Short Citation:
Pacific Islands Fisheries Science Center, 2021: Seafloor substrate (hard and soft bottom) maps derived from satellite imagery for the islands and atolls of the Pacific Remote Island Areas, https://www.fisheries.noaa.gov/inport/item/54217.

Item Identification

Title: Seafloor substrate (hard and soft bottom) maps derived from satellite imagery for the islands and atolls of the Pacific Remote Island Areas
Short Name: Hard Soft Substrate: Satellite Image
Status: Completed
Creation Date: 2018
Publication Date: 2018
Abstract:

Seafloor substrate (i.e., hard vs. soft bottom) from 0 to up to 30 m depths around islands/atolls in Pacific Remote Island Areas produced by the NOAA Ecosystem Sciences Division (ESD). The islands/atolls include Howland, Baker, Jarvis, Kingman Reef, Palmyra Atoll, Johnston Atoll, Wake Atoll. This is a preliminary product derived from an unsupervised classification of depth-invariant indices prepared from high resolution satellite images. Unsupervised classification segmented the indices into multiple classes, and the binary substrate map was produced by mapping interpreter's informed judgments in attributing the predicted classes. Where required, area-specific class attribution and minor manual editing were undertaken to remove inaccurate predictions.

Purpose:

Hard and soft seafloor maps were initially requested by the NOAA Pacific Islands Regional Office (PIRO) Protected Resources Division to assist with management of 15 coral species that occur in the Indo-Pacific and are listed threatened under the Endangered Species Act. Some of these coral species are known to be found in American Samoa, the Mariana Archipelago, and the Pacific Remote Island Areas. As part of the effort, the shallow water hard and soft seafloor maps for the Pacific Remote Islands were newly generated where no such information existed in the region except for Palmyra Atoll. The effort is funded by the NOAA Coral Reef Conservation Program.

In addition, along with the deeper water hard and soft seafloor maps, these maps are included in the Pacific Remote Islands Marine National Monument monitoring report, which is being developed in 2018 for NOAA Pacific Islands Regional Office (PIRO) Marine National Monument Program. The effort is funded by the NOAA Coral Reef Conservation Program and NOAA PIRO.

Keywords

Theme Keywords

Thesaurus Keyword
CoRIS Discovery Thesaurus Geographic Information > Habitats
CoRIS Theme Thesaurus EARTH SCIENCE > Biosphere > Aquatic Habitat > Benthic Habitat
CoRIS Theme Thesaurus EARTH SCIENCE > Biosphere > Aquatic Habitat > Reef Habitat
CoRIS Theme Thesaurus EARTH SCIENCE > Biosphere > Zoology > Corals > Reef Monitoring and Assessment > Mapping > geomorphology Mapping
CoRIS Theme Thesaurus EARTH SCIENCE > Biosphere > Zoology > Corals > Reef Monitoring and Assessment > Mapping > Habitat Mapping
CoRIS Theme Thesaurus EARTH SCIENCE > Oceans > Bathymetry/Seafloor Topography > Hard Seafloor Substrate
CoRIS Theme Thesaurus EARTH SCIENCE > Oceans > Bathymetry/Seafloor Topography > Soft Seafloor Substrate
CoRIS Theme Thesaurus EARTH SCIENCE > Oceans > Coastal Processes > Coral Reefs
CoRIS Theme Thesaurus EARTH SCIENCE > Oceans > Coastal Processes > Coral Reefs > Coral Reef Ecology > Habitats
CRCP Project Mapping and EcoSpatial Information Products to Support Coral Reef Ecosystem Management in the Pacific Islands Region
ISO 19115 Topic Category 002
ISO 19115 Topic Category 014
ISO 19115 Topic Category biota
ISO 19115 Topic Category oceans
NODC DATA TYPES THESAURUS SUBSTRATE DESCRIPTION
NODC OBSERVATION TYPES THESAURUS benthic
NODC OBSERVATION TYPES THESAURUS GIS product
NODC PROJECT NAMES THESAURUS Coral Reef Conservation Program
NODC SUBMITTING INSTITUTION NAMES THESAURUS US DOC; NOAA; NMFS; Pacific Islands Fisheries Science Center; Ecosystem Sciences Division
None Coral Reef Ecosystem Division
None Coral Reef Ecosystem Program
None CRED
None CREP
None Ecosystem Sciences Division
None ESD
None Pacific Islands Fisheries Science Center
None PIFSC

Spatial Keywords

Thesaurus Keyword
CoRIS Place Thesaurus COUNTRY/TERRITORY > United States of America > USA Minor Outlying Islands > Baker Island (00N176W0001)
CoRIS Place Thesaurus COUNTRY/TERRITORY > United States of America > USA Minor Outlying Islands > Howland Island (00S176W0001)
CoRIS Place Thesaurus COUNTRY/TERRITORY > United States of America > USA Minor Outlying Islands > Jarvis Island (00S160W0001)
CoRIS Place Thesaurus COUNTRY/TERRITORY > United States of America > USA Minor Outlying Islands > Johnston Atoll (16N169W0001)
CoRIS Place Thesaurus COUNTRY/TERRITORY > United States of America > USA Minor Outlying Islands > Kingman Reef (06N162W0001)
CoRIS Place Thesaurus COUNTRY/TERRITORY > United States of America > USA Minor Outlying Islands > Palmyra Atoll (05N162W0001)
CoRIS Place Thesaurus COUNTRY/TERRITORY > United States of America > USA Minor Outlying Islands > Wake Atoll (19N167E0001)
CoRIS Place Thesaurus OCEAN BASIN > Pacific Ocean > Central Pacific Ocean > Baker Island > Baker Island (00N176W0001)
CoRIS Place Thesaurus OCEAN BASIN > Pacific Ocean > Central Pacific Ocean > Howland Island > Howland Island (00S176W0001)
CoRIS Place Thesaurus OCEAN BASIN > Pacific Ocean > Central Pacific Ocean > Johnston Atoll > Johnston Atoll (16N169W0001)
CoRIS Place Thesaurus OCEAN BASIN > Pacific Ocean > Central Pacific Ocean > Line Islands > Jarvis Island (00S160W0001)
CoRIS Place Thesaurus OCEAN BASIN > Pacific Ocean > Central Pacific Ocean > Line Islands > Kingman Reef (06N162W0001)
CoRIS Place Thesaurus OCEAN BASIN > Pacific Ocean > Central Pacific Ocean > Line Islands > Palmyra Atoll (05N162W0001)
CoRIS Place Thesaurus OCEAN BASIN > Pacific Ocean > Central Pacific Ocean > Wake Atoll > Wake Atoll (19N167E0001)
NODC SEA AREA NAMES THESAURUS Equatorial Pacific Ocean
NODC SEA AREA NAMES THESAURUS Pacific Remote Islands Marine National Monument
None Pacific Remote Island Areas
None PRIA

Stratum Keywords

Thesaurus Keyword
Global Change Master Directory SEA FLOOR

Physical Location

Organization: Pacific Islands Fisheries Science Center
City: Honolulu
State/Province: HI
Country: USA

Data Set Information

Data Set Scope Code: Data Set
Data Set Type: GIS dataset of raster files
Maintenance Frequency: None Planned
Data Presentation Form: Map (digital)
Entity Attribute Overview:

Hard and soft substrate classes. Value 1 = hard, value 2 = soft

Entity Attribute Detail URL: https://www.fisheries.noaa.gov/inport/item/54219
Distribution Liability:

While every effort has been made to ensure that these data are accurate and reliable within the limits of the current state of the art, NOAA cannot assume liability for any damages caused by errors or omissions in the data, nor as a result of the failure of the data to function on a particular system. NOAA makes no warranty, expressed or implied, nor does the fact of distribution constitute such a warranty.

Data Set Credit: PIFSC Ecosystem Sciences Division and funded by the NOAA Coral Reef Conservation Program

Support Roles

Data Set Credit

CC ID: 788481
Date Effective From: 2018
Date Effective To:
Contact (Organization): NOAA Coral Reef Conservation Program (CRCP) (CRCP)
Address: 1305 East West Highway 10th Floor
Silver Spring, MD 20910-3281
Phone: (301) 713-3155
URL: http://coralreef.noaa.gov

Data Steward

CC ID: 788478
Date Effective From: 2018
Date Effective To:
Contact (Person): Acoba, Tomoko S
Address: 1845 Wasp Blvd.
Honolulu, HI 96818
USA
Email Address: tomoko.acoba@noaa.gov
Phone: (808)725-5448
Business Hours: 8:00 am - 4:00 pm HST
Contact Instructions:

Email preferred

Distributor

CC ID: 788477
Date Effective From: 2018
Date Effective To:
Contact (Organization): Pacific Islands Fisheries Science Center (PIFSC)
Address: 1845 Wasp Blvd.
Honolulu, HI 96818
USA
Phone: 808-725-5300
URL: http://www.pifsc.noaa.gov
Business Hours: 8:00 a.m. - 4:30 p.m.
Contact Instructions:

via the Pacific Islands Benthic Habitat Mapping Center (PIBHMC) website

Metadata Contact

CC ID: 788476
Date Effective From: 2018
Date Effective To:
Contact (Person): DesRochers, Annette M
Address: 1845 Wasp Blvd.
Honolulu, HI 96818
USA
Email Address: annette.desrochers@noaa.gov
Phone: (808)725-5461
Business Hours: 8 am - 5 pm
Contact Instructions:

Email preferred

Originator

CC ID: 788479
Date Effective From: 2018
Date Effective To:
Contact (Organization): Pacific Islands Fisheries Science Center (PIFSC)
Address: 1845 Wasp Blvd.
Honolulu, HI 96818
USA
Phone: 808-725-5300
URL: http://www.pifsc.noaa.gov
Business Hours: 8:00 a.m. - 4:30 p.m.

Point of Contact

CC ID: 788480
Date Effective From: 2018
Date Effective To:
Contact (Person): DesRochers, Annette M
Address: 1845 Wasp Blvd.
Honolulu, HI 96818
USA
Email Address: annette.desrochers@noaa.gov
Phone: (808)725-5461
Business Hours: 8 am - 5 pm
Contact Instructions:

Email preferred

Extents

Currentness Reference: Ground Condition

Extent Group 1

Extent Description:

Select locations in the Pacific Remote Islands Marine National Monument (PRIMNM), also known as the Pacific Remote Island Areas (PRIA), including Wake, Baker, and Howland islands, Johnston and Palymra atolls, and Kingman reef.

Extent Group 1 / Geographic Area 1

CC ID: 788636
W° Bound: 166.583
E° Bound: 166.667
N° Bound: 19.333
S° Bound: 19.2583
Description

The geographic extent of Wake Atoll

Extent Group 1 / Geographic Area 2

CC ID: 788474
W° Bound: -176.7
E° Bound: -159.8
N° Bound: 16.75
S° Bound: -0.7
Description

Johnston Atoll, Baker Island, Howland Island, Jarvis Island, Kingman Reef, and Palmyra Atoll in Pacific Remote Island Areas. The geographic extent of Johnston Atoll (to the North), Howland and Baker (to the West), and Jarvis Island (to the South and East).

Extent Group 1 / Time Frame 1

CC ID: 788471
Time Frame Type: Range
Start: 2011
End: 2017
Description:

Time frame of WorldView 2 or 3 imagery for Howland, Baker, Jarvis, Johnston Atoll, Kingman Reef, Palmyra Atoll, Wake Atoll in Pacific Remote Islands

Access Information

Security Class: Unclassified
Security Classification System:

Not applicable

Security Handling Description:

Not applicable

Data Access Policy:

NOAA Coral Reef Ecosystem Program (CREP) Data Sharing Recommendations, version 9.0 updated August 12, 2015:

CREP welcomes the opportunity to collaborate on research issues contributing to the scientific basis for better management of marine ecosystems. CREP has a very diverse set of field activities that generates large volumes of data using an array of data collection protocols.

The following recommendations are for your consideration as you use this data:

1) Data analyses should take all field exigencies into account. The most effective way to do this would be active collaboration with CREP principal investigators.

2) In all presentations, product releases, or publications using data generated by CREP, proper acknowledgement of both CREP and the individuals responsible for data collection is expected. Citing the DOI (if available) is preferred, a non-DOI example is listed below.

3) If you collect or generate data for the same study areas, CREP requests that you share relevant information on complimentary data collections.

4) Those receiving data are strongly urged to inform the CREP Data Management Team of any errors and discrepancies that are discovered during the course of using these data. They are further urged to bring to the attention of the Team all problems and difficulties encountered in using these data. This information is necessary in order to improve the collections and to facilitate more efficient and economical data processing and retrieval. The users are asked to supply copies of any missing data that may be located, and to provide information as to significant subsets and special aggregations of data that are developed in using the material provided.

Example citation:

"This publication makes use of data products provided by the Coral Reef Ecosystem Program (CREP), Pacific Islands Fisheries Science Center (PIFSC), National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA), with funding support from the NOAA Coral Reef Conservation Program (CRCP). The analysis and interpretations presented here are solely that of the current authors.”

Data Access Procedure:

Data can be accessed online via the Pacific Islands Benthic Habitat Mapping Center website via the FTP link provided in the distribution section.

Data Access Constraints:

None

Data Use Constraints:

These data are not to be used for navigation purposes.

Please cite NOAA Pacific Islands Fisheries Science Center (PIFSC), Ecosystem Sciences Division (ESD) when using the data.

Pacific Islands Fisheries Science Center, Ecosystem Sciences Division (2018). Seafloor substrate (hard and soft bottom) maps at select islands/atolls in American Samoa, Mariana Archipelago, and the Pacific Remote Island Areas. https://www.fisheries.noaa.gov/inport/item/34310.

Metadata Access Constraints:

None

Metadata Use Constraints:

None

Distribution Information

Distribution 1

CC ID: 788687
Download URL: ftp://ftp.soest.hawaii.edu/pibhmc/website/data/pria/benthichabitatlayers/bak_wv_2m_hardsoft.zip
Distributor: Pacific Islands Fisheries Science Center (PIFSC) (2018 - Present)
File Name: bak_wv_2m_hardsoft.zip
Description:

Newly developed Hard and Soft Bottom Seafloor Substrate Map of Baker Island, Pacific Remote Islands. The zip file contains the product in GeoTIFF format with the PDF map showing the extent of the product. The readme text file describing the detailed processing steps is also included. Source WorldView 2 satellite image: 2012 and WorldView 3 satellite images: 2016. The data are provided by the Pacific Islands Fisheries Science Center and hosted by UH on SOEST servers.

File Date/Time: 2018-11-15 00:00:00
File Type: GeoTIFF
Compression: Zip

Distribution 2

CC ID: 788494
Download URL: ftp://ftp.soest.hawaii.edu/pibhmc/website/data/pria/benthichabitatlayers/how_wv_2m_hardsoft.zip
Distributor: Pacific Islands Fisheries Science Center (PIFSC) (2018 - Present)
File Name: how_wv_2m_hardsoft.zip
Description:

Newly developed Hard and Soft Bottom Seafloor Substrate Map of Howland Island, Pacific Remote Islands. The zip file contains the product in GeoTIFF format with the PDF map showing the extent of the product. The readme text file describing the detailed processing steps is also included. Source WorldView 2 satellite images: 2011 and 2016. The data are provided by the Pacific Islands Fisheries Science Center and hosted by UH on SOEST servers.

File Date/Time: 2018-11-15 00:00:00
File Type: GeoTIFF
Compression: Zip

Distribution 3

CC ID: 788495
Download URL: ftp://ftp.soest.hawaii.edu/pibhmc/website/data/pria/benthichabitatlayers/jar_wv_2m_hardsoft.zip
Distributor: Pacific Islands Fisheries Science Center (PIFSC) (2018 - Present)
File Name: jar_wv_2m_hardsoft.zip
Description:

Newly developed Hard and Soft Bottom Seafloor Substrate Map of Jarvis Island, Pacific Remote Islands. The zip file contains the product in GeoTIFF format with the PDF map showing the extent of the product. The readme text file describing the detailed processing steps is also included. Source WorldView 2 satellite image: 2016. The data are provided by the Pacific Islands Fisheries Science Center and hosted by UH on SOEST servers.

File Date/Time: 2018-11-15 00:00:00
File Type: GeoTIFF
Compression: Zip

Distribution 4

CC ID: 788497
Download URL: ftp://ftp.soest.hawaii.edu/pibhmc/website/data/pria/benthichabitatlayers/joh_wv_2m_hardsoft.zip
Distributor: Pacific Islands Fisheries Science Center (PIFSC) (2018 - Present)
File Name: joh_wv_2m_hardsoft.zip
Description:

Newly developed Hard and Soft Bottom Seafloor Substrate Map of Johnston Atoll, Pacific Remote Islands. The zip file contains the product in GeoTIFF format with the PDF map showing the extent of the product. The readme text file describing the detailed processing steps is also included. Source WorldView 2 satellite image: 2014. The data are provided by the Pacific Islands Fisheries Science Center and hosted by UH on SOEST servers.

File Date/Time: 2018-11-15 00:00:00
File Type: GeoTIFF
Compression: Zip

Distribution 5

CC ID: 788496
Download URL: ftp://ftp.soest.hawaii.edu/pibhmc/website/data/pria/benthichabitatlayers/kin_wv_2m_hardsoft.zip
Distributor: Pacific Islands Fisheries Science Center (PIFSC) (2018 - Present)
File Name: kin_wv_2m_hardsoft.zip
Description:

Newly developed Hard and Soft Bottom Seafloor Substrate Map of Kingman Reef, Pacific Remote Islands. The zip file contains the product in GeoTIFF format with the PDF map showing the extent of the product. The readme text file describing the detailed processing steps is also included. Source WorldView 2 satellite image: 2015. The data are provided by the Pacific Islands Fisheries Science Center and hosted by UH on SOEST servers.

File Date/Time: 2018-11-19 00:00:00
File Type: GeoTIFF
Compression: Zip

Distribution 6

CC ID: 788498
Download URL: ftp://ftp.soest.hawaii.edu/pibhmc/website/data/pria/benthichabitatlayers/pal_wv_2m_hardsoft.zip
Distributor: Pacific Islands Fisheries Science Center (PIFSC) (2018 - Present)
File Name: pal_wv_2m_hardsoft.zip
Description:

Newly developed Hard and Soft Bottom Seafloor Substrate Map of Palmyra Atoll, Pacific Remote Islands. The zip file contains the product in GeoTIFF format with the PDF map showing the extent of the product. The readme text file describing the detailed processing steps is also included. Source WorldView 2 satellite images: 2014. The data are provided by the Pacific Islands Fisheries Science Center and hosted by UH on SOEST servers.

File Date/Time: 2018-11-15 00:00:00
File Type: GeoTIFF
Compression: Zip

Distribution 7

CC ID: 788703
Download URL: ftp://ftp.soest.hawaii.edu/pibhmc/website/data/pria/benthichabitatlayers/wak_wv_2m_hardsoft.zip
Distributor: Pacific Islands Fisheries Science Center (PIFSC) (2018 - Present)
File Name: wak_wv_2m_hardsoft.zip
Description:

Newly developed Hard and Soft Bottom Seafloor Substrate Map of Wake Atoll, Pacific Remote Islands. The zip file contains the product in GeoTIFF format with the PDF map showing the extent of the product. The readme text file describing the detailed processing steps is also included. Source WorldView satellite images: 2014 (WorldView 3) and 2017 (WorldView 2). The data are provided by the Pacific Islands Fisheries Science Center and hosted by UH on SOEST servers.

File Date/Time: 2018-11-19 00:00:00
File Type: GeoTIFF
Compression: Zip

URLs

URL 1

CC ID: 788499
URL: http://www.soest.hawaii.edu/pibhmc/amsamoa_images/TUT_unspv_hardvsoft_5m_445.jpg
Name: Hard and Soft Substrate map of Tutuila
URL Type:
Browse Graphic
File Resource Format: JPG
Description:

An example hard- and soft-bottom substrate map of Tutuila (prepared using a different methodology compared with the substrate maps prepared for the project described here).

URL 2

CC ID: 788500
URL: https://www.soest.hawaii.edu/pibhmc/cms/
Name: Pacific Islands Benthic Habitat Mapping Center (PIBHMC) website
URL Type:
Online Resource
Description:

NOAA ESD source data are accessible through this website.

Technical Environment

Description:

GeoTIFF created using ArcGIS 10.5.1 in a Microsoft Windows environment.

Data Quality

Representativeness:

The predictive substrate maps were produced from recently acquired WorldView satellite images.

Accuracy:

The hard soft substrate classification results were compared against the ESD's biological survey locations (both fish and coral), with 95% to 99.5 % agreement.

Analytical Accuracy:

As of yet, these data have not been compared with external references or other published data.

Completeness Report:

These maps may be subject to updates as new data and information become available.

Conceptual Consistency:

Palmyra Atoll was the first place in Pacific Remote Islands to adopt the method of deriving the hard/soft substrate map developed for West Hawaii and the method revolved and streamlined as moved to the other places in the Pacific Remote Islands. Specifically, the polygons smaller than 20m2 (10x cell size) was removed instead of 10m2 (5x cell size); the inaccurate classes in the shallow internal lagoon were replaced with the manually digitized polygons, instead of altering the class attributes to correct the classes; and the mask to remove the waves, clouds and lands were applied as the final step, instead of applying them before clustering.

More detailed processing steps taken for each place are described in its readme file.

Quality Control Procedures Employed:

The method was developed initially for an area in West Hawaii where multiple sources of accurate, reliable data were available. Applying the method to islands in the Pacific Remote Island Areas, the process and resulting classifications were quality controlled by a group of team members before the products were finalized.

Data Management

Have Resources for Management of these Data Been Identified?: Yes
Approximate Percentage of Budget for these Data Devoted to Data Management: Unknown
Do these Data Comply with the Data Access Directive?: Yes
Is Access to the Data Limited Based on an Approved Waiver?: No
Approximate Delay Between Data Collection and Dissemination: Unknown
Actual or Planned Long-Term Data Archive Location: Other
If World Data Center or Other, Specify: Pacific Islands Benthic Habitat Mapping Center
Approximate Delay Between Data Collection and Archiving: Unknown
How Will the Data Be Protected from Accidental or Malicious Modification or Deletion Prior to Receipt by the Archive?:

University of Hawaii School of Ocean and Earth Science and Technology, NOAA IRC and NOAA Fisheries ITS resources and assets.

Lineage

Lineage Statement:

Satellite images were processed for the Pacific Remote Island Areas using the method described in Mumby and Edwards (2000) and then, unsupervised classification was applied to derive Hard and Soft substrates. ENVI 5.3 (Harris Geospatial Solutions, Inc.) and ArcGIS 10.5.1 (Esri, Inc.) The lineage describes the general processing steps. The detailed steps and coefficients for each place are described in the readme file in the zip file.

Sources

Absolute Radiometric Calibration: 2016v0

CC ID: 788706
Publish Date: 2017-06-06
Citation URL: https://dg-cms-uploads-production.s3.amazonaws.com/uploads/document/file/209/ABSRADCAL_FLEET_2016v0_Rel20170606.pdf
Citation URL Name: PDF documentation containing absolute calibration factors for the WorldView 2 and 3 satellite images

Dove, D., Acoba, T., DesRochers, A. Seafloor Substrate Characterization from Shallow Reefs to the Abyss: Spatially-continuous seafloor mapping using multispectral satellite imagery, and multibeam bathymetry and backscatter data within the Pacific Remote Islands Marine National Monument and the Main Hawaiian Islands. 2018. PIFSC Internal Report IR-18-08. Issued 18 October 2018.

CC ID: 788711
Publish Date: 2018-10-31
Citation URL: https://origin-apps-pifsc.fisheries.noaa.gov/library/pubs/IR-18-018.pdf
Citation URL Name: NOAA Fisheries Pacific Islands Fisheries Science Center
Source Contribution:

Describes methods development and decision tree.

Mumby, P. J., Edwards, A. J. Water column correction techniques. In Remote Sensing Handbook for Tropical Coastal Management. Green, E. P., Mumby, P. J., Edwards, A. J., Clark, C.D., Eds. UNESCO: Parisk, France, 2000. Pp. 121-128.

CC ID: 788536
Extent Type: Discrete
Extent Start Date/Time: 2000
Citation URL: http://unesdoc.unesco.org/images/0011/001197/119752E.pdf
Citation URL Name: UNESDOC
Citation URL Description:

the UNESCO Digital Library website

Palmyra Atoll Quickbird II Seafloor Mosaic (1.8m)

CC ID: 788535
Extent Type: Range
Extent Start Date/Time: 2006
Extent End Date/Time: 2009
Citation URL: https://www.coris.noaa.gov/metadata/records/html/palmyra_seafloor_mosaic.html
Citation URL Name: CoRIS: Coral Reef Information System
Citation URL Description:

The Coral Reef Conservation Program's (CRCP) information portal that provides access to NOAA coral reef information and data products with emphasis on the U.S. states, territories and remote island areas.

Process Steps

Process Step 1

CC ID: 788704
Description:

Worldview 2 or Worldview 3 satellite images are acquired through the NEXTVIEW Imagery License Agreement between DigitalGlobe, Inc. and National Geospatial Intelligence Agency (NGA). Under the agreement, the images are available for the use by the U.S. Government. Standard product level (2A) of multispectral and pancrhomatic images were acquired to produce hard soft maps. The images meeting the following criteria are carefully selected : cloud and shadow free, relatively small surf breaks, little sunglint on the water surface and little turbidity in the water.

Process Step 2

CC ID: 788705
Description:

The satellite images were preprocessed before generating the depth invariant indices using the tools available in ENVI 5.3. The images were first orthorectified using the RPC Orthorectification Workflow tool. The images are then radiometrically corrected and converted into the radiance using the Radiometric Calibration tool and Apply Gain and Offset tool. Radiometric calibration factors for each image are provided by DigitalGlobe in the associated metadata. The absolute calibration factors are available in the online documentation made available by DigitalGlobe.

Source: Absolute Radiometric Calibration: 2016v0

Process Step 3

CC ID: 788707
Description:

The atmospheric correction steps described in Mumby and Edwards (2000) were applied to the radiance images remove some of the atmospheric influences on the images. The calculation is sequenced in ENVI 5.3/IDL 8.5.

Source: Mumby, P. J., Edwards, A. J. Water column correction techniques. In Remote Sensing Handbook for Tropical Coastal Management. Green, E. P., Mumby, P. J., Edwards, A. J., Clark, C.D., Eds. UNESCO: Parisk, France, 2000. Pp. 121-128.

Process Step 4

CC ID: 788709
Description:

Depth Invariant Index in Mumby and Edwards (2000) were derived for 10 band pairs of each image. The band pairs are: Coastal - Blue, Coastal - Green, Coastal - Yellow, Coastal - Red, Blue - Green, Blue - Yellow, Blue - Red, Green - Yellow, Green - Red, Yellow - Red. Following equation was applied to each band pair using using the Band Math tool in ENVI 5.3 to derive the Depth Invariant Index.

Depth Invariant Index of band pair i and j = Li -[(ki/kj)*Lj]

where

Li = Radiance or Reflectance values of band i

Lj = Radiance or Reflectance values of band j

ki/kj = Ratio of attenuation coefficients of band i and j

Ratio of attenuation coefficients were derived in Excel spreadsheet using the variance and covariance of the radiance values extracted over shallow and deep sandy bottoms of each image.

The results were exported as GeoTiff for the further analysis in ArcGIS.

Source: Mumby, P. J., Edwards, A. J. Water column correction techniques. In Remote Sensing Handbook for Tropical Coastal Management. Green, E. P., Mumby, P. J., Edwards, A. J., Clark, C.D., Eds. UNESCO: Parisk, France, 2000. Pp. 121-128.

Process Step 5

CC ID: 788710
Description:

The ISO Cluster Unsupervised Classification tool in ArcGIS 10.5.1 was employed to segment the depth invariant indices into multiple classes. Number of iterations were set to be 5, and minimum class size were set to be 3. Up to 15 classes were generated for each band pair of the depth invariant index.

Source: Dove, D., Acoba, T., DesRochers, A. Seafloor Substrate Characterization from Shallow Reefs to the Abyss: Spatially-continuous seafloor mapping using multispectral satellite imagery, and multibeam bathymetry and backscatter data within the Pacific Remote Islands Marine National Monument and the Main Hawaiian Islands. 2018. PIFSC Internal Report IR-18-08. Issued 18 October 2018.

Process Step 6

CC ID: 790390
Description:

Each band pair classification was visually examined by inspecting the cluster results against the substrate boundaries that can be identified in the original satellite images. The best band pair classification result detecting the substrate boundaries was chosen, and interpreters made an informed judgement in attributing the predicted classes into hard and soft. Where required, area-specific class attribution and minor manual editing were undertaken to remove inaccurate predictions in ArcGIS 10.5.1. Output file type is GeoTIFF.

Source: Dove, D., Acoba, T., DesRochers, A. Seafloor Substrate Characterization from Shallow Reefs to the Abyss: Spatially-continuous seafloor mapping using multispectral satellite imagery, and multibeam bathymetry and backscatter data within the Pacific Remote Islands Marine National Monument and the Main Hawaiian Islands. 2018. PIFSC Internal Report IR-18-08. Issued 18 October 2018.

Process Step 7

CC ID: 790391
Description:

Where multiple images are available, the same steps are applied to the second image, and the gaps of the classification result in the first image will be filled with the second image.

Acquisition Information

Instruments

Instrument Unavailable Reason: Not Applicable

Platforms

Platform Unavailable Reason: Not Applicable

Child Items

Rubric scores updated every 15m

Rubric Score Type Title
Entity (ENT) Substrate Classes

Related Items

Item Type Relationship Type Title
Data Set (DS) Larger Work Citation Seafloor substrate (hard and soft bottom) maps derived from multibeam echo-sounder bathymetry and backscatter for the islands and atolls of the Pacific Remote Island Areas

Deep water analysis, part of IR-18-018.

Catalog Details

Catalog Item ID: 54217
Metadata Record Created By: Tomoko S Acoba
Metadata Record Created: 2018-10-17 15:09+0000
Metadata Record Last Modified By: SysAdmin InPortAdmin
Metadata Record Last Modified: 2020-08-03 16:13+0000
Metadata Record Published: 2019-05-30
Owner Org: PIFSC
Metadata Publication Status: Published Externally
Do Not Publish?: N
Metadata Next Review Date: 2020-05-30