Long term changes monitored in two Mediterranean Channels

The Mediterranean Sea is a mid-latitude marginal sea which has been recognised to be a climatic hotspot. During the past decade, its water masses have experienced strong and fast increases in temperature and salinity, evidencing the tendency of this area to respond very rapidly to global warming and to changes in the regional freshwater budget. Based on in situ data here it is shown where and how fast these changes occur, with a particular focus on the Western Mediterranean Deep Water and the Intermediate Water. Such trends are at least one order of magnitude higher than the global mid-latitude average trends. Indicator-type curves, routinely updated, for subsurface temperature and salinity evolution represent an outcome that is envisaged to be important for climate science, environmental agencies, concerned citizens as well as regional policy-makers.