Skip to main content

M.E. Hansen

thumbnail
A user-friendly, stand-alone application for the calculation of carbonate system parameters was developed by the U.S. Geological Survey Florida Shelf Ecosystems Response to Climate Change Project in response to its Ocean Acidification Task. The application, by Mark Hansen and Lisa Robbins, USGS St. Petersburg, FL, Joanie Kleypas, NCAR, Boulder, CO, and Stephan Meylan, Jacobs Technology, St. Petersburg, FL, is intended as a follow-on to CO2SYS, originally developed by Lewis and Wallace (1998) and later modified for Microsoft Excel? by Denis Pierrot (Pierrot and others, 2006). Besides eliminating the need for using Microsoft Excel on the host system, CO2calc offers several improvements on CO2SYS, including: An improved...
Categories: Publication; Types: Citation; Tags: Open-File Report
thumbnail
This paper summarizes the results of a comparative bathymetric study encompassing 150 km of the Louisiana barrier-island coast. Bathymetric data surrounding the islands and extending to 12 m water depth were processed from three survey periods: the 1880s, the 1930s, and the 1980s. Digital comparisons between surveys show large-scale, coherent patterns of sea-floor erosion and accretion related to the rapid erosion and disintegration of the islands. Analysis of the sea-floor data reveals two primary processes driving this change: massive longshore transport, in the littoral zone and at shoreface depths; and increased sediment storage in ebb-tidal deltas. Relative sea-level rise, although extraordinarily high in the...
Categories: Publication; Types: Citation; Tags: Journal of Coastal Research
thumbnail
The role of relative sea-level rise as a cause for the rapid erosion of Louisiana's barrier island coast is investigated through a numerical implementation of a modified Bruun rule that accounts for the low percentage of sand-sized sediment in the eroding Louisiana shoreface. Shore-normal profiles from 150 km of coastline west of the Mississippi delta are derived from bathymetric surveys conducted during the 1880s. 1930s and 1980s. An RMS difference criterion is employed to test whether an equilibrium profile form is maintained between survey years. Only about half the studied profiles meet the equilibrium Criterion this represents a significant limitation on the potential applicability of the Bruun rule. The profiles...
Categories: Publication; Types: Citation; Tags: Marine Geology
View more...
ScienceBase brings together the best information it can find about USGS researchers and offices to show connections to publications, projects, and data. We are still working to improve this process and information is by no means complete. If you don't see everything you know is associated with you, a colleague, or your office, please be patient while we work to connect the dots. Feel free to contact sciencebase@usgs.gov.