Posters

Poster Session 1, Monday,  October  3, 15:40–18:00

Poster 5

Mesoscale and sub-mesoscale effects on semi-annual CHL blooms in the NE Pacific Ocean

Large summer chlorophyll (CHL) blooms spanning hundreds of square kilometers and persisting for weeks-months, are consistently observed in satellite records of the Northeast Pacific Subtropical Gyre (NPSG), at an approximate latitude of ~30°N. These blooms occur at a near annual rate, and uniquely within the late summer months of June-October. Understanding the potential impacts and biophysical drivers of these chlorophyll anomalies is both ecologically and climatologically important. These large-scale blooms can export carbon from the upper ocean to the deep ocean and fuel the productive fisheries found in the ecologically important transition zone between the North Pacific Subtropical Gyre and the subpolar gyre. The purpose of this project is to characterize CHL blooms in the NE Pacific Gyre, as well as describe their association with (sub)mesoscale features to identity potential physical drivers. First, an analysis of the merged satellite CHL product is done to characterize the magnitude and frequency of CHL blooms in the NPSG. Then, a cluster analysis is applied to the CHL anomalies that occur in the NPSG encompassing the canonical 30°N blooms and at the Hawaii Ocean Time-series (HOT) Station ALOHA. The cluster analysis is intended to determine the association of (sub)mesoscale regions with CHL blooms. Through this process, we hope to provide a statistically driven characterization of CHL anomalies in the NPSG. Further analyses present case-study time-series of a bloom in order to better understand the time-resolved change in phytoplankton biomass and how it relates to physical drivers of biomass growth and accumulation.

*James Ash, University of Hawaii at Manoa, [email protected]

Angel White, University of Hawaii at Maona, [email protected]