As this story notes, "air freight is responsible for a quarter of the value of all goods moved into and out of the UK." And a variety of poorer countries are getting hit even harder: Businessweek reports that flower and vegetable farms in Ethiopia have already lost $2.36 million due to all the canceled flights. I wrote a longer piece about this topic a few years ago, but greenhouse-gas emissions from airplanes will almost certainly be some of the hardest to cut, since we've become so dependent on flight, there's no easy substitute, and there don't appear to be any technological fixes around the corner.
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