Vectorized Lead Segmentation covering the Chukchi and Beaufort Seas offshore of Northern Alaska, USA and Northwest Canada.

Metadata also available as

Metadata:


Identification_Information:
Citation:
Citation_Information:
Originator: University of Alaska Fairbanks
Publication_Date: 20051231
Title:
Vectorized Lead Segmentation covering the Chukchi and Beaufort Seas offshore of Northern Alaska, USA and Northwest Canada.
Geospatial_Data_Presentation_Form: vector digital data
Online_Linkage: <http://mms.gina.alaska.edu>
Description:
Abstract:
This vector based data set was derived from an ArcGIS grid (of 1.1 km cells) and represents spring leads along the coast of Northern Alaska (West of Barrow) and Northwest Canada (East of the Mackenzie Delta) for the study area which ranges from approximately 130 to 164 degrees West and 68.5 to 74 degrees North.
Purpose:
This data was compiled by the University of Alaska Fairbanks to meet contract requirements for the US Mineral Management Service: Mapping and Characterization of Recurring Spring Leads and Landfast ice in the Beaufort and Chukchi Seas (AK-03-06)
Supplemental_Information:
For the purposes of the MMS study, the file names associated with Band 1 data (visual) are prefixed with a "v" and Band 4 files (thermal) prefixed with a "t". The day of the year, hour and minutes are incorporated in the file names. For descriptive purposes the following abbreviations are used as placeholders for real values to illustrate the naming convention: d = day of year Y = Year T = time in GMT A Band 1 shapefile follows this convention: v d d d _T T T Tshape A Band 4 shapefile follows this convention: t d d d _T T T Tshape Examples of these file names are v015_1012shape and t015_1012shape
Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 197201
Ending_Date: unknown
Currentness_Reference: ground condition
Status:
Progress: In work
Maintenance_and_Update_Frequency: As needed
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -164.176389
East_Bounding_Coordinate: -129.978654
North_Bounding_Coordinate: 73.947199
South_Bounding_Coordinate: 68.481396
Keywords:
Theme:
Theme_Keyword_Thesaurus: Aquatic Sciences and Fisheries Thesaurus
Theme_Keyword: spring leads
Theme_Keyword: sea ice
Theme_Keyword: lead
Place:
Place_Keyword_Thesaurus: Dictionary of Alaska Place Names
Place_Keyword: Arctic Ocean
Place_Keyword: Chukchi Sea
Place_Keyword: Beaufort Sea
Place_Keyword: North Slope
Place_Keyword: Alaska
Place_Keyword: Canada
Access_Constraints: None.
Use_Constraints:
Any hardcopies or published information utilizing these data sets shall clearly indicate their source. If the user has modified the data in any way they are obligated to describe the types of modifications that they have performed. User specifically agrees not to misrepresent these datasets, nor to imply that any changes that they made were approved by the University of Alaska.
Point_of_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Dr. Hajo Eicken
Contact_Organization: Geophysical Institute
Contact_Position: Unversity of Alaska Fairbanks
Contact_Address:
Address_Type: mailing and physical address
Address: 903 Koyukuk Dr., P.O. Box 757320
City: Fairbanks
State_or_Province: Alaska
Postal_Code: 99775-7320
Country: USA
Contact_Voice_Telephone: 907-474-7280
Contact_Facsimile_Telephone: 907-474-7290
Contact_Electronic_Mail_Address: hajo.eicken@gi.alaska.edu
Browse_Graphic:
Browse_Graphic_File_Name: *.jpg
Browse_Graphic_File_Description: Low resolution browse graphic of shapefile
Browse_Graphic_File_Type: JPEG
Data_Set_Credit:
The funding for this effort was provided by the US Mineral Management Service for Mapping and Characterization of Recurring Spring Leads and Landfast ice in the Beaufort and Chukchi Seas (AK-03-06, MMS-71707)
Native_Data_Set_Environment:
Microsoft Windows 2000 Version 5.0 (Build 2195) Service Pack 4; ESRI ArcCatalog 8.3.0.800

Data_Quality_Information:
Logical_Consistency_Report:
Map projection and datum were confirmed and checked to conform with base data sets and imagery.
Completeness_Report: Complete.
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
The International Observatory of the North (ION) uses satellite navigation and attitude parameters for scene navigation (with additional ground control) to produce adequate results (with errors <3 km) for geolocated AVHRR imagery. ION data sets were used as a base map to derive the lead segmentation.
Quantitative_Horizontal_Positional_Accuracy_Assessment:
Horizontal_Positional_Accuracy_Value: 3000 meters
Horizontal_Positional_Accuracy_Explanation: Visual inspection. Distance measurement tools.
Lineage:
Process_Step:
Process_Description:
AVHRR data was geolocated, calibrated and reprojected in GeoTIFF format using TeraScan software. A coast mask is applied in ENVI. The fraction of leads within each pixel is then determined based on the brightness temperatures or reflectances of open water and the surrounding thick ice, as described by Lindsay and Rothrock (Arctic sea ice leads from advanced very high resolution radiometer images. Journal of Geophysical Research, 100(C3), 4533-4544, 1995). Here, we have corrected for regional differences in surface temperature and reflectance as well as thin cloud cover by determining the fraction of leads within a moving 50 by 50 pixel (55 x 55 km) square window, with the fraction of thick ice based on the upper and lower quartile reflectance and brightness temperature, respectively. For a few cases of more expansive stretches of open water, manual adjustments of open water extent have been made. The resulting image indicating the fraction of open water is then binarized about a threshold corresponding to an open water fraction of 25% in each pixel, with pixels containing less open water designated as ice and those at or above 25% designated as leads. This information is then brought into NIH Image for derivation of lead location, shape and size statistics, open water fractions and other information for the different study subregions.

An IDL script was used to export the binarized files into GeoTiff format. The batch utility within ArcToolbox was used to convert GeoTiffs to ArcGIS Grid format. A batch file was used in ArcCatalog to define the map projection and datum. Each Grid file was then converted to an ArcGIS Coverage file and then Shapefile using batch utilities within ArcToolbox. Low resolution browse images (*.jpg format) were generated for display on the project web site. Final processing included a batch import of the appropriate FGDC compliant metadata template. Final data sets were bundled with Winzip for posting to the web to ensure clean data transfer of the components of the shapefile, plus associated metadata record and browse image.

Process_Date: 2004
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Dr. Hajo Eicken
Contact_Organization: University of Alaska Fairbanks, Geophysical Institute
Contact_Position: Associate Professor
Contact_Address:
Address_Type: mailing and physical address
Address: 903 Koyukuk Dr., P.O. Box 757320
City: Fairbanks
State_or_Province: AK
Postal_Code: 99775-7320
Country: USA
Contact_Voice_Telephone: 907-474-7196
Contact_Facsimile_Telephone: 907-474-7290
Contact_Electronic_Mail_Address: Hajo.Eicken@gi.alaska.edu
Hours_of_Service: business hours

Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Vector
Point_and_Vector_Object_Information:
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type: G-polygon
Point_and_Vector_Object_Count: 1564

Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Planar:
Map_Projection:
Map_Projection_Name: Albers Conical Equal Area
Albers_Conical_Equal_Area:
Standard_Parallel: 55.000000
Standard_Parallel: 65.000000
Longitude_of_Central_Meridian: -154.000000
Latitude_of_Projection_Origin: 50.000000
False_Easting: 0.000000
False_Northing: 0.000000
Planar_Coordinate_Information:
Planar_Coordinate_Encoding_Method: coordinate pair
Coordinate_Representation:
Abscissa_Resolution: 0.002048
Ordinate_Resolution: 0.002048
Planar_Distance_Units: meters
Geodetic_Model:
Horizontal_Datum_Name: North American Datum of 1983
Ellipsoid_Name: Geodetic Reference System 80
Semi-major_Axis: 6378137.000000
Denominator_of_Flattening_Ratio: 298.257222

Entity_and_Attribute_Information:
Detailed_Description:
Entity_Type:
Entity_Type_Label: Spring Leads
Entity_Type_Definition: Band 1
Entity_Type_Definition_Source: ESRI
Attribute:
Attribute_Label: FID
Attribute_Definition: Feature ID of shapefile
Attribute_Definition_Source: ESRI
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: FID
Enumerated_Domain_Value_Definition: Feature Identifier of Shapefile
Enumerated_Domain_Value_Definition_Source: ESRI
Attribute:
Attribute_Label: Shape
Attribute_Definition: Feature Class
Attribute_Definition_Source: ESRI
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: Shape
Enumerated_Domain_Value_Definition: Feature Class = Polygon
Enumerated_Domain_Value_Definition_Source: ESRI
Attribute:
Attribute_Label: Area
Attribute_Definition: Area of polygon
Attribute_Definition_Source: ESRI
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: Area
Enumerated_Domain_Value_Definition: Area of Polygon
Enumerated_Domain_Value_Definition_Source: Automatically calculated by ArcGIS
Attribute:
Attribute_Label: PERIMETER
Attribute_Definition: perimeter of polygon
Attribute_Definition_Source: ESRI
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: Perimeter
Enumerated_Domain_Value_Definition: Perimeter of polygon
Enumerated_Domain_Value_Definition_Source: Automatically calculated by ArcGIS
Attribute:
Attribute_Label: _#######
Attribute_Definition: Internal Feature Number
Attribute_Definition_Source: ESRI
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: _######
Enumerated_Domain_Value_Definition: Internal Feature Number
Enumerated_Domain_Value_Definition_Source: Residual Attribute Generated by conversion to ArcGIS Coverage
Attribute:
Attribute_Label: ######_ID
Attribute_Definition: Internal Identifier
Attribute_Definition_Source: ESRI
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: ######_ID
Enumerated_Domain_Value_Definition: Internal Identifier
Enumerated_Domain_Value_Definition_Source: Residual Attribute Generated by conversion to ArcGIS Coverage
Attribute:
Attribute_Label: GRID_CODE
Attribute_Definition: Grid code for cell value
Attribute_Definition_Source: ESRI
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: Value = 255
Enumerated_Domain_Value_Definition: ice
Enumerated_Domain_Value_Definition_Source: Derived from binary classification of AVHRR source imagery.
Enumerated_Domain:
Enumerated_Domain_Value: Value = 0
Enumerated_Domain_Value_Definition: leads
Enumerated_Domain_Value_Definition_Source: Binarized classification of AVHRR source imagery.

Distribution_Information:
Distributor:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: UAF Geographic Information Network of Alaska (GINA)
Contact_Person: Dr. Virgil (Buck) Sharpton
Contact_Position: President's Professor of Remote Sensing
Contact_Address:
Address_Type: mailing and physical address
Address: 903 Koyukuk Drive
City: Fairbanks
State_or_Province: Alaska
Postal_Code: 99775-7320
Country: USA
Contact_Voice_Telephone: 907.474.6663
Contact_Electronic_Mail_Address: buck.sharpton@gina.alaska.edu
Hours_of_Service: 8:00 a.m. - 5:00 p.m. AST
Resource_Description: Downloadable Data
Distribution_Liability:
The University of Alaska makes no express or implied warranties (including warranties of merchantability and fitness) with respect to the character, function, or capabilities of the electronic services or products or their appropriateness for any users purposes. In no event will the University 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, any failure thereof or otherwise, and 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:
Digital_Form:
Digital_Transfer_Information:
Format_Name: ESRI ArcGIS format
Format_Version_Date: 200301101
Format_Specification: ESRI Grid / ESRI Shapefile
Transfer_Size: 0.826
Digital_Transfer_Option:
Online_Option:
Computer_Contact_Information:
Network_Address:
Network_Resource_Name: <http://mms.gina.alaska.edu>
Access_Instructions: web browser and/or FTP
Fees: None
Available_Time_Period:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: unknown
Ending_Date: unknown

Metadata_Reference_Information:
Metadata_Date: 20040915
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: Nuna Technologies
Contact_Person: Allison Graves Gaylord
Contact_Position: Owner / GIS Specialist
Contact_Address:
Address_Type: mailing address
Address: P.O. Box 1483
City: Homer
State_or_Province: AK
Postal_Code: 99723-1483
Country: USA
Contact_Voice_Telephone: 907.235.3476
Contact_Electronic_Mail_Address: nunatech@usa.net
Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998
Metadata_Time_Convention: local time
Metadata_Access_Constraints: None.
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 University of Alaska.
Metadata_Security_Information:
Metadata_Security_Classification_System: None.
Metadata_Security_Classification: Unclassified
Metadata_Security_Handling_Description: None.
Metadata_Extensions:
Online_Linkage: <http://www.esri.com/metadata/esriprof80.html>
Profile_Name: ESRI Metadata Profile

Generated by mp version 2.8.14 on Fri Aug 26 13:13:47 2005