Physical Sciences and Mathematics Commons^™

Soil Organic Matter Diagenetic State Informs Boreal Forest Ecosystem Feedbacks To Climate Change, Allison N. Myers-Pigg, Karl Kaiser, Ronald Benner, Susan E. Ziegler

Faculty Publications

The fate of soil organic carbon (SOC) in boreal forests is dependent on the integrative ecosystem response to climate change. For example, boreal forest productivity is often nitrogen (N) limited, and climate warming can enhance N cycling and primary productivity. However, the net effect of this feedback on the SOC reservoir and its longevity with climate change remain unclear due to difficulty in detecting small differences between large and variable carbon (C) fluxes needed to determine net changes in soil reservoirs. The diagenetic state of SOC – resulting from the physicochemical and biological transformations that alter the original biomolecular composition …

The Response Of Sea Ice And High-Salinity Shelf Water In The Ross Ice Shelf Polynya To Cyclonic Atmosphere Circulations, Xiaoqiao Wang, Zhaoru Zhang, Michael S. Dinniman, Petteri Uotila, Xichen Li, Meng Zhou

CCPO Publications

Coastal polynyas in the Ross Sea are important source regions of high-salinity shelf water (HSSW) – the precursor of Antarctic Bottom Water that supplies the lower limb of the thermohaline circulation. Here, the response of sea ice production and HSSW formation to synoptic-scale and mesoscale cyclones was investigated for the Ross Ice Shelf Polynya (RISP) using a coupled ocean–sea ice–ice shelf model targeted on the Ross Sea. When synoptic-scale cyclones prevailed over RISP, sea ice production (SIP) increased rapidly by 20 %–30 % over the entire RISP. During the passage of mesoscale cyclones, SIP increased by about 2 times over …

Supporting Dataset For Observed And Projected Global Warming Pressure On Coastal Hypoxia, Michael M. Whitney

Department of Marine Sciences

This archive contains the supporting dataset for the Biogeosciences article “Observed and projected global warming pressure on coastal hypoxia” by Michael M. Whitney. The main objective of the article is studying global patterns exacerbating coastal hypoxia by analyzing linear trends in SST, surface oxygen capacity (saturation concentration), and (vertical-minimum) oxygen concentration. Observations from a satellite-derived SST global climate dataset are analyzed to provide a context of coastal SST and oxygen-capacity trends observed over the last four decades. New analysis of 21st century projections from the Community Earth System Model (CESM) Large Ensemble Project is completed for coastal areas. Observed and …

Simulated Response Of St. Joseph Bay, Florida, Seagrass Meadows And Their Belowground Carbon To Anthropogenic And Climate Impacts, Marie Cindy Lebrasse, Blake A. Schaeffer, Richard C. Zimmerman, Victoria J. Hill, Megan M. Coffer, Peter J. Whitman, Wilson B. Salls, David D. Graybill, Christopher L. Osburn

OES Faculty Publications

Seagrass meadows are degraded globally and continue to decline in areal extent due to human pressures and climate change. This study used the bio-optical model GrassLight to explore the impact of climate change and anthropogenic stressors on seagrass extent, leaf area index (LAI) and belowground organic carbon (BGC) in St. Joseph Bay, Florida, using water quality data and remotely-sensed sea surface temperature (SST) from 2002 to 2020. Model predictions were compared with satellite-derived measurements of seagrass extent and shoot density from the Landsat images for the same period. The GrassLight-derived area of potential seagrass habitat ranged from 36.2 km2 …

Comparison Of Modern And Mid-Holocene Benthic Foraminifera To Assess Recent Environmental Change In Almirante Bay, Caribbean Panama, Maria N. Gudnitz

FIU Electronic Theses and Dissertations

This study used the diversity and distribution of benthic foraminiferal assemblages of Almirante Bay, Caribbean Panama, as environmental proxies to compare modern coral, seagrass and mangrove habitats to mid-Holocene coral reef facies on the island of Isla Colón, to investigate both natural and human-influenced changes.

The modern study associated species and assemblage characteristics with environmental conditions related to degraded water quality. Assemblages were fairly similar among neighboring habitats but differed in species proportions, while several stress-tolerant taxa might indicate eutrophic conditions. Diversity appeared to be regionally controlled by freshwater input irrespective of habitat type, was generally lower near the mainland …

Anthropogenic Change On The Distribution Of Marine Megafauna And Their Prey, Baylie Fadool

Honors Theses

Anthropogenic change is impacting the distribution and survival of marine megafauna and their prey. Humans are changing every aspect of the marine environment, with effects reaching as large as changing the composition of marine environments to directly overexploiting species through the fishing industry. The role that marine megafauna play in balancing ecosystems, including as top apex predators, leads to detrimental results in the absences and population declines of these species. Migrations and declines due to threats on marine apex predator species will alter their environments by causing mesopredator release and changes in community structure, which is often associated with reduced …

A Pre-Industrial Sea-Level Rise Hotspot Along The Atlantic Coast Of North America, W. R. Gehrels, Sönke Dangendorf, N. L. M. Barlow, M. H. Saher, A. J. Long, P. L. Woodworth, C. G. Piecuch, K. Berk

CCPO Publications

The Atlantic coast of North America north of Cape Hatteras has been proposed as a “hotspot” of late 20th century sea‐level rise. Here we test, using salt‐marsh proxy sea‐level records, if this coast experienced enhanced sea‐level rise over earlier multidecadal‐centennial periods. While we find in agreement with previous studies that 20th century rates of sea‐level change were higher compared to rates during preceding centuries, rates of 18th century sea‐level rise were only slightly lower, suggesting that the “hotspot” is a reoccurring feature for at least three centuries. Proxy sea‐level records from North America (Iceland) are negatively (positively) correlated with centennial …

Improving Thorium-230 Determination In Marine Sediment, Katherine Mateos

Independent Study Project (ISP) Collection

Our oceans are intimately related to the climate of our planet. Paleoceanographic approaches aim to study oceans through geologic time to improve models of future climate. Radioisotopes provide us with chemical tracers that help us understand change through time. The uraniumseries decay chain contains thorium-230, a decay product of uranium-234. This isotope is useful to paleoceanographers in its disequilibrium to its parent isotope and in determining the flux of sediment falling to the ocean floor. In order to use 230Th to study oceans, we must be able to accurately measure the amount of thorium in sediment samples. Thorium is found …

Impacts Of Basin-Scale Climate Modes On Coastal Sea Level: A Review, Weiqing Han, Detlef Stammer, Philip Thompson, Tal Ezer, Hindu Palanisamy, Xuebin Zhang, Catia M. Domingues, Lei Zhang, Dongliang Yuan

CCPO Publications

Global sea level rise (SLR) associated with a warming climate exerts significant stress on coastal societies and low-lying island regions. The rates of coastal SLR observed in the past few decades, however, have large spatial and temporal differences from the global mean, which to a large part have been attributed to basin-scale climate modes. In this paper, we review our current state of knowledge about climate modes’ impacts on coastal sea level variability from interannual-to-multidecadal timescales. Relevant climate modes, their impacts and associated driving mechanisms through both remote and local processes are elaborated separately for the Pacific, Indian and Atlantic …

Perspectives On Chemical Oceanography In The 21st Century: Participants Of The Come Aboard Meeting Examine Aspects Of The Field In The Context Of 40 Years Of Disco, Andrea J. Fassbender, Hilary I. Palevsky, Todd R. Martz, Anitra E. Ingalls, Martha Gledhill, Sarah E. Fawcett, Jay A. Brandes, Lihini I. Aluwihare, The Participants Of Come Aboard, Disco Xxv

OES Faculty Publications

The questions that chemical oceanographers prioritize over the coming decades, and the methods we use to address these questions, will define our field's contribution to 21st century science. In recognition of this, the U.S. National Science Foundation and National Oceanic and Atmospheric Administration galvanized a community effort (the Chemical Oceanography MEeting: A BOttom-up Approach to Research Directions, or COME ABOARD) to synthesize bottom-up perspectives on selected areas of research in Chemical Oceanography. Representing only a small subset of the community, COME ABOARD participants did not attempt to identify targeted research directions for the field. Instead, we focused on how best …

Models Describing The Sea Level Rise In Key West, Florida, Karm-Ervin Jean

FIU Electronic Theses and Dissertations

Lately, we have been noticing an unusual rise in the sea level near many Floridian cities. By 2060, scientists believe that the sea level in the city of Key West will reach between 22.86 to 60.96 centimeters (Strauss et al. 2012). The consequences of sea level rise are unpleasant by gradually tearing away our beaches and natural resources, destroying our homes and businesses, etc. Definitively, a continual increase of the sea level will affect everyone either directly or indirectly.

In this study, the sea level measurements of four Floridian coastal cities (including Key West) are collected in order to describe …

Kenyan Climate Variation Assessment Through Rainfall Anomalies And Sea Surface Temperature (Sst) Correlations, Kimberly E. Lykens

STAR Program Research Presentations

The diverse and varied climate of Eastern Africa’s Kenya is home to an agriculturally dependent populace, in which farmers and other related economic sectors make up the majority of livelihoods and gross domestic product. Recurring droughts and severe flooding are major concerns for local farmers and governmental entities. The purpose of this study is to identify and categorize differences in rainfall trends over Kenya and to examine relationships between seasonal rainfall anomalies of sea surface temperature (SST), with an ultimate goal to improve predictions of wet season rainfall amounts. The analysis began with data from 27 national and cooperative weather …

Ip25: A Molecular Proxy Of Sea-Ice Duration In The Bering And Chukchi Seas, Cecily J. Sharko

Masters Theses 1911 - February 2014

Seasonal sea ice is an important component of the global climate system. Sea ice influences exchange rates of heat, moisture, and gas between the ocean and atmosphere. Sea ice also plays critical roles in high latitude ecosystems and marine carbon cycling. Records of sea-ice extent and duration in the Arctic Ocean and its marginal seas through geologic time are valuable resources for better understanding the intricate relationships between sea ice and climate.

IP25, a compound biosynthesized exclusively by diatoms associated with sea ice, has been used to construct qualitative records of sea ice from sediment cores in some areas of …

Measurements Of Salinity In The Coastal Ocean: A Review Of Requirements And Technologies, Catherine Woody, Eddie Shih, Jerry Miller, Thomas Royer, Larry P. Atkinson, Richard S. Moody

CCPO Publications

Salinity, a measure of the dissolved salts in seawater, is a fundamental property of seawater and basic to understanding biological and physical processes in coastal waters. In the open ocean long term salinity measurements are identified as necessary to understand global climate studies, hydrological cycle, and circulation. In the coastal oceans, information on salinity is critical to understanding biological effects on ecosystem function such as disease, nursery grounds, or harmful algal blooms and on physical processes such as freshwater runoff estuarine mixing, and coastal currents. While the importance of salinity is recognized, little attention has been given to making routine …

Effect Of Wind Changes During The Last Glacial Maximum On The Circulation In The Southern Ocean, John M. Klinck, David A. Smith

CCPO Publications

Present-day surface wind stress climatology is manipulated to simulate wind conditions during the last glacial maximum. These estimated wind fields force a one-layer, wind-driven numerical model of the southern ocean to determine if a change in the strength of the surface wind stress can shift the location of the Antarctic Polar Front, which is part of the Antarctic Circumpolar Current. A change in the forcing by a factor of 0.5-2.0 results in a change in the speed of the flow by an identical factor with no change in position. However, if the present-day wind climatology is shifted meridionally there is …

Development And Evaluation Of Tracer Particles For Use In Microzooplankton Herbivory Studies, Mary Putt

OES Faculty Publications

Two methods of preparing algae for use as tracer particles in single species measurements of microzooplankton herbivory were evaluated. Algae were either heat-killed and labelled with 5-(4,6-dichlorotriazin-2-yl amino fluorescein) (DTAF) (Rublee & Gallegos 1989; Mar, Ecol. Prog. Ser. 51: 221-227) or stained with hydroethidine (HYD). Both DTAF and HYD-stained algae were readily visible within the digestive vacuoles of most microzooplankton collected in estuarine and coastal waters of Massachusetts (USA) and preserved with Lugol's iodine. However, DTAF was ineffective at staining several chromophytic algae and the heat-kill process reduced cell volume by ≥ 50% in several of the algae which were …

Vims-Blm Second Order Wave Climate Model And Wave Climatology Of Baltimore Canyon Trough Shelf Area, Victor Goldsmith

Reports

The Wave Climate Model of the Baltimore Canyon Trough Shelf area encompassing the designated lease blocks was extended, refined, and comparisons made with real wave data, as part of this year's contract (Figures 15-la and 15-lb). This modified model w.as produced to refine the 1975 model so that more definitive statements and interpretations could be concluded, based on more detailed data, in the evaluation of the baseline data. A set of computer-generated graphics utilizing a greater depth data point density (0.25 NM), to al.low site-specific evaluation of conditions within the lease block area, were produced.