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Understanding the causes of relative sea level rise requires knowledge of changes to both land (uplift and subsidence) and sea level. However, measurements of coastal uplift or subsidence are almost completely lacking in western Alaska. This project provided precise measurements of prioritized benchmarks across the Western Alaska geography, improving the network of published tidal benchmark elevations, allowing for tidal datum conversion in more places, and providing a necessary component for improved inundation studies in coastal communities and low-lying areas. The project’s map of vertical velocities (uplift/subsidence) of western Alaska (see ‘Final Project Report’ & ‘Vertical Velocity Map’, below) will be combined...
Categories: Data;
Tags: Academics & scientific researchers,
COASTAL AREAS,
COASTAL AREAS,
COASTAL ELEVATION,
COASTAL ELEVATION,
Time series data of water surface elevation and wave height were acquired at ten locations for 518 days (in three separate deployments) off the south coast of Kwajalein Island, Marshall Islands, in support of a study on the coastal circulation patterns and the transformation of surface waves over the coral reefs. The relative placement of sensors on the reefs were as follows: KWA13W1 and KWA13E1 – fore reef KWA13W2 and KWA13E2 – outer reef flat KWA13W1 and KWA13E1 – middle reef flat KWA13W1 and KWA13E1 – inner reef flat
The purpose of this study is to evaluate potential tsunami hazards for the community of Whittier and western Passage Canal area. We numerically model the extent of inundation due to tsunami waves generated from earthquake and landslide sources. Tsunami scenarios include a repeat of the tsunami triggered by the 1964 Great Alaska Earthquake, as well as tsunami waves generated by a hypothetically extended 1964 rupture, a hypothetical Cascadia megathrust earthquake, hypothetical earthquakes in Prince William Sound, and Kodiak asperities of the 1964 rupture. Local underwater landslide and rockslide events in Passage Canal are also considered as credible tsunamigenic scenarios. Results of numerical modeling combined with...
The purpose of this study is to evaluate potential tsunami hazards for the community of Sitka. We numerically modeled the extent of inundation from tsunami waves generated by near- and far-field tectonic sources. We performed numerical modeling of historic events at Sitka, such as the tsunami triggered by the 1964 Great Alaska Earthquake, and the tsunami waves generated by the recent 2011 Tohoku and 2012 Haida Gwaii earthquakes. Hypothetical tsunami scenarios include variations of the extended 1964 rupture, megathrust earthquakes in the Alaska Peninsula region and in the Cascadia subduction zone, and a thrust earthquake in the region of the Queen Charlotte-Fairweather fault zone. Results of numerical modeling combined...
Global climate change is altering the natural state of the earth. Ecosystems around the world are being affected with a large concern being the availability of freshwater. As a result of climate change Hawaiʻi is predicted to experience a significant decrease in precipitation. And although Hawaiʻi is not currently experiencing unavailability of freshwater resources the focus of this study is to begin to understand one of the most abundant freshwater resources in Hawaiʻi, freshwater springs. Three approaches were used to begin understanding the freshwater springs in Keaukaha, HI; reading through literature, conducting field surveys as well as conducting informal interviews. Through the field surveys it was found...
These data show monthly mean sea level for the San Francisco Bay from July 1854 through December 2021. This dataset is a compilation of two locations since one location had a shorter record: the Alameda (Naval Air Station) station was used from April 1939 through December 2021 while the San Francisco station was used from July 1854 through March 1939 [Holgate and others (2013); PAMSL (2018)]. The Alameda gauge was used when these data were available due to its location being further east in San Francisco Bay and therefore a better fit for the updated Central Valley Hydrologic Model (CVHM2). The San Francisco station is located just east of the Golden Gate Bridge at 37.806667°, -122.465° while the Alameda station...
Categories: Data;
Tags: Alameda,
Alameda Naval Air Station (Closed),
California,
Central Valley,
Golden Gate,
Time series data of wave height and water surface elevation were acquired for 100 days at three locations off of the island of Nanumanga, three locations off of the island of Nanumea, three locations off of the island of Nui, two locations off of the island of Nikulaelae, and two locations off of the island of Niulakita, in the island nation of Tuvalu, in support of a study on the coastal circulation patterns and the transformation of surface waves over the coral reefs. The relative placement of sensors on the reefs were as follows: TVL19NG3, TVL19NM1, TVL19NU1, TVL19NK1 and TVL19NL1 – offshore TVL19NG1, TVL19NM2 and TVL19NU2 – reef crest TVL19NG3, TVL19NM3, TVL19NU3, TVL19NK2 and TVL19NL2 – reef...
Time series data of wave height and water surface elevation were acquired for 147 days at four locations off of the north coast and four locations off the south coast of Buck Island, U.S. Virgin Islands, in support of a study on the coastal circulation patterns and the transformation of surface waves over the coral reefs. The relative placement of sensors on the reefs were as follows: BUI15S1T and BUI15N1T – fore reef BUI15S2T and BUI15N2T – outer reef flat BUI15S3T and BUI15N3T – middle reef flat BUI15S4T and BUI15N4T – inner reef flat
Staff from Alaska Earthquake Center, Geophysical Institute and Alaska Division of Geological & Geophysical Surveys evaluated potential potential tsunami hazard for the communities of Kodiak, Womens Bay, and for the U.S. Coast Guard base on Kodiak Island by numerically modeling the extent of inundation from tsunami waves generated by hypothetical earthquake sources. Worst-case hypothetical scenarios are defined by analyzing results of a sensitivity study of the tsunami dynamics related to various slip distributions along the Alaska-Aleutian megathrust. The worst-case scenarios for the Kodiak communities are thought to be the subduction zone earthquakes offshore Kodiak Island with their greatest slip at 5-35 km (3.1-22...
Time series data of wave height and water surface elevation were acquired at ten locations for 75 days south of Lahaina, off of the west coast of the island of Maui, Hawaii, in support of a study on the coastal circulation patterns and the transformation of surface waves over the coral reefs. The relative placement of sensors on the reefs were as follows: MAU17TP1 and MAU17LA1 – middle fore reef MAU17TP2 and MAU17LA2 – upper fore reef MAU17TP3 and MAU17LA3 – outer reef flat MAU17TP4 and MAU17LA4 – middle reef flat MAU17TP5 and MAU17LA5 – inner reef flat
Time series data of wave height and water surface elevation were acquired for 147 days at eleven locations, in two cross-reef transects, off of the west coast of Rincon, Puerto Rico, in support of a study on the coastal circulation patterns and the transformation of surface waves over the coral reefs. The relative placement of sensors on the reef were as follows: PRI19N01 – offshore reef crest, north transect PRI19N02, PRI19N03 – offshore reef flat, north transect PRI19S03 – offshore reef flat, south transect PRI19N04, PRI19N05 and PRI19N06 – inner reef flat, north transect PRI19S04, PRI19S05, PRI19S06, PRI19S07 and PRI19S08 – inner reef flat, south transect
On November 8, 2011, an extra-tropical cyclone with a low pressure of 945 millibars developed over the Bering Sea and moved northeast across the western coast of Alaska. This large storm brought high winds (gusts of up to 85 mph) to the entire region and a storm surge of approximately 3 meters to parts of Norton Sound. The storm caused extensive flooding in the lower portion of Golovin on the afternoon of November 9, 2011. A team of Alaska Division of Geological & Geophysical Surveys (DGGS) scientists visited Golovin on November 15, 2011, to document peak water levels, runup elevations, and inundation extents caused by this event. These data were combined with photographs taken by local residents during the event...
The western coastline of Alaska is highly susceptible to coastal storms, which can cause coastal erosion, flooding, and have other pernicious effects to the environment and commercial efforts. The reduction in ice coverage due to climate change could potentially increase the frequency and degree of coastal flooding and erosion. Further, estuaries and delta systems act as conduits for storm surges, so when there is less nearshore ice coverage, these systems could introduce storm surge into terrestrial environments unaccustomed to saline intrusion, flooding, or other alien biogeochemical factors.This project quantified the effect of reduced nearshore ice coverage on coastal flooding. The project developed a large...
Categories: Data;
Tags: Academics & scientific researchers,
COASTAL AREAS,
COASTAL AREAS,
COASTAL PROCESSES,
COASTAL PROCESSES,
The western coastline of Alaska is highly susceptible to coastal storms, which can cause coastal erosion, flooding, and have other pernicious effects to the environment and commercial efforts. The reduction in ice coverage due to climate change could potentially increase the frequency and degree of coastal flooding and erosion. Further, estuaries and delta systems act as conduits for storm surges, so when there is less nearshore ice coverage, these systems could introduce storm surge into terrestrial environments unaccustomed to saline intrusion, flooding, or other alien biogeochemical factors.This project quantified the effect of reduced nearshore ice coverage on coastal flooding. The project developed a large...
Categories: Data;
Tags: Academics & scientific researchers,
COASTAL AREAS,
COASTAL AREAS,
COASTAL PROCESSES,
COASTAL PROCESSES,
Static occupations of tidal and geodetic benchmarks in Western Alaska were undertaken in the summers of 2013 and 2014. Project accomplishments far exceeded the proposed project objective of obtaining and sharing data for benchmarks in 8 different communities; in total, this work has resulted in the occupation of 44 benchmarks in 15 different communities. 32 of these datasets met National Geodetic Survey (NGS) minimum criteria for ‘shared solutions’ and have been uploaded to the Online Positioning User Service (OPUS) shared public database. This data has also been used to augment the tidal datum conversion database at the Alaska Division of Geological & Geophysical Surveys (DGGS) and the scientific geodetic database...
Categories: Data;
Tags: Academics & scientific researchers,
COASTAL AREAS,
COASTAL AREAS,
COASTAL ELEVATION,
COASTAL ELEVATION,
The purpose of this study is to evaluate potential tsunami hazards for the Prince William Sound communities of Cordova and Tatitlek. We numerically model the extent of inundation from tsunami waves generated by earthquake sources and consider the results in light of historical observations. Tsunami scenarios include a repeat of the tsunami triggered by the 1964 Great Alaska Earthquake as well as tsunami waves generated by the following hypothetical scenarios: An extended 1964 rupture, a Cascadia megathrust earthquake, various earthquakes in Prince William Sound, and a Tohoku-type earthquake in the Gulf of Alaska region. Results of our numerical modeling, combined with historical observations, are designed to provide...
The western coastline of Alaska is highly susceptible to coastal storms, which can cause coastal erosion, flooding, and have other pernicious effects to the environment and commercial efforts. The reduction in ice coverage due to climate change could potentially increase the frequency and degree of coastal flooding and erosion. Further, estuaries and delta systems act as conduits for storm surges, so when there is less nearshore ice coverage, these systems could introduce storm surge into terrestrial environments unaccustomed to saline intrusion, flooding, or other alien biogeochemical factors.This project quantified the effect of reduced nearshore ice coverage on coastal flooding. The project developed a large...
Categories: Data;
Tags: Academics & scientific researchers,
COASTAL AREAS,
COASTAL AREAS,
COASTAL PROCESSES,
COASTAL PROCESSES,
Understanding the causes of relative sea level rise requires knowledge of changes to both land (uplift and subsidence) and sea level. However, measurements of coastal uplift or subsidence are almost completely lacking in western Alaska. This project provided precise measurements of prioritized benchmarks across the Western Alaska geography, improving the network of published tidal benchmark elevations, allowing for tidal datum conversion in more places, and providing a necessary component for improved inundation studies in coastal communities and low-lying areas. The project’s map of vertical velocities (uplift/subsidence) of western Alaska (see ‘Final Project Report’ & ‘Vertical Velocity Map’, below) will be combined...
Categories: Data;
Tags: Academics & scientific researchers,
COASTAL AREAS,
COASTAL AREAS,
COASTAL ELEVATION,
COASTAL ELEVATION,
Time series data of wave height and water surface elevation were acquired for 135 days at six locations off of the west coast of Rincon, Puerto Rico, in support of a study on the coastal circulation patterns and the transformation of surface waves over the coral reefs. The relative placement of sensors on the reef were as follows: PRI20N01 – offshore PRI20N02 and PRI20N03 – fore reef PRI20N35, PRI20N04 and PRI20N45 – reef flat
The Bushy Park Reservoir is a relatively shallow impoundment in a semi-tropical climate and is the principal water supply for the 400,000 people of the City of Charleston and the surrounding areas including the industries in the Bushy Park Industrial Complex. Although there is an adequate supply of freshwater in the reservoir, there are taste-and-odor water-quality concerns. The U.S. Geological Survey (USGS), in cooperation with the Charleston Water System, monitored the hydrology and water-quality conditions in the Bushy Park Reservoir immediately before, during, and after a unique shutdown period when the average daily 800-cubic-feet-per-second withdrawals by South Carolina Electric and Gas (SCE+G) Williams Station...
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