Abstract
A comprehensive understanding of drought evolution in the Yellow River Basin (YRB) is essential for effective drought mitigation and water resource management. Based on the daily‐scale Modified Comprehensive Meteorological Drought Index (MCI), this study analyzes the spatiotemporal characteristics of drought in the YRB over the past 60 years. The main findings are: The average annual drought days exceed 60, with high‐frequency areas (> 120 days) concentrated in the upper‐middle reaches junction, the eastern middle reaches, and the western lower reaches. Most areas show a decreasing trend in drought days, with the most significant reduction in the source region (20 days/decade). Drought regimes vary regionally: the source region experiences infrequent, short, and mild droughts; the middle‐lower section of the upper reaches has infrequent but prolonged and intense droughts; while most middle‐lower reaches face frequent, short‐duration, yet relatively high‐intensity droughts. Spring drought dominates (25%–40%), followed by summer drought (15%–30%), with spring–summer consecutive drought being the most common cross‐seasonal pattern. During drought events, precipitation deficits are more pronounced in the middle‐lower section of the upper reaches and the lower reaches. Evapotranspiration anomalies are generally higher in the middle‐lower reaches. Precipitation‐dominated droughts (20%–35%) mainly occur in the middle‐lower section of the upper reaches. Evapotranspiration‐aggravated droughts (25%–35%) are concentrated in the source region. Synergistic droughts (25%–30%) are mainly found in the eastern middle reaches, the lower reaches, and localized areas. Since 1961, precipitation‐dominated droughts have decreased, while evapotranspiration‐aggravated and synergistic droughts have increased in most parts of the YRB. Daily‐scale monitoring enables a more accurate characterization of drought processes, providing critical insights for regional drought management and supporting ecological conservation and high‐quality development in the basin.