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一个统一的集体土壤湿度数据集遍及美国大陆
Lingcheng Li1, Xinming Lin1, Yilin Fang1
1Pacific Northwest National Laboratory, 902 Battelle Blvd, Richland, WA, 99354, United States.
Scientific data
|April 1, 2025
概括
一个新的土壤湿度 (SM) 数据包统一了整个美国大陆 (CONUS) 的19个不同的数据集. 分析揭示了独特的区域SM模式和模型特定的偏见,有助于干旱影响评估.
科学领域:
- 地球科学 地球科学 地球科学
- 水文学的水文学
- 环境科学 环境科学
背景情况:
- 土壤湿度是影响陆地与大气相互作用和干旱动态的关键变量.
- 现有的土壤湿度数据集往往缺乏分辨率和方法的标准化,这阻碍了全面的分析.
- 了解时空的土壤湿度变化对于气候建模和水资源管理至关重要.
研究的目的:
- 为美国大陆 (CONUS) 开发一个统一的土壤湿度 (SM) 数据包.
- 分析不同地区和气候区的表面SM的时空变异性.
- 评估各种SM数据集之间的差异,并为地球系统模型评估和干旱影响量化提供框架.
主要方法:
- 开发一个统一的数据包,整合了来自陆地表面模型,遥感,再分析和机器学习的19个产品.
- 将所有数据集标准化为0.25度和每月的时空分辨率.
- 使用Kopen-Geiger气候分类和波纹功率频谱分析在现场观测上的统计分析.
主要成果:
- 确定了明显的土壤湿度模式:西部CONUS显示出更高的变化,东部CONUS具有更高的SM值.
- 在数据集类型之间观察到的差异:遥感数据通常表明更干燥的条件,而再分析产品则表明更潮湿的条件.
- 在现场数据的波形分析有助于解释跨数据集的时间尺度差异,促进日常SM记录重建.
结论:
- 统一的SM数据包和分析框架为水文研究提供了全面的资源.
- 这些发现支持改进地球系统模型评估,不确定性量化和干旱影响评估.
- 这项研究为加强干旱应对计划和理解陆地与大气相互作用提供了基础.
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