Identification

Title

2015 - 2015 Centre for Environment, Fisheries & Aquaculture Science (Cefas) Fladen experimental fishing impact recovery data - Acoustic data

Abstract

Output imagery of multibeam echosounder backscatter (tiffs) from within six experimental boxes (three treatments and three control) during a fishing impact recovery survey within the Fladen Grounds. Data were collected at three time points (before impact (time 0), immediately after impact (time 1) and 8 months after impact (time 2) during two research surveys on the RV Cefas Endeavour in April 2015 and November 2015.

Resource type

dataset

Resource locator

http://data.cefas.co.uk/#/View/19706/

function: order

Unique resource identifier

code

CEFAS969e1824-ccb8-4ae2-ae4c-32a1d3d4a8a9

codeSpace

http://www.cefas.co.uk/

Dataset language

eng

Spatial reference system

authority code

OGP

code identifying the spatial reference system

urn:ogc:def:crs:EPSG::4326

Classification of spatial data and services

Topic category

inlandWaters

Keywords

Keyword set

keyword value

Keyword set

keyword value

originating controlled vocabulary

title

reference date

date type

revision

effective date

2011-03-25

Keyword set

keyword value

originating controlled vocabulary

title

reference date

date type

publication

effective date

2008-06-01

Geographic location

West bounding longitude

0

East bounding longitude

0.5

North bounding latitude

58.25

South bounding latitude

58

Extent

Extent group

authority code

title

reference date

date type

revision

effective date

2010-05-18

code identifying the extent

Temporal reference

Temporal extent

Begin position

2015-04-18T22:00:00.000Z

End position

2015-11-26T00:00:00.000Z

Dataset reference date

date type

publication

effective date

2020-09-10

Frequency of update

notPlanned

Quality and validity

Lineage

One hundred percent multibeam bathymetry and backscatter data were acquired in six experimental boxes and at all time points (Time 0, Time 1 and Time 2) using a Kongsberg EM2040 system operated at 300 kHz and deployed on the drop keel of the research vessel. Variations in sound velocity with water depth were determined using a CTD (Conductivity Temperature Depth) probe and applied during Multibeam data acquisition. Tidal information was gathered using a CNAV 3050 DGPS receiver. Tide height data was processed using c-Tide software and applied as a tidal correction during the processing of the bathymetry data. Survey lines were spaced at 16m across the box in an North South orientation. Two survey lines ensured 100% multibeam echosounder data coverage and overlap while a third line, in an East West orientation, was completed at each box for data quality purposes. Bathymetric data were processed for coverage and comparison using the Caris HIPS & SIPS software. Backscatter data were processed in Fledermaus geocoder tool box (FMGT) for coverage and comparison. The raw Multibeam files were processed in Caris HIPS & SIPS, which resulted in tidally corrected bathymetric soundings being produced. These soundings were hydrographically reviewed, and any erroneous soundings removed from the dataset. The time-series seabed reflectivity values (backscatter) were processed using QPS FMGT (Fledermaus GeoCoder Toolkit). This software package contains an implementation of the Geocoder algorithm which normalises and corrects the backscatter values for time varying gain, angular varying gain, and slope aspect. The resultant processed backscatter values were then analysed in ESRI ArcMap, and output imagery generated.

Conformity

Data format

name of format

version of format

Constraints related to access and use

Constraint set

Use constraints

Public data (Crown Copyright) - Open Government Licence Terms and Conditions apply

Constraint set

Limitations on public access

Public data (Crown Copyright) - Open Government Licence Terms and Conditions apply

Responsible organisations

Responsible party

contact position

Data Manager

organisation name

Centre for Environment, Fisheries & Aquaculture Science

full postal address

Cefas Lowestoft Laboratory

Pakefield Road

Lowestoft

NR33 0HT

UK

telephone number

+44 (0)1502 562244

email address

data.manager@cefas.co.uk

responsible party role

originator

Responsible party

contact position

Data Manager

organisation name

Centre for Environment, Fisheries & Aquaculture Science

full postal address

Cefas Lowestoft Laboratory

Pakefield Road

Lowestoft

NR33 0HT

UK

telephone number

+44 (0)1502 562244

email address

data.manager@cefas.co.uk

responsible party role

custodian

Metadata on metadata

Metadata point of contact

contact position

Data Manager

organisation name

Centre for Environment, Fisheries & Aquaculture Science

full postal address

Cefas Lowestoft Laboratory

Pakefield Road

Lowestoft

NR33 0HT

UK

telephone number

+44 (0)1502 562244

email address

data.manager@cefas.co.uk

responsible party role

pointOfContact

Metadata date

2020-09-10T13:29:17

Metadata language