.FOR CALIFORNIANS it seemed like du00e9ju00e0 vu. In 2013 a procession of hurricanes, sustained by climatic rivers, killed a minimum of 21 people and induced virtually $5bn-worth of damages across the state. On February fourth this year the same form of storm once again ravaged. Hurricane-strength winds buffeted the core coastline near Huge Sur. In Los Angeles personalities were saturated as they arrived at the Grammy awards' ceremony. Estates in the Hollywood Hillsides were dealt with in mud. At the very least three folks have actually perished. What are actually climatic waterways, and are they a threat beyond California?