Publication Date:
2022-05-26
Description:
Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution February 2017
Description:
The marine carbon cycle plays an important role in regulating Earth’s climate. The
vastness of the open ocean and the large variability in the coastal ocean provide
obstacles to accurately quantify storage and transport of inorganic carbon within marine
ecosystems and between marine and other earth systems.
Thus far, the open ocean has been the only true net sink of anthropogenic carbon
dioxide (Canthro) emissions. However, ocean storage of Canthro is not uniformly distributed.
Changes in water chemistry in the Northeast Pacific were quantified to estimate the
amount of Canthro stored in this region over the last decade. This additional Canthro was
found to cause acidification and aragonite saturation horizon shoaling at rates towards
the higher end of those found in Pacific and Atlantic Ocean basins, making the
Northeast Pacific one of the most sensitive regions to the invasion of anthropogenic
carbon dioxide.
Due to large variability in biogeochemical signals in coastal oceans, it is challenging
to accurately assess carbon fluxes across different boundaries, such as tidal exchange
between coastal wetlands and coastal oceans. Coastal salt marshes have been suggested
to be a large net CO2 sink, thus designated as a type of “blue carbon.” However, accurate
and dynamic estimates of carbon fluxes to and from tidal marshes are still premature,
particularly carbon fluxes from marshes to the coastal ocean via tidal exchange, often
referred to as marsh lateral fluxes. In this thesis, lateral total alkalinity (TA) and
dissolved inorganic carbon (DIC) export fluxes were realistically quantified using high
frequency time-series, in situ data. High-resolution fluxes permitted a closer look at how
marsh generated TA and DIC are being exported over diurnal, spring-neap, and seasonal
scales. I investigated the best way to capture variability of marsh exports via traditional
bottle sampling and assessed uncertainties associated with different sampling strategies.
Marsh TA and DIC exports significantly modified buffering capacity of coastal waters.
This work contains the first realistic estimate of TA exports from a tidal salt marsh.
Accurate estimates of DIC and TA fluxes indicate the significance of salt marshes to the
coastal carbon and alkalinity budgets.
Description:
The work in this thesis was supported by the National Science Foundation
Graduate Research Fellowship Program, Link Foundation Ocean Engineering and
Instrumentation Ph.D. Fellowship, WHOI Academic Programs Office, MIT PAOC
Houghton Fund, MIT Student Assistance Fund, WHOI Innovative Technology Award
(PI: Wang), National Institute of Science and Technologies (NIST no. 60NANB10D024,
PIs: Camilli, Wang), USGS LandCarbon Program, USGS Coastal and Marine Geology
Program, NSF (OCE-1233654, PI: Wang; OCE-1041068 PIs: Lawson, Wang, Wiebe,
Lavery; OCE-1459521 PIs: Wang, Kroeger, Gonneea), and NOAA Science Collaborative
(NA09NOS4190153, PIs: Leschen, Roth, Surgeon-Rogers, Tang, Kroeger, Ganju,
Moseman-Valtierra, Abdul-Aziz, Emmett-Mattox, Emmer, Crooks, Megonigal, Walker,
Weidman).
Keywords:
Carbon
;
Climatology
;
Metabolism
;
Salt marshes
;
Carbon dioxide
;
New Horizon (Ship) Cruise NH1208
Repository Name:
Woods Hole Open Access Server
Type:
Thesis
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