Rugged, low-cost, and lightweight rosette water sampler for ocean profiling and mooring deployment

Oceanographers studying climate change, marine ecosystems, and water mass distribution rely heavily on seawater measurements from various depths and locations. A critical tool for obtaining these measurements is the rosette water sampler, which collects and isolates seawater at multiple specified depths for later analysis. However, most commercially available samplers are designed for large sample volumes (>500 mL), requiring heavy-duty lifting equipment typically found only on larger research vessels. This creates unnecessary costs and operational challenges, especially in coastal areas, when large sample volumes are not needed. In response, we present a small, lightweight, and rugged rosette water sampler specifically developed for smaller sample volumes and efficient deployment from small boats without the need for lifting equipment. Weighing 16 kg, the sampler can collect 13 samples of 20 mL each in a single profiling cast, with a maximum depth of 250 m. The instrument has been successfully tested in Northeast Greenland and along the East Greenland coast during three field campaigns between 2021 and 2023. Further development could lead to additional weight reductions and improved ease of use, enhancing its practicality for broader applications.