High-resolution spatially explicit land surface model calibration using field-scale satellite-based daily evapotranspiration product
High-resolution spatially explicit land surface model calibration using field-scale satellite-based daily evapotranspiration product
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DOI：
10.1016/j.jhydrol.2020.125730
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发表时间：
2020-11
影响因子：
6.4
通讯作者：
Yi Yang;K. Guan;B. Peng;M. Pan;Chongya Jiang;T. Franz
中科院分区：
文献类型：
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作者：
Yi Yang;K. Guan;B. Peng;M. Pan;Chongya Jiang;T. Franz
整个农业景观的水预算的高分辨率模拟对于精准农业、水资源管理和环境质量评估等各种应用至关重要。模型数据集成已被证明是减少模型不确定性的有效方法，并且近几十年来通过卫星数据进行空间显式校准来改进地表建模的机会越来越多。最近，开发了基于卫星的日30米分辨率蒸散（ET）产品BESS-STAIR，实现了高性能，很好地捕捉了美国玉米带蒸散的时空动态。为了探索高分辨率空间显式校准在精细尺度上推进地表建模的潜力，我们使用新开发的 BESS-STAIR ET 对农田上的 Noah-MP 地表模型 (LSM) 进行了校准实验。我们首先使用 Sobol 敏感性分析来确定 Noah-MP 的 ET 模拟中最敏感的参数。使用 BESS-STAIR ET 校准最敏感的植被（最小气孔阻力）和土壤参数（饱和导水率、饱和基质势和土壤孔径分布参数），以改进地表水平衡的模型模拟。我们在美国玉米带种植玉米和大豆的 8 个涡流协方差通量塔地点进行了校准实验，并对伊利诺伊州尚佩恩的 Spoon 河流域进行了区域校准研究。当以通量塔测量为基准时，BESS-STAIR ET 校准模型（由通量塔强制驱动）平均将玉米每小时 ET 的 RMSE 从 61W/m2 降低至 47W/m2，将大豆从 66W/m2 降低至 53W/m2，并且与使用通量塔测量的 ET 直接校准的性能相匹配。区域研究发现，使用 BESS-STAIR ET 进行校准还改进了长期区域水收支的模拟，并且与使用水流的传统集总校准相比，获得了更好的 ET 性能。进一步分析发现，高分辨率定标可以在一定程度上解决蒸散的空间变化，定标的准确性很大程度上归功于BESS-STAIR 蒸散数据本身的低偏差和良好的长期相关性。因此，我们的研究证明了高分辨率模型校准的有效性，并为现场规模水文建模和精准农业应用提供了重要意义。
High-resolution simulation of water budgets across the agricultural landscape is critically important to a variety of applications, such as precision agriculture, water resources management, and environmental quality assessment. Model-data integration has been shown to be an effective approach to reduce model uncertainties and there is a growing opportunity to improve land surface modeling through spatially explicit calibration with satellite data in recent decades. Recently, a satellite-based daily 30-m resolution evapotranspiration (ET) product BESS-STAIR has been developed, achieving a high performance and well capturing the spatial and temporal dynamics of ET across the U.S. Corn Belt. To explore the potential of high-resolution spatially explicit calibration for advancing land surface modeling at fine scales, we carried out calibration experiments for the Noah-MP land surface model (LSM) over cropland using this newly developed BESS-STAIR ET. We first used Sobol sensitivity analysis to identify the most sensitive parameters for the Noah-MP’s ET simulation. The most sensitive vegetation (minimum stomatal resistance) and soil parameters (saturated hydraulic conductivity, saturated matric potential, and a soil pore size distribution parameter) were calibrated using BESS-STAIR ET to improve model simulation of surface water balance. We conducted calibration experiments at 8 eddy covariance flux tower sites that grew maize and soybean across the U.S. Corn Belt, as well as a regional calibration study on the Spoon River watershed in Champaign, Illinois. When benchmarked with flux tower measurements, the BESS-STAIR ET–calibrated model (driven by flux tower forcing) on average reduced the RMSE of hourly ET from 61 W/m2to 47 W/m2for maize, and from 66 W/m2to 53 W/m2for soybean, and matched the performance of directly calibrating using flux tower measured ET. The regional study found that calibration using BESS-STAIR ET also improved the simulation of long-term regional water budgets and achieved better performance of ET than traditionally lumped calibration using streamflow. Further analysis revealed that the high-resolution calibration can resolve the spatial variations of ET to a certain extent, and the accuracy of the calibration can be largely attributed to the low bias and excellent long-term correlation of the BESS-STAIR ET data itself. Our study thus demonstrates the effectiveness of high-resolution model calibration and provides important implications in field-scale hydrological modeling and precision agricultural applications.