General Description and Scientific Significance

The EPIC (Eastern Pacific International Cruise) expedition, conducted between January and March 2019 aboard the research vessel R/V Mirai of the Japan Agency for Marine-Earth Science and Technology (JAMSTEC), aimed to investigate the physical, chemical, and biological processes that regulate the functioning of the Southeastern Pacific Ocean, from the Chilean coast to the central Pacific. The expedition followed a transect extending from the Valparaíso Region toward the Atacama Trench, continuing to the Desventuradas Islands, Rapa Nui (Easter Island), and concluding in Tahiti.

The expedition brought together researchers from Chile, Japan, and other international institutions to study the interactions among surface biological productivity, marine microbiology, biogeochemistry, and ocean circulation. A particular focus was to understand the processes responsible for the uptake of atmospheric carbon dioxide (CO₂) and its transport into the deep ocean, providing key information for understanding the ocean's role in regulating the global climate.

The Millennium Institute of Oceanography (IMO) participated alongside researchers from the Pontifical Catholic University of Valparaíso and the Catholic University of the North, contributing scientific equipment and expertise in marine microbiology, biogeochemistry, and plankton research. The expedition strengthened scientific cooperation between Chile and Japan and further consolidated IMO's participation in large-scale international oceanographic research programs.

 

Scientific Objectives

• Study the physical, chemical, and biological conditions of the surface and deep Pacific Ocean. 
• Investigate the biogeochemical processes controlling the uptake and transport of atmospheric CO₂ into the deep ocean.₂ desde la atmósfera hacia el océano profundo. 
• Characterize marine microbial communities across different environments of the Southeastern Pacific.
• Analyze the distribution of phytoplankton, zooplankton, and other components of the planktonic community.
• Strengthen international scientific collaboration between Chilean institutions and JAMSTEC.

Onboard Technology

• R/V Mirai research vessel (JAMSTEC).
• WP-2 Net for zooplankton sampling.
• Agassiz trawl for collecting benthic organisms.
• ORP-pH sensors and instrumentation for measuring pH and oxidation-reduction potential (ORP).
• Equipment for seawater sampling and biogeochemical analyses provided by Chilean institutions.

Participating Institutions

• Japan Agency for Marine-Earth Science and Technology (JAMSTEC)
• Millennium Institute of Oceanography (IMO)
• Pontifical Catholic University of Valparaíso (PUCV)
• Catholic University of the North (UCN)