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使用FLUXNET2015数据评估全球流量塔埃迪-共变量测量的空间代表性
Junjun Fang1,2, Jingchun Fang1,2, Baozhang Chen3,4,5
1State Key Laboratory of Resource and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China.
Scientific data
|June 3, 2024
概括
本研究评估了来自FLUXNET2015.5.的全球-协变 (EC) 流量塔测量的空间代表性. 它提供了一个数据集,以指导研究人员通过了解测量足迹来更有效地使用EC流量数据.
科学领域:
- 地球和环境科学 地球和环境科学
- 大气科学 大气科学
- 生态生态学 生态生态学
背景情况:
- 像FLUXNET2015这样的Eddy-covariance (EC) 流量数据集对于验证遥感产品和基准测试模型至关重要.
- 一个关键的挑战是理解EC塔测量所代表的空间尺度,称为流量足迹.
- 流量足迹和目标区域 (例如模型网格单元) 之间的不匹配可以引入偏差.
研究的目的:
- 使用FLUXNET2015数据集分析全球EC测量的空间代表性.
- 根据足迹分析创建一个全面的数据集,评估流量塔的代表性.
- 为研究人员提供指导,以改善EC流量数据的利用.
主要方法:
- 使用了开源的FLUXNET2015数据集和流量足迹模型 (SAFE-f).
- 计算了气候学年度累积足迹 (ACFC),并将其覆盖在土地覆盖面和植被指数数据上.
- 开发了一个数据集,包括ACFC轮,土地覆盖比例,NDVI半变量图和传感器位置偏差 (SLB).
主要成果:
- 生成了全球流量塔的空间代表性数据集.
- 使用ACFC量化了EC测量的空间范围,并根据土地覆盖面,半波量图和SLB评估了代表性.
- 分类网站的代表性分为三个级别.
结论:
- 开发的数据集为FLUXNET2015数据的空间代表性提供了有价值的见解.
- 这项工作旨在为使用EC流量测量的国际研究人员增强数据质量指导.
- 更好地了解流量足迹的空间特征将尽量减少模型验证和遥感产品评估中的偏差.
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