UC Irvine

Wind disturbances shape forest structure and dynamics, yet direct observations of strong canopy wind gusts remain scarce. We developed a method to detect and characterize strong canopy wind gusts using 24 months (October 2021–September 2023) of high-frequency (1 Hz) meteorological measurements from an old-growth Central Amazon forest. Strong canopy wind gusts were defined as events with speed ≥10 m s⁻¹, representing the upper tail of the wind speed distribution and approaching speeds associated with tree snapping and uprooting in our study region. We identified 424 events, with maximum speeds reaching 17.9 m s⁻¹ and durations up to 90 s. Events occurred on ∼18% of observation days (∼4% of total observation time), with 3.1 ± 2.9 (mean ± standard deviation) events day⁻¹ and 17.2 ± 9.6 month⁻¹. Wind gusts were more frequent during daytime, although their intensity did not differ between day and night. Differences across the topographic gradient emerged at higher wind speeds, with the strongest and longest-lasting events occurring more frequently on elevated plateau. Gusts occurred year-round but were most frequent during the dry-to-wet transition (September–October). Significant relationships between rainfall intensity and gust frequency and duration emerged only during the most intense rainfall events, particularly above the 87th percentile (∼40 mm h⁻¹). However, gusts commonly preceded heavy rainfall by 5–20 min, consistent with convective outflow processes and indicating spatial and temporal decoupling between wind and rainfall. These findings provide high-resolution, site-level insights into canopy wind variability and its links to local atmospheric and environmental conditions in tropical forests.