Xu Yawei, He Qing, Lu Hui, Yang Kun, Entekhabi Dara, Short Gianotti Daniel J
Department of Earth System Science, Institute for Global Change Studies, Tsinghua University, Beijing, 100084, China.
Department of Civil Engineering, The University of Tokyo, Tokyo, 113-8654, Japan.
Sci Data. 2025 Apr 30;12(1):722. doi: 10.1038/s41597-025-05048-y.
The critical point (CP) and permanent wilting point (PWP) are key soil hydraulic characteristics that control the land surface energy budget and water balance. There is a lack of available data for these parameters on the global scale. This study extracts CP and PWP through soil moisture drydown (SMD) and provides global yearly soil hydraulic properties from a long-term (2002-2023) remote-sensing soil moisture product (Neural Network-based Soil Moisture, NNsm). Validated against 1334 stations from the International Soil Moisture Network (ISMN), the results show that the global medians of CP and PWP based on the NNsm are robust over time, and outperform the Soil Moisture Active and Passive (SMAP) dataset in accuracy due to the advantage of daily temporal resolution. Furthermore, this dataset holds an advantage over existing products, as it is derived from a multi-year climatological mean state and solely from satellite-based soil moisture observation. The derived dataset is useful for those who wish to connect land-atmosphere characteristics with their interests, as well as calibrate land surface models.
临界点(CP)和永久凋萎点(PWP)是控制陆地表面能量平衡和水平衡的关键土壤水力特性。在全球范围内,这些参数缺乏可用数据。本研究通过土壤水分干涸(SMD)提取CP和PWP,并从长期(2002 - 2023年)的遥感土壤水分产品(基于神经网络的土壤水分,NNsm)中提供全球年度土壤水力特性。通过与国际土壤湿度网络(ISMN)的1334个站点进行验证,结果表明基于NNsm的CP和PWP的全球中位数随时间推移具有稳健性,并且由于每日时间分辨率的优势,在准确性方面优于土壤水分主动和被动(SMAP)数据集。此外,该数据集比现有产品具有优势,因为它是从多年气候平均状态推导而来,并且仅基于卫星土壤湿度观测。该推导数据集对于那些希望将陆地 - 大气特征与他们的兴趣联系起来以及校准陆地表面模型的人来说是有用的。