Excerpt:
The state is being tossed between awful climate extremes.
In the Talmudic parable of Honi the Circle Maker, the drought-stricken people of Jerusalem send up a prayer that God should deliver them rain. And sure enough, after a few false starts, he does. Except that once the rain starts, it won’t let up. It pours and pours until the people are forced to flee to higher ground, their homes flooded by the answer to their prayer.
That, minus the whole divine-intervention part, is roughly the situation that California currently finds itself in. After years of virtually unremitting drought, the state is now suddenly, tragically, swamped with an overabundance of water. Over the past couple of weeks, a series of intense storms has caused massive, widespread flooding. On Sunday evening, the president declared a state of emergency, and by the next day, more than 90 percent of the state’s residents were under flood watch. At least 17 people have died—that number is likely to rise—and tens of thousands more have been forced to evacuate. When the storms finally subside, the cost of the damage is expected to exceed $1 billion. But we still have a ways to go: Weather forecasters expect the heavy rain to continue for at least another week, along with lightning and hail. Tornadoes are not out of the question.
The flooding is the product of a weather phenomenon known as an “atmospheric river,” a long, thin channel of water vapor like a river in the sky. Atmospheric rivers funneled in from the Pacific are fairly common in California and are not in and of themselves bad news. Each year, the state depends on them to replenish its reservoirs ahead of the summer months, when it sees hardly any rain at all. Daniel Horton, a climate scientist at Northwestern University, told me that atmospheric rivers often supply more than 50 percent of the state’s annual water…
