Identification_Information: Citation: Citation_Information: Originator: Wolken, G.J. Originator: Fischer, Elizabeth Originator: Hendricks, M.D. Originator: Wikstrom Jones, K.M. Publication_Date: 2026 Title: Alaska Snow Avalanche Hazards Database Geospatial_Data_Presentation_Form: data Series_Information: Series_Name: Digital Data Series Issue_Identification: DDS 26 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 7 p. Online_Linkage: https://doi.org/10.14509/32076 Description: Abstract: Alaska Snow Avalanche Hazards Database, Digital Data Series 26, is a statewide geospatial archive that systematically stores, organizes, and shares snow avalanche hazard information. It is designed to hold standardized raster and vector layers describing snow and terrain conditions, potential release areas, simulated avalanche extents, and derived hazard indication data. The structure emphasizes repeatable, map-based workflows that can be applied consistently across regions and scales, from broad hazard indication assessments to path-specific analyses. Modular and updateable, the database can incorporate new avalanche datasets as they become available. Its primary goal is to serve as a centralized repository of snow avalanche hazard information that supports evidence-based decision-making for land-use planning, transportation, resource management, and risk-reduction efforts. These data and accompanying discussion are released as a DGGS Digital Data Series publication, and all publication components are available from the DGGS website at https://doi.org/10.14509/3207632076. Purpose: The Alaska Snow Avalanche Hazards Database centralizes standardized data layers that describe snow and terrain conditions, potential release areas, and modeled avalanche extents for Alaska, where steep terrain, deep snowpacks, and exposed communities and transportation corridors make avalanches a recurring hazard. It supports evidence-based land-use planning, transportation, resource management, and risk-reduction decisions across avalanche-prone areas of the state, particularly where field-based hazard mapping is limited. Supplemental_Information: The Alaska Snow Avalanche Hazards Database is not suitable for answering site-specific or legal questions and should only be used for regional- or community-scale purposes. Maps generated from the database should not be viewed at scales finer than those specified in the original data sources, and all limitations of the original publications apply to this database. >avalanche_hazard_deposition: Modeled depth of snow deposited by avalanches, in meters (m). Available for four scenarios: Frequent Historical (1981-2010), Rare Historical (1981-2010), Frequent Future, and Rare Future. Frequent scenarios have an estimated return period of less than 30 years, and rare scenarios have an estimated return period between 30 and 300 years. Historical scenarios represent climate conditions from 1981 to 2010, and future scenarios represent projected future climate conditions. >avalanche_hazard_max_pressure: Modeled maximum impact pressure of avalanches, in kilopascals (kPa). Available for four scenarios: Frequent Historical (1981-2010), Rare Historical (1981-2010), Frequent Future, and Rare Future. Frequent scenarios have an estimated return period of less than 30 years, and rare scenarios have an estimated return period between 30 and 300 years. Historical scenarios represent climate conditions from 1981 to 2010, and future scenarios represent projected future climate conditions. >avalanche_hazard_extent: A simple extent of the modeled avalanche area. Available for four scenarios: Frequent Historical (1981-2010), Rare Historical (1981-2010), Frequent Future, and Rare Future. Frequent scenarios have an estimated return period of less than 30 years, and rare scenarios have an estimated return period between 30 and 300 years. Historical scenarios represent climate conditions from 1981 to 2010, and future scenarios represent projected future climate conditions. Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 2026 Currentness_Reference: publication date Status: Progress: Planned Maintenance_and_Update_Frequency: Irregular Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -180.000000 East_Bounding_Coordinate: 180.000000 North_Bounding_Coordinate: 71.392029 South_Bounding_Coordinate: 51.217293 Keywords: Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: geoscientificInformation Theme: Theme_Keyword_Thesaurus: Alaska Division of Geological & Geophysical Surveys Theme_Keyword: Avalanche Theme_Keyword: Climate Theme_Keyword: Coastal Theme_Keyword: Coastal and River Theme_Keyword: Database Theme_Keyword: DGGS Theme_Keyword: Emergency Preparedness Theme_Keyword: Geologic Theme_Keyword: Geologic Hazards Theme_Keyword: Geological Process Theme_Keyword: Geology Theme_Keyword: Geomorphology Theme_Keyword: Hazards Theme_Keyword: Methods Theme_Keyword: Modeling Theme_Keyword: Mountain Theme_Keyword: Remote Sensing Theme_Keyword: Repeat Data Collection Theme_Keyword: Slope Theme_Keyword: Slope Instability Theme_Keyword: Snow Avalanche Theme_Keyword: Snow Depth Theme_Keyword: Topography Theme_Keyword: Transportation Theme_Keyword: Transportation Corridor Place: Place_Keyword_Thesaurus: Alaska Division of Geological & Geophysical Surveys Place_Keyword: Admiralty Island Place_Keyword: Alaska Place_Keyword: Alaska, State of Place_Keyword: Chilkat Pass Place_Keyword: Chilkoot Pass Place_Keyword: Haines Place_Keyword: Haines Highway Place_Keyword: Hyder Place_Keyword: Juneau Place_Keyword: Klondike Highway Place_Keyword: Skagway Place_Keyword: Southeast Alaska Place_Keyword: White Pass 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 Contact_Instructions: Please view our website (https://www.dggs.alaska.gov) for the latest information on available data. Please contact us using the e-mail address provided above when possible. Data_Set_Credit: This project was funded by the U.S. Geological Survey Alaska Climate Adaptation Science Center (Grant Number G21AC10867). We gratefully acknowledge the many avalanche safety practitioners and scientists who contributed their time and expertise to reviewing this work and informing the development of the Alaska Snow Avalanche Hazards Database. The views and conclusions contained in this publication are those of the authors and do not necessarily represent the opinions or policies of the U.S. Government. Mention of trade names or commercial products does not constitute their endorsement by the U.S. Government. This report and database are submitted for publication with the understanding that the U.S. Government is authorized to reproduce and distribute reprints for governmental purposes. Cross_Reference: Citation_Information: Originator: Wikstrom Jones, K.M. Originator: Wolken, G.J. Originator: Janes, Michael Originator: Wilbur, Chris Originator: Glaus, Julia Originator: Bartelt, Perry Originator: Christen, Marc Publication_Date: 2023 Title: Assessing powder cloud impact on electrical transmission lines at Snowslide Creek avalanche path in Southeast Alaska (poster): International Snow Science Workshop, Bend, Oregon, October 8-13, 2023 Series_Information: Series_Name: Poster and Presentation Issue_Identification: Wikstrom Jones, K.M. and others, 2023 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 1 sheet Online_Linkage: https://doi.org/10.14509/32167 Cross_Reference: Citation_Information: Originator: Wikstrom Jones, Katreen Originator: Wolken, G.J. Originator: Janes, Michael Publication_Date: 2026 Title: From point to slope: Assessing weather station snow depth representativeness using lidar and geostatistics (poster): International Snow Science Workshop, Whistler, BC, Canada, September 28-Oct 2, 2026 Series_Information: Series_Name: Poster and Presentation Issue_Identification: Wikstrom Jones, Katreen and others, 2026 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 1 sheet Online_Linkage: https://doi.org/10.14509/32166 Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: The model outputs have not been calibrated or validated against observed avalanche events because Alaska lacks a long-term, spatially extensive avalanche incident database, so accuracy is untested and the results carry substantial uncertainty from coarse terrain, land cover, and downscaled climate inputs. The maps are best used as first-order, regional- to community-scale hazard indicators where field-based assessments are not feasible. Logical_Consistency_Report: All layers were produced with the same methods and a common grid resolution and merged into continuous maps, with only minor processing artifacts that have little effect on the final hazard layers. Completeness_Report: The database currently covers only parts of Alaska. It does not include observed avalanche events, some avalanche types (such as powder and wet-snow avalanches), or certain release mechanisms. Fine-scale terrain, weather, and land cover information is also limited. Additional regions and refined datasets will be added as they become available. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: Locations are based on a 10 m grid derived from the USGS 5 m IFSAR elevation model, so positional detail is limited to roughly that resolution, and coarser inputs such as 30 m land cover and 4 km climate data further reduce local precision. No formal horizontal accuracy assessment was performed, and the maps should not be used at scales finer than the original data sources support. Lineage: Process_Step: Process_Description: Database deployment - The first iteration of the database focuses on regional, model-based hazard indication products for Southcentral and Southeast Alaska (roughly from the central Chugach Mountains to Alaska's southeastern border). The hazard map layers were produced following the methods of Buhler and others (2022) and used three main inputs. Terrain came from the USGS Alaska IFSAR digital elevation model, resampled from 5 m to 10 m. A forest mask from the 2016 National Land Cover Database identified protective evergreen forest, where avalanches could not start. Extreme snowfall was estimated from 1981-2010 reanalysis data, dynamically downscaled to 4 km with the Weather Research and Forecasting model and then to 10 m using a constant lapse rate. Potential release areas were mapped from terrain derivatives and the forest mask for Frequent (about 30-year) and Rare (about 300-year) scenarios. They were sorted into four size classes to set friction parameters, using area rather than release volume as a deviation from Buhler and others (2022). The RAMMS::LSHIM model was then run for each release area across four 30 km tiles. Avalanche extents were defined as areas with flow depth above 0.25 m and velocity above 1 m s^-1. Results were filtered to remove unrealistic low-elevation avalanches caused by land cover misclassification, and the tiles were merged into continuous hazard layers. Process_Date: 2026 Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: raster Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Planar: Map_Projection: Map_Projection_Name: Web Mercator Mercator: Standard_Parallel: 0.0 Longitude_of_Central_Meridian: 0.0 False_Easting: 0 False_Northing: 0 Planar_Coordinate_Information: Planar_Coordinate_Encoding_Method: coordinate pair Coordinate_Representation: Abscissa_Resolution: 10 Ordinate_Resolution: 10 Planar_Distance_Units: meters Geodetic_Model: Horizontal_Datum_Name: WGS84 Ellipsoid_Name: WGS 84 Semi-major_Axis: 6378137 Denominator_of_Flattening_Ratio: 298.257223563 Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: avalanche_hazard_deposition Entity_Type_Definition: Modeled depth of snow deposited by avalanches, in meters (m). Available for four scenarios: Frequent Historical (1981-2010), Rare Historical (1981-2010), Frequent Future, and Rare Future. Frequent scenarios have an estimated return period of less than 30 years, and rare scenarios have an estimated return period between 30 and 300 years. Historical scenarios represent climate conditions from 1981 to 2010, and future scenarios represent projected future climate conditions. Entity_Type_Definition_Source: this report, DGGS staff Entity_Attribute_Layer_Name: avalanche_hazard_deposition Detailed_Description: Entity_Type: Entity_Type_Label: avalanche_hazard_max_pressure Entity_Type_Definition: Modeled maximum impact pressure of avalanches, in kilopascals (kPa). Available for four scenarios: Frequent Historical (1981-2010), Rare Historical (1981-2010), Frequent Future, and Rare Future. Frequent scenarios have an estimated return period of less than 30 years, and rare scenarios have an estimated return period between 30 and 300 years. Historical scenarios represent climate conditions from 1981 to 2010, and future scenarios represent projected future climate conditions. Entity_Type_Definition_Source: this report, DGGS staff Entity_Attribute_Layer_Name: avalanche_hazard_max_pressure Detailed_Description: Entity_Type: Entity_Type_Label: avalanche_hazard_extent Entity_Type_Definition: A simple extent of the modeled avalanche area. Available for four scenarios: Frequent Historical (1981-2010), Rare Historical (1981-2010), Frequent Future, and Rare Future. Frequent scenarios have an estimated return period of less than 30 years, and rare scenarios have an estimated return period between 30 and 300 years. Historical scenarios represent climate conditions from 1981 to 2010, and future scenarios represent projected future climate conditions. Entity_Type_Definition_Source: this report, DGGS staff Entity_Attribute_Layer_Name: avalanche_hazard_extent 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 Contact_Instructions: Please view our website (https://www.dggs.alaska.gov) for the latest information on available data. Please contact us using the e-mail address provided above when possible. Resource_Description: DDS 26 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. Shipping charge will be the actual cost of postage and will be added to the total amount due. Contact us for the exact shipping amount. Fees: Contact DGGS for current pricing Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: database Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: https://doi.org/10.14509/32076 Fees: Free download Metadata_Reference_Information: Metadata_Date: 20261016 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: https://dggs.alaska.gov/metadata/dggs.ext Profile_Name: dggs metadata extensions