Observed and projected sea surface temperature seasonal changes in the Western English Channel from satellite data and CMIP5 multi-model ensemble

摘要: Seasonal Sea Surface Temperature (SST) changes in the Western English Channel have been estimated for previous decades from high-resolution satellite data. Coastal seas, well separated offshore waters by intense frontal structures, show colder SST 1 to 2°C summer. A significant warming trend is observed autumn season. This positive stronger offshore, with an annual mean increase of 0.32°C/decade, but weaker coastal (0.23°C/decade), where strong vertical mixing induced tides and winds acts reduce surface warming. The performance ensemble CMIP5 climate model simulating recent seasonal region estimated. median models reproduces very cycle less proficient sector due coarse resolution absence tidal forcing related processes. In Iroise Sea, a biological activity located off western tip Brittany, relatively simulated, albeit somewhat underestimated (0.20°/decade) evenly distributed throughout year. Here, future scenarios simulations ranges 0.5°C (RCP2.6) 2.5°C (RCP8.5) year 2100, modulation leading more summer than winter. may strongly affect marine biology, particularly phytoplankton phenology, macro-algae biomass benthic fauna, including exploited shellfish, Channel.