Keerthi M. G. auteur aut IRD Prend C. J. auteur aut IRD Aumont Olivier auteur aut IRD Levy Marina auteur aut IRD text journalArticle eng text/pdf born digital access Phytoplankton biomass exhibits substantial year-to-year changes, and understanding these changes is crucial to fisheries management and projecting future climate. These annual changes result partly from low-frequency climate modes that also lead to variations in sea surface temperature (SST). Here we evaluate the contribution of small scales to annual fluctuations based on a global analysis of satellite observations of sea surface chlorophyll (SChl), an indicator of phytoplankton biomass, and of SST from 1999 to 2018. We disentangle the spatio-temporal scales of variability in the time series and find that besides the prominent seasonal cycle, SChl is dominated by high-frequency fluctuations (<three months) at small spatial scales (<50 km)-which accumulates over annual scales in contrast to SST. The results suggest that observations and models with high spatio-temporal resolutions are necessary to understand annual changes in SChl. The rapid response of SChl to small-scale physical processes, combined with intrinsic ecosystem interactions and air-sea interaction feedbacks, may explain the differences between annual variations in SST and SChl. Annual variations of phytoplankton biomass can be explained by processes acting on small spatio-temporal scales, according to a global analysis of satellite observations of sea surface chlorophyll and temperature from 1999 to 2018. specialized MONDE 034 036 15 1027-1033 2022 1752-0894 https://www.documentation.ird.fr/hor/fdi:010089890 10.1038/s41561-022-01057-3 1752-0894 [F B010089890] https://www.documentation.ird.fr/hor/fdi:010089890 https://www.documentation.ird.fr/intranet/publi/2024-03/010089890.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2022-12-09 2025-02-24 fdi:010089890 fre