Puget Sound Metrics Dashboard

The metrics presented here are intended to inform resource managers, scientists, health officials, and others on how key climate and ocean factors may influence the present state of Puget Sound and to put current conditions in context of past observations. The metrics include estuarine flow, temperature changes from surface heat fluxes, salinity changes from rivers and rain, water column dissolved oxygen, and ocean boundary conditions. These were designed to be used to evaluate how changes in these factors may be connected to observed ecological and/or water quality changes. Our aim is to offer insights on why changes may be occurring. The metrics will be automatically updated weekly using available real-time measurements from buoys and other sources. The Puget Sound Metrics were developed as a Puget Sound Ecosystem Monitoring Program (PSEMP) project with funding from the Puget Sound Partnership.

Estuarine Flow tells us how fast Puget Sound’s waters are moving. Estuarine circulation determines flushing times (or residence times) of Puget Sound’s many basins. This in turn, influences how long or how much suspended or dissolved matter (e.g., larvae or contaminants) is retained or flushed out. Yet the timing and strength of the estuarine exchange can vary dramatically, seasonally and between basins.

Temperature Changes from Surface Heat Fluxes tells us how weather affects Puget Sound’s temperature. Water temperature changes in Puget Sound can be driven by both source water changes and changes in the local input or loss of heat. This metric tracks anomalies in the heat that enters or leaves Puget Sound through the water’s surface.

Salinity Changes from Rivers and Rain tells us what causes salinity to change. Changes in Puget Sound salinity can affect estuarine circulation as well as water column stratification, both of which can drive ecological processes. For instance, the strength of stratification can influence when or whether phytoplankton bloom. Since salinity in Puget Sound can change due to its oceanic source water or from freshwater input from rivers, precipitation, and groundwater, there is often uncertainty as to what causes salinity to change.

Water Column Dissolved Oxygen tells us how much of the water-column habitat has oxygen at levels that may not be at sufficient levels for particular organisms to thrive. The amount of oxygen available to organisms varies by location and time. This metric quantifies the amount of water column habitat for two different oxygen ranges: hypoxic (DO <2 mg/l), and potentially stressful (DO <5 mg/l). Tracking this metric can illuminate when and where in Puget Sound potential ecological impacts may occur due to low dissolved oxygen.

Ocean Boundary Conditions tells us how the ocean affects Puget Sound. Puget Sound water properties are influenced by changes in ocean source waters. This metric tracks water properties on the northwest Washington shelf, presenting departures from long-term averages for temperature, salinity, dissolved oxygen, and chlorophyll. Coastal ocean changes that precede similar changes in Puget Sound are a potential indicator that source water may be driving Puget Sound variability.