Observed and modeled bio-optical, bioluminescent, and physical properties during a coastal upwelling event in Monterey Bay, California

Abstract

[1] During spring and summer time, coastal upwelling influences circulation and ecosystem dynamics of the Monterey Bay, California, which is recognized as a National Marine Sanctuary. Observations of physical, bio-optical properties (including bioluminescence) together with results from dynamical biochemical and bioluminescence models are used to interpret the development of the upwelling event during August 2003 in Monterey Bay, California. Observations and the biochemical model show the development of a phytoplankton bloom in the southern portion of Monterey Bay. Model results show an increase of nutrients in the southern portion of the bay, where nutrient-rich water masses are brought in by the southward flow and cyclonic circulation inside the bay. This increase in nutrients together with the sluggish circulation in the southern portion of the bay provides favorable conditions for phytoplankton growth. Our observations and models suggest that with the development of upwelling the offshore water masses with the subsurface layer of bioluminescent zooplankton were replaced by water masses advected from the northern coast of the bay with a relatively high presence of mostly nonbioluminescent phytoplankton. Inshore observations from autonomous underwater vehicles (AUVs) show consistent coincidence of chlorophyll, backscatter, and bioluminescence maxima during upwelling development. Offshore AUV observations (taken at the entrance to the bay) show a deeper bioluminescence maximum below the surface layers of high chlorophyll and backscatter values during the earlier stages of upwelling development. Later, the observed deep offshore bioluminescence maximum disappeared and became a shallower and much weaker signal, coinciding with high chlorophyll and backscatter values offshore. Based on the biochemical and bioluminescence models, a methodology for estimating the nighttime water-leaving radiance due to stimulated bioluminescence is demonstrated and evaluated.

Can vertical migrations of dinoflagellates explain observed bioluminescence patterns during an upwelling event in Monterey Bay, California?

“…Non‐bioluminescent phytoplankton were advected. Results from the dynamical bioluminescence model showed high values of bioluminescence intensity (BL) along the entrance to the Bay [ Shulman et al , 2011], which was not in agreement with the observed BL. In the model, the BL dynamics were controlled by advective and diffusive processes only, and as it was speculated by Shulman et al [2011], the lack of modeling of behavioral dynamics of bioluminescent organisms, as well as modeling of growth and loss terms, are responsible for the BL model's inability to predict the observed weakening of the BL intensity along the entrance to the Bay.…”

Bio‐Optical Data Assimilation With Observational Error Covariance Derived From an Ensemble of Satellite Images

“…The Monterey Bay model (see domain in Figure ) consists of a physical model, which is coupled to a biochemical model (Shulman et al, ). The physical model of the Monterey Bay is based on the NCOM model, which is a primitive‐equation, 3‐D, hydrostatic model.…”

Microalgae: Current Research and Applications

“…Meanwhile, in the field, bioluminescence has been used to study ecological dynamics within the plankton and to monitor toxic blooms (Moline et al, 2009;Shulman et al, 2011;Le Tortorec et al, 2013). Studies on dinoflagellate bioluminescence have shed like on fundamental processes like cellular mechanotransduction (von Dassow & Latz, 2002;Chen et al, 2007;Jin et al, 2013), circadian rhythms (Hastings, 2009) and evolution of gene structure (Liu et al, 2004;Liu & Hastings, 2007).…”