Historic ocean seasonality and global fisheries

Rising ocean temperatures threaten marine ecosystems and food security worldwide. Yet, our current understanding of how climate change affects global marine fisheries often overlooks critical seasonal dynamics that govern ecosystem function. To address this gap, we compiled a global dataset for 187 countries between 1950 to 2018 and employed fixed effects regression to assess the effect of intra-annual sea surface temperature (SST) variation on annual marine fisheries catches. We detect a significant non-linear response with varied effects across the globe. Increases over 1°C in intra-annual SST variation estimated a 12% increase in catches for low and high latitude aseasonal countries, and a 30% decrease in catches in highly seasonal mid-latitude countries. Our analyses underscore the need to integrate ocean seasonality in efforts to better understand, mitigate and adapt to the impacts of climate change on marine fisheries, to support sustainable fisheries management as well as maintain global ocean health.