Researchers estimate that Greenland and Antarctica have lost about 11 trillion metric tons of ice since the 1970s, enough to raise global sea level by more than 3 centimeters. The assessment combined data from 27 satellite missions spanning more than 50 years. About 84 percent of the loss came from glaciers and ice sheets breaking off or flowing into the ocean, and only 16 percent from melting at the surface. Annual loss rose steeply, with Greenland going from 60 billion tons a year in the 1980s to 264 billion in the 2010s. Sea level rose about 1.4 millimeters a year through most of the twentieth century but over 3.6 millimeters a year between 2006 and 2015.

In 1909 D. W. Griffith made a 14-minute film about a speculator who corners the wheat market and doubles the price of bread. A farmer sows his field while a 'Wheat King' gambles in the Chicago wheat pit; bakers raise the loaf from five cents to ten and the poor line up for bread. Griffith cut back and forth between the farm, the feast and the breadline, a technique called parallel editing, so audiences saw both ends of the economy at once. The film drew on Frank Norris's stories and on a real scheme: months earlier Chicago financier James Patten had cornered wheat, sent bread prices up and made about $5 million, roughly $185 million today.