Laser-based spectroscopic techniques, such as cavity ring-down spectroscopy (CRDS), provide a new, cost effective and more widely available approach to measure the oxygen isotope ratio in water molecules, H₂¹⁸O/H₂¹⁶O (δ¹⁸O), and are used increasingly to measure δ¹⁸O in the world's oceans. Here, we present results from an interlaboratory comparison designed...
Reconciling rates of organic carbon export from the euphotic zone with the consumption of organic material in the dark ocean remains one of the major quantitative uncertainties of the ocean carbon cycle. Euphotic zone net community production (NCP) provides one broad constraint on export flux and potential carbon drawdown. However,...
In the North Pacific Subtropical Gyre (NPSG), the regular occurrence of summer phytoplankton blooms contributes to marine ecosystem productivity and the annual carbon export. The mechanisms underlying the formation, maintenance, and decay of these blooms remain largely unknown; nitrogen fixation, episodic vertical mixing of nutrients, and meso- (<100 km) and...
Internal waves of depression were observed propagating
along‐shelf and into northern Monterey Bay, California
(CA) on the inner shelf. These waves had amplitudes
approximately equal to the thermocline depth (∼4 m), and
were unstable to shear and mix the thermocline. Isopycnal
gradient spectra showed that the wave packets lead to...
During fall/winter off the Oregon coast, oceanographic surveys are relatively scarce because of rough
weather conditions. This challenge has been overcome by the use of autonomous underwater gliders deployed
along the Newport hydrographic line (NH-Line) nearly continuously since 2006. The discharge from the
coastal rivers between northern California and the...
Patterns of primary productivity in the Arctic are expected to change with continued warming, yet productivity measurements are historically limited, both spatially and temporally. An established method of measuring net biological oxygen production, which can be used to estimate net community production (NCP) rates, is with an equilibrated inlet mass...
In this thesis, high resolution ocean models are used to evaluate and forecast coastal ocean variability in two different applications. In the first study, the 2-km resolution ocean circulation model for the Eastern Bering Sea is utilized to understand whether slope-interior exchange along the path of the Aleutian North Slope...
Moored observations are used to investigate the seasonal change in vertical structure of the cross-shelf
circulation at a midshelf location in the northern California Current System. A streamwise–normal coordinate
system is employed to eliminate meander- and eddy-induced biases in the cross-shelf flow that are unaccounted
for with an alternative, commonly...
Anthropogenic carbon dioxide (CO₂) emissions are acidifying the ocean, affecting calcification rates in pelagic organisms, and thereby modifying the oceanic carbon and alkalinity cycles. However, the responses of pelagic calcifying organisms to acidification vary widely between species, contributing uncertainty to predictions of atmospheric CO₂ and the resulting climate change. At...
The dominant processes governing ocean mixing during an active phase of the Madden–Julian oscillation are identified. Air–sea fluxes and upper-ocean currents and hydrography, measured aboard the R/V Revelle during boreal fall 2011 in the Indian Ocean at 0°, 80.5°E, are integrated by means of a large-eddy simulation (LES) to infer...