A world with a sudden limit on air travel would be tremendously different from the one we live in now.
Some Western states have collaborative water agreements with Indian tribes - Washington state, for instance, monitors a number of its rivers to protect spawning salmon, which are promised to native peoples under 19th-century treaties.
Obama issued a slew of executive orders about climate change during the eight years of his presidency. Inexplicably, President Trump revoked about half of them but left the other half in place. Since Obama's orders were intertwined, it's unclear exactly what applies.
Seoul and Shanghai, Jaipur and Jakarta; shining skyscrapers, pricey hotels, traffic-jammed streets ablaze with neon - all were built atop a foundation of laboratory-bred rice.
Smartphones can relay patients' data to hospital computers in a continuous stream. Doctors can alter treatment regimens remotely, instead of making patients come in for a visit.
The Paris pact was correctly described by its opponents - greens and anti-greens alike - as toothless. But it was also the first time that nations around the world had officially agreed that climate change was a problem and that concrete steps should be taken to avoid its worst effects.
