Spring 2017 Ocean Sciences Seminar
Spring 2017 Seminars
A-340 Earth & Marine Sciences Building
Fridays, 10:40 a.m. - 11:45 a.m. (unless otherwise noted)
Seminar Coordinator: Phoebe Lam email@example.com
For disability-related accommodations: call (831) 459-4730 or email firstname.lastname@example.org
Piero Mazzini, Assistant Professor, Romberg Tiburon Center for Environmental Studies
**Special Location E&MS D250
**Host Chris Edwards
The Combined Effect of River Discharge and Wind Forcing in the Coastal Ocean
Freshwater provided from river discharge influences the dynamics and circulation of most continental shelves around the world. It has profound effects on the transport and fate of materials and substances originated from rivers and estuaries, as well as on the ocean biogeochemistry and marine ecosystems. The effect of buoyancy forcing and its modification by windstress off the Oregon coast are studied here, with an emphasis on the downwelling season (fall/winter). Six years of underwater glider data are used in this study, from 2006 to 2012, bringing unprecedented high-resolution view of the downwelling season, allowing for the first time, the characterization of the Oregon Coastal Current.
Claudie Beaulieu, Asst. Professor, Ocean & Earth Science, Univ. of Southampton
Detection of Climate and Oceanographic Change in the Big Data Era
Natural variability in all aspects of the Earth system – including the climate system and ecosystems – presents a formidable challenge to the detection and quantification of change forced by industrial activities. Error in detection can disrupt concerted efforts to respond to the challenges of Earth system change, whereas statistically robust quantification informs our understanding of underlying mechanisms of change and helps to improve predictions into the future. The rate of observed climate change results from the superposition of natural and anthropogenic forcing and its robust estimation needs to objectively detect the timing of changes in the trend as well as their magnitude. Quantifying the rate of climate change is further challenged by “memory” within the climate system, which can lead to overconfidence in the detected change. In this talk, I describe a new approach to separate unsteady long-term change from memory, which clarifies a key point in the scientific debate related to the recent “hiatus” in warming.
Marine ecosystems may also respond to climate change, but detecting these impacts is hindered by the long timescale of memory within the ocean such that time-series analysis of satellite data is still inconclusive as to the sign of change in ocean chlorophyll. Here I show how utilizing both temporal and spatial dependency in the available data reveals the full uncertainty in chlorophyll trends and highlights regions undergoing significant change. More generally, the targeted development of specific statistical techniques is required to process and make full use of the rapidly growing store of Earth system data from models and advancing observational platforms. Space-time modeling in particular is one of my main research directions for the promise it holds to improve detection of climate and oceanographic change in the era of big data.
Jed Fuhrman, Professor, University of Southern California
*Host: Marilou Sison-Mangus
A Long Term Perspective on Recent Advances in Marine Microbial Ecology
Over 35 years ago it was discovered that marine bacteria process about half of all the total marine primary productivity (or about a quarter of global productivity) via their uptake of dissolved organic matter and the “microbial loop.” There have been many discoveries since then (often by molecular genetic techniques), including the importance of marine viruses, multiple varieties of non-“extremophile” archaea that sometimes exceed bacteria in abundance locally, incredibly diverse picoplanktonic photoautotrophs, mixotrophs, ubiquitous rhodopsins for solar energy capture, and much more. I’ll briefly go over these historic discoveries and discuss recent work in my lab on seasonality and predictability of microbial populations and its interpretation, surprisingly rapid community changes during and after the spring bloom, the significance of microdiversity, and the need to use standards like “mock communities” in all microbiome analyses.
Kelly Benoit-Bird, Senior Scientist, Monterey Bay Aquarium Research Institute
Resolving the Food Paradox in the Sea
The average concentrations of biota in the ocean are generally low, a critical problem for ocean consumers. When we examine the biology with new tools guided by the predators themselves, we find that instead of being relatively devoid of life, the ocean is peppered with narrow hot-spots of activity. Small patches of plenty have impacts on ecosystems disproportionate to their contribution to the total biomass, providing the key to solving the experimentally demonstrated feeding paradox as well providing a mechanism for evolution in an apparently isotropic environment where there are no obvious barriers to gene flow, Hutchinson’s “Paradox of Plankton”
Yui Takeshita, Scientist, Monterey Bay Aquarium Research InstituteTowards sustained autonomous measurements of net community production and calcification on coral reefsNet community production and calcification are fundamental ecosystem properties of coral reefs, yet understanding of the drivers of these key processes is hindered by the lack of methodology to make sustained observations with sufficient temporal resolution. In this talk, I will describe the development of the Benthic Ecosystem and Acidification Measurement System (BEAMS), an autonomous system that is capable of simultaneously measuring benthic net community production and calcification for weeks at 15 minute intervals.
Colleen Durkin, Research Faculty, Moss Landing Marine LaboratoryLinking phytoplankton with sinking particles and carbon exportWhen phytoplankton are transported out of the surface ocean they sequester carbon from contact with the atmosphere and fuel deep sea food webs. This talk will explore the consequences of plankton composition and physiology on carbon export and the mechanisms that lead to vertical transport. Integrating molecular and particle imaging approaches enables resolution of carbon export processes from the upper ocean all the way to the deep seafloor.
Isabel Reche Cañabate, Professor, Universidad de Granada
Colleen Hansel, Associate Scientist, Woods Hole Oceanographic Institution
Jim Cloern, Senior Research Scientist, USGSPatterns and Processes of Ecosystem Variability in Estuaries: Lessons from Long-term Study of San Francisco Bay
Andrea Fassbender, Scientist, Monterey Bay Aquarium Research Institute