QUEST is a global programme, thus defining the scale of interest to QUEST-Fish. However it would presently be unrealistic to undertake a study of the entire world fish production system in the 30 months planned under this project. In addition, the POLGCOMS project will not be completed at the start of QUEST-Fish, and thus QUEST-FISH will initially use preliminarily model setups from GCOMS (currently available) and develop along side the last 18 months of that project.

The geographical unit of QUEST-Fish will be based on the Large Marine Ecosystem (LME) concept. LMEs are regions of ocean space encompassing coastal areas from river basins and estuaries to the seaward boundaries of continental shelves and the outer margins of the major current systems. They are relatively large regions characterized by distinct bathymetry, hydrography, productivity, and trophically dependent populations. Since the early 1990s the Global Environmental Facility (GEF) and its implementing agencies (World bank, UNDP, FAO, UNEP) have used the LME as a framework to study, protect and restore marine ecosystems. Through discussions with the GCOMS project, QUEST-Fish selected a total of 21 LMEs (equivalent to 14 GCOMS domains), see table below.

Potential fish production estimates will be computed for these areas, for four fixed temporal scenarios: pre-industrial (1800), present (2005), and future (2050 and 2100). For each scenaria we will run 3 ensembles, so that both the climate variability and the climate change signals are captured. For each scenario we will have 5 years of data. In order to estimate impacts and vulnerabilities for human societies of the production scenarios developed, figures for LMEs will be downscaled to the national countries in each LME. This spatial and temporal simplification of the problem, and geographical downscaling, will ensure that QUEST-Fish will deliver its objective in the time and resources allocated.

Nevertheless, QUEST-Fish recognises the importance of globalisation, and the need to look at fish production not only at LME and national level but globally. For this purpose we will investigate the global and local consequences of fluctuations in small pelagic fish production, and thus on the production of fishmeal, under Modules 3 and 4. Fishmeal is a high protein feedstuff used extensively in the aquaculture and animal industries. It is a global commodity traded freely in the international market that has seen unprecedented increases in demand and price in recent years as a result of aquaculture development. Some 80% of the global supply is from the Humboldt Current, and is very susceptible to the frequency of El Niño events and multi-decadal climate cycles. The impacts of fluctuations in fishmeal are felt regionally, nationally and locally, allowing us to estimate the vulnerabilities of this global, climate-driven trade, at different scales.