Against the backdrop of growing global attention to climate change and marine environmental protection, marine carbon flux monitoring has become an increasingly critical approach for understanding and assessing the role of marine ecosystems in the global carbon cycle.

During its participation in the Guangdong Provincial Marine Economy Development Special Fund project, HydrovoX, in collaboration with the South China Sea Institute of Planning and Environmental Research of the State Oceanic Administration and Xiamen University, actively explored and implemented the design and application of a mobile marine carbon flux intelligent monitoring system.

The Unmanned Surface Vehicle platform is equipped with key carbon flux sensing instruments, including a meteorological station, multiparameter water quality sensors, and a CO₂ gas analyzer, enabling real-time acquisition of sea surface partial pressure of CO₂, marine environmental parameters, and atmospheric meteorological data. These data are transmitted back to the shore-based control system via BeiDou and TianTong satellite communication links, where they are processed and used to calculate marine carbon flux in real time.

During monitoring missions, the Unmanned Surface Vehicle can be remotely configured to operate in a virtual anchoring mode for fixed-point observation of carbon flux variations in a target sea area, or in a multi-point route navigation mode to survey carbon flux changes across broader regions.

A field demonstration of the mobile intelligent monitoring system based on the Unmanned Surface Vehicle platform is shown in the figure below.

Figure: Sea Trial Site

The Unmanned Surface Vehicle is powered by the vertical motion of ocean waves and utilizes unpowered wing plates to generate forward propulsion. It features clean and green operation, as well as long-endurance capability (theoretically unlimited range). Compared with traditional observation platforms, it offers significant advantages in large-scale, long-duration, and low-cost marine monitoring.

Its main advantages are as follows:

1. Sustainability and long-term operation:
   The Unmanned Surface Vehicle can operate autonomously at sea for extended periods without human intervention, enabling long-term and continuous marine carbon flux observations. Compared with traditional ship-based or buoy-based methods, it provides much longer data acquisition duration. 
2. Wide spatial coverage:
   It is capable of large-area marine surveys without being constrained by ship routes or fixed observation stations, providing broader spatial coverage for global carbon flux research. 
3. Cost efficiency:
   Compared with conventional marine observation methods, the Unmanned Surface Vehicle offers significant advantages in operational and maintenance costs. It requires no fuel and is primarily powered by wave energy and solar energy, greatly reducing long-term monitoring expenses. 
4. Multi-functionality:
   The platform can carry multiple types of sensors. In addition to carbon flux monitoring, it can simultaneously measure various ocean parameters such as water temperature, salinity, and current velocity, providing multidimensional datasets for comprehensive marine environmental studies. 
5. Strong adaptability:
   The Unmanned Surface Vehicle can operate reliably in various marine environments and maintain stable performance even under harsh weather conditions, ensuring continuous and reliable data collection. 
6. Real-time and secure data transmission:
   Equipped with BeiDou and TianTong satellite communication systems, the platform enables real-time and secure data transmission, allowing researchers to access and analyze data promptly and improving research timeliness. 
7. Green and environmentally friendly:
   The Unmanned Surface Vehicle has minimal environmental impact. Its operation produces no pollution and generates low noise, making it suitable for deployment in ecologically sensitive marine areas. 

In summary, the application of Unmanned Surface Vehicles in marine carbon flux monitoring not only improves observation efficiency and reduces costs, but also provides strong technical support for a deeper understanding of the marine carbon cycle and its impact on global climate change.