The Peru/Chile upwelling system, also known as the Humboldt Current System (HCS), is the most productive region of the world oceans in terms of fisheries. It produces more fish per unit area than any other region in the world, as it represents less than 1% of the ocean surface and accounts for up to 20% of the global fishing catches. This resource is highly variable at various time scales and the societal and economical impacts of fish catches fluctuations are major. In the context of global and regional climate change (CC), it is crucial to develop and integrate scientific tools to address the impact of climate change on marine resources in this type of environment.
The goal of this project is to study and assess the impact of CC on two major fisheries in the Northern HCS (the Peruvian part of the upwelling), the sardine and anchovy. We propose to use recent global model simulations of the recent past (1958-present) and International Panel for Climate Change (IPCC) model simulations of scenarios with twice the actual CO2 concentration (hereafter “2xCO2”) to hindcast the present state and project the future changes in the regional marine environmental conditions, spawning, recruitment and biomass patterns of two targeted fisheries. To this aim, a hierarchy of dynamical, biogeochemical and biological models and statistical methods will be used to downscale the large scale climate signal from the global models to the short regional scales relevant for the pelagic fishes. In a first phase of the project, we will study the variability and validate the realism of the downscaled environmental parameters during the last decades (1958-present) using a comprehensive regional data set. This phase will be performed in collaboration with our Peruvian partners. In a second phase of the project, we will use the validated and fine-tuned models to forecast the variability of the fish-related parameters in the next hundred years under the 2xCO2 climate scenarios, using two different models IPCC models as to evaluate forecast uncertainties, and contrasted fishing effort scenarios.
During both phases, the mechanisms and feedbacks responsible for the variations will be analysed. Building from the results of previous projects that only dealt with the physical environments of the Eastern South Pacific region, this project is viewed as a great step forwards towards the constructive interaction between modellers and the communities interested in the issue of the impact of global change on the fisheries socio-economical sector. The results obtained during this project will lead to preliminary recommendations and the definition of adaptive strategies useful for society.
To achieve the proposed objectives, this project is based on the following 8 Workpackages (WPs).