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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 ...
A determination of air-sea gas exchange and upper ocean biological production from five noble gasses and tritiugenic helium-3
(Massachusetts Institute of Technology, 2007)
The five noble gases (helium, neon, argon, krypton, and xenon) are biologically and chemically inert, making them ideal oceanographic tracers. Additionally, the noble gases have a wide range of solubilities and molecular ...
Radium isotopes as tracers of coastal circulation pathways in the Mid-Atlantic Blight
(Massachusetts Institute of Technology, 2003)
Pathways of exchange between the shelf and slope in the Mid-Atlantic Bight were investigated using a combination of radiochemical tracer and hydrographic measurements. The motivation was to provide evidence of transport ...
Thermally driven circulation
(Massachusetts Institute of Technology, 1987)
Several problems connected by the theme of thermal forcing are addressed herein. The main topic is the stratification and flow field resulting from imposing a specified heat flux on a fluid that is otherwise confined to a ...
The effect of a shallow low viscosity zone on mantle convection and its expression at the surface of the earth
(Massachusetts Institute of Technology, 1987)
Many features of the oceanic plates cannot be explained by conductive cooling with age. A number of these anomalies require additional convective thermal sources at depths below the plate: mid-plate swells, the evolution ...
Adaptive error estimation in linearized ocean general circulation models
(Massachusetts Institute of Technology, 1999)
Data assimilation methods, such as the Kalman filter, are routinely used in oceanography. The statistics of the model and measurement errors need to be specified a priori. In this study we address the problem of estimating ...
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 ...
Chemical characterization of dissolved organic matter (DOM) in seawater : structure, cycling, and the role of biology
(Massachusetts Institute of Technology, 2005)
The goal of this thesis is to investigate three different areas relating to the characterization of dissolved organic matter (DOM): further determination of the chemical compounds present in high molecular weight DOM ...
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 ...
The marine biogeochemistry of dissolved and colloidal iron
(Massachusetts Institute of Technology, 2013)
Iron is a redox active trace metal micronutrient essential for primary production and nitrogen acquisition in the open ocean. Dissolved iron (dFe) has extremely low concentrations in marine waters that can drive phytoplankton ...