Consider the life of a current college sophomore, a 20-year-old. She was born in 1998, at the time the warmest year ever measured, when a monster El Niño pattern spawned floods and droughts around the world. Seven years later, as she started first grade, Hurricane Katrina inundated New Orleans, and 2005 set a new record as the warmest year ever measured. That record fell again as she started fifth grade and sixth grade, and in her sophomore, junior, and senior years of high school.