The timing of the formation of the Isthmus of Panama and the consequent isolation of the Caribbean Sea from the tropical eastern Pacific (TEP) have long been of fundamental interest to geologists, biologists, and oceanographers, yet there remain many questions regarding the paleoclimate, paleogeography and the timing of the uplift of the Isthmus. Presently, the Isthmus strongly determines the marine oceanic environmental condition of the TEP. Three independent lines of evidence based on past studies are consistent about abundant seawater exchange between the oceans until about 4.2–3.5 Ma: 1) North and South American terrestrial mammals and tropical forest bird faunas remained overwhelmingly isolated until about 2.5 Ma; 2) Isotopic and sedimentary data from ocean cores demonstrate that divergence in surface salinity and deep-sea carbonate accumulation between the Caribbean and eastern Pacific did not occur until 4.7–4.2 Ma; and (3) Bathyal foraminifera first diverged across the developing Isthmus approximately 13 Ma, but numerous mollusks and cheilostomes are known from both oceans until the Middle Pliocene. The dynamics of upwelling on both sides of the Isthmus before and after the Isthmus uplift are still inconclusive. Here, we are interested to propose a session on upwelling pattern and climate of the tropical eastern Pacific ocean using a thick sequence of deposits in the Burica Peninsula (Costa Rica/Panama boundary) that span the last 5 My. Terrestrial (paleovegetation), paleoceanographic (paleoelevation, dinoflagellates cysts), and geochemistry (C/N ratio) record will also be required as well.