Extreme ocean temperatures in the Coral Sea surrounding Australia's Great Barrier Reef hit their highest levels in at least four centuries this year, scientists reported on Wednesday.
Why it matters: Extreme ocean heat can trigger mass coral bleaching events, making coral more vulnerable to heat and other stress.
A ballooning number of spying technologies inside and outside Earth's atmosphere are making military maneuvers and materiel nearly impossible to hide.
Why it matters: Concealment and surprise have long been winning tenets of warfare. But these ever-watching eyes complicate the calculus of what gear to buy, how to move and where to dig in.
