“…Continuous-wave (CW) Doppler lidar can remotely obtain accurate three-dimensional flow observations without disturbing the flow. Consequently, CW lidars are extensively applied to detect wind profiles (Köpp et al, 1984;Peña et al, 2009), assess wind resources (Bingöl et al, 2009;Viselli et al, 2019), test wind turbine performance based on wake measurements (Wagner et al, 2014;Shin and Ko, 2019;Fan et al, 2023), predict the incoming gusts and flow to reduce loads (Bos et al, 2016), and study turbulence around a suspension bridge (Cheynet et al, 2016) and in the near-wake region of a tree (Angelou et al, 2022), with good spatial and temporal resolutions. Recently, two CW lidars were used to measure the two-dimensional downwash wind fields in a horizontal and a vertical plane below a hovering search-andrescue helicopter (Sjöholm et al, 2014).…”