AUEs in the news

Today the Autonomous Underwater Explorer project was featured in an article in the Scripps News and also a press release from the National Science Foundation. From the press release:

In an effort to plug gaps in knowledge about key ocean processes, the National Science Foundation (NSF)’s division of ocean sciences has awarded nearly $1 million to scientists at the Scripps Institution of Oceanography in La Jolla, Calif. The Scripps marine scientists will develop a new breed of ocean-probing instruments. Jules Jaffe and Peter Franks will spearhead an effort to design and deploy autonomous underwater explorers, or AUEs. AUEs will trace the fine details of oceanographic processes vital to tiny marine inhabitants.

 

Links:

MAZOOPS first deployment at sea

We returned yesterday from the first deployment of the new MAZOOPS zooplankton sonar at sea. We were able to deploy the system several times per day, and collected nearly 100 GB of acoustic and image data from two different stations off the coast of San Diego.  Deployments of the MAZOOPS were combined with MOCNESS tows and the two modalities generally showed good agreement.

In total, the system was deployed eleven times during the four day cruise. Typically, the system was deployed running in autonomous mode during the day down to 250 meters, and running in tethered mode with real-time data during the night down to 100 meters.

During the daytime, typical profiles showed that most of the acoustic scattering was down around 250 meters or deeper. These data were supported by images from the low-light-level camera on the MAZOOPS. Image data showed that copepods and euphaussiids were likely the most abundant animals, and these data were confirmed by the MOCNESS tows.

On two occasions, while idling at 30 meters depth, the system encountered very high concentrations of euphausiids which were seen in acoustic data as a dramatic increase in the number of echoes and also the amplitude of these echoes. Image data showed a proportional increase in the number of animals imaged. These small scale features are unlikely to be seen in MOCNESS data (due to its averaging of animal concentrations over much larger scales than the MAZOOPS.

One of the key features of MAZOOPS is the combination of acoustic and optical imaging sensors that image the same field of view, making the system truly multimodal. By combining these data together more information about the type of animal and its orientation are available to aid in understanding acoustic echoes. The multiview nature of the acoustic system can then be used in concert with optical imagery to obtain improved estimates of shape and/or taxa specific abundance.

A big thanks to Jules, Fernando, Florian, Prasanna, Justin, Christian, Gabriel, Paul, the crew of the R/V Sproul, and all of the other team members who made this cruise possible.

Below are a few images from the cruise:

FAD sonar returns from one month on FLIP

December 4, 2007 – The FAD Sonar just returned from a month long deployment on board of the R/P Flip. It was used as a supplemental instrument to measure fish and plankton aggregating around Flip during the FLIP07 SCORE experiment conducted by John Hildebrand and Elizabeth Henderson. We’d like to thank Liz for an outstanding job of running the system throughout the 30 day deployment and recording 30 Gigabytes of data that we can’t wait to analyze!

Jaffe Lab featured on Pulse of the Planet

This week we are being featured on an internationally syndicated radio show: Pulse of the Planet. The audio describes our work in testing a new idea related to measuring the microbial environment and hence the viscosity of the ocean. If you would like to listen, please go to the following link and check out the archives from August 14, 15, and 20th and October 9th.
Webpage: http://www.pulseplanet.com
http://www.pulseplanet.com/sphider/search.php?query=Jaffe&search=1

Return from Dabob Bay

We just returned from our spring cruise to Dabob Bay in the state of Washington. The purpose of our cruise was to explore a hypothesis that has to do with the foraging behavior of zooplankton, the small (1-4 mm) animals that live in the sea. Every night they make a big trip to the surface waters from the deeper parts of the ocean to forage on plants (phytoplankton). Once there, do they eat, turn around, go back down? or: Do they eat and keep eating up in the surface waters? Our new imaging system is a bispectral (two wavelength) method which records not only the green reflected light from their outsides (carapace) but also their insides (the phytoplankton) that they ate that fluoresces in the red. Together, the green reflected light and the red light from their insides tells us which animals they are and how recently they ate. We spent about 8 days on the U. of Washington ship the Tommy Thompson in Dabob Bay and worked almost all night to see these little guys make a living. We returned, tired but happy with lots of great data that will help us try and unravel how these animals, probably the most numerous multicellular animal on the planet, make a living.

Unique data set collected during Recent FIDO cruise

The goal of our most recent cruise was to deploy our FIDO vehicle in various configurations to observe particle size spectra and also time varying scatter of light in the ocean.  Leaving from San Diego we over-nighted off Catalina (up and back) on the way to the Channel Islands. The cruise went extremely well.  We profiled with the FIDO – PHI configuration for 4 nights and then switched over to observe time varying scatter by suspending a small disk from FIDO with the laser incident on it from one direction and the camera imaging from the other.  We saw some amazing radial spokes of light emanating from the center of the scattered light patterns that we believe have never been seen before!!….What could they be from?  We are currently figuring out what we got, what to do with it and what it will tell us about oceanic micro structure and the propagation of light the ocean.  Stay tuned for more.