Identification

Title

Quantitative sediment composition predictions for the north-west European continental shelf

Abstract

Spatial predictions of the fractions of mud, sand and gravel as continuous response variables for the north-west European continental shelf. Mud, sand and gravel fractions range from 0-1 (i.e. 0-100%). These fractions were generated from two additive log-ratios (ALR), ALRs and ALRm which are independent, unconstrained response variables. These raw predictions as rasters are also included presented in the attached dataset. Predicted fractions have been combined to predict the likely sediment classification based on the EUNIS level 3 sediment classification for broadscale habitats, Folk 5, Folk 7, Folk 11 and Folk 15 classification schemes. These are available as raster tif files with an ArcGIS layer file indicating the appropriate class for each raster value. For all predictions an accompanying map of the spatial distribution of error/accuracy is also included as a separate raster. For the three components of the sediment fraction a smoothed Root-Mean-Squared-Error layer is available. For the classification maps a smoothed local accuracy map is available.

Resource type

dataset

Resource locator

https://data.cefas.co.uk/view/19765

name: Cefas Data Portal

description: The Cefas Data Portal contains metadata records and data sets available to download and connect to in support of our commitment to open science. Data is available in the following formats: Binary download.

function: download

Unique resource identifier

code

CEFAS19765

codeSpace

https://data.cefas.co.uk

Dataset language

eng

Spatial reference system

code identifying the spatial reference system

Classification of spatial data and services

Topic category

environment

Keywords

Keyword set

keyword value

originating controlled vocabulary

title

reference date

date type

publication

effective date

2008-06-01

Keyword set

keyword value

originating controlled vocabulary

title

reference date

date type

publication

effective date

2008-06-01

Keyword set

keyword value

originating controlled vocabulary

title

reference date

date type

revision

effective date

2010-05-18

Keyword set

keyword value

originating controlled vocabulary

title

reference date

date type

publication

effective date

2012-01-11

Keyword set

keyword value

originating controlled vocabulary

title

reference date

date type

publication

effective date

2012-01-11

Geographic location

West bounding longitude

-13.00

East bounding longitude

11.00

North bounding latitude

63.00

South bounding latitude

48.00

Temporal reference

Temporal extent

Begin position

1990-01-01

End position

2019-01-01

Dataset reference date

date type

publication

effective date

2019-04-11

date type

revision

effective date

2024-07-12

date type

creation

effective date

2019-04-09

Frequency of update

notPlanned

Quality and validity

Lineage

Spatial predictions of mud, sand and gravel were generated for the north-west European continental shelf. Based on these fractions sediment classification maps were also generated for the study site. To support the interpretation of these layers maps of the spatial distribution of error/accuracy were also generated. In short, analysis combined the eight continuous predictive layers (Bathymetry, Bathymetric position index at a 50-pixel radii, Bathymetric position index at a 434-pixel radii, Distance from coast, Current speed at the seabed, Wave peak orbital velocity at the seabed, and suspended inorganic particulate matter for summer and winter as two separate variables) with sediment observation data in a statistical regression model to make spatial predictions of the fractions of mud, sand and gravel. Spatial predictions were generated based on two additive log-ratios that could then be back transformed to produce spatial predictions for each fraction. From these spatial predictions any classification scheme based on the percentages of mud, sand and gravel can be applied. Included here are the five classification shemes generated from these maps. The maps of accuracy were also generated to support interpretation. For the maps of the fractions of mud, sand and gravel map error was calculated based on the Root-Mean-Squared-Error of the observed vs predicted fractions from the test samples. A smoothed surface of local RMSE was then generated using the Inverse Distance Weighted (IDW) technique in ArcGIS. Each pixels’ RMSE was determined based on the closest 50 points (up to a maximum distance of 200 km). A weighting power function was applied in the IDW tool (set at 0.3) so nearer points contributed more to the pixel than distant points. For the classified maps spatial accuracy was calculated using a locally constrained confusion matrix. The IDW technique was applied to calculate a local thematic accuracy value. As above, this was applied based on the closest 50 points (maximum distance of 200 km) with a weighting power function of 0.3.

Conformity

Conformity report

specification

title

reference date

date type

publication

effective date

2013-12-10

degree

false

explanation

See the referenced specification

Conformity report

specification

title

reference date

date type

publication

effective date

2010-12-08

degree

true

explanation

See the referenced specification

Data format

name of format

Unknown

version of format

Constraints related to access and use

Constraint set

Limitations on public access

Constraint set

Limitations on public access

Responsible organisations

Responsible party

organisation name

Centre for Environment, Fisheries and Aquaculture Science, Lowestoft Laboratory (CEFAS)

full postal address

Cefas Lowestoft Laboratory

Pakefield Road

Lowestoft

NR33 0HT

UK

email address

data.manager@cefas.co.uk

responsible party role

originator

Responsible party

organisation name

Centre for Environment, Fisheries and Aquaculture Science, Lowestoft Laboratory (CEFAS)

full postal address

Cefas Lowestoft Laboratory

Pakefield Road

Lowestoft

NR33 0HT

UK

email address

data.manager@cefas.co.uk

responsible party role

custodian

Responsible party

organisation name

Centre for Environment, Fisheries and Aquaculture Science, Lowestoft Laboratory (CEFAS)

full postal address

Cefas Lowestoft Laboratory

Pakefield Road

Lowestoft

NR33 0HT

UK

email address

data.manager@cefas.co.uk

responsible party role

distributor

Responsible party

organisation name

European Commission

email address

info@publications.europa.eu

responsible party role

owner

Metadata on metadata

Metadata point of contact

organisation name

Centre for Environment, Fisheries and Aquaculture Science, Lowestoft Laboratory (CEFAS)

full postal address

Cefas Lowestoft Laboratory

Pakefield Road

Lowestoft

NR33 0HT

UK

email address

data.manager@cefas.co.uk

responsible party role

pointOfContact

Metadata date

2024-07-12T11:05:10

Metadata language