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The Oceanography Society (TOS) Honors Program provides opportunities for its members to amplify the Society’s values (https://tos.org/about) and to recognize and celebrate the accomplishments of colleagues. However, individual and systemic biases can affect the nomination and selection process. In fall 2021, the TOS Council postponed a cycle of the Honors Program due to lack of diversity in nominees (https://tos.org/tos-news-june-2022). The TOS JEDI Committee (https://tos.org/diversity) is considering ways to generate a large and diverse pool of nominees by embedding TOS’s justice, equity, diversity, and inclusion goals into the honors and awards process. This article highlights some of those suggestions and invites TOS members to weigh in.

The long baseline (LBL) underwater navigation paradigm relies on the conversion of travel times into pseudoranges to trilaterate position. For real-time autonomous underwater vehicle (AUV) operations, this conversion assumes an isovelocity sound speed. For re-navigation, computationally and/or labor-intensive acoustic modeling may be employed to reduce uncertainty. This work demonstrates a real-time ray-based prediction of the effective sound speed along a path from source to receiver. This method was implemented for an AUV-LBL system in the Beaufort Sea in an ice-covered and a double-ducted propagation environment. Given the lack of Global Navigation Satellite Systems (GNSS) data throughout the vehicle's mission, the pseudorange performance is first evaluated on acoustic transmissions between GNSS-linked beacons. The mean real-time absolute range error between beacons is roughly 11 m at distances up to 3 km. A consistent overestimation in the real-time method provides insights for improved eigenray filtering by the number of bounces. An operationally equivalent pipeline is used to reposition the LBL beacons and re-navigate the AUV, using modeled, historical, and locally observed sound speed profiles. The best re-navigation error is 1.84 ± 2.19 m root mean square. The improved performance suggests that this approach extends the single meter accuracy of the deployed GNSS units into the water column.

Abstract-We describe the use of a multi-metal electrochemical cell for measuring ocean pH. The sensor was designed to be robust, inexpensive, and capable of 0.02 sensitivity to pH in the narrow ranges required for marine pH monitoring. A prototype sensor has undergone an extended ocean deployment with promising results.Ocean Sensors; pH Sensors; Metal electrochemistry; Arduino. I. TECHNOLOGY APPROACHThe idea behind the sensor comes from the very low cost unpowered sensors used for soil pH measurements [1]. These simple meters use two metals to generate a potential that is read on an analog meter and are surprisingly accurate at measuring soil pH. We purchased and tested many of these sensors and were very impressed with the accuracy and repeatability of this simple technology. Based on this idea we measured the potential across Zinc and Copper in pH buffered solutions of Instant Ocean. We found that we could calibrate the electrochemical cell to approximately 0.02 pH for the pH 7-9 range. This led to the idea that we could use metals for a useful low cost ocean pH sensor. II. POTENTIAL PROBLEMSBiofouling and corrosion will alter the metal surfaces over time [2], and the metal surface potentials will be sensitive to chemical potentials other than just pH. To overcome this we propose using metal diversity. We are currently using 9 different ¼ inch metal rods in our prototype sensor (Figure 1). These are all mass produced and available at low cost.

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