Changing oceans and coasts: Where's our early warning system?

Climate change is already impacting U.S. marine/coastal ecosystems and the communities that depend on them.   These impacts are expected to significantly increase with continued changes in the global climate system.  The ability to track and provide early-warnings of climate-related changes in these systems is weak (mostly indicators of physical changes).  Few indicators are currently available to assess biological or social/economic impacts.  With support, some existing observations could provide much needed indicators in these areas.  Decision-makers need a better indicators to reduce impacts and increase resilience of U.S. marine and coastal ecosystems.