Development of In situ Nitric Oxide Sensor

Objective

Nitric oxide (NO) is a critical yet understudied component of the marine nitrogen cycle and atmospheric chemistry, with its concentration, dynamics, and sources in the ocean poorly constrained due to limitations in current measurement methods. Existing techniques often underestimate in situ NO concentrations and fail to capture short-lived events, diurnal cycles, and fine-scale spatial heterogeneity, as NO's high reactivity and short lifetime lead to rapid degradation/loss during sampling. The DINOS project addresses these challenges by developing the first reliable, user-friendly underwater sensor for dissolved NO, offering picomolar (pM) sensitivity and second-scale response. By advancing in situ sensor technology, DINOS minimizes sample loss and handling artifacts, building on the success of WHOI’s ROS instruments (DISCO and SOLARIS). This innovation enables the capture of transient biogeochemical processes, enhancing our understanding of NO’s complex dynamics in marine systems. During the 24-month outgoing phase at Woods Hole Oceanographic Institution (WHOI), the sensor will be developed in collaboration with Dr. Scott Wankel and Dr. Colleen Hansel, leveraging their expertise in ocean sensor design and engineering. The prototype will undergo laboratory testing and calibration at WHOI, followed by field validation. In the 12-month return phase, the sensor will be deployed at the Boknis Eck Time Series Station in Eckernförde Bay (southwestern Baltic Sea), coordinated by Prof. Dr. Hermann Bange at GEOMAR. These advancements will provide unprecedented insights into the role of NO in marine biogeochemical cycles.