Satellite based remote sensing offers one of the few approaches able to monitor the spatial and temporal development of regional to continental scale droughts. A unique element of remote sensing platforms is their multi-sensor capability, which enhances the capacity for characterizing drought from a variety of perspectives. Such aspects include monitoring drought influences on vegetation and hydrological responses, as well as assessing sectoral impacts (e.g., agriculture). With advances in remote sensing systems along with an increasing range of platforms available for analysis, this contribution provides a timely and systematic review of multi-sensor remote sensing drought studies, with a particular focus on drought related datasets, drought related phenomena and mechanisms, and drought modeling. To explore this topic, we first present a comprehensive summary of large-scale remote sensing datasets that can be used for multi-sensor drought studies. We then review the role of multi-sensor remote sensing for exploring key drought related phenomena and mechanisms, including vegetation responses to drought, land-atmospheric feedbacks during drought, drought-induced tree mortality, drought-related ecosystem fires, post-drought recovery and legacy effects, flash drought, as well as drought trends under climate change. A summary of recent modeling advances towards developing integrated multi-sensor remote sensing drought indices is also provided. We conclude that leveraging multi-sensor remote sensing provides unique benefits for regional to global drought studies, particularly in: 1) revealing the complex drought impact mechanisms on ecosystem components; 2) providing continuous long-term drought related information at large scales; 3) presenting real-time drought information with high spatiotemporal resolution; 4) providing multiple lines of evidence of drought monitoring to improve modeling and prediction robustness; and 5) improving the accuracy of drought monitoring and assessment efforts. We specifically highlight that more mechanism-oriented drought studies that leverage a combination of sensors and techniques (e.g., optical, microwave, hyperspectral, LiDAR, and constellations) across a range of spatiotemporal scales are needed in order to progress and advance our understanding, characterization and description of drought in the future.

基于卫星的遥感技术是能够监测区域到大陆规模干旱的时空发展的少数方法之一。遥感平台的独特元素是其多传感器功能，可以从多种角度增强表征干旱的能力。这些方面包括监测干旱对植被和水文响应的影响，以及评估部门影响（例如农业）。随着遥感系统的进步以及可用于分析的平台范围的扩大，这一贡献为多传感器遥感干旱研究提供了及时，系统的回顾，特别关注干旱相关的数据集，干旱相关的现象和机制，以及干旱建模。要探索这个话题，我们首先介绍可用于多传感器干旱研究的大规模遥感数据集的综合摘要。然后，我们回顾了多传感器遥感在探索与干旱相关的关键现象和机制方面的作用，包括植被对干旱的响应，干旱期间的陆地大气反馈，干旱引起的树木死亡，干旱相关的生态系统火灾，干旱后的恢复以及遗留效应，旱灾以及气候变化下的干旱趋势。还提供了对开发集成的多传感器遥感干旱指数的最新模型进展的总结。我们得出的结论是，利用多传感器遥感技术可以为区域乃至全球干旱研究提供独特的好处，特别是：1）揭示了复杂的干旱对生态系统组成部分的影响机制；2）大规模连续提供与干旱有关的长期信息；3）以高时空分辨率呈现实时干旱信息；4）提供多条干旱监测证据，以提高建模和预测的鲁棒性；5）提高干旱监测评估工作的准确性。我们特别强调指出，需要进行跨越机械时空范围的，结合传感器和技术（例如，光学，微波，高光谱，LiDAR和星座）组合的面向机制的干旱研究，以推进和推进我们的理解，表征以及对未来干旱的描述。4）提供多条干旱监测证据，以提高建模和预测的鲁棒性；5）提高干旱监测评估工作的准确性。我们特别强调指出，需要进行跨越机械时空范围的，结合传感器和技术（例如，光学，微波，高光谱，LiDAR和星座）组合的面向机制的干旱研究，以推进和推进我们的理解，表征以及对未来干旱的描述。4）提供多条干旱监测证据，以提高建模和预测的鲁棒性；5）提高干旱监测评估工作的准确性。我们特别强调指出，需要进行跨越机械时空范围的，结合传感器和技术（例如，光学，微波，高光谱，LiDAR和星座）组合的面向机制的干旱研究，以促进和推进我们的理解，表征以及对未来干旱的描述。