Filters: Tags: Coral Reefs (X)
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Time series data of water surface elevation, wave height, water column currents and temperature, and suspended sediment were acquired for 6 weeks on a coral reef off Jurabi Point, Ningaloo Coast UNESCO World Heritage site in Western Australia in support of a study on the circulation and sediment transport patterns of these reefs.
This data release includes representative cluster profiles (RCPs) from a large (>24,000) selection of coral reef topobathymetric cross-shore profiles (Scott and others, 2020). We used statistics, machine learning, and numerical modelling to develop the set of RCPs, which can be used to accurately represent the shoreline hydrodynamics of a large variety of coral reef-lined coasts around the globe. In two stages, the data were reduced by clustering cross-shore profiles based on morphology and hydrodynamic response to typical wind and swell wave conditions. By representing a large variety of coral reef morphologies with a reduced number of RCPs, a computationally feasible number of numerical model simulations can be...
Categories: Data;
Types: NetCDF OPeNDAP Service;
Tags: CMHRP,
Coastal and Marine Hazards and Resources Program,
Commonwealth of the Northern Mariana Islands,
Marine Geology,
PCMSC,
This portion of the data release presents a bathymetric point cloud from an unoccupied aerial system (UAS) survey of the coral reef off Waiakane, Molokai, Hawaii, on 24 June 2018. The point cloud has been corrected for the effects of refraction using the techniques described in Dietrich (2017a). The point cloud was created from structure-from-motion (SfM) processing of aerial imagery collected using a UAS with a Ricoh GR II digital camera fitted with a circular polarizing filter. During the survey, a pressure sensor was deployed in the survey area to gain an accurate measurement of the water surface elevation (WSE). After a preliminary dense point cloud was derived from SfM processing, the WSE was used to calculate...
This portion of the data release presents a bathymetric digital surface model (DSM) from an unoccupied aerial system (UAS) survey of the coral reef off Waiakane, Molokai, Hawaii, on 24 June 2018. The DSM has a horizontal resolution of 10 centimeters per pixel and has been corrected for the effects of refraction using the techniques described in Dietrich (2017a). The DSM was created from structure-from-motion (SfM) processing of aerial imagery collected using a UAS with a Ricoh GR II digital camera fitted with a circular polarizing filter. During the survey, a pressure sensor was deployed in the survey area to derive an accurate measurement of the mean water surface elevation (WSE). After a preliminary dense point...
Passive membrane samplers—semipermeable membrane devices and polar organic chemical integrative samplers—were deployed for 22 continuous days at 7 sites along the West Maui, Hawai'i, coastline in February and March 2017 to assess organic contaminants at shallow coral reef ecosystems from diverse upstream inputs.
Categories: Data;
Tags: CMHRP,
Coastal and Marine Hazards and Resources Program,
Environmental Health,
Geochemistry,
Honokeana,
Ecosystems such as coral reefs and mangroves provide an effective first line of defense against coastal hazards and represent a promising nature-based solution to adapt to sea-level rise. In many areas, coral reefs cause waves to break and lose energy, allowing for sediment to accumulate on the inshore portion of reef flats (i.e. the shallowest, flattest part of a reef) and mangroves to establish. Mangroves cause further attenuation (i.e. energy loss) waves and storm surge as water moves through roots and trunks of the trees. Together, these ecosystems provide valuable protection from coastal flooding, but is unclear how this protection may be affected by sea-level rise. An assessment of future sea-level rise vulnerability...
Categories: Project;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: 2020,
CASC,
Coral Reefs,
Coral Reefs,
Data Visualization & Tools,
The conditions of coral reefs in the Hawaiian Islands are predicted to decline significantly from climate change over the next 100 years. To better prepare for the impacts of climate change on Hawaiian reefs, the research team uses a system of models to simulate ocean waves and circulation, rainfall and storm run-off, and coral reef community dynamics through the year 2100. These models will identify reef areas that are either vulnerable or resilient to the many stressors that the future may hold for reefs. The team’s hope is that this work can identify areas that might benefit from management actions to minimize local stressors such as land-based pollution. Through a collaborative partnership with state and federal...
Categories: Project;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: 2013,
CASC,
Completed,
Coral Reefs,
Coral Reefs,
Agriculture, though important to economic development and food security, is a source of increased sediment, nutrient, and pesticide runoff. Threats from sedimentation and pollution from inland sources were modeled for about 150 watersheds discharging along the Mesoamerican reef, and associated sediment plumes estimated.
Reef polygons have been classified by all local threats integrated (coastal development, marine-based pollution and damage, watershed-based pollution, and overfishing/destructive fishing. Values of 0 indicate low threat, 100 indicate medium threat, 1000 indicate high threat, and 1500 indicate very high threat.
This dataset shows summary statistics for relative erosion rate (REP), river flow, and sediment delivery estimated for each of over 150 watersheds draining along the Mesoamerican Reef.
Reef polygons have been classified by estimated threat from overfishing and destructive fishing. Threats to coral reefs from overfishing were evaluated based on coastal population density and extent of fishing areas (reef and shallow shelf areas), with adjustments to account for the increased demand due to proximity to large populations and market centers. Areas where destructive fishing occurs (with explosives or poisons) were also included, based on observations from monitoring and mapping provided by experts. Values of 0 indicate low threat, 100 indicate medium threat, 1000 indicate high threat.
Using basins derived from a hydrologically-corrected 30m resolution DEM as a unit for summary statistics, we provide a series of indicators focused on land-based sources fo threat within the US Virgin Islands. This includes indicators of a) the relative vulnerability of the land to erosion (based on slope, precipitation and soil erodibility); b) the relative erosion potential (REP) of the land, based on the relative vulnerability of the land, coupled with the current land cover type; c) the sediment delivery rate for each basin (percentage of eroded which reaches the river mouth); d) estimated sediment delivery for the basin, given current land use; e) the road density within the basin, and f) indicators of how...
ArcGIS layer package of relative classifications (low to high) for six resilience indicators and two anthropogenic stressors and a map of final relative resilience scores for 78 sites in the Commonwealth of the Northern Mariana Islands. The six resilience indicators are: bleaching resistance, coral diversity, coral recruitment, herbivore biomass, macroalgae cover and temperature variability. The two anthropogenic stressors are fishing access and nutrients and sediments. The resilience score map compares sites across all four of the surveyed islands: Saipan, Tinian, Aguijan, and Rota.
In 2007, a phase shift from corals to corallimorpharians (CM) was documented at Palmyra Atoll, Line Islands, centered around a shipwreck. Subsequent surveys revealed CM to be overgrowing the reef benthos, including corals and coralline algae, potentially placing coral ecosystems in the atoll at risk. This prompted the U.S. Fish and Wildlife Service, the lead management agency of the atoll, to remove the shipwreck. Subsequent surveys showed reversal of spread of CM around the ship impact site. We explain patterns of spread of the CM in terms of life history and local currents and show with a pilot study that pulverized bleach may be an effective tool to eradicate CM on a local scale. If applied strategically, particularly...
Coral reefs are some of the most biologically rich and economically valuable ecosystems in the world. They provide food, fishing, and recreation opportunities for millions of people, protect coastlines from storms, and shelter thousands of plant and animal species. However, climate change is contributing to the degradation of coral reefs in two significant ways: warming temperature and increasing acidification of ocean waters. Scientists are actively working to gather more specific information about how these factors will impact coral reef ecosystems. The purpose of this study was to identify differences in climate vulnerability among three important reef-building coral species in the Florida Keys. Researchers...
Categories: Project;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: 2011,
CASC,
Climate Change,
Completed,
Coral reefs,
This webinar was conducted on April 16, 2015. Reducing coral reef vulnerability to climate change requires that managers understand and support the natural resilience of coral reefs. To assist these managers, a team of researchers, supported by the Pacific Islands Climate Science Center (PI CSC) undertook a project to: 1) assess ecological resilience in the Commonwealth of the Northern Mariana Islands (CNMI), which is in the west Pacific near Guam, and 2) collaboratively develop a decision-support framework with local management partners for resilience-based management. The team used an approach that included surveys of 78 sites along reefs surrounding the most populated islands in CNMI (Saipan, Tinian/Aguijan,...
This data set consists of physics-based Delft3D-FLOW and SWAN hydrodynamic models input files used to study the wave-induced 3D flow over spur-and-groove (SAG) formations. SAG are a common and impressive characteristic of coral reefs. They are composed of a series of submerged shore-normal coral ridges (spurs) separated by shore-normal patches of sediment (grooves) on the fore reef of coral reef environments. Although their existence and geometrical properties are well documented, the literature concerning the hydrodynamics around them is sparse. Here, the three-dimensional flow patterns over SAG formations, and a sensitivity of those patterns to waves, currents, and SAG geometry were examined. Shore-normal shoaling...
Spatial surveys of water column physical properties were acquired with a conductivity-temperature-depth (CTD) profiler for four days in February 2015 and one day in July 2015 off the north coast of the island of Tutuila, American Samoa in support of a study on the coastal circulation patterns within and in the vicinity of the National Park of American Samoa.
Categories: Data;
Types: Citation,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: CMGP,
CONDUCTIVITY,
CORAL REEFS,
Coastal and Marine Geology Program,
DENSITY,
Dynamically downscaled future wave projections from SWAN model results for the main Hawaiian Islands
Projected wave climate trends from WAVEWATCH3 model output were used as input for nearshore wave models (for example, SWAN) for the main Hawaiian Islands to derive data and statistical measures (mean and top 5 percent values) of wave height, wave period, and wave direction for the recent past (1996-2005) and future projections (2026-2045 and 2085-2100). Three-hourly global climate model (GCM) wind speed and wind direction output from four different GCMs provided by the Coupled Model Inter-Comparison Project, phase 5 (CMIP5), were used as boundary conditions to the physics-based WAVEWATCH3 numerical wave model for the area encompassing the main Hawaiian islands. Two climate change scenarios for each of the four GCMs...
A set of physics-based XBeach Non-hydrostatic hydrodynamic model simulations (with input files here included) were used to evaluate how varying carbonate budgets, and thus coral reef accretion and degradation, affect alongshore variations in wave-driven water levels along the adjacent shoreline of Buck Island Reef National Monument (BUIS) for a number of sea-level rise scenarios, specifically during extreme wave conditions when the risk for coastal flooding and the resulting impact to coastal communities is greatest. These input files accompany the modeling conducted for the following publication: Toth, L.T., Storlazzi, C.D., Kuffner, I.B., Quataert, E., Reyns, J., McCall, R.T., Stathakopoulos, A., Hillis-Starr,...
Categories: Data;
Tags: Bathymetry and Elevation,
CMHRP,
Climatology,
Coastal and Marine Hazards and Resources Program,
Ecology,
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