Arctic could be ice-free a decade earlier than thought

The Arctic Ocean's ice cap will disappear in summer as soon as the 2030s and a decade earlier than thought, no matter how aggressively humanity draws down the carbon pollution that drives global warming, scientists said Tuesday.

River deltas: Valuable and under threat

The livelihoods of millions of people who live in river deltas, among the world's most productive lands, are at risk. Created where large rivers meet the ocean and deposit their natural sediment load, river deltas are often ...

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