使用表面能量平衡模型和中分辨率卫星数据进行蒸发透气估计:用于持续监测的操作方法
1Department of Land and Water Management, IHE Delft Institute for Water Education, 2611 AX, Delft, The Netherlands. s.pareeth@un-ihe.org.
Scientific reports
|July 25, 2023
概括
这项研究开发了一种方法来填补卫星数据的空白,用于监测农业用水情况. 该方法准确地重建了每月的实际蒸发透气 (ETa) 动态,这对水安全至关重要.
科学领域:
- 水文和远程传感技术
- 农业用水管理农业用水管理
- 地理空间分析是什么
背景情况:
- 精确监测农业用水量对于水和粮食安全至关重要,尤其是在面临气候变化的缺水地区.
- 在现场测量对于大规模,持续监测用水量是不切实际的.
- 卫星遥感为估计实际 EvapoTranspiration (ETa) 提供了一个替代方案,但云层覆盖和传感器问题的数据缺口需要填补缺口的方法.
研究的目的:
- 开发和验证一个填补差距的方法,以生成多年每月的ETA地图,空间分辨率为30米.
- 解决云层覆盖和卫星数据异常所带来的挑战,以持续监测用水量.
- 提供一种可重复的方法来评估大型河流流域的用水量.
主要方法:
- 使用基于Python的表面能量平衡模型PySEBAL模型来估计ETA.
- 使用局部加权回归 (LWR) 填补时间数据缺口.
- 使用splines的空间插值被应用来填补剩余的空白,利用Landsat 7和8数据对乌尔米亚湖盆地 (2013-2015) 的数据.
主要成果:
- 填补差距的方法成功地重建了各种农业用地的月度Eta动态,保持了高度的空间变化.
- 该方法的准确性很高,与粮农组织WaPOR数据相比,R2为0.93.
- 这种方法在一个大盆地 (52,970平方公里) 中被证明是有效的,并且可以扩展到其他地区.
结论:
- 开发的缺口填充的ETA绘图方法是监测大型河流盆地的农业用水量的可靠工具.
- 这种方法提高了ETA估计的连续性和空间细节,支持水资源管理.
- 该方法是可重复的,适用于面临水资源管理挑战的不同地理区域.
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