Identification_Information: Citation: Citation_Information: Originator: Suleimani, E.N. Originator: Salisbury, J.B. Originator: Nicolsky, D.J. Originator: West, M.E. Publication_Date: 2019 Title: Tsunami inundation maps for Adak and Atka, Alaska Geospatial_Data_Presentation_Form: report and digital data Series_Information: Series_Name: Report of Investigation Issue_Identification: RI 2019-1 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 63 p., 6 sheets Online_Linkage: http://doi.org/10.14509/30186 Description: Abstract: We evaluate potential tsunami hazards for Adak and Atka by numerically modeling tsunami inundation generated by earthquakes along the Alaska-Aleutian subduction zone. Hypothetical worst-case scenarios are defined by analyzing tsunami dynamics related to various plausible earthquake slip distributions. Potential tsunami sources include megathrust earthquakes in the area of the Andreanof Islands, the Alaska Peninsula, and the Cascadia subduction zone. We consider scenarios similar to the 2011 Tohoku earthquake in Japan with maximum slip located on a shallow portion of the plate interface close to the seafloor trench. The maximum modeled tsunami wave height is 10-15 m (33-50 ft) in both Adak and Atka. The numerical simulations reveal that for some scenarios, the first wave could reach Adak and Atka as soon as 15 and 30 minutes after the earthquake, respectively. Significant wave activity could continue for more than 12 hours after the earthquake, and the predicted average time interval between successive waves is 45 minutes to 1 hour. Results presented here are intended to provide guidance to local emergency management agencies for tsunami inundation assessment, evacuation planning, and public education to mitigate future tsunami hazards. The complete report and digital data are available from the DGGS website: http://doi.org/10.14509/30186. Purpose: Results presented here are intended to provide guidance to local emergency management agencies in tsunami inundation assessment, evacuation planning, and public education to mitigate future tsunami hazards. Supplemental_Information: >max-flow-depth: Raster image depicting maximum composite flow depths over dry land. For each grid point, the pixel value provides the modeled depth of water (in meters) over previously dry land, representing the maximum depth value of all calculated tsunami scenarios. >max-inundation: Estimated, "maximum credible scenario" inundation line(s) that encompasses the maximum extent of flooding based on model simulation of all credible source scenarios and historical observations. The maximum credible scenario inundation lines are intended to be utilized as a basis for local tsunami hazard planning and development of evacuation maps. >mhhw-shoreline: MHHW (Mean Higher High Water) shoreline of the map area. The shoreline position is calculated from the boundary between positive (land) and negative (water) values in the supporting DEM. >post-earthquake-shoreline: The post-earthquake shoreline that corresponds to MHHW after modeled coseismic ground changes due to earthquakes. >scenarios-adak: Collection of shapefiles that depict the modeled potential maximum inundation by tsunami waves for each modeled scenario. Detailed information about each scenario can be found in the accompanying report. >scenarios-atka: Collection of shapefiles that depict the modeled potential maximum inundation by tsunami waves for each modeled scenario. Detailed information about each scenario can be found in the accompanying report. Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 2015 Ending_Date: 2019 Currentness_Reference: publication date Status: Progress: complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -176.674276 East_Bounding_Coordinate: -174.169057 North_Bounding_Coordinate: 52.237032 South_Bounding_Coordinate: 51.844269 Keywords: Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: geoscientificInformation Theme: Theme_Keyword_Thesaurus: Alaska Division of Geological & Geophysical Surveys Theme_Keyword: Bathymetry Theme_Keyword: Coastal Theme_Keyword: Coastal and River Theme_Keyword: Earthquake Theme_Keyword: Emergency Preparedness Theme_Keyword: Engineering Theme_Keyword: Engineering Geology Theme_Keyword: Environmental Theme_Keyword: Fault Displacement Theme_Keyword: Faulting Theme_Keyword: Faults Theme_Keyword: Flood Theme_Keyword: Geologic Theme_Keyword: Geologic Hazards Theme_Keyword: Geological Process Theme_Keyword: Geology Theme_Keyword: Geotechnical Theme_Keyword: Hazards Theme_Keyword: Inundation Theme_Keyword: Marine Geology Theme_Keyword: Modeling Theme_Keyword: Neotectonics Theme_Keyword: Seismic Hazards Theme_Keyword: Surface Theme_Keyword: Tectonics Theme_Keyword: Tides Theme_Keyword: Topography Theme_Keyword: Tsunami Place: Place_Keyword_Thesaurus: Alaska Division of Geological & Geophysical Surveys Place_Keyword: Adak Place_Keyword: Aleutian Islands Place_Keyword: Atka Access_Constraints: This report, map, and/or dataset is available directly from the State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys (see contact information below). Use_Constraints: Any hard copies or published datasets utilizing these datasets shall clearly indicate their source. If the user has modified the data in any way, the user is obligated to describe the types of modifications the user has made. The user specifically agrees not to misrepresent these datasets, nor to imply that changes made by the user were approved by the State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys. The State of Alaska makes no express or implied warranties (including warranties for merchantability and fitness) with respect to the character, functions, or capabilities of the electronic data or products or their appropriateness for any user's purposes. In no event will the State of Alaska be liable for any incidental, indirect, special, consequential, or other damages suffered by the user or any other person or entity whether from the use of the electronic services or products or any failure thereof or otherwise. In no event will the State of Alaska's liability to the Requestor or anyone else exceed the fee paid for the electronic service or product. Point_of_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: Alaska Division of Geological & Geophysical Surveys Contact_Position: Metadata Manager Contact_Address: Address_Type: mailing and physical Address: 3354 College Road City: Fairbanks State_or_Province: AK Postal_Code: 99709-3707 Country: USA Contact_Voice_Telephone: (907)451-5020 Contact_Facsimile_Telephone: (907)451-5050 Contact_Electronic_Mail_Address: dggspubs@alaska.gov Hours_of_Service: 8 am to 4:30 pm, Monday through Friday, except State holidays Data_Set_Credit: This report was funded by Award NA15NWS4670027 by a National Tsunami Hazard Mitigation Program grant to the Alaska Division of Homeland Security and Emergency Management and University of Alaska Fairbanks from the Department of Commerce/National Oceanic at Atmospheric Administration. This does not constitute an endorsement by NOAA. Numerical calculations for this work were supported by High-Performance Computing (HPC) resources at the Research Computing Systems unit at the Geophysical Institute, University of Alaska Fairbanks. We are grateful to Jonathan Allan and Richard Koehler for their valuable comments and suggestions that helped improve the report. Cross_Reference: Citation_Information: Originator: Nicolsky, D.J. Originator: Suleimani, E.N. Originator: Koehler, R.D. Publication_Date: 2016 Title: Tsunami inundation map for the village of Nikolski, Alaska Series_Information: Series_Name: Report of Investigation Issue_Identification: RI 2016-7 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 34 p., 1 sheet, scale 1:12,500 Online_Linkage: http://doi.org/10.14509/29674 Cross_Reference: Citation_Information: Originator: Nicolsky, D.J. Originator: Suleimani, E.N. Originator: Koehler, R.D. Publication_Date: 2017 Title: Tsunami inundation maps for the city of Sand Point, Alaska Series_Information: Series_Name: Report of Investigation Issue_Identification: RI 2017-3 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 61 p., 4 sheets, scale 1:15,000 Online_Linkage: http://doi.org/10.14509/29706 Cross_Reference: Citation_Information: Originator: Suleimani, E.N. Originator: Nicolsky, D.J. Originator: Koehler, R.D. Originator: Freymueller, J.T. Originator: Macpherson, A.E. Publication_Date: 2016 Title: Tsunami inundation maps for King Cove and Cold Bay communities, Alaska Series_Information: Series_Name: Report of Investigation Issue_Identification: RI 2016-1 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 73 p., 2 sheets, scale 1:12,500 Online_Linkage: http://doi.org/10.14509/29565 Cross_Reference: Citation_Information: Originator: Suleimani, E.N. Originator: Nicolsky, D.J. Originator: Koehler, R.D. Originator: Salisbury, J.B. Publication_Date: 2018 Title: Regional tsunami hazard assessment for Andreanof Islands, Alaska Series_Information: Series_Name: Report of Investigation Issue_Identification: RI 2017-2 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 19 p., 2 sheets Online_Linkage: http://doi.org/10.14509/29704 Cross_Reference: Citation_Information: Originator: Suleimani, E.N. Originator: Salisbury, J.B. Originator: Nicolsky, D.J. Originator: Koehler, R.D. Publication_Date: 2019 Title: Regional tsunami hazard assessment for Shemya, Alaska Series_Information: Series_Name: Report of Investigation Issue_Identification: RI 2019-4 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 13 p., 1 sheet Online_Linkage: http://doi.org/10.14509/30193 Cross_Reference: Citation_Information: Originator: Suleimani, E.N. Originator: Salisbury, J.B. Originator: Nicolsky, D.J. Originator: Koehler, R.D. Publication_Date: 2019 Title: Regional tsunami hazard assessment for False Pass and Perryville, Alaska Series_Information: Series_Name: Report of Investigation Issue_Identification: RI 2019-3 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 16 p., 2 sheets Online_Linkage: http://doi.org/10.14509/30192 Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: The hydrodynamic model used to calculate propagation and runup of tectonic tsunamis is a nonlinear, flux-formulated, shallow-water model and has passed the required tests for official use in producing tsunami inundation maps. Most of the uncertainties in the numerical calculations originate from the tsunamigenic earthquake sources used in the models. Uncertainties in the earthquakes, such as the precise location, magnitude, and slip distribution, are the largest sources of error. The direction, amplitude, and arrival times of incoming waves are determined by the initial ocean surface conditions immediately following the earthquake. Therefore, the modeling results are particularly sensitive to the details of the tsunamigenic earthquake rupture, and when the earthquake occurs close to a community, discrepancies can be exacerbated. Furthermore, our assessment of potential earthquake scenarios is by no means exhaustive but represents the best estimate of the locations and sizes of potential tsunami-generating events. It is possible that other unrecognized earthquake scenarios could present hazards to these communities. This DGGS Report of Investigations is a final report of scientific research. Several scientists familiar with the subject matter provided technical reviews. Uncertainties associated with the depiction or interpretation of various features are discussed in the manuscript. Logical_Consistency_Report: Not applicable Completeness_Report: The results of our modeling have been completed using the best information available and are believed to be accurate; however, their preparation required many assumptions and actual conditions during a tsunami event may vary from those considered. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: We use a series of nested computational grids to calculate inundation with a sufficiently high resolution for each community. The bathymetry and topography in each nested grid are based on digital elevation models (DEMs) developed at the National Centers for Environmental Information (NCEI) of the National Oceanic & Atmospheric Administration (NOAA). The spatial resolution of these high-resolution grids, with about 28 × 27 m (92 × 88 ft) cells, satisfies the NOAA minimum recommended requirements for computation of tsunami inundation. See the accompanying report for more detail and additional information. Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: The vertical accuracy of the inundation modeling is dependent on the accuracy and resolution of the digital elevation models (DEMs) and tidal datum values that were used to compile the computational grid. We provide additional details about DEM and grid development in the accompanying report. Prior to scenario modeling, bathymetric data were shifted to use Mean Higher High Water (MHHW) as the vertical datum. The depths of inundation shown should be used only as a guideline for emergency planning and response action. Actual inundation water depth will depend on specifics of the earth deformations, on-land construction, and tide level, and they may differ from areas shown by this data. The information is intended to permit state and local agencies to plan emergency evacuation and tsunami response actions in the event of a major tsunamigenic earthquake. These results are not intended for land-use regulation or building-code development. For additional information please reference the sources of errors and uncertainties section of the associated manuscript. Lineage: Process_Step: Process_Description: Model validation - The numerical model that we used for simulation of tsunami wave propagation and runup was validated through a set of analytical benchmarks and tested against laboratory data. The model solves water equations using a finite-difference method on a staggered grid. See the accompanying report for more detail and additional model information. Process_Date: 2011 Process_Step: Process_Description: Development of nested grids - To support inundation modeling of coastal areas in Alaska, we used a series of nested telescoping grids, or digital elevation models (DEMs), as input layers for tsunami inundation modeling and mapping. These grids of increasing resolution allowed us to propagate waves generated by various sources to Adak and Atka. In order to propagate a wave from its source to various coastal locations, we used embedded grids, placing a large, coarse grid in deep water and coupling it with smaller, finer grids in shallow water areas. The extent of each grid used for our tsunami inundation mapping is listed in the accompanying report. To minimize the vertical error resulting from conversion of the DCRA datum to the Mean Higher High Water (MHHW) datum, we augment our topographic dataset with elevations collected by a real-time kinematic (RTK) survey-grade Leica 500 Global Positioning System (GPS). See Methodology and Data section of the accompanying report for more detail and additional grid development source information. Process_Date: 2015 Process_Step: Process_Description: Numerical simulations of hypothetical tsunami scenarios - We assessed hazards related to tectonic tsunamis in Adak and Atka by performing model simulations for each hypothetical source scenario. Numerical results for each scenario include extent of inundation, sea level and velocity time series calculations, tsunami flow depth over land, and the maximum water level above the MHHW tide level offshore and within the potential inundation area. We create raster files of model results. For each grid point, the pixel value provides the modeled depth of water (in meters). See the accompanying report for more detail and additional information. Process_Date: 2015 Process_Step: Process_Description: Calculation of the potential inundation lines - For each grid cell in the high-resolution DEMs encompassing Adak and Atka, we determined whether the cell was inundated by waves or stayed dry throughout the entire simulation. Then, we defined a function such that it is equal to one at the center of each wet cell and is negative one at the center of each dry cell. Using a linear interpolation algorithm in Matlab, we plotted a zero-value contour that delineates dry and wet cells from each other. The resultant contour line (or a collection of lines) was directly exported to the ArcGIS using WGS84 datum. Process_Date: 2015 Process_Step: Process_Description: Compilation of composite maximum inundation zone, flow depths over land, and water level above the MHHW tide level offshore and within the potential inundation area - We interpret the maximum, geologically credible, worst-case scenario by combining the maximum calculated inundation of all scenarios. See the accompanying report for more detail and additional information. Process_Date: 2015 Process_Step: Process_Description: To create a shapefile for the post-earthquake shoreline resulted from coseismic subsidence - we calculated the amount of coseismic ground subsidence in the community for each scenario considered in the report and select the largest value among all scenarios. Then we subtracted this amount from the community DEM used to model tsunami inundation and calculated the new shoreline position from the boundary between positive (land) and negative (water) values using Matlab. Process_Date: 2015 Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: vector Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Geographic: Latitude_Resolution: .000001 Longitude_Resolution: .000001 Geographic_Coordinate_Units: decimal degrees Geodetic_Model: Horizontal_Datum_Name: World Geodetic System of 1984 Ellipsoid_Name: WGS 84 Semi-major_Axis: 6378137 Denominator_of_Flattening_Ratio: 298.257223563000025 Vertical_Coordinate_System_Definition: Depth_System_Definition: Depth_Datum_Name: Mean Higher High Water Depth_Resolution: 1 Depth_Distance_Units: meter Depth_Encoding_Method: Attribute values Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: ri2019-1-max-flow-depth-adak.tif, ri2019-1-max-flow-depth-atka.tif Entity_Type_Definition: Raster image depicting maximum composite flow depths over dry land. For each grid point, the pixel value provides the modeled depth of water (in meters) over previously dry land, representing the maximum depth value of all calculated tsunami scenarios. File format: GeoTIFF Entity_Type_Definition_Source: Alaska Earthquake Center, Geophysical Institute, University of Alaska, this report Entity_Attribute_Layer_Name: max-flow-depth Detailed_Description: Entity_Type: Entity_Type_Label: ri2019-1-max-inundation-adak.shp, ri2019-1-max-inundation-atka.shp Entity_Type_Definition: Estimated, "maximum credible scenario" inundation line(s) that encompasses the maximum extent of flooding based on model simulation of all credible source scenarios and historical observations. The maximum credible scenario inundation lines are intended to be utilized as a basis for local tsunami hazard planning and development of evacuation maps. File format: shapefile Entity_Type_Definition_Source: Alaska Earthquake Center, Geophysical Institute, University of Alaska, this report Entity_Attribute_Layer_Name: max-inundation Detailed_Description: Entity_Type: Entity_Type_Label: ri2019-1-mhhw-shoreline-adak.shp, ri2019-1-mhhw-shoreline-atka.shp Entity_Type_Definition: MHHW (Mean Higher High Water) shoreline of the map area. The shoreline position is calculated from the boundary between positive (land) and negative (water) values in the supporting DEM. File format: shapefile Entity_Type_Definition_Source: Alaska Earthquake Center, Geophysical Institute, University of Alaska, this report Entity_Attribute_Layer_Name: mhhw-shoreline Detailed_Description: Entity_Type: Entity_Type_Label: ri2019-1-post-earthquake-shoreline-adak.shp, ri2019-1-post-earthquake-shoreline-atka.shp Entity_Type_Definition: The post-earthquake shoreline that corresponds to MHHW after modeled coseismic ground changes due to earthquakes. File format: shapefile Entity_Type_Definition_Source: Alaska Earthquake Information Center, Geophysical Institute, University of Alaska, this report Entity_Attribute_Layer_Name: post-earthquake-shoreline Detailed_Description: Entity_Type: Entity_Type_Label: ri2019-1-scenario-01-adak.shp, ri2019-1-scenario-02-adak.shp, ri2019-1-scenario-03-adak.shp, ri2019-1-scenario-04-adak.shp, ri2019-1-scenario-05-adak.shp, ri2019-1-scenario-06-adak.shp, ri2019-1-scenario-07-adak.shp, ri2019-1-scenario-08-adak.shp, ri2019-1-scenario-09-adak.shp Entity_Type_Definition: Collection of shapefiles that depict the modeled potential maximum inundation by tsunami waves for each modeled scenario. Detailed information about each scenario can be found in the accompanying report. File format: shapefile Entity_Type_Definition_Source: Alaska Earthquake Information Center, Geophysical Institute, University of Alaska, this report Entity_Attribute_Layer_Name: scenarios-adak Detailed_Description: Entity_Type: Entity_Type_Label: ri2019-1-scenario-01-atka.shp, ri2019-1-scenario-02-atka.shp, ri2019-1-scenario-03-atka.shp, ri2019-1-scenario-04-atka.shp, ri2019-1-scenario-05-atka.shp, ri2019-1-scenario-06-atka.shp, ri2019-1-scenario-07-atka.shp, ri2019-1-scenario-08-atka.shp, ri2019-1-scenario-09-atka.shp Entity_Type_Definition: Collection of shapefiles that depict the modeled potential maximum inundation by tsunami waves for each modeled scenario. Detailed information about each scenario can be found in the accompanying report. File format: shapefile Entity_Type_Definition_Source: Alaska Earthquake Information Center, Geophysical Institute, University of Alaska, this report Entity_Attribute_Layer_Name: scenarios-atka Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: Alaska Division of Geological & Geophysical Surveys Contact_Position: Metadata Manager Contact_Address: Address_Type: mailing and physical Address: 3354 College Road City: Fairbanks State_or_Province: AK Postal_Code: 99709-3707 Country: USA Contact_Voice_Telephone: (907)451-5020 Contact_Facsimile_Telephone: (907)451-5050 Contact_Electronic_Mail_Address: dggspubs@alaska.gov Hours_of_Service: 8 am to 4:30 pm, Monday through Friday, except State holidays Resource_Description: RI 2019-1 Distribution_Liability: The State of Alaska makes no expressed or implied warranties (including warranties for merchantability and fitness) with respect to the character, functions, or capabilities of the electronic data or products or their appropriateness for any user's purposes. In no event will the State of Alaska be liable for any incidental, indirect, special, consequential, or other damages suffered by the user or any other person or entity whether from the use of the electronic services or products or any failure thereof or otherwise. In no event will the State of Alaska's liability to the Requestor or anyone else exceed the fee paid for the electronic service or product. Standard_Order_Process: Non-digital_Form: DGGS publications are available as free online downloads or you may purchase paper hard-copies or digital files on CD/DVD or other digital storage media by mail, phone, fax, or email from the DGGS Fairbanks office. To purchase this or other printed reports and maps, contact DGGS by phone (907-451-5020), e-mail (dggspubs@alaska.gov), or fax (907-451-5050). Payment accepted: Cash, check, money order, VISA, or MasterCard. Turnaround time is 1-2 weeks unless special arrangements are made and an express fee is paid. 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Fees: Contact DGGS for current pricing Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: Shapefiles, Raster data Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: http://doi.org/10.14509/30186 Fees: Free download Metadata_Reference_Information: Metadata_Date: 20191007 Metadata_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: Alaska Division of Geological & Geophysical Surveys Contact_Person: Simone Montayne Contact_Position: Metadata Manager Contact_Address: Address_Type: mailing and physical Address: 3354 College Road City: Fairbanks State_or_Province: AK Postal_Code: 99709-3707 Country: USA Contact_Voice_Telephone: (907)451-5020 Contact_Facsimile_Telephone: (907)451-5050 Contact_Electronic_Mail_Address: dggspubs@alaska.gov Hours_of_Service: 8 am to 4:30 pm, Monday through Friday, except State holidays Metadata_Standard_Name: FGDC Content Standard for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998 Metadata_Use_Constraints: If the user has modified the data in any way they are obligated to describe the types of modifications they have performed in the supporting metadata file. User specifically agrees not to imply that changes they made were approved by the Alaska Department of Natural Resources or Division of Geological & Geophysical Surveys. Metadata_Extensions: Online_Linkage: http://www.dggs.alaska.gov/metadata/dggs.ext Profile_Name: dggs metadata extensions