OpenCTD sensor template

Conductivity, temperature, and depth (CTD). These three measurements allow scientists to unlock ocean patterns hidden beneath the sea's surface. The ocean is not uniform, it its filled with swirling eddies, temperature boundaries, layers of high and low salinity, changing densities, and other physical characteristics invisible to an observer floating upon its surface. To reveal these patterns oceanographers employ a CTD--an oceanographic instrument that, at its core, measures temperature, salinity, and depth down a water column. The CTD is the workhorse of oceanographic research.

CTDs are expensive, and that expense can act as a barrier-to-entry for researchers with limited budgets, scientists from developing nations, citizen oceanographers, and students of all levels interested in learning more about their local coasts and waterways.

The OpenCTD is a low-cost, open-source CTD suitable for both educators and scientists. The platform is built using reasonably accessible parts and