In recent decades, sea surface temperature has been increasing says a CCMAR research team that recently published a comparative study that looks at the period between 1950 and 2010. Researchers found that even in each decade and according to regions, the sea surface temperature varies and has increased from 0.1 to 0.2 degrees.

The study recently published by the team from the Centre for Marine Sciences (CCMAR) indicates that the increase in sea surface temperature was not homogeneous, varying according to the portuguese region. For example, in the South region, the increase was two times more than in the west coast.

Regional differences may be related to different factors such as wind intensity and direction, ocean currents, depth, cloudiness and intensity of coastal outcropping.

 "If we look at monthly values, these increases are even more noticeable, reaching between 0.4 and 0.5 ∘C per decade in the spring and summer, especially in the most recent decades," say Vânia Baptista and Francisco Leitão, authors of this study.

The variability of temperature and seasonality are relevant for the biology of the species, since each one can react differently to thermal stress, thus affecting its life cycle, triggering reproduction and favoring growth, for instance.

The major issue that concerns researchers is the impact of these temperature increment on phytoplankton, zooplankton and benthic communities, which belong to lower trophic levels, as this will certainly have wider ecological implications at higher levels and, consequently, fishes and fisheries.

Study available here