Multiparameter sonde data from an autonomous surface vehicle at 4 lakes in Maine and New Hampshire

Data were collected by a catamaran-style autonomous surface vehicle (Catabot), equipped with a multiparameter sonde (YSI EXO2) deployed in bays of four northeastern United States lakes (Lake Auburn, China Lake, Sabattus Pond, and Lake Sunapee) on multiple dates during the months of June-October, 2021. Catabot, first described by Jeong et al. (2020) and Roznere and Jeong et al. (2021), is built upon two inflatable pontoons and an aluminum platform. Catabot moves along the lake surface between 1 m/s (normal operating speed) and 2.5 m/s (maximum speed) (3.6–9.0 km/hr) and has a maximum deployment time for Catabot of 3.5 hrs. Catabot is instrumented with a geographic positioning system (GPS) and compass and communicates with a laptop navigation system and handheld controller via WiFi and telemetry networks. A YSI EXO2 multiparameter sonde (Yellow Springs Instrument Co., Inc., Ohio, USA) was installed on the front of Catabot at a fixed depth of 0.5 m below the water surface with the sensor guard on to collect measurements of temperature, dissolved oxygen, pH, specific conductance, chlorophyll, and turbidity (logged in “rapid” mode in 1 s intervals). Pathways used to direct Catabot were designed prior to deployment using open-source Mission Planner software (Oborne 2019). All predefined paths included both continuous motion at ~1 m/s and occasional 120 s loiter pauses, with loiter-point locations distributed at selected way points along the path. Loiter pause points are flagged in the data. During loiter pauses, when Catabot reached a set loiter-point coordinate, its motors halted until drift from the set point, after which its motors would engage and return Catabot to its loiter coordinate. During all deployments, operators followed alongside Catabot in a kayak or motorized boat to adjust Catabot’s path manually via remote controller in the case of unexpected obstacles.