1 Remote Sensing for Drought Monitoring & Impact Assessment: Progress, Past 2 Challenges and Future Opportunities 3 4 Harry West, Nevil Quinn & Michael Horswell 5 Centre for Water, Communities & Resilience; Department of Geography & Environmental 6 Management; University of the West of EnglanD, Bristol 7 8 CorresponDing Author: Harry West (
[email protected]) 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 1 24 Remote Sensing for Drought Monitoring & Impact Assessment: Progress, Past 25 Challenges and Future Opportunities 26 27 Abstract 28 Drought is a common hydrometeorological phenomenon anD a pervasive global hazarD. As 29 our climate changes, it is likely that Drought events will become more intense anD frequent. 30 Effective Drought monitoring is therefore critical, both to the research community in 31 Developing an unDerstanDing of Drought, anD to those responsible for Drought management 32 anD mitigation. Over the past 50 years remote sensing has shifteD the fielD away from 33 reliance on traditional site-baseD measurements anD enableD observations anD estimates of 34 key drought-relateD variables over larger spatial anD temporal scales than was previously 35 possible. This has proven especially important in Data poor regions with limiteD in-situ 36 monitoring stations. Available remotely senseD Data proDucts now represent almost all 37 aspects of Drought propagation anD have contributeD to our unDerstanDing of the 38 phenomena. In this review we chart the rise of remote sensing for Drought monitoring, 39 examining key milestones anD technologies for assessing meteorological, agricultural anD 40 hyDrological Drought events. We reflect on challenges the research community has faceD to 41 Date, such as limitations associateD with Data recorD length anD spatial, temporal anD 42 spectral resolution.