TENDER: A Conceptual Tethered-Probe System for Localized Remediation of Coastal Acidification Events

Shresth Katiyar (1), Ishita Kothawade (2), Akshath Suda (3), Akash Bhattacharya (4), Neev Shah (5), Joshua Amaladass (6), Alex Colin (6)

(1) American High School, (2) Mission San Jose High School, (3) Dougherty Valley High School, (4) Basis Independent, (5) Stratford School, (6) Robolabs

Abstract—Ocean acidification is usually framed as a global average, but that is not where it is first felt. In confined coastal waters, local processes like upwelling and organic-load respiration can depress pH faster and further than the atmospheric signal alone, making the confined water body, not the open ocean, the natural unit for detection and response. Existing interventions do not meet that scale: hatchery buffering is fixed to a pipe, cultivated macrophytes are rooted in place and reversed at night, and alkalinity trials broadcast from a ship, where dilution is the goal. None delivers a metered, sensor-triggered dose inside a confined water body and then stays in place to verify whether the chemistry recovers. This paper presents TENDER (Tethered Environmental Neutralization and Dispersal for Ecological Restoration), a system proposed for that gap. A support vessel would carry the operator station and cultivation facility, a carrier vehicle would transport a fleet of tethered probes, and each probe would sense the local chemistry and deliver a metered dose of buffered sodium carbonate or a biological payload under operator authorization, with a monitoring node left behind to report on recovery. Its distinguishing contribution is a cultivation loop, in which organisms native to the treated site are sampled, cultured, and returned rather than shipped in, an approach supported at microcosm and mesocosm scale but not yet at field scale. TENDER is presented as a conceptual design, developed to the point where its architecture, operating logic, and limits can be examined and built upon. If developed as intended, it could correct the chemistry of a localized acidification event while supporting the organisms already capable of clearing the load that drives it.

Full Article: Katiyar, S., et al.

Keywords: Coastal Acidification, Marine Robotics, Tethered Underwater Vehicles, Alkalinity Buffering, Bioremediation, Biostimulation, Autochthonous Bioaugmentation, Shellfish Aquaculture