Snow cover and snow water equivalent for: How do tradeoffs in satellite spatial and temporal resolution impact snow water equivalent reconstruction?

Given the tradeoffs between spatial and temporal resolution, questions about resolution optimality are fundamental to the study of global snow. Answers to these questions will inform future scientific priorities and mission specifications. Heterogeneity of mountain snowpacks drives a need for daily snow cover mapping at the slope scale (≤ 30 m) that is unmet for a variety of scientific users, ranging from hydrologists to the military to wildlife biologists. But finer spatial resolution usually requires coarser temporal or spectral resolution. Thus, no single sensor can meet all these needs. Recently, constellations of satellites and fusion techniques have made noteworthy progress. The efficacy of two such recent advances is examined: 1) a fused MODIS - Landsat product with daily 30 m spatial resolution; and 2) a harmonized Landsat 8 - Sentinel 2A/B (HLS) product with 2–3-day temporal and 30-m spatial resolution. State-of-art spectral unmixing techniques are applied to surface reflectanc..., ,

考虑到空间分辨率与时间分辨率之间存在权衡取舍，分辨率最优性相关问题是全球积雪研究的核心议题。对这些问题的解答将为未来的科学研究优先级设定与任务规范制定提供参考依据。山地积雪的异质性使得科研领域亟需开展坡面尺度（≤30米）的每日积雪覆盖制图，但当前该需求尚未得到充分满足，相关用户涵盖水文学家、军事科研人员以及野生动物生物学家等多个领域。但更高的空间分辨率通常需要以更低的时间分辨率或光谱分辨率作为代价，因此单一传感器无法同时满足所有此类需求。近年来，卫星星座与数据融合技术已取得显著进展。本研究针对两项近期技术进展的应用效能展开评估：其一为融合中分辨率成像光谱仪（MODIS）与陆地卫星（Landsat）的数据产品，可实现每日30米空间分辨率的观测；其二为标准化匹配后的陆地卫星8号与哨兵卫星2A/B（HLS）数据产品，具备2-3天的时间分辨率与30米空间分辨率。本研究将当前前沿的光谱解混技术应用于地表反射率（surface reflectance）数据……