Next-generation Irwin Sensors for characterizing surface shear velocity

TitleNext-generation Irwin Sensors for characterizing surface shear velocity
Publication TypeConference Paper
Year of Publication2023
AuthorsWebb, NP, Ziegler, NP, Brown, E, Nikolich, G, Gillies, JA, Edwards, BL, Patel, S, Van Zee, JW, Trautz, A, LeGrand, SL
Conference NameInternational Conference on Aeolian Research
Conference LocationLas Cruces, N.M. USA

Quantifying the spatial and temporal variability of surface shear velocity (us*) is needed to better understand the timing and patterns of sediment flux and dust emission. Previous field and wind tunnel studies have used the Irwin sensor (Irwin 1981), an instrument measuring the surface pressure differential, to monitor in situ us* (King et al., 2005; Gillies et al., 2006; Ziegler et al., 2023). Sensor designs have proven encumbering to maintain long-term because of their sensitivity to moisture and susceptibility to becoming clogged with particles. Additionally, they require cables to connect to a local base station, which presents its own set of challenges related to site preparation. Here we present a new generation of Irwin sensors, taking a first step to address the aforementioned issues. The new generation sensors utilize modern manufacturing techniques and up-to-date electronics to minimize installation footprint and site impact by enabling local processing, storage, and wireless transmission of sensor data. This new sensor can wirelessly transmit data over 27 m to a base station, or further, using mesh network communications in which each sensor acts as a mesh node, operating for up to eight days without recharge. The sensors are housed in custom-made plastic “sleeves” that enable rapid deployment and retrieval, e.g., with forecasted rain events. Currently deployed at the National Wind Erosion Research Network site at the USDA Jornada Experimental Range in Las Cruces, NM, the sensors are being used to characterize us* along the sides of roughness elements.