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Plan-view evolution of wave-dominated deltas
(Massachusetts Institute of Technology, 2016)
Ocean waves are a powerful sediment transport mechanism in the coastal zone. This thesis investigates how waves shape deltaic landforms and how small scale river mouth processes affect large-scale delta morphology. I have ...
Decoupling of iron and phosphate in the global ocean
(Massachusetts Institute of Technology, 2003)
Iron (Fe) is an essential micronutrient for marine phytoplankton often limiting phytoplankton growth due to its low concentration in the ocean and thus playing a role in modulating the ocean's biological pump. In order to ...
Abrupt climate change in the Atlantic Ocean during the last 20,000 years : insights from multi-element analysis of benthic and planktic foraminifera and coupled OA-GCM
(Massachusetts Institute of Technology, 2005)
Minor and trace element records of planktic and benthic foraminifera from Atlantic sediment cores, as well as output from a coupled OAGCM, were used to investigate the magnitude and distribution of the oceanic response to ...
Nitrogen cycling in oxygen deficient zones : insights from [delta]¹⁵N and [delta]¹⁸O of nitrite and nitrate
(Massachusetts Institute of Technology, 2013)
The stable isotopes, [delta]¹⁵N and [delta]¹⁸O, of nitrite and nitrate can be powerful tools used to interpret nitrogen cycling in the ocean. They are particularly useful in regions of the ocean where there are multiple ...
Variations in coral reef net community calcification and aragonite saturation state on local and global scales
(Massachusetts Institute of Technology, 2013)
Predicting the response of net community calcification (NCC) to ocean acidification OA and declining aragonite saturation state [Omega]a requires a thorough understanding of controls on NCC. The diurnal control of light ...
The relationship between iron and nitrogen fixation in Trichodesmium spp.
(Massachusetts Institute of Technology, 2009)
Trichodesmium spp. are considered the dominant nitrogen (N) fixing cyanobacteria in tropical and subtropical oceans, regimes frequently characterized by low iron (Fe). Limited information exists about what levels of Fe ...
Microbial interactions associated with biofilms attached to Trichodesmium spp. and detrital particles in the ocean
(Massachusetts Institute of Technology, 2010)
Quorum sensing (QS) via acylated homoserine lactones (AHLs) was discovered in the ocean, yet little is known about its role in the ocean beyond its involvement in certain symbiotic interactions. The objectives of this ...
The biogeochemistry of marine nitrous oxide
(Massachusetts Institute of Technology, 2011)
Atmospheric nitrous oxide N₂O concentrations have been rising steadily for the past century as a result of human activities. In particular, human perturbation of the nitrogen cycle has increased the N₂O production rates ...
Seismic constraints on the processes and consequences of secondary igneous evolution of Pacific oceanic lithosphere
(Massachusetts Institute of Technology, 2016)
This thesis examines the structure of Pacific oceanic lithosphere that has been modified by post-formation magmatism in order to better understand the processes of secondary magmatic evolution of the lithosphere, which can ...
Diagnosing the variability in temperature and velocity in the Middle Atlantic Bight
(Massachusetts Institute of Technology, 2021)
Observations of hydrographic and dynamical properties on the Middle Atlantic Bight shelf document strong variability at time scales spanning events that last a few days to century long trends. This thesis studies individual ...