Pandemic. War. Now drought. Olive groves have shriveled in Tunisia. The Brazilian Amazon faces its driest season in a century. Wheat fields have been decimated in Syria and Iraq, pushing millions more into hunger after years of conflict. The Panama Canal, a vital trade artery, doesn’t have enough water, which means fewer ships can pass through. And the fear of drought has prompted India, the world’s biggest rice exporter, to restrict the export of most rice varieties. The United Nations estimates that 1.84 billion people worldwide, or nearly a quarter of humanity, were living under drought in 2022 and 2023, the vast majority in low- and middle-income countries. “Droughts operate in silence, often going unnoticed and failing to provoke an immediate public and political response,” wrote Ibrahim Thiaw, head of the United Nations agency that issued the estimates late last year, in his foreword to the report.