## 4 Discussion  
The S2-derived hydroperiod was able to capture wetland flooding dynamics of PPR wetlands in our study area down to 400-800 m\({}^{2}\). Capturing these smaller potholes was achieved by running the segmentation classifications at a 2 m resolution, which captured, pothole shapes better than if it were run at a coarser scale. However, it is likely that closer spacing of the segmentation at larger scales (5 m) can also achieve a similar MMU. It is also possible that an unsupervised pixel-based classification followed by a segmentation could achieve a better MMU. Individual flooded/non-flooded classifications had about 95% overall accuracy which we would expect to be similar across most S2 images, but it would be very difficult to validate all time-series classifications. The hydroperiod results show this area is incredibly dynamic with very few areas actually having permanent open water and many potholes which experienced very infrequent flooding events. Most of the peak flooding images came from spring 2018 which was likely due to the large snowpack that occurred in March and April 2018 [34]. \begin{table}
\begin{tabular}{l c c c c} \hline \hline  & \multicolumn{4}{c}{**Hydroperiod-Based Wetland Inventory**} \\ \hline
**Validation Dataset** & **Wetland** & **Upland** & **Total** & **Producer Accuracy** \\ \hline Wetland & 2945.05 & 920.41 & 3865.46 & 0.76 \\ Upland & 903.71 & 45,225.74 & 46,129.45 & 0.98 \\ Total & 3848.76 & 46,146.15 & & \\ User Accuracy & 0.77 & 0.98 & & OA = 96\% \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Accuracy assessment of the wetland inventory product, summarized at the wetland/upland level, using the same validation data as in Table 3. Numbers are the area of each class in hectares (OA: Overall Accuracy). \begin{table}
\begin{tabular}{l c c c c c c} \hline \hline  & \multicolumn{4}{c}{**Hydroperiod-Based Wetland Inventory**} \\ \hline
**Validation Dataset** & **Marsh** & **Open Water** & **Swamp** & **Upland** & **Total** & **Producer Accuracy** \\ \hline Marsh & 2260.33 & 0.04 & 0.58 & 878 & 3138.95 & 0.72 \\ Shallow Open water & 616.24 & 66.67 & 1.19 & 42.31 & 726.41 & 0.09 \\ Swamp & & & 0.1 & 0.1 & \\ Upland & 903.62 & & 0.09 & 45,225.74 & 46,129.45 & 0.98 \\ Total & 3780.19 & 66.71 & 1.86 & 46,146.15 & & \\ User Accuracy & 0.6 & 1 & 0.98 & & OA = 95\% \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Accuracy assessment of the wetland inventory product. Validation data are from photo-interpretation data by Ducks Unlimited Canada (DUC). Numbers are the area of each class in hectares (OA: Overall Accuracy). The timing of cloud-free S2 images with peak flooding can greatly affect the hydroperoid results. There does appear to be a faint visible seam in the hydroperoid data (Figure 3) which lines up with the boundary between the west and center S2 section orbits. The center orbit appears to have captured peak flooding on 24 April 2018, while the west orbit had images slightly later in the year. For this reason, the center orbit does have a few more temporary wetlands. This is a limitation of the S2 data because cloud-free images during the ideal peak flooding times in spring are not always available. It is not clear if the S2 hydroperiod data captures sub-vegetation flooding dynamics. The binary classifications do classify dark/saturated vegetated wetlands as flooded, but it is likely that SAR coherence products or polarimetric data with longer wavelengths (e.g., L-band) are needed to capture these sub-vegetation/-canopy water dynamics. Fortunately, the vast majority of wetlands in this area are open and, thus, flooding is visible to optical sensors. Overall, S2 hydroperiod accurately and effectively captured water dynamics in the PPR and most limitations are from the availability of cloud-free S2 post snow melt in early spring. Theoretically, SAR data should be ideal for capturing these pothole water dynamics [27; 31; 32]. Similar hydroperiod products could be obtained by thresholding SAR backscatter to capture open water in wetland areas. While [PERSON] et al.