In April and May 2015, a bloom of toxic algae spanned more than a thousand miles of Pacific coastline, from Santa Barbara, Calif., to British Columbia. Marine organisms were poisoned throughout the food web, disrupting coastal ecosystems and economies for months. Similar events are expected to become more frequent as the oceans and atmosphere adjust to a warming climate. In the February issue of EARTH Magazine, read how scientists are working to better understand the 2015 Pacific bloom, hoping to apply lessons learned in responding to future events.