Water shortages in Southern California made an indelible impression on Evelyn Wang ’00 when she was growing up in Los Angeles. “I was quite young, perhaps in first grade,” she says. “But I remember we weren’t allowed to turn our sprinklers on. And everyone in the neighborhood was given disinfectant tablets for the toilet and encouraged to keep flushing to a minimum. I didn’t understand exactly what was happening. But I saw that everyone in the community was affected by the scarcity of this resource.” Today, as extreme weather events increasingly affect communities around the world, Wang is leading MIT’s effort to tackle the interlinked challenges of a changing climate and a burgeoning global demand for energy. Last April, after wrapping up a two-year stint directing the US Department of Energy’s Advanced Research Projects Agency–Energy (ARPA-E), she returned to the campus where she’d been both an undergraduate and a faculty member to become the inaugural vice president for energy and climate.  “The accelerating problem of climate change and its countless impacts represent the greatest scientific, …