2010 summer snapshot of warm eddy in Canada Basin, Arctic Ocean

Abstract

Using the icebreaker R/V Araon, the first Arctic scientific cruise has been conducted with the multi-disciplinary purposes between July and August, 2010. Intensive physical (hydrographic) and biochemical survey data were collected from 38 stations along the Northwind Ridge (NwR) and the vicinity of western Canada Basin (CB). By analyzing the CTD castings, the warm water passing through the Bering Strait was extensively identified in the depth of ca. 30-150 m, forming the strong warm eddies. In particular, warm eddies were predominantly found near the peak of NwR and the continental slope of CB. The nutrient distribution and chlorophyll-a concentration generally matched with the location of warm eddies. Nitrate was the limiting factor of phytoplankton growth, and generally small-sized cells were mostly dominated. However, warm eddy area was characterized by large-sized cells (e.g., diatom). During the presentation, the spatial variability in specific water masses determined by temperature and salinity will be discussed by linking with the distribution of nutrient and plankton biomass. Moreover, microscopic observation and pigment analysis for phytoplankton community study will be discussed.