Since 1950, zero oxygen zones went up more than fourfold in the ocean, and more than 10-fold in coastal waters. Scientists expect oxygen to continue dropping even outside these zones as Earth warms. To halt the decline, the world needs to rein in both climate change and nutrient pollution

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Since 1950, zero oxygen zones went up more than fourfold in the ocean, and more than 10-fold in coastal waters. Scientists expect oxygen to continue dropping even outside these zones as Earth warms. To halt the decline, the world needs to rein in both climate change and nutrient pollution