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Temporal Variability Of Satellite-Derived Chlorophyll And Sea Suface Temperature In The California Current, Kasey Legaard Dec 2004

Temporal Variability Of Satellite-Derived Chlorophyll And Sea Suface Temperature In The California Current, Kasey Legaard

Electronic Theses and Dissertations

Physical forcing and biological response within the California Current coastal upwelling system are highly variable over a wide range of scales. Satellite remote sensing offers the only feasible means of quantifying this variability over the full extent of this current system. Here we quantify and compare patterns of physical and biological variability acting over seasonal, interannual and dominant intraseasonal time scales throughout the California Current System using more than five years (1997-2003) of daily SeaWiFS chlorophyll and NOAA/NASA AVHRR Oceans Pathfinder SST imagery. Mean seasonal cycles were modeled as the sum of annual and semiannual harmonics. Interannual variability was estimated …


Cmg Training In Spatio-Temporal Statistical Analysis Of Multi-Platform Ocean Optical Observations, Mary Jane Perry Oct 2004

Cmg Training In Spatio-Temporal Statistical Analysis Of Multi-Platform Ocean Optical Observations, Mary Jane Perry

University of Maine Office of Research Administration: Grant Reports

This project will be a five-week summer school on the topic of spatio-temporal statistical analysis and its application to multi-platform, multi-sensor bio-optical oceanic data. The summer school seeks to address some of the analysis challenges anticipated as the Integrated Ocean Observing System is established. These are associated with the very diverse range of spatial and temporal sampling afforded by the different components of such a system and contemporaneous process experiments. Statistical experts in spatial information engineering with experience in collaboration with ocean scientists will discuss some of the modern tools for statistical analysis of such data and associated challenges, while …


Coastal Change And Beach Ridges Along The Northwest Coast Of Peru: Image And Gis Analysisof The Chira, Piura, And Colán Beach-Ridge Plains, Stacy Shafer Rogers, Daniel H. Sandweiss, Kirk A. Maasch, Daniel F. Belknap, Peggy Agouris Oct 2004

Coastal Change And Beach Ridges Along The Northwest Coast Of Peru: Image And Gis Analysisof The Chira, Piura, And Colán Beach-Ridge Plains, Stacy Shafer Rogers, Daniel H. Sandweiss, Kirk A. Maasch, Daniel F. Belknap, Peggy Agouris

Anthropology Faculty Scholarship

Since approximately 5200 cal yrs BP, five sets of eight to nine beach ridges were built and preserved along the northwestern Peruvian coastal desert (3o30'S-9oS). Potential ridge-building mechanisms in the hyper-arid environment of northwest Peru include El Nifio floods and storms, seismic activity, and sea-level change, as well as more gradualc limate changes that affectedc oastal morphologyI. mage processinga nd GeographicI nformationS ystem (GIS) methods were used to analyze aerial photographs and measure historic coastal patterns along three beach-ridge plains over a 37-year time period. Coastal features were digitized from image mosaics of each ridge plain at different time intervals …


Deglacial Chronology Of The Northern Scott Coast From Relative Sea-Level Curves, Brenda Hall Aug 2004

Deglacial Chronology Of The Northern Scott Coast From Relative Sea-Level Curves, Brenda Hall

University of Maine Office of Research Administration: Grant Reports

This award provides support for three years for a project to develop a radiocarbon chronology for recession of grounded ice from the northwestern Ross Sea Embayment (northern Scott Coast) since the Last Glacial Maximum (LGM). A key unresolved question in Antarctic glaciology concerns the stability of the marine-based West Antarctic ice sheet (WAIS). One way to gain insight into present and future stability is to examine its past behavior. In particular, the timing of deglaciation from the LGM position on the continental shelf is critical for isolating the mechanisms (sea level, climate, ocean temperature, and internal dynamics) that control WAIS …


Biology And Ecology Of Larval Lobsters (Homarus Americanus): Implications For Population Connectivity And Larval Transport, Eric R. Annis Aug 2004

Biology And Ecology Of Larval Lobsters (Homarus Americanus): Implications For Population Connectivity And Larval Transport, Eric R. Annis

Electronic Theses and Dissertations

The connectivity of marine populations and the degree to which they are considered open or closed has important implications for the ecology, management, and resilience of commercially harvested species. Larval exchange is a primary determinant of the level of connectivity between populations, and this thesis examines the intrinsic and extrinsic factors influencing larval transport and the distribution of larvae of the American lobster (Homarus americanus). The potential for larval transport is directly proportional to the planktonic larval duration. Our field data suggest development times in situ were up to three times faster than previous laboratory development times, indicating that potential …


Acquisition Of Digitial Geophysical Equipment For University Of Maine Sea-Level, Coastal And Lacustrine Research, Daniel Belknap, Joseph Kelley Apr 2004

Acquisition Of Digitial Geophysical Equipment For University Of Maine Sea-Level, Coastal And Lacustrine Research, Daniel Belknap, Joseph Kelley

University of Maine Office of Research Administration: Grant Reports

This Major Research Instrumentation award to University of Maine provides geophysical instrumentation for study of sea level and related coastal research. Consisting of a side-scan sonar system, seismic reflection profiler, digital data processing system and a vibracorer, it will be particularly used for research into evolution of coastal and nearshore systems and climate change in glaciomarine environments, especially the Gulf of Maine and adjacent environs. Research plans by University of Maine faculty and students will focus on the acquisition of data needed to model processes of change near former ice sheet margins. The facility plans to build on research partnerships …


Expansion And Renovation Of The Darling Marine Center Library, Kevin Eckelbarger Mar 2004

Expansion And Renovation Of The Darling Marine Center Library, Kevin Eckelbarger

University of Maine Office of Research Administration: Grant Reports

This award provides partial funding for expansion and modernization of the library at The Darling Marine Center. The library currently contains more marine-related holdings than any other library in Maine, and is an important resource for researchers and students interested in the biology of the Gulf of Maine and the Maine coast. Because of current space limitations, a third of the library's holdings are stored in other buildings and attic spaces. The library is not wheelchair accessible, has no significant study space, and provides only limited access to electronic databases. The proposed changes include: 1) construction of a 1,500 sq. …


Collaborative Research: Southern Andes Paleoclimate; A Testof Abrupt Ocean-Atmosphere Reorganizations In Glacial Cycle, George Denton Feb 2004

Collaborative Research: Southern Andes Paleoclimate; A Testof Abrupt Ocean-Atmosphere Reorganizations In Glacial Cycle, George Denton

University of Maine Office of Research Administration: Grant Reports

In the late 1980s, Broecker and Denton prepared papers on the concept that glacial-to-interglacial transitions involved global reorganizations of the ocean-atmosphere system (Broecker, W. S. and Denton, G. H., 1989. The role of ocean-atmosphere reorganizations in glacial cycles. Geochimica et Cosmochimica Acta, 53, 2465-2501; Broecker, W. S. and Denton, G. H., 1990, What drives glacial cycles? Sci. American, 262, 49-56). These reorganizations were thought to constitute jumps of Earth's climate systems between stable modes of operation, and they featured changes in the greenhouse-gas content or reflectivity of the atmosphere. In that concept, switches in thermohaline circulation, resulting from changes in …


Millenial-Scale Climatic Oscillations In New Zealand During The Last Glacial Cycle; Pep Iii Transect, George H. Denton Feb 2004

Millenial-Scale Climatic Oscillations In New Zealand During The Last Glacial Cycle; Pep Iii Transect, George H. Denton

University of Maine Office of Research Administration: Grant Reports

Millennial-Scale Climatic Oscillations in New Zealand During the Last Glacial Cycle: PEP III Transect Paleoclimate records from Greenland ice cores and North Atlantic sediments indicate that the glacial climate over the North Atlantic basin was punctuated with large and frequent abrupt climatic changes (Dansgaard-Oeschger and Henrich events). Because the events first appeared to have been regionally restricted, most explanations have invoked regional forcing mechanisms. But quite a different perspective would emerge if these events were shown to be of this global-scale. SGER award supports a reconnaissance study of the glacial and vegetative paleoclimate record of the massive morainal deposits of …


El Niño Suppresses Antarctic Warming, Nancy A. N. Bertler, Peter J. Barrett, Paul Andrew Mayewski, Ryan L. Fogt, Karl J. Kreutz, James Shulmeister Jan 2004

El Niño Suppresses Antarctic Warming, Nancy A. N. Bertler, Peter J. Barrett, Paul Andrew Mayewski, Ryan L. Fogt, Karl J. Kreutz, James Shulmeister

Earth Science Faculty Scholarship

Here we present new isotope records derived from snow samples from the McMurdo Dry Valleys, Antarctica and re-analysis data of the European Centre for Medium-Range Weather Forecasts (ERA-40) to explain the connection between the warming of the Pacific sector of the Southern Ocean [Jacka and Budd, 1998; Jacobs et al., 2002] and the current cooling of the terrestrial Ross Sea region [Doran et al., 2002a]. Our analysis confirms previous findings that the warming is linked to the El Niño Southern Oscillation (ENSO) [Kwok and Comiso, 2002a, 2002b; Carleton, 2003; Ribera and Mann …


Variability In Accumulation Rates From Gpr Profiling On The West Antarctic Plateau, Vandy B. Spikes, Gordon S. Hamilton, Steven A. Arcone, Susan Kaspari, Paul Andrew Mayewski Jan 2004

Variability In Accumulation Rates From Gpr Profiling On The West Antarctic Plateau, Vandy B. Spikes, Gordon S. Hamilton, Steven A. Arcone, Susan Kaspari, Paul Andrew Mayewski

Earth Science Faculty Scholarship

Isochronal layers in firn detected with ground-penetrating radar (GPR) and dated using results from ice-core analyses are used to calculate accumulation rates along a 100 km across-flow profile in West Antarctica. Accumulation rates are shown to be highly variable over short distances. Elevation measurements from global positioning system surveys show that accumulation rates derived from shallow horizons correlate well with surface undulations, which implies that wind redistribution of snow is the leading cause of this variability. Temporal changes in accumulation rate over 25-185 year intervals are smoothed to along-track length scales comparable to surface undulations in order to identify trends …


The Weather Of 1785: An Interdisciplinary Approach To Meteorological Reconstruction Using Forensic Synoptic Analysis, Louis K. Mcnally Jan 2004

The Weather Of 1785: An Interdisciplinary Approach To Meteorological Reconstruction Using Forensic Synoptic Analysis, Louis K. Mcnally

Electronic Theses and Dissertations

The purpose of the work is to discern differences and similarities in synoptic-scale rneteorology by reconstructing the weather of the year 1785 on a daily basis. This is accomplished by compiling data from both homogenous and non-homogenous observational records, and from historical anecdotal evidence as recorded in diaries, archives and contemporary publications. Through this reconstruction, it is possible to infer some characteristics of the global circulation of 1785. With forensic techniques, I develop meteorological parameters from anecdotal evidence. These data are combined with meteorological observational records to produce a database from which semi-diurnal weather maps can be constructed. Sources include …


Is Mwp 1a Real And Could It Have Originated In The Northern Hemisphere In Response To Bolling Warming, Sean D. Birkel Jan 2004

Is Mwp 1a Real And Could It Have Originated In The Northern Hemisphere In Response To Bolling Warming, Sean D. Birkel

Electronic Theses and Dissertations

Meltwater Pulse 1A (MWP 1A) is thought to have encompassed an abrupt rise in sea-level of 19 - 24 m ca. 14,000 calendar years B.P. The postulated rate of sea-level rise during the event was 24 - 50 mrnJyr. In contrast, the average rate of change during the overall glacial termination was 13 mrn/yr. Although MWP 1A is commonly accepted at face value, a compilation of all basic data points casts doubts on its validity. The Laurentide Ice Sheet (LIS) is commonly cited as the source of MWP 1A. Accelerated discharge of freshwater from the ice sheet could have weakened …


A 200-Year Sulfate Record From 16 Antarctic Ice Cores And Associations With Southern Ocean Sea Ice Extent, Daniel A. Dixon Jan 2004

A 200-Year Sulfate Record From 16 Antarctic Ice Cores And Associations With Southern Ocean Sea Ice Extent, Daniel A. Dixon

Electronic Theses and Dissertations

Data from sixteen, 50m- to 115m-deep, sub-annually dated ice cores are used to examine the recent spatial and temporal concentration variability of sea salt (ss)S04 " and excess (xs)S04 " over West Antarctica for the last 200 years. The preservation of seasonal layers throughout the length of each record results in a dating accuracy of better than one year based on known global scale volcanic events. A dual transport source for West 9 9 Antarctic SSSO4 " and XSSO4 " is observed: lower tropospheric for areas below 1000m elevation and mid-upper tropospheric/stratospheric for areas located above 1000m. The XSSO4 " …