Dynamic Variations of Agricultural Drought and Its Response to Meteorological Drought: A Drought Event‐Based Perspective.

The dynamic variations of agricultural drought can reflect the water shortage situation of the agricultural system, and there is a progressive relationship in the response of agricultural drought to meteorological drought on a spatiotemporal scale. In this study, the vegetation health index and the standardized precipitation evapotranspiration index were adopted as agricultural and meteorological drought indicators, respectively. Additionally, using the three‐dimensional spatiotemporal clustering technology, the dynamic evolutions of typical drought events were clarified, and the spatiotemporal response characteristics of agricultural drought to meteorological drought were revealed. The results indicated that: (a) there were 81 agricultural drought events in the North China Plain (NCP) during 1982–2020, with a largest drought severity (12.82 × 104 month km2), a 6‐month duration, and a 23.24 × 104 km2 affected area occurring in the No. 4 event; (b) from the 1980s to the 2010s, the agricultural drought gradually decreased and large‐scale droughts mainly concentrated in the border areas of Hebei, Shandong, and Henan; and (c) a total of 13 drought event pairs were successfully matched in the NCP, including 7 pairs of "one‐to‐one," 4 pairs of "one‐to‐many," 1 pair of "many‐to‐one," and 1 pair of "many‐to‐many." The spatiotemporal responses of agricultural drought were elucidated in a three‐dimensional perspective, which can propose a new approach for establishing drought propagation model, predicting future agricultural drought conditions, improving ecological environment quality, and can also be applied for the investigation of other drought types. Plain Language Summary: There is a certain delay effect and time lag between agricultural drought and meteorological drought, thus, it is crucial to investigate the dynamic variation of agricultural drought and its response to meteorological drought to understand the impact of climate change on vegetation, which has important scientific significance and application value for improving ecological environment quality and restoring ecosystem functions. However, the dynamic variation of agricultural drought and its response to meteorological drought are still unclear from a three‐dimensional perspective. Based on the Center for Satellite Applications and Research and Famine Early Warning Systems Network Land Data Assimilation System data set, the vegetation health index and the standardized precipitation evapotranspiration index were adopted as agricultural and meteorological drought indicators, respectively. Additionally, using the three‐dimensional spatiotemporal clustering technology, the temporal variations and spatial patterns of drought were explored, the dynamic evolutions of typical drought events were clarified, and the spatiotemporal response characteristics of agricultural drought to meteorological drought were revealed from a three‐dimensional perspective. This study sheds new viewpoints into the identification of agricultural drought variation and its relationships with meteorological drought, which can also be applied in other areas. Key Points: There were 81 agricultural drought events in the North China Plain during 1982–2020The drought gradually decreased from the 1980s to the 2010sA total of 13 drought event pairs were successfully matched [ABSTRACT FROM AUTHOR]