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Multi-Sensor Remote Sensing for Drought Characterization: Current Status, Opportunities and a Roadmap for the Future

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Multi-Sensor Remote Sensing for Drought Characterization: Current Status, Opportunities and a Roadmap for the Future Remote Sensing of Environment 256 (2021) 112313 Contents lists available at ScienceDirect Remote Sensing of Environment journal homepage: www.elsevier.com/locate/rse Multi-sensor remote sensing for drought characterization: current status, opportunities and a roadmap for the future Wenzhe Jiao a, Lixin Wang a,*, Matthew F. McCabe b a Department of Earth Sciences, Indiana University-Purdue University Indianapolis (IUPUI), Indianapolis 46202, USA b Hydrology, Agriculture and Land Observation Group, Water Desalination and Reuse Center, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia ARTICLE INFO ABSTRACT Keywords: Satellite based remote sensing offers one of the few approaches able to monitor the spatial and temporal Data fusion development of regional to continental scale droughts. A unique element of remote sensing platforms is their Drought multi-sensor capability, which enhances the capacity for characterizing drought from a variety of perspectives. Drought impact Such aspects include monitoring drought influences on vegetation and hydrological responses, as well as Drought monitoring assessing sectoral impacts (e.g., agriculture). With advances in remote sensing systems along with an increasing Ecohydrology Multi-sensor satellite range of platforms available for analysis, this contribution provides a timely and systematic review of multi- Regional scale drought 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 re­ view 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 benefitsfor regional to global drought studies, particularly in: 1) revealing the complex drought impact mechanisms on ecosystem components; 2) providing continuous long-term drought related in­ formation 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, mi­ crowave, 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. (continued ) Acronym dictionary COT Cloud OpticalThickness AGC Aboveground Carbon ECOSTRESS ECOsystem Spaceborne Thermal Radiometer Experiment on Space AMS American Meteorological Society Station AOD Aerosol Optical Depth EDDI Evaporative Demand Drought Index ASCAT Advanced Scatterometer ENSO El Nino-Southern Oscillation AVHRR Advanced Very High Resolution Radiometer EPMC Evolution Process-based Multi-sensor Collaboration BRT Boosted Regression Trees ERSATSR European Remote Sensing Satellite–Along Track Scanning CART Classification And Regression Tree Radiometer CCI Climate Change Initiative ESA European Space Agency CDMI Combined Drought Monitoring Index ESI Evaporative Stress Index (continued on next column) (continued on next page) * Corresponding author. E-mail address: [email protected] (L. Wang). https://doi.org/10.1016/j.rse.2021.112313 Received 27 July 2020; Received in revised form 16 December 2020; Accepted 18 January 2021 Available online 5 February 2021 0034-4257/© 2021 Elsevier Inc. All rights reserved. W. Jiao et al. Remote Sensing of Environment 256 (2021) 112313 (continued ) (continued ) FDA Flexible Discriminant Analysis USGS United States Geological Survey FIDI Fuzzy Integrated Drought Index VCI Vegetation Condition Index FLEX FLuorescence EXplorer VegDRI Vegetation Drought Response Index fPAR fraction of absorbed Photosynthetic Active Radiation VIS/IR Visible and Infrared Radiation GEDI Global Ecosystem Dynamics Investigation VOD Vegetation Optical Depth GEO Geostationary Earth orbit VPD Vapor Pressure Deficit GFED Global Fire Emissions Database GNSS Global Navigation Satellite System GPCP Global Precipitation Climatology Project GPP Gross Primary Productivity GRACE Gravity Recovery and Climate Experiment 1. Introduction GWR Geographically Weighted Regression HiFIS High-Fidelity Imaging Spectroscopy Drought is routinely described as a naturally occurring phenomenon HLS Harmonized Landsat and Sentinel-2 induced by precipitation deficiency and consequent hydrological HSMDI High resolution Soil Moisture Drought Index ICESat-2 Ice, cloud, and land elevation satellite-2 imbalance (Pachauri et al., 2014; Trenberth et al., 2014). Drought can IDI Integrated Drought Index occur over all climatic conditions and has a wide range of damaging IMS Ice Mapping System impacts (Dai, 2011; Vicente-Serrano et al., 2019). For instance, it can INFORM Invertible FOrest Reflectance Model cause crop failures, which may lead to substantial food security concerns InSAR Interferometry of Synthetic Aperture Radar and financial losses (Daryanto et al., 2015; Daryanto et al., 2016; God- ISDI Integrated Surface Drought Index JAXA Japan Aerospace Exploration Agency fray et al., 2010; Pandey et al., 2007); it can decrease the volumes of KECA Kernel Entropy Component Analysis source waters from rivers, lakes, and groundwater, directly impacting LAI Leaf Area Index water availability, distribution, and energy supply (Van Loon, 2015); it LEO Low Earth Orbit can also amplify tree mortality, trigger ecosystem fires, and decrease LFMC Live Fuel Moisture Content LiDAR Light Detection And Ranging carbon uptake in vegetation (Allen et al., 2010; Ciais et al., 2005; Zhao LST Land Surface Temperature and Running, 2010), thereby influencingterrestrial carbon storage and MAIAC Multi-Angle Implementation of Atmospheric Correction sequestration potential. Given the wide-ranging scope of influencesand MARS Multivariate Adaptive Regression Splines impacts that droughts can have, it is no surprise that it is often classified MIDI Microwave Integrated Drought Index quite broadly, based on the different systems affected. These classifica- MODIS Moderate Resolution Imaging Spectroradiometer MRMS Multi-Radar Multi-Sensor tions generally fall into: i) agricultural; ii) hydrological; iii) meteoro- NASA National Aeronautics and Space Administration logical, and iv) socioeconomic drought (Wilhite and Glantz, 1985). NDII Normalized Difference Infrared Index Recent research has suggested additional drought types, such as NDVI Normalized Difference Vegetation Index ecological drought (Crausbay et al., 2017), environmental drought NDWI Normalized Difference Water Index NIR Near Infrared Radiation (Vicente-Serrano et al., 2019), and flash drought (Otkin et al., 2018; NIRV Near-infrared Reflectance of vegetation Svoboda et al., 2002). With the severity and frequency of droughts NISAR NASA-ISRO Synthetic Aperture Radar projected to increase under climate change, understanding the interre- NLDAS-2 North American Land Data Assimilation System-2 lated impacts and influence across and within sectors is an issue of NOAA National Oceanic and Atmospheric Administration considerable importance (Dai, 2013; Trenberth et al., 2014; Xu et al., OMDI Optimized Meteorological Drought Index OVDI Optimized Vegetation Drought Index 2019; Zhou et al., 2019). Figure 1 illustrates a number of these drought PADI Process-based Accumulated Drought Index impacts on different ecosystem components, together with the feedbacks PAR Photosynthetically Active Radiation between drought and climate. PCA Principal Component Analysis Given the spatial and temporal advantage that remote sensing can PCI Precipitation Condition Index PDSI Palmer Drought Severity Index offer, data from a range of satellite-based platforms have played an PERSIANN Precipitation Estimation from Remotely Sensed Information using increasingly important role in drought studies over the last decade Artificial Neural Networks (AghaKouchak et al., 2015; West et al., 2019). In addition, advances in PHDI Palmer Hydrologic Drought Index algorithm development and the rise of cloud-based computing and PLSR Partial Least Squares Regression storage capacity have greatly enhanced the application potential of PRI Photochemical Reflectance index QuickDRI Quick Drought Response Index remote sensing for drought studies (Abdelwahab et al., 2014; Faghmous RCI Rapid Change Index and Kumar, 2014; Huntington et al., 2017; Sellars et al., 2013; Zhou RF Random Forests et al., 2016). Apart from offering an independent observational capacity, RTM Radiative Transfer Models remote sensing data provides an opportunity to reduce uncertainty and SDCI Scaled Drought Condition Index SDI Synthesized Drought Index constrain modelling efforts directed towards drought prediction (Smith SESR Standardized Evaporative Stress Ratio et al., 2016). With all of these advances,
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