Marine biodiversity and the sustained exploitation of marine resources are significantly influenced by ENSO (El Niño-Southern Oscillation) particularly affecting the coastal zone of the Humboldt Current upwelling system. Both its warm (El Niño: EN) and cold (La Niña: LN) phase have drastic implications for the ecology, socio-economy and infrastructure. Local artisanal fisheries represent a major activity for the domestic economy and in consequence a huge amount of studies (published/unpublished) exists aiming at identifying effects of EN.Access to information about past states of the environment and social systems is fundamental to understand, and cope with, the challenges of climate change and over-exploitation of natural resources at the onset of the 21st century. The loss of (old) data is a major threat to understanding better and mitigating long-term effects of human activities and anthropogenic changes to the environment. Although this is intuitively evident for old and local literature of any kind, even present-day international publishing of papers without the underlying raw data makes access to basic information a crucial issue. By utilising the world data centre WDC-Mare and Pangaea (Grobe et al., 2006), the CENSOR project is filling the gap between local and ancient literature and present-day international ISI publications. We show that indeed local Grey Literature is still one of the most important sources of knowledge about natural science research and management of natural resource systems in Latin American countries adjacent to the Humboldt Current. We argue that public archiving of original data of present-day research and old (Grey) Literature and easy public access are important for appreciating todays global environmental challenges caused by human activities, both past and present, and with particular importance in the ENSO context.