Summer 2021 Low Oxygen Event on the West Coast of North America

Adapted and condensed by OOI from Tetjana et al., 2022. 

A team of researchers using OOI Coastal Endurance data reported a low oxygen event on the west coast of America. They found that while hypoxic events are known to occur seasonally in coastal bottom waters along the west coast of North America, 2021 was more severely hypoxic. The onset of low oxygen water was the earliest in 35 years (NOAA, 2021), lasted longer (Lundeberg, 2021), was anomalously low, and covered a larger extent, reaching north into Canadian waters where hypoxia is rare (Crawford and Pe.a, 2013).

Dissolved oxygen measured from an underwater vehicle glider operated by Oregon State University on a cross-shore transect off Grays Harbor, Washington, USA (plots available at http://nvs.nanoos.org and data available at the U.S. Integrated Ocean Observing System Glider Data Acquisition Center, http://gliders.ioos.us ). Hypoxic water occupies the lower three-quarters of the water column near the mid-shelf mooring location (~80 m isobath) and stretches from the outer continental shelf, shoreward to at least the 50-m isobath.

The paper was published in the Winter 2022 edition of Pices Press and can be reviewed here.