Season’s greetings, travelers! Here’s something new to worry about: Your trip may be disrupted by drones. London Gatwick, Britain’s second-busiest airport, had to be shut twice after unmanned aerial vehicles entered its airspace in what police called a “deliberate act.” Some 10,000 passengers were diverted, hundreds of flights were delayed, and chaos reigned on the ground. The army had to ...

This hasn’t been the best of years for those of us who worry about climate change. The US administration has firmly turned against emissions controls. State backing for construction pushed China’s emissions higher. And, far from peaking or even stagnating, worldwide emissions actually increased at the fastest rate in the past seven years, according to the Global Carbon Project. The ...

Like the Nasdaq, emerging markets are no strangers to booms and busts. Unlike the US market, valuations no longer matter much outside the developed world. That’s because sell-side analysts’ earnings estimates are unreliable. The 10% correction in the Nasdaq 100 Index shouldn’t have surprised US analysts — they’ve been revising down earnings estimates since April, when trade tensions started to ...