Journal Article Research Support, Non-U.S. Gov't chlorophyll 1406-65-1 AMO Chlorophyll Chlorophyll A Comparative Study Continuous Plankton Recorder NAO North Atlantic subpolar gyre Northeast Atlantic Red Sea YF5Q9EJC8Y bleaching threshold detection bottom-up processes and top-down control climate cycles conservation management tool coral bleaching marine heatwaves northern hemisphere temperature ocean colour phytoplankton decadal variability phytoplankton variability plankton climate links unexplored tropical regions