# Inland Water Level Monitoring from Satellite Observations:
## 3 Review Results
### Satellite Missions for Inland Water Level Monitoring
#### 3.1.3 Other Satellite Missions
\begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Publication** & **Satellite** & **Data** & **Validation** & **Accuracy Metrics** \\ \hline \multirow{4}{*}{[97]} & \multirow{4}{*}{ICESat, ICESat-2} & L2-GLAH14 (ICESat), & & ICESat: R = 0.85, RMSE = 0.15 m, \\  & & L2-GLAH14 (ICESat), & & MAE = 0.1 m, MAD: 0.05–0.25 m, \\  & & ATL13 products V005 & & \(\sigma\): 0.078–0.37 m and for ICESat-2: \\  & & (ICESat-2) & & R = 0.69, RMSE = 0.05 m, \\  & & & MAE = 0.06 m, & MAD = 0.03–0.05 m, \(\sigma\) = 0.04–0.07 m \\ \hline \multirow{2}{*}{[95]} & ICESat-2 & ATL13 products & In situ gauge & R\({}^{2}\) = 0.28–0.99, RMSE = 0.4–1 m \\ \hline \multirow{4}{*}{[102]} & \multirow{4}{*}{GEDI, ICESat-2} & ATL13–V004 (ICESat-2), & & ICESat-2: R = 0.96–0.99, \\  & & L2A (GEDI) & & MAE = 0.03–0.1, RMSE = 0.04–0.13 m \\  & & & L2A (GEDI) & & and GEDI: R = 0.56–0.95, \\  & & & MAE = 0.31–0.38, RMSE = 0.35–0.46 m \\ \hline \multirow{4}{*}{[99]} & \multirow{4}{*}{ICESat, ICESat-2, GEDI} & \multirow{4}{*}{GLA14, ATL13–V003, & & ICESat-2: RMSE = 0.06–0.12 m, \\  & & & biases = \(-\)0.08 \(\pm\) 0.07 m, ICESat: \\  & & & RMSE = 0.10–0.25 m, \\  & & & L2B & RMSE = 0.18 \(\pm\) 0.16 m, GEDI: \\  & & & biases = \(-\)0.18 \(\pm\) 0.16 m, GEDI: \\  & & & RMSE = 0.28–0.40 m, \\  & & & biases = \(-\)0.24 \(\pm\) 0.24 m \\ \hline \multirow{2}{*}{[71]} & ICESat-2 & ATL13 & In situ gauge & RMSE = 0.05–0.14 m, R = 0.74–0.95 \\ \cline{2-6}  & & ATL13 & In situ gauge & RMSE = 0.24 m, bias = \(-\)0.11 m, \\  & & & MSD = 0.04 \\ \hline \multirow{2}{*}{[101]} & ICESat-2, GEDI & ATL13–V004 (ICESat-2), & & In situ gauge, DAHITI, & ICESat-2: std = 0.03 m, GEDI: \\  & & L2A (GEDI) & and Hydroweb & std = 0.11 m, Combining two \\  & & & and missions: R \(>\) 0.8 \\ \hline \multirow{2}{*}{[96]} & ICESat-2 & ATL13–V003 & In situ gauge & RMSE = 0.32 m, R \(>\) 0.99 \\ \cline{2-6}  & & & & \\ \hline \multirow{2}{*}{[103]} & GEDI & L1B and L2A & In situ gauge & ubRMSE = 0.27–0.43 m, R = 0.34–0.66, \\  & & & bias = 0.35–0.54 m \\ \hline \hline \end{tabular}
\end{table} 
Table 3: _Cont._can be used to monitor water level changes with relatively high temporal resolution, providing estimates every three to twelve days, as well as to monitor water bodies that are not directly located at the satellite's nadir and water bodies substantially smaller in area [110]. Furthermore, inland water levels were estimated by Interferometric Imaging Radar Altimeter (InIRA) carried out by the Tiangong-2 mission. The water levels obtained by InIRA are compared with surface levels derived by CryoSat-2 InSAR data showing that InIRA data is more stable and level estimates can be obtained with higher precision using the further processing InIRA data [111]. However, CryoSat-2 can measure the larger inland water levels with higher accuracy due to more observations, while InIRA obtains more observations in smaller lakes due to its three-dimensional imaging capability. Additionally, a comprehensive evaluation of inland water levels based on satellite gravimetry indicates that GRACE, and specifically its derived index GRACE-DSI can obtain water level estimates with RMSE values ranging from 0.88 to 1.12 m compared to gauge water levels [105]. Water level measurements results based on GRACE are superior to those reconstructed from traditional remote sensing indices, such as Palmer's Drought Severity Index (PDSI), and El Nino Southern Oscillation (ENSO) indices. GRACE is widely used to infer large-scale terrestrial water storage variations [112; 113]. Finally, an approach based on the differences between daytime and nighttime land surface temperatures (LST) observations of Moderate Resolution Imaging Spectroradiometer (MODIS) shows a strong relationship both with in-situ and with Jason-2 water levels [114]. The LST difference from the thermal infrared (TIR) measurements of MODIS is shown to have the potential to produce high temporal resolution water levels.