Probability of SO₂ appearance as a function of local time, using the whole 2012–2022 dataset (black points). The error bar is proportional to n^−0.5, where n is the number of observations for which the local time is observed. Red points: dataset without the 2020–2021 data, as shown in Fig. 14 of E20. The local hour scale increases from right to left, corresponding to the orientation on the Venus disk as seen by an external observer.