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Identification

Field Value

Title

NSW Marine Estate Towed Video Imagery

Alternative title(s)

NSW Marine still imagery of the seabed for the NSW continental shelf

Abstract

Raw downward facing still imagery of the seabed over the NSW continental shelf acquired using NSW government's (Department of Climate Change Energy Environment and Water) towed video system aboard RV Bombora. Acquisition is ongoing (>2015) predominantly funded by the department under Coastal Reform Climate Change Fund project 'State-wide Science' and/or by various collaborative agencies (DPI; Parks Australia; FRDC) and educational institutions (UoW: UTas). Imagery is captured over areas to 1) ground-truth seabed typologies and validate habitat boundaries derived from multi-beam echosounder (MBES) surveys (www.aodn.org.au or www.ausseabed.gov.au) and/or 2) habitat assessments and monitoring to capture broad distribution of seabed benthic communities. For biodiversity-type assessments, imagery is captured, and transects/sites are selected in a sampling design in accordance with the Australian Field Manuals for Marine Sampling. Imagery captured is generally of benthic habitats in 10-120m of water depth over the NSW inner shelf. Georeferenced (XYZ) and time-stamped (UTC) still imagery is accessible via SEED, the online annotation platform Squidle+ and SeaMap Australia.

Resource locator

Data Quality Statement

Name: Data Quality Statement

Protocol: WWW:DOWNLOAD-1.0-http--download

Description:

Data quality statement for NSW Marine Estate Towed Video Imagery

Function: download

Unique resource identifier

Code

406af3af-e466-434c-84fa-63d6c02af35e

Presentation form

Image digital

Edition

1

Dataset language

English

Metadata standard

Name

ISO 19115

Edition

2016

Dataset URI

https://www.planningportal.nsw.gov.au/opendata/dataset/406af3af-e466-434c-84fa-63d6c02af35e

Purpose

baseline for monitoring

Status

Completed

Spatial representation type

video

Spatial reference system

Code identifying the spatial reference system

4283

Spatial resolution

1 m

Additional information source

Data were collected on 5-6 separate dates during the time period to acquire imagery once from each for the randomly selected locations identified at the start of the survey.

Classification of spatial data and services

Field Value

Topic category

imageryBaseMapsEarthCover

Keywords

Field Value

Keyword set

keyword value

MARINE-Biology

MARINE-Coasts

MARINE-Reefs

PHOTOGRAPHY-AND-IMAGERY-Remote-Sensing

Originating controlled vocabulary

Title

ANZLIC Search Words

Reference date

2008-05-16

Geographic location

NSW Place Name

Port Stephens Great Lakes

Vertical extent information

Minimum value

-100

Maximum value

2228

Coordinate reference system

Authority code

urn:ogc:def:cs:EPSG::

Code identifying the coordinate reference system

5711

Temporal extent

Begin position

2019-10-20

End position

N/A

Dataset reference date

Resource maintenance

Maintenance and update frequency

Unknown

Contact info

Contact position

Data Broker

Organisation name

NSW Department of Climate Change, Energy, the Environment and Water

Full postal address

NSW

Australia

data.broker@environment.nsw.gov.au

Telephone number

131555

Email address

data.broker@environment.nsw.gov.au

Web address

https://www.nsw.gov.au/departments-and-agencies/dcceew

Responsible party role

pointOfContact

Quality and validity

Field Value

Lineage

Video surveying was undertaken following the recommendations detailed in 'Field Manuals for Marine Sampling to Monitor Australian Waters' ( https://www.nespmarine.edu.au/field-manuals-marine-sampling-monitor-australian-waters). Details of the NSW DPIE towed video system and equipment are provided in 'SeaBed NSW: Standard Operating Procedures of multibeam surveying' (https://www.environment.nsw.gov.au/-/media/OEH/Corporate-Site/Documents/Research/Our-science-and-research/seabed-nsw-standard-operating-procedures-multibeam-surveying-190101.pdf). XYZ positional accuracy of the still imagery is better than XY (3 degrees of slant range [eg. 2.6m radius @ 100m]; 2x ship’s speed for XY (horizontal) and/or >2x cable speed for Z (vertical). Filtered coordinates were then used to estimate ‘fish’ GPS location using the neighbouring average ( 3s time-step). Where a coordinate estimate was performed using one of these methods, the image’s metadata “Flag” column was populated with a “1” or “3” respectively. Interpolated positions were then validated by comparison of image content against bathymetric features at corresponding coordinates, primarily at transitions between high-relief reef and low-relief sediment. Image (JPG) and image metadata records (generated in csv format) were uploaded for access and annotation in Squidle+.

Constraints related to access and use

Field Value

Constraint set

Use constraints

This data is provided under a Creative Commons Attribution 4.0 licence http://creativecommons.org/licenses/by/4.0. Attribute 'NSW Department of Climate Change, Energy, the Environment and Water' in publications using this data.

Limitations on public access

Data Quality

Field Value

Scope

dataset

DQ Conceptual Consistency

Effective date

2020-05-18

Explanation

As the imagery is acquired using a moving platform some images may capture the same section of seabed. Survey speed of ~1kt (0.51m/s); image capture rate 1 image every 2 seconds; and approximate area of seabed captured in each image. nb: tow-fish roll, pitch and heave values are recorded by the video camera and saved within the video data file.

DQ Absolute External Positional Accuracy

Effective date

2020-05-18

Explanation

Squidle+ ingestion of data requires a position and an altimetry value or height of the 'tow fish' above the seabed. At the time of acquisition, the the towed video system did not have an altimeter and thus the height of the tow fish was estimated as Tow-Fish Altitude = [Water Depth at Tow-Fish (from MBES survey)] - [Tow-Fish Pressure Sensor Depth] + [P-Sensor to SLR camera (offset =0.52)] nb. P-sensor value is not corrected for tide whereas MBES data is static to AHD. XY position of fish is determined by relative position of USBL transponder (fish) to transceiver (vessel). GPS position is G2 quality (~0.4-0.5 in real-time) and is relative to the vessels Centre of Mass (reference frame 0:0:0) with a 12.4m forward offset (X = -1.5) from transceiver to COM entered in the USBL software (Y = 0). USBL heading offset is checked following each installation (nominally 23 degrees from centreline) and USBL (Tracklink, USA) precision is 3 degrees of slant range value. Original image time-stamping is synched with computer UTC (<1s) but naming convention uses USBL/Video text feed based on POS MV output.

Responsible organisations

Field Value

Responsible party

Contact position

Data Broker

Organisation name

NSW Department of Climate Change, Energy, the Environment and Water

Full postal address

NSW

Australia

data.broker@environment.nsw.gov.au

Telephone number

131555

Email address

data.broker@environment.nsw.gov.au

Web address

https://www.nsw.gov.au/departments-and-agencies/dcceew

Responsible party role

pointOfContact

Metadata on metadata

Field Value

Metadata point of contact

Contact position

Data Broker

Organisation name

NSW Department of Climate Change, Energy, the Environment and Water

Full postal address

NSW

Australia

data.broker@environment.nsw.gov.au

Telephone number

131555

Email address

data.broker@environment.nsw.gov.au

Web address

https://www.nsw.gov.au/departments-and-agencies/dcceew

Responsible party role

pointOfContact

Metadata date

2024-02-26T13:43:57.256516

Metadata language