The Southeast Pacific, which encompasses the coasts of Peru and Chile, is one of the world's most productive regions resulting principally from the upwelling of subsurface nutrient-rich waters. Over the satellite altimetry era, there have been numerous evidence that surface mesoscale eddies play an important role in the offshore transport...
This study addresses the occurrence, severity, and extent of hypoxia over the continental shelf of the northern
California Current (40–48.5°N latitude) from 1998 to 2012. Clear seasonal trends exist in the timing and duration
of hypoxia. The highest bottom-water dissolved oxygen concentrations occurred from November to March, and
levels below...
A primary focus of the US Global Ocean Ecosystem Dynamics
(GLOBEC) program was to identify the mechanisms of ecosystem response to large-scale
climate forcing under the assumption that bottom-up forcing controls a large
fraction of marine ecosystem variability. At the beginning of GLOBEC, the prevailing
bottom-up forcing hypothesis was that...
The goal of the Pacific Ocean Boundary Ecosystem and Climate Study
(POBEX) was to diagnose the large-scale climate controls on regional transport
dynamics and lower trophic marine ecosystem variability in Pacific Ocean boundary
systems. An international team of collaborators shared observational and eddy-resolving
modeling data sets collected in the Northeast...
Variations in ocean conditions influenced by climate fluctuations may impact fish populations by changing their spatial distribution, physiology, survival, and other ecological features. Somatic growth is a crucial aspect of the biology of fishes and an important contributor to biomass fluctuations. Climate variability also affects somatic growth rates along the...
The commercial groundfish fishing industry and groundfish research have a long concurrent history of activity on the Oregon continental margin. Within the non-whiting groundfish fishery, the target species are primarily flatfishes, sablefish, lingcod, and rockfishes, though landings of each have fluctuated over time. Recent work shows that over the past...
Predicting recruitment, which is dependent on parent stock size and climate, is vital for forecasting productivity of fish stocks. The effects of climate can be analyzed via the use of climate indices. Three climate indices, the Pacific Decadal Oscillation, the North Pacific Gyre Oscillation, and the Oceanic Niño Index, describe...
Nearshore hypoxia within the Northern California Current (NCC) system is a seasonal phenomenon caused by coastal upwelling and occurs mainly during late-summer and early fall. The effects of low oxygen levels on fish and invertebrate communities, particularly during early-life history stages, however, are poorly known for this area. I investigated...
Changes in ocean conditions influenced by climatic fluctuations have lead to changes in individual species distributions, which alter the diversity, communities and species interactions across marine ecosystems worldwide. Assessing the species composition and identifying regions and habitats that can safeguard the persistence of biota are critically important. In this dissertation,...
Observations of the Oregon coast’s physical oceanography over the last few decades have revealed falling dissolved oxygen levels associated with seasonal upwelling, as well as rising water temperatures. In extreme cases, these changes have been associated with die-offs, redistribution, and decreased abundance and diversity of benthic fish and invertebrates. Many...
:
________________________________________________________________________
Lorenzo Ciannelli
Observations of the Oregon coast’s physical oceanography over the