# Monitoring Small Water Bodies Using High Spatial and Temporal Resolution Analysis Ready Datasets
## 4 Discussion
The Planet Fusion algorithm combines data from multiple satellites to establish a baseline of OFR surface area time series by filling gaps with synthetic pixels. Nonetheless, the smoothing effect should be interpreted cautiously, as some changes in the time series due to large rainfall events or frequent irrigation activities may be smoothed out. This is especially relevant for the periods of the year when there are more synthetic observations (Figure 4) and the uncertainties in surface area tend to be higher (Figure 5). Additionally, because Planet Fusion is based on a robust algorithm that uses data from various satellites, this dataset requires more image processing steps and higher computing power when compared to Basemap, which is generated at a faster speed with lower processing costs. Meanwhile, the Basemap time series may contain a \"stair-step\" effect caused by repeated observations when the Basemap scene composition was kept constant due to a lack of new cloud-free scenes (e.g., Figure 8, OFR D, early March 2021). By keeping the same image composition, the Basemap algorithm avoids generating synthetic pixel values while still providing a cloud-free observation. Nonetheless, it is important to keep in mind that there could be scenarios (e.g., when there is a lack of a new cloud-free scene for weeks or more) in which the Basemap may have the same number of observations as PlanetScope, hence decreasing its monitoring capabilities. Our findings have important implications to future hydrological studies that aim to monitor small water bodies at large scale and high temporal frequency. For the OFRs in eastern Arkansas, the Basemap and Planet Fusion surface area time series helped unravel sub-weekly changes in OFR surface area, as well as yearly seasonality (Figure 8). OFRs surface area changes are pivotal information for calculation of OFR water volume inflows and outflows. This can be achieved by combining the surface area time series with the area-volume equations (e.g., hyposometry), which are derived using the OFRs' geometric shape and depth [56; 61; 62]. Estimating OFRs volume change helps bridge one of the key limitations when modeling the cumulative impacts of OFRs on surface -hydroology, as OFR water volume change is commonly assumed to be equal to all OFRs located in a watershed [24; 25; 63]. In addition, as the number of OFRs is projected to increase globally [24; 27], understanding the impact of OFRs on surface hydrology is pivotal when seeking indicators to determine the optimal spatial distribution and number of OFRs, as well as their storage capacities and water management plans aiming to mitigate downstream impacts. Beyond implications to hydrological studies, we demonstrated that Basemap and Planet Fusion can be used to monitor surface area changes for a network of OFRs (Figure 8). This information can be used by regulatory agencies to create water status reports to improve regional water management and water use efficiency. These reports would be especially relevant during the dry critical period of the year when farmers are frequently irrigating.