Abstract
This work presents the development of low-cost, low-power, and disposable marine monitoring technologies designed to support oceanographic studies in remote and extreme environments. These platforms were initially targeted for underwater volcanic locations but offer a broader application potential for ocean research. Three main technologies were developed and tested: underwater monitoring probes for real-time water quality assessments in geothermal springs, deep-sea probes for vertical ocean profiling and autonomous drift-phase monitoring, and a surface buoy for rapid-response environmental monitoring. Field deployments in diverse locations, including the Ponta da Ferraria (S. Miguel, Azores), Banco D. Joao de Castro (Atlantic Ocean), and the Cumbre Vieja volcanic eruption site (La Palma, Canarias), demonstrated the operational feasibility of these systems. Despite challenges in deep-sea operation and deployment conditions, the results highlight the potential of these platforms for scientific studies, environmental monitoring, and emergency response. Their adaptability and modularity make them valuable tools for a wide range of oceanographic applications beyond their initial focus. Ongoing efforts to improve marine communication reliability, sensor integration, and resilience to extreme ocean conditions hold the potential to further expand the role of these technologies in marine exploration.