Recent climate patterns are affecting seasonal water residence times and water temperatures in Puget Sound

At the end of 2014 water temperatures in Puget Sound rapidly increased in response to The Blob and persisted into 2017. Climate anomalies on land caused premature snow melt and freshening of Puget Sound. The seasonal shift in freshwater delivery increased winter estuarine circulation allowing greater import of heat from the ocean but decreased summer circulation, retaining more heat in Puget Sound in summer. In both seasons, Puget Sound temperatures increased affecting water quality and ecosystem performance. We contrast salinity, temperature, and density records from 2014-2017 to infer residence time and changes in water masses during the extreme climate years. Increased winter temperatures >8C might have promoted overwintering for temperature sensitive species such as anchovy.