World’s Rivers Are Driest They Have Been in Decades

Dry stretches along the Rio Negro, a tributary of the Amazon River, in October 2023.

Dry stretches along the Rio Negro, a tributary of the Amazon River, in October 2023. NASA

Last year, the world’s rivers had their driest year in at least three decades, according to a new U.N. report, which warns that heat and drought are sapping vital waterways.

Warming is fueling both heavier rainfall and more intense drought globally. As the planet heats up, “we are facing growing problems of either too much or too little water,” said Celeste Saulo, secretary-general of the U.N. World Meteorological Organization, which authored the new report.

In 2023, the hottest year on record, the Mississippi River and Amazon River basins were at all-time lows, while the Ganges, Brahmaputra, and Mekong rivers, which all have their headwaters in the Himalayas, were also unusually dry. Across nearly half the globe, rivers were drier than normal.

Last year also saw severe heat shrink glaciers that are a crucial source of meltwater. Glaciers worldwide lost more ice in 2023 than they have in at least five decades, with glaciers in Europe and North America hit particularly hard.

“Melting ice and glaciers threaten long-term water security for many millions of people,” Saulo said. “And yet we are not taking the necessary urgent action.”

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