The 2019 Marine Heatwave at Ocean Station Papa: A multi-disciplinary
assessment of ocean conditions and impacts on marine ecosystems
Abstract
In the past decade, two large marine heatwaves (MHWs) formed in the
northeast Pacific near Ocean Station Papa (OSP), one of the oldest
oceanic time series stations. Physical, biogeochemical and biological
parameters observed at OSP from 2013 to 2020 are used to assess ocean
response and potential impacts on marine life from the 2019 northeast
Pacific MHW. The 2019 MHW was preceded by calm and stratified surface
conditions, lower dissolved inorganic carbon, and higher pH of surface
waters relative to the 2013-2020 period. A spike in the summertime
chlorophyll followed by a decrease in surface macronutrients suggests
increased productivity in the well-lit stratified upper ocean during
summer 2019. More blue whale calls were recorded at OSP in 2019 compared
to the prior year. Large subsurface temperature anomalies were also
found, suggesting that the earlier northeast Pacific MHW (2013-2015,
previously referred to as “Blob”) as well as the long-term increase in
sea surface temperatures in the region contributed to the intensity of
the 2019 MHW. This study shows how the utility of long-term, continuous
oceanographic datasets and analysis with an interdisciplinary lens is
necessary to understand the potential impact of MHWs on marine
ecosystems.