Identification_Information: Citation: Citation_Information: Originator: Pacific Islands Benthic Habitat Mapping Center (PIBHMC), Coral Reef Ecosystem Division (CRED), Pacific Islands Fisheries Science Center (PIFSC), National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA) Publication_Date: 200606 Title: CRED Optical Validation Data at Laysan Island, 2004, to Support Benthic Habitat Mapping Geospatial_Data_Presentation_Form: Video imagery, track line navigation files, and log sheets Online_Linkage: http://www.soest.hawaii.edu/pibhmc/ Description: Abstract: Optical validation data were collected using a Tethered Optical Assessment Device (TOAD), an underwater sled equipped with an underwater digital video camera and lights. Data were collected at the Northwestern Hawaiian Islands, Laysan Island to support Benthic Habitat Mapping efforts. Purpose: This data provides optical observations that will be correlated with bathymetry and acoustic backscatter imagery to develop a benthic habitat map of Laysan Island. Refer to supplemental information for description of instrument and survey. Supplemental_Information: Laysan Island, located at 25.75N, 171.75W, is an isolated coral island. The island is the largest in the Northwestern Hawaiian Island with 4.11 sq. km of land area and an interior hypersaline lake. Its coral reef habitat is relatively small, including 57 sq. km of banks less than 100 m in depth. Optical validation data were collected using the Tethered Optical Assessment Device (TOAD), a sled equipped with underwater video camera and lights. These data are used to provide ground-truth validation that for benthic habitat maps based on multibeam echosounder surveys. Camera sled deployments were conducted at night, usually between 1800 and midnight. Each tow was usually limited to 20 minutes of bottom time at a given location in order to allow for more tows to be conducted in a given work area and thus increase the spatial distribution of the observations. The camera sled was deployed from lower arm of the starboard J-frame on the NOAA Ship Hi'ialakai. At each station the ship was positioned with the wind on the starboard side and drifted downwind; occasional light turns were applied to the ship's screws if necessary to reduce the ship's motion. The TOAD was lowered slowly to the bottom by the deck crew. The operator monitored a live video feed from the camera and began recording data on two video tape recorders. When the camera reached bottom the deck crew was notified by radio to stop lowering. The operator continued to monitor the vehicle and provided commands to raise or lower it to keep the camera just above the bottom. Equipment Description: The TOAD was deployed from the lower arm of the vessel's J-frame. The TOAD is a camera sled based on the Guildline MiniBat model 8820 tow body. The frame has been extensively modified from its original configuration and was configured with a single ROS model 54-00100-13 color underwater video camera and two 500 W DeepSea Power & Light model 710-0400601 underwater lights mounted on the original sled frame. The MiniBat pressure sensor and wing controller was also mounted on the frame but no wings were installed. Cable between the sled and the surface consisted of an underwater electrical cable (cable 1, blue in color) with a separate load-bearing line to support the sled frame. The electrical cable was clipped to the line at regular intervals upon deployment and removed upon recovery. The load-bearing line was led to the starboard capstan on the aft deck. All TOAD surface components were located in the Dry Lab in an equipment rack on the after bulkhead. After operations began we learned that the sled's pressure sensor was not working. Name & address of person collecting data: John Rooney NOAA IRC NMFS/PIFSC/CRED 1845 WASP Blvd., Building 176 Honolulu, HI 96818 Data Files: Video data were recorded on two video tape recorders. The position of the camera sled was recorded using Guildline MiniBat In-Tow data acquisition software. File naming convention: Each tow is given a name consisting of a 3-letter designator for the island area followed by a two-digit year and three-digit tow number. For example, during HI0401 the first tow was called LAY04001. Video tape labels, the navigation files (*.glo) and paper log forms are all annotated with the tow name. If the navigation file is edited during processing the file name has a suffix "a" added. For example, one of the navigation data files is named "LAY04001a.glo". Metadata were extracted from the navigation data and recorded to a file with the same name as the navigation file except that a file type of ".met" was appended; for example, "LAY04001a.glo.met" Time Correlation: All times are based on UTC. Two clocks were set manually synchronized prior to starting data collection; the clock in the video character generator that was used to annotate the video tape and the TOAD data acquisition computer clock was used to annotate the navigation (*.glo) files. These clocks were set to UTC at the beginning of each evening's operations and then compared to one another prior to (and during) each tow. There were problems maintaining synchronization of the TOAD computer clock during this cruise. See the problems section for a description. (Problems with data could be described here.) Resource Description: Digital video images that are geo-referenced to navigation files. Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 20040925 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: As needed Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -171.80946 East_Bounding_Coordinate: -171.72754 North_Bounding_Coordinate: 25.8806 South_Bounding_Coordinate: 25.81427 Keywords: Theme: Theme_Keyword_Thesaurus: NCEI Geoportal Filter Theme_Keyword: CoRIS_Metadata Theme: Theme_Keyword_Thesaurus: CRCP Project Theme_Keyword: Benthic Habitat Mapping and Characterization - Northwestern and Main Hawaiian Islands Theme_Keyword: 1217 Theme: Theme_Keyword_Thesaurus: CoRIS Theme Thesaurus Theme_Keyword: EARTH SCIENCE > Biosphere > Aquatic Habitat > Benthic Habitat Theme_Keyword: EARTH SCIENCE > Biosphere > Zoology > Corals > Reef Monitoring and Assessment > Mapping Theme_Keyword: EARTH SCIENCE > Biosphere > Zoology > Corals > Reef Monitoring and Assessment > Photographic Analysis > Videography Theme: Theme_Keyword_Thesaurus: None Theme_Keyword: Tethered Optical Assessment Device (TOAD) Theme_Keyword: Underwater video Theme_Keyword: HI0401 Theme: Theme_Keyword_Thesaurus: CoRIS Discovery Thesaurus Theme_Keyword: Visual Images > Habitats Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: environment Theme_Keyword: biota Place: Place_Keyword_Thesaurus: CoRIS Place Thesaurus Place_Keyword: OCEAN BASIN > Pacific Ocean > Central Pacific Ocean > Northwestern Hawaiian Islands > Laysan Island (25N171W0001) Place_Keyword: COUNTRY/TERRITORY > United States of America > Hawaii > Honolulu > Laysan Island (25N171W0001) Place_Keyword: OCEAN BASIN > Pacific Ocean > Central Pacific Ocean > Northwestern Hawaiian Islands (28N178W0000) Place_Keyword: COUNTRY/TERRITORY > United States of America > Hawaii > Honolulu > Northwestern Hawaiian Islands (28N178W0000) Place: Place_Keyword_Thesaurus: CoRIS Region Place_Keyword: NWHI Access_Constraints: None Use_Constraints: Please acknowledge the NOAA Coral Reef Ecosystem Division, Pacific Islands Fisheries Science Center as the source of this information. Point_of_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: Pacific Islands Benthic Habitat Mapping Center (PIBHMC), Coral Reef Ecosystem Division (CRED), Pacific Islands Fisheries Science Center (PIFSC), National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA) Contact_Person: John Rooney Contact_Address: Address_Type: mailing and physical address Address: NOAA IRC Address: NMFS/PIFSC/CRED Address: 1845 WASP Blvd., Building 176 City: Honolulu State_or_Province: HI Postal_Code: 96818 Contact_Voice_Telephone: 808 725-5360 Contact_Facsimile_Telephone: 808 725-5429 Contact_Electronic_Mail_Address: nmfs.pic.credinfo@noaa.gov Contact_Instructions: e-mail preferred Data_Set_Credit: Benthic Habitat Mapping Group, Coral Reef Ecosystem Division (CRED), Pacific Islands Fisheries Science Center (PIFSC), NOAA Security_Information: Security_Classification_System: Not applicable Security_Classification: Unclassified Security_Handling_Description: Not applicable Data_Quality_Information: Logical_Consistency_Report: Unspecified Completeness_Report: Complete Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: The horizontal position accuracy for the camera sled position is 100 meters. There are three primary sources of this error. The ship's positioning is based on GPS SPS, often called standalone or non-differential GPS positioning. SPS has a measured accuracy of under 5 meters. The position of the GPS antenna is used; no attempt is made to translocate this position to that of the tow block from which the camera is deployed. The difference between the tow block and the antenna is about 14 meters. The camera sled position is based a layback calculation that use ship's course, the amount of cable out and the camera sled depth to develop an estimate of the camera sled position. The amount of cable deployed is manually entered by the operator during a given camera tow. Lineage: Process_Step: Process_Description: After a tow was completed the video tape data was reviewed by spot-checking the master and backup tape to verify that data were recorded. Navigation data were copied from the acquisition computer to the data archive. A metadata extractor (gloFilter.py, version 3/06) was run to summarize the navigation data and test for errors. If errors were detected they were corrected or flagged as appropriate and a new data file was made. This file's header was updated to document what type of processing occurred. A metadata file was recorded in the data archive in the same location as the navigation data. Processed navigation data were then read into ArcView 3.2 shapefiles using an ArcView Avenue script named "TOAD.Import.Playback", version 9/25/01, written by Ronald Hoeke. Process_Date: 20060320 Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Geographic: Latitude_Resolution: 0.0001 Longitude_Resolution: 0.0001 Geographic_Coordinate_Units: Decimal Degrees Geodetic_Model: Horizontal_Datum_Name: D_WGS_1984 Ellipsoid_Name: WGS_1984 Semi-major_Axis: 6378137.000000 Denominator_of_Flattening_Ratio: 298.257224 Vertical_Coordinate_System_Definition: Depth_System_Definition: Depth_Datum_Name: No correction Depth_Resolution: 0.1 Depth_Distance_Units: meters Depth_Encoding_Method: Attribute Values Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: Pacific Islands Benthic Habitat Mapping Center (PIBHMC), Coral Reef Ecosystem Division (CRED), Pacific Islands Fisheries Science Center (PIFSC), National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA) Contact_Person: John Rooney Contact_Address: Address_Type: mailing and physical address Address: NOAA IRC Address: NMFS/PIFSC/CRED Address: 1845 WASP Blvd., Building 176 City: Honolulu State_or_Province: HI Postal_Code: 96818 Contact_Voice_Telephone: 808 725-5360 Contact_Facsimile_Telephone: 808 725-5429 Contact_Electronic_Mail_Address: nmfs.pic.credinfo@noaa.gov Contact_Instructions: e-mail preferred Resource_Description: Offline Data Distribution_Liability: These data are not to be used for navigational purposes. NOAA makes no warranty regarding these data, expressed or implied, nor does the fact of distribution constitute such a warranty. NOAA cannot assume liability for any damages caused by any errors or omissions in these data, nor as a result of the failure of these data to function on a particular system. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: ASCII Format_Information_Content: Each comma-delimited record contains year, day of year, time, latitude, longitude, velocity north and east, water column depth, vehicle depth, layback, and wing angle. For this data set the fields for vehicle depth and wing angle do not contain useful data. List of navigation files: LAY04001.glo LAY04002.glo LAY04003.glo LAY04004a.glo Digital_Transfer_Option: Offline_Option: Offline_Media: CD-ROM Recording_Format: ISO 9660 Digital_Form: Digital_Transfer_Information: Format_Name: mini digital video and VHS Format_Information_Content: List of Video tapes: LAY04001-004, VHS, Master LAY04001-004a, Mini DV, Master LAY04001-004b, Mini DV, Master LAY04001-004a, Mini DV, Backup LAY04001-004b, Mini DV, Backup Digital_Transfer_Option: Offline_Option: Offline_Media: Video cassette tape Recording_Format: Mini DV Fees: None Metadata_Reference_Information: Metadata_Date: 20200329 Metadata_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: Pacific Islands Benthic Habitat Mapping Center (PIBHMC), Coral Reef Ecosystem Division (CRED), Pacific Islands Fisheries Science Center (PIFSC), National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA) Contact_Person: CRED Data Management Team Contact_Address: Address_Type: mailing and physical address Address: NOAA IRC Address: NMFS/PIFSC/CRED Address: 1845 WASP Blvd., Building 176 City: Honolulu State_or_Province: HI Postal_Code: 96818 Contact_Voice_Telephone: 808 725-5360 Contact_Facsimile_Telephone: 808 725-5429 Contact_Electronic_Mail_Address: nmfs.pic.credinfo@noaa.gov Contact_Instructions: e-mail preferred Metadata_Standard_Name: FGDC Content Standard for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998 CoRIS: CoRIS_ID: 20080502065011 CoRIS_Children: None CoRIS_Beginning_Date: 20040925 CoRIS_Ending_Date: 20040925 CoRIS_Metadata_Link: https://www.coris.noaa.gov/metadata/records/html/cred_toad_laysan_hi0401_2004.html CoRIS_Tracking_ID: 1477