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El Niño Southern Oscillation (ENSO) effects on fisheries and aquaculture

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Abstract

This FAO Technical Paper synthesizes current knowledge on the impact of El Niño Southern Oscillation (ENSO) events on fisheries and aquaculture in the context of a changing climate. Fisheries and aquaculture are essential parts of the global food system. The recent discovery that ENSO is far more diverse than previously recognized highlights a pressing need to synthesize the impact of the different ENSO types on fisheries and aquaculture. The overall aim of this Technical Paper is to provide relevant, up-to-date information and help decision-makers identify the most appropriate interventions according to the diversity of ENSO types. In addition, the possible effects of climate change on these sectors can be partly illustrated by the current effects of ENSO events, which are themselves affected by climate change. The Technical Paper describes the diversity of ENSO events (Chapter 2), ENSO forecasting (Chapter 3) and ENSO in the context of climate change (Chapter 4). It includes a global overview and regional assessment of ENSO impact (Chapters 5 and 6) and a focus on coral bleaching and damage to reefs and related fisheries (Chapter 7). Finally, it synthesizes the lessons learned and the perspectives for ENSO and preparedness in a warmer ocean (Chapter 10).
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... The uncertainty about the observed impact of El Niño over the spiny lobster fishery could be associated with variations on the intensity of this climatic event. According to (Bertrand et al. 2020), no two El Niño events are alike, nor are the resulting ecological responses. ...
... In consequence, these authors have identified five ENSO events that occur at a global scale with different warming conditions. Bertrand et al. (2020) suggests that El Niño events differ on their impacts on the southeast Pacific. They found that while CP El Niño events do not significantly impact the Humboldt Current System (HCS) and related fisheries, strong and coastal El Niño events lead to warm ocean temperatures, heavy rain, floods, and heavy river discharges in northern Peru that can impact SSF infrastructure. ...
... Therefore, while extreme El Niños have the greatest impact, the response strongly differs from one event to the other, with the extreme El Niño of 1982/83 producing a much larger impact than that of 2015/16. As a result, Bertrand et al. (2020) conclude that the strength of the impact depends on the type of event. Extreme El Niños have by far the most relevant effect, followed by the EP El Niños. ...
Technical Report
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