A5007445340- Marine and coastal ecosystems
- Ocean Acidification Effects and Responses
- Oceanographic and Atmospheric Processes
- Marine Biology and Ecology Research
- Marine Bivalve and Aquaculture Studies
- Marine and fisheries research
- Atmospheric and Environmental Gas Dynamics
- Marine and environmental studies
- Coral and Marine Ecosystems Studies
- Climate variability and models
- Methane Hydrates and Related Phenomena
- Geology and Paleoclimatology Research
- Isotope Analysis in Ecology
- Atmospheric chemistry and aerosols
- Aeolian processes and effects
- Food Industry and Aquatic Biology
- Biocrusts and Microbial Ecology
- Geological formations and processes
- Soil Carbon and Nitrogen Dynamics
- Arctic and Antarctic ice dynamics
- Geomagnetism and Paleomagnetism Studies
- Hydrocarbon exploration and reservoir analysis
- Wastewater Treatment and Nitrogen Removal
- Coastal and Marine Dynamics
- Geological Studies and Exploration
University of Victoria
2009-2025
Fisheries and Oceans Canada
2016-2025
Simon Fraser University
2013-2024
University of British Columbia
2002-2023
NOAA Pacific Marine Environmental Laboratory
2008
National Oceanic and Atmospheric Administration
2008
Universidad Autónoma de Baja California
2008
Oregon State University
2008
Texas A&M University
2004
The absorption of atmospheric carbon dioxide (CO2) into the ocean lowers pH waters. This so-called acidification could have important consequences for marine ecosystems. To better understand extent this in coastal waters, we conducted hydrographic surveys along continental shelf western North America from central Canada to northern Mexico. We observed seawater that is undersaturated with respect aragonite upwelling onto large portions shelf, reaching depths approximately 40 120 meters most...
As the oceans absorb anthropogenic CO2 they become more acidic, a problem termed ocean acidification (OA). Since this increase in is occurring rapidly, OA may have profound implications for marine ecosystems. In temperate northeast Pacific, fisheries play key economic and cultural roles provide significant employment, especially rural areas. British Columbia (BC), sport (recreational) fishing generates income than commercial (including expanding aquaculture industry). Salmon (fished...
Abstract The ocean absorbs anthropogenic carbon, slowing atmospheric CO 2 increase but driving acidification. Long‐term changes in the carbon system are typically assessed from single‐point time series or hydrographic sections spaced by decades. Using higher resolution observations (1–3 year −1 ) Line P series, we investigate processes modulating trends of northeast subarctic Pacific. Dissolved inorganic (DIC) and apparent oxygen utilization (AOU) 1990 to 2019 reveal substantial over most...
Abstract Estuarine systems host a rich diversity of marine life that is vulnerable to changes in ocean chemistry due addition anthropogenic carbon. However, the detection and impact secular carbon trends these complicated by heightened natural variability as compared open‐ocean regimes. We investigate biogeochemical between pre‐industrial (PI) modern periods using high‐resolution, three‐dimensional, biophysical model Salish Sea, representative Northeast Pacific coastal system. While seasonal...
Abstract The Strait of Georgia (SoG) is a large semienclosed estuary that spatially dominates the Salish Sea on North American Pacific coast. region well populated, harbors significant aquaculture, and vulnerable to climate change. We present first inorganic carbon data collected in SoG covering all seasons (2003 2010–2012) put them into context local circulation oxygen cycles. Results show has higher content lower pH than surrounding waters. Aragonite saturation horizons do not become...
Under physically isolated conditions, net community production (NCP) can be accurately estimated from the rate of oxygen evasion to atmosphere derived local mixed layer oxygen/argon measurements. We use a simple box model demonstrate that, when physical inputs are negligible, sea‐to‐air flux biological (bioflux) represents average NCP exponentially weighted over past several residence times in layer. This new weighting scheme shows that there is no apparent lag between bioflux and...
Abstract We present a coupled three‐dimensional biological‐physical model for the Salish Sea and evaluate it by comparison to nitrate, silicate, chlorophyll observations. It accurately reproduces nitrate concentrations with Willmott skill scores, root‐mean‐square error, bias ranging from 0.84–0.95, 4.02–6.5 μM, −2.33–1.84 respectively, compared three independent discrete sample data sets. A prominent feature of output is tidal jet emanating Discovery Passage producing downstream plume...
Abstract Ocean warming and deoxygenation are already modifying the habitats of many aerobic organisms. Benthic habitat in Northeast Pacific is sensitive to deoxygenation, as low oxygen concentrations occur naturally continental shelf bottom waters. Here, we examine potential impacts ocean on distribution halibut ( Hippoglossus stenolepis ), one most commercially important groundfish North America. We combine fisheries‐independent survey data (1998–2020) with oceanographic measurements a...
Abstract The waters over the southern Vancouver Island shelf and slope are productive, economically important regions. circulation is highly dynamic through variable mixing of both younger subarctic older water masses, significant local upwelling downwelling regimes. We take advantage three time series that cover more than decades: La‐Perouse, Line‐P, CalCOFI series, each covering at least 37 years (1984–2021). investigate subsurface salinity, temperature, depth observations to study...
The distribution of dissolved (<0.4 μ m) iron (Fe) across the continental shelf and slope Queen Charlotte Sound on west coast Canada was examined to estimate potential these waters as a source Fe Fe‐limited subarctic northeast Pacific. Iron profiles obtained in shelf, slope, offshore demonstrate decreasing concentrations with distance from continent. Within 50 m sediments were 5.3 ± 0.3 nM. This signal detected, although attenuated by 80%, along isopycnal surface at stations 40–50 km...
Anthropogenic climate change is causing our oceans to lose oxygen and become more acidic at an unprecedented rate, threatening marine ecosystems their associated animals. In deep-sea environments, where conditions have typically changed over geological timescales, the animals, adapted these stable conditions, are expected be highly vulnerable any or direct human impact. Our study coalesces one of longest observational oceanographic time series, reaching back 1960s, with a modern visual...
Abstract We measured the carbonate system (between 2015 and 2018) in an isolated a well‐connected temperate estuary, both known for shellfish growth. evaluated end‐member model estimates of inorganic carbon, alkalinity, pH, mineral saturation states (Ω ), pH sensitivity (βDIC). find winter conditions are estimated within observational uncertainty. Spring‐summer primary productivity elevates observed Ω above theoretical lines, beyond Both estuaries sensitive likely to experience rapid changes...
Coastal upwelling regions are associated with high primary production and disproportionately large fluxes of organic matter relative to the global ocean. However, coastal usually homogenized in ocean carbon models. We have developed a nitrogen flux model including all major processes both within below euphotic zone over seasonal decadal timescales for regions. These control surface p CO 2 . The is applied west coast Vancouver Island, Canada (∼49°N, 126°W). Net annual air‐sea exchange export...
We present continuous, high‐resolution measurements of surface dimethylsulfide (DMS), p CO 2 , and O /Ar obtained in coastal waters off British Columbia, Canada, using membrane inlet mass spectrometry (MIMS). Sampled underway at a frequency twice per minute (every ∼160 m 10 knots cruising speed), our data reveal fine‐scale structure gas variability its covariance with number hydrographic parameters. All parameters exhibited large ranges ( 200–747 ppm; DMS, <1–29 nM; chl <0.1–33 μ g L...
Abstract Concentrations of dimethylsulfide (DMS), measured in the Subarctic Pacific during summer 2010 and 2011, ranged from ∼1 to 40 nM, while dissolved dimethylsulfoxide (DMSO) concentrations (range 13‐23 nM) exceeded those dimethyl sulfoniopropionate (DMSP) 1.3–8.8 nM). Particulate DMSP dominated reduced sulfur pool, reaching maximum 100 nM. Coastal off shore waters exhibited similar overall DMS concentration ranges, but sea‐air fluxes were lower oceanic due wind speeds. Surface showed...
The timing, duration, and intensity of wind‐driven upwelling downwelling along the North American Pacific coast play an integral role in coastal circulation basinwide ecosystem composition. It has been suggested that global warming will cause changes these winds. Here we develop a new set objective criteria to unambiguously determine onset, seasons due local wind forcing. We use examine better characterize temporal trends currents over previous 60 years relate them large‐scale climate...
Abstract Declines in mean ocean pH and aragonite saturation state (Ω A ) driven by anthropogenic CO 2 emissions have raised concerns regarding the trends of Ω estuaries. Low can be harmful to a variety marine organisms, especially those with calcium carbonate shells, so may threaten productive ecosystems commercial fisheries found many estuarine environments. The Strait Georgia is large, temperate, system numerous wild aquaculture shellfish finfish populations. We determine seasonality...
Recently, independent concerns about declining oxygen and pH conditions in the coastal ocean have emerged. In upwelling regions, hypoxia can be driven by onshore advection of oxygen‐depleted offshore waters as well local biological consumption triggered high productivity. As both mechanisms also decrease carbonate saturation states, coupled studies carbon are imperative. A quasi two‐dimensional model coupling carbon, oxygen, nitrogen was developed for summer wind‐driven region off southern...
† OA here refers to a second carbon parameter (i.e.pH, DIC, or TA) that will make the sensor package capable of reflecting ocean acidification conditions.‡ This observational system be part cabled observatory node.§ station is an