of international waters in a strong eastward flow. The three WHOI-Wirewalker buoys have been out for a few days now. One turbulence glider and one Seaglider have also been deployed in the region while two Spray gliders slowly make their way north. Thirty of the thirty-five drifters are also in the water. We are running a long survey line with the ship on the upstream side of the buoy array. We have been transiting through a region of upper ocean variability (MLD, T/S. Fluorescence) that we think may be related to an offshore filament of upwelled coastal water (based on HYCOM). You can see our general set up in the figure below (courtesy Tom) that shows Aviso SSH and currents, the buoy tracks over the last two days, and the ship track over the last day.

Emily with Drew, Jen, Tom, Jonathan and Simon

Updating the Revelle’s novel velocity measuring system

The MOD group has long specialized in Doppler sonar techniques, pioneered over 30 years ago by Rob Pinkel and Jerry Smith.  For about 20 years, Scripps’ flagship the R/V Roger Revelle has carried a one-of-a-kind such system, the Hydrographic Doppler Sonar System (HDSS).  Unlike conventional Acoustic Doppler Current Profilers carried on most ships, the HDSS has much higher power and much narrower beams, allowing greater precision, finer resolution in the vertical and greater range.  While the Revelle is in dry dock for her midlife refit, our group is taking the opportunity to remove the HDSS from her hull, modernize it and reinstall it.

Many long hours have been spent underneath the Revelle.

It is a massive job and we have now successfully removed the old system, which requires hard work and long hours beneath the enormous ship.  Creating the new system, which will have still higher power and will eventually allow better removal of the ship’s rolling and tilting from the measured signals, has involved long hours by the Marine Physical Laboratory machine shop and painstaking work repotting the transducers and cabling them. The final installation will take place in August.

Wish us luck!

Jennifer MacKinnon championing equity at Scripps

Professor Jennifer MacKinnon, third from right, was acknowledged for her work in cultivating belonging among early career scientists at Scripps Institution of Oceanography. Photo by Wesley Ruan

The MOD team’s own Jennifer MacKinnon has been appointed the new Associate Dean of the School of Marine Science for Faculty Equity. In addition, she was recently honoured at the UCSD annual Inclusive Excellence Award along with 13 other individuals at UCSD recognized for their outstanding efforts to celebrate cultural differences and promote fairness across campus. Read more here. 

Associate Dean for Faculty Equity is a new academic position at Scripps created with commitment to the UC San Diego Principles of Community, in particular to equitable practices for recruitment, retention and evaluation of faculty. The title is given to the SIO Faculty Equity Advisor (FEA), with hopes of enhancing the ability to recruit and retain excellent faculty and evaluate them in a fair way by having a ladder-rank faculty member specifically tasked with equity concerns in regards to these activities.

The new Associate Dean is not alone in the quest for fairness but will collaborate with the SIO coordinator for Equity, Diversity and Inclusion (EDI) initiatives, and will be backed up by an Alternate FEA that will step in whenever the ocean calls the Associate Dean away on field work.

Professor MacKinnon is currently the Primary FEA, and her position as Associate Dean for Faculty Equity extends until June 2021, but is eligible for renewal.

Way to go Jen!

Hydrographic Doppler Sonar System (HDSS) upgrade

The Hydrographic Doppler Sonar System (HDSS), is now 20 years old and is getting upgraded when R/V Revelle undergoes her midlife refit this summer and fall.  HDSS is a state-of-the-art system for measuring ocean currents.  We are substantially upgrading and improving the old system, with enhancements including greater power and real-time beam forming that corrects for the roll and pitch of the ship, improving precision by keeping the beams much more constant orientation.

Engineers Sara Goheen and Mike Goldin and Professor Rob Pinkel ultrasonically clean a cable from the old system in preparation for the installation this summer and fall.

Look out Fast CTD!

The Fast CTD encounters ice for the first time.  

Arctic Aloha

We've spent the last few days in Nome, Alaska, loading the R/V Sikuliaq and preparing to set sail. We have been gifted with unusually warm sunny weather, and are celebrating with Aloha Friday.  We set sail tomorrow morning for points further north, wish us luck!

Photo: Members of the MOD group Jen MacKinnon, Giulio Meille, honorary member Ben Barton (Bangor U.), Effie Fine, Jonny Ladner, Sara Goheen, Nicole Couto, San Nguyen, and Mike Goldin. 

Ready.....set....

8 members of the MOD group are gearing up to head to Nome, Alaska next week,  with a dozen colleagues from other universities, to embark on a month-long expedition to study the Arctic Ocean.  The project is an Office of Naval Research funded experiment entitled the "Stratified Ocean Dynamics of the Arctic (SODA)". One of the main goals is to understand what processes set the amount and distribution of heat in the Arctic ocean, and how that accumulated ocean heat might or might not be responsible for the observed accelerating rate of Arctic sea ice loss.  We'll add a series of posts once we get underway with more details of the science, instruments, people, and maybe even a polar bear sighting!  Bu to start us off, here's an image from the the National Snow and Ice Data Center (http://nsidc.org/arcticseaicenews/).  It's a map of the Arctic Ocean as would be seen from above (satellite).  The white area is where there is currently sea ice as of today, August 24th.  The orange line is where the sea ice extent used to be, on average.  There's a lot less now, which has significant implications for not only the Arctic ecosystem and the human population surrounding it, but the global climate as well.  We are hoping that some of the secrets we uncover will help us not only understand what's happening now, but more accurately predict how this will play out as the earth continues to warm.  Stay tuned!  

The Epsilometer and the biological hotspots ...

In April 2018, a team of Scripps graduate students designed a 3 days experiment on the R/V Sproul in order to explore a biological hotspot south of San Clemente Island, only a few miles west of San Diego. This area is known to support large populations of demersal and pelagic fish, such as rockfish and tuna. While both the scientific and local fisheries communities are well aware of such biological productivity, little is known about the physical mechanisms that aid the high productivity at this site. The students proposed to investigate the flow in order to test several hypotheses and determine the physical mechanism that drives the elevated biological productivity.

In addition to the Del Mar mooring recovery and deployment of a WireWalker, the students tested new sensors developed by Scripps physical oceanographers Matthew Alford and Arnaud Le Boyer. Dubbed the epsilometer or “epsi,” the device uses advances in electronics borrowed from the cell phone industry to measure water turbulence (epsilon) in a low-cost, low-power manner. 🎥: Isabela Le Bras

Iceland cruise: survived

Team MOD successfully deployed two wire walkers, the fast CTD and two epsi-fish microstructure profilers in challenging conditions (up to 50 knot winds and 8-m seas) on R/V Armstrong.

We learned much about the generation of internal waves and the modulation of mixed-layer turbulence by the wind - and the effects of the wind on the ship and its scientists!

MOD PIs chair first-ever Gordon conference on Ocean Mixing

Last week, the very first Gordon conference on ocean mixing took place in Andover, NH.  167 participants from all over the world learned about the state of the art of our field and its impact on other fields.  It was enlightening, inspiring and a lot of fun!