Denver Business Journal — United Airlines made history Thursday by becoming the first United States-based airline to publicly commit to significantly reducing its greenhouse gas emissions.

In an op-ed piece penned by United CEO Oscar Munoz, Munoz said United’s goal is to reduce the carrier’s greenhouse gas emissions by 50 percent by the year 2050. The move to significantly reduce those emissions is part of United’s oft-stated mission to be the world’s most environmentally-conscious airline.

United’s announcement is timed to coincide with a Global Climate Action Summit underway in San Francisco.

Per United calculations, reducing greenhouse gas emissions by 50 percent would eliminate 21 million metric tons of carbon dioxide in the atmosphere per year — the equivalent of taking 4.5 million cars off the road. That represents all the cars now in use in New York City and Los Angeles combined.

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