“…The 2-D speed of NCL increases from 2.2 × 10 5 to 12.8 × 10 5 m/s (by a factor of 5.8), with an average of 7.3 × 10 5 m/s, and the 3-D speed of NCL increases from 2.2 × 10 5 to 15.3 × 10 5 m/s (by a factor of 7.0), with an average of 8.5 × 10 5 m/s (see Figure S4 in Supporting Information S1). That is consistent with previous reports on UCLs initiated from tall objects with its speed being increased with time (e.g., et al, 2014;Lu et al, 2013Lu et al, , 2015Qi et al, 2021), while it is contrary to UCLs observed on common buildings with the speed being approximately constant (e.g., Saba et al, 2017Saba et al, , 2022Saba et al, , 2023.…”