Liu Changjiang, Zhang Fei, Jim Chi-Yung, Oke Saheed Adeyinka, Adam Elhadi
Xinjiang Laboratory of Lake Environment and Resources in Arid Zone, Urumqi, China.
College of Geographic Science and Tourism, Xinjiang Normal University, Urumqi, China.
PLoS One. 2024 Dec 23;19(12):e0315837. doi: 10.1371/journal.pone.0315837. eCollection 2024.
Atmospheric correction plays an important role in satellite monitoring of lake water quality. However, different atmospheric correction algorithms yield significantly different accuracy for inland lake waters beset by shallowness and turbidity. Finding a suitable algorithm for a specific lake is critical for quantitative satellite water-environmental monitoring. This study used Landsat 8 and Sentinel 2 L1 level data of Ebinur Lake in arid northwest China on May 19, 2021. Atmospheric corrections were performed using FLAASH, QUAC, 6S, Acolite-DSF and Acolite-EXP algorithms. The Sentinel 2 reflectance product verified the consistency of the algorithms. Quasi-simultaneously measured hyperspectral data determined the algorithm applicable to Ebinur Lake waters. The results indicate that the Acolite-DSF algorithm has good consistency and high accuracy in the atmospheric correction of Landsat 8 and Sentinel 2 images. Extracting the atmospheric correction of Landsat 8 images found relative error at 0.3 in the Blue, Green, and Red bands and 0.5 in the NIR band. For comparison, the relative errors of Sentinel 2 in all bands are 0.3. Therefore, these four bands of Landsat 8 and Sentinel 2 data are recommended for temporal monitoring of water-environmental parameters in Ebinur Lake. Besides identifying the suitable atmospheric correction algorithm for Ebinur Lake, this study analyzed the atmospheric correction errors of common wavebands for remote sensing monitoring of water bodies, especially applicable for inland salt lakes of arid regions.
大气校正在湖泊水质卫星监测中起着重要作用。然而，对于受浅水和浑浊困扰的内陆湖泊水体，不同的大气校正算法产生的精度差异显著。为特定湖泊找到合适的算法对于定量卫星水环境监测至关重要。本研究使用了2021年5月19日中国西北干旱地区艾比湖的Landsat 8和Sentinel 2 L1级数据。使用FLAASH、QUAC、6S、Acolite-DSF和Acolite-EXP算法进行大气校正。Sentinel 2反射率产品验证了算法的一致性。准同步测量的高光谱数据确定了适用于艾比湖水体的算法。结果表明，Acolite-DSF算法在Landsat 8和Sentinel 2图像的大气校正中具有良好的一致性和高精度。提取Landsat 8图像的大气校正发现，蓝、绿和红波段的相对误差为0.3，近红外波段为0.5。相比之下，Sentinel 2所有波段的相对误差均为0.3。因此，建议使用Landsat 8和Sentinel 2数据的这四个波段对艾比湖的水环境参数进行时间监测。除了确定适用于艾比湖的大气校正算法外，本研究还分析了水体遥感监测常用波段的大气校正误差，特别适用于干旱地区的内陆盐湖。
