## 3 Results  
### LE Validation with Flux Tower Observations  
Figure 2 shows scatterplots of the observed LE and estimated LE derived from six LE products at six different sites. One notices that for different sites, the R\({}^{2}\) of the observed LE versus the estimated LE from six products varied from 0.19 to 0.93 at a 99% confidence level, the RMSE varied from 12.6 W/m\({}^{2}\) to 51.4 W/m\({}^{2}\), and the bias varied from \(-\)40.3 W/m\({}^{2}\) to 18.8 W/m\({}^{2}\), with an exception of MODIS LE product. Among them, GLASS LE had the highest R\({}^{2}\) and lowest RMSE in DX1, GT and MY, FLUXCOM LE had the highest R\({}^{2}\) and lowest RMSE in DX2. In contrast, MODIS LE had the lowest R\({}^{2}\) and highest RMSE in DX1, DX2, GT and MY. Moreover, all products underestimated LE in DX1, X2, GT and MY and overestimated LE in YC, except for MODIS. It is clear that MODIS product hada negative bias over six sites compared with observed LE, which indicates that MODIS product systematically underestimated LE in the Haihe River basin.  
Figure 3 shows the scatterplots of the observed LE versus the estimated LE from six products at all sites. For all six sites, GLASS LE had the highest R\({}^{2}\) of 0.58 (\(p<0.01\)) and lowest RMSE of 28.2 W/m\({}^{2}\), followed by FLUXCOM LE with R\({}^{2}\) of 0.54 (\(p<0.01\)) and RMSE of 30.3 W/m\({}^{2}\). In contrast, BESS and MODIS products significant underestimated LE, with a bias of \(-10.7\) W/m\({}^{2}\) and \(-17.6\) W/m\({}^{2}\), respectively.  
Figure 2: Scatterplots of the observed LE and estimated LE derived from six LE products at six different sites.  
Figure 4 presents the Taylor diagrams of six products with observed LE over mixed forests (MF) and croplands (CRO) that cover all six flux tower sites. All LE products except MODIS closed well to the EC observations in MF sites with RMSD values less than 18.0 W/m\({}^{2}\) and R values higher than 0.86, while great differences were found over CRO sites. For individual product, GLASS LE product showed better agreement with EC observations in MF and CRO sites with the lower RMSD values of 13.2 W/m\({}^{2}\) and 23.1 W/m\({}^{2}\), and highest R values of 0.93 and 0.84 respectively, followed by FLUXCOM, PML and GLEAM. In contrast, MODIS LE product had the largest RMSD of 24.1 W/m\({}^{2}\) and 33.8 W/m\({}^{2}\), the lowest R of 0.72 and 0.56 over MF and CRO, respectively. The performance of PML and FLUXCOM LE were similar for two land cover types.  
Figure 5 illustrates the multi-year average seasonal cycles from six LE productions across six sites. Generally, LE derived from all products was comparable in seasonal pattern and magnitude for all sites. GLASS LE product captured LE seasonal variances well across most sites. However, no one product captures the LE variation in summer at HL site. The  
Figure 4: Taylor diagrams for LE observations and LE estimates from six products at both MF and CRO sites.  
Figure 3: Scatterplots of the observed LE versus the estimated LE from six products at all sites.  
seasonal variations curve of MODIS LE and FLUXCOM LE products were similar at DX1, DX2 and MY site. MODIS LE product was lower than observed values at DX1, DX2, MY and YC sites. The observed dual peaks of seasonal LE variation curve at GT site were only captured by GLASS and MODIS LE products. However, MODIS LE product tended to underestimate LE for most sites. Overall, the GLASS LE product has the best performance in the Haihe River basin, followed by FLUXCOM LE product.