Oceanic time series have been instrumental in providing an understanding of biological, physical, and chemical dynamics in the oceans and how these processes change over time. However, the extrapolation of these results to larger oceanographic regions requires an understanding and characterization of local versus regional drivers of variability. Here we use high-frequency spatial and temporal glider data to quantify variability at the coastal San Pedro Ocean Time-series (SPOT) site in the San Pedro Channel (SPC) and provide insight into the underlying oceanographic dynamics for the site. The dataset could be described by a combination of four water column profile types that typified active upwelling, a surface bloom, warm-stratified low-nutrient conditions, and a subsurface chlorophyll maximum. On weekly timescales, the SPOT station was on average representative of 64% of profiles taken within the SPC. In general, shifts in water column profile characteristics at SPOT were also observed across the entire channel. On average, waters across the SPC were most similar to offshore profiles, suggesting that SPOT time series data would be more impacted by regional changes in circulation than local coastal events. These results indicate that high-resolution in situ glider deployments can be used to quantify major modes of variability and provide context for interpreting time series data, allowing for broader application of these datasets and greater integration into modeling efforts.
Bibliographical noteKAUST Repository Item: Exported on 2020-04-23
Acknowledgements: This work was funded by NOAA ECOHAB, NSF-ChemOce (1260296 to Maria Prokopenko and 1260692 to Dough Hammond), NSF-OCE 1323319, the University of Southern California, a USC Provost Fellowship, the NSF graduate research fellowship program, the Wrigley Institute for Environmental Sciences, and the King Abdullah University of Science and Technology. We would like to acknowledge the help of Carl Oberg, Nick Rollins, Alyssa Gellene, Ivona Cetinic, Arvind Pereira, Ray Arntz, Kyaa Heller, Dario Diehl, Troy Gunderson, Diane Kim, the Fuhrman lab, the Sukhatme lab, the Caron lab, the Southern California Coastal Water Research Project, the crew of the RV Yellowfin, and many others at USC who helped with SPOT data collection and with glider deployment, recovery, and maintenance. We would also like to acknowledge the constructive feedback of the two anonymous referees.