A now-closed Irish pub in Lawrence, Mass., displayed an old "Help Wanted/No Irish Need Apply" — a common sight across the country in the mid-1800s.
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Diver swimming over Elkhorn Coral in the Florida Keys. Elevated nutrients as well as elevated temperatures are causing a massive loss of this iconic branching species in Florida.
JW Porter/University of Georgia
Container ships and other maritime vessels currently run on pollutant-intensive heavy fuel oil. The world's largest container-shipping company, Maersk, has promised to make its operations zero carbon by 2050. Doing so will require using new fuels such as hydrogen.
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