Revista de Biología Tropical Vol.64 (suppl. 1)
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Ítem Euphausiids (Crustacea: Euphausiacea) from a hotspot of marine biodiversity, Isla del Coco, Costa Rica, Eastern Tropical Pacific(2016) Azofeifa Solano, Juan Carlos; Corrales Ugalde, Marco; Castellanos Osorio, Iván; Morales Ramírez, ÁlvaroEuphausiids have been well studied in several regions of the Pacific Ocean; however, there is less information regarding euphausiids in Costa Rican waters. We analyzed euphausiid specimens collected around Isla del Coco National Park during 2011 and 2012. A total of 130 specimens were analyzed and 13 euphausiid species were identified, belonging to four genera and one family. An annotated list of species is presented, with photographs and details for their identification. All species found represent new records for waters around Isla del Coco in the Costa Rican Pacific. The most frequent species were Euphausia diomedeae, Euphausia distinguenda, Nematoscelis gracilis and Stylocheiron affine.Ítem Climate of an oceanic island in the Eastern Pacific: Isla del Coco, Costa Rica, Central America(Universidad de Costa Rica) Alfaro Martínez, Eric J.; Hidalgo León, Hugo G.Studies of atmosphere-ocean interaction in the Pacific of Costa Rican are scarce. To identify oceanographic systems that may be influencing climate near Cocos Island (Eastern Tropical Pacific Seascape) we conducted six scientific expeditions between 2007 and 2012. Two automated weather stations were set near Chatham and Wafer bays during the expeditions. Data included records from National Meteorological Institute, Global Precipitation Climatology Project (GPCP) and Extended Reconstructed Sea Surface Temperature (ERSST). The climate is typical of the Eastern Tropical Pacific. Its seasonality is driven by precipitation variability associated with meridional migration of the Intertropical Convergence Zone. The seasonal cycle has two peaks, in May and July, a relative minimum between them in June, and the absolute minimum in February. Most of the precipitation is recorded from April to November. Most rain events have short duration and low intensity. An SST trend was observed from January 1854 to December 2013, coherent with regional warming temperature observations. From 1998 to 2013 there were changes in distributions of almost all meteorological parameters. The combination of these factors resulted in higher evapotranspiration values through the daily cycle, especially during the night time. Precipitation (P) positive anomalies tended to be associated with positive air surface temperature (AST) and SST anomalies and negative global radiation (GR) anomalies. Negative P anomalies tended to be associated with negative AST, SST and positive GR anomalies. Relative humidity (RH) negative anomalies tend to be associated with positive wind speed (WS) anomalies, and the WS effect is opposite for positive RH anomalies. During the cold Niño 3 condition of October 2007, negative P, AST, SST and RH anomalies were observed in concordance with positive WS and GR anomalies, in agreement with the conceptual model of climate system response at Isla del Coco to cold ENSO conditions.