Title

IOWTOPO2 - A high resolution spherical grid topography of the Baltic Sea

Alternate title

KN172L08 SeaBeam 3012-P1 Bathymetry Grid

Date (Creation)

2001-11-27T00:00:00

Date (Revision)

2008-01-16T00:00:00

Citation identifier

IOWTOPO2

Abstract

The data sets presented here provide a digitised topography of the Baltic Sea.

Land heights and water depths have been calculated for two regular spherical grids from available data. Data set "iowtopo2" covers the whole Baltic Sea from 9° to 31° East and from 53°30’ to 66° North by (660 x 750) grid cells, see Fig. 1. The resolution is 2 minutes with respect to longitude, and 1 minute to latitude. This is approximately 1 nautical mile, or 2 km resp. The region of the Belt Sea from 9° to 15°10’ East and from 53°30’ to 56°30’ North, see Fig 2, is comprised within data set "iowtopo1" with a twofold higher resolution (1 minute in longitude and 0.5 minutes in latitude corresponding to approx. 1 km).

The data specify a representative average of the water depth or the land height of each grid cell, counted by negative and positive values in meters. Some statistical parameters allow a rough estimate of the reliability of the data. (Please be aware that data are rather uncertain in regions where strong gradients of the bottom relief occur, esp. the northern parts of the Baltic. There is an urgent need of further bathymetry data to become available for the Baltic beyond 59° North.) Since a common average of land heights and water depths lead to rather unsatisfying results with respect to the gridded shoreline, a landmask is proposed in both data sets. The landmasks were derived from the global high resolution shorelines GSHHS and RANGS, and used to get a "naturally looking" composite topography (z_topo see

below).

Citation: T. Seifert, F. Tauber, B. Kayser: 2001: "A high resolution spherical grid topography of the Baltic Sea – 2nd edition", Baltic Sea Science Congress, Stockholm 25-29. November 2001, Poster #147,

Point of contact

Organisation name	Individual name	Electronic mail address	Role
Baltic Sea Research Institute Warnemuende (IOW), Marine Geology		iowinfo@io-warnemuende.de	Product manager
Baltic Sea Research Institute Warnemuende (IOW), Marine Geology		iowinfo@io-warnemuende.de	Production center

Project name

• EMODNet Bathymetry

SeaDataNet device categories

• multi-beam echosounders

• multi-beam echosounders

SeaDataNet device categories

• Differential Global Positioning System receivers

Parameter Discovery Vocabulary (P02)

• Bathymetry and Elevation

GEMET - INSPIRE themes, version 1.0

• Hydrography

Use limitation

These data sets are a piece of scientific work which relies on free interchange of scientific data. Therefore the data are available for scientific research. The data must not be used for navigation.

Access constraints

License

Use constraints

Copyright

Other legal constraints

CC-BY (Creative Commons - Attribution)

Use limitation

These data sets are a piece of scientific work which relies on free interchange of scientific data. Therefore the data are available for scientific research. The data must not be used for navigation.

Distance

1000  Metres (m)

Language

English

Character set

UTF8

Topic category

• Oceans

Begin date

Invalid DateT09:00:00

End date

Invalid DateT09:00:00

Description

Map projection parameters, values and units :

Axes units :

UPPER LEFT X=29.3054583250

UPPER LEFT Y=44.6262830219

LOWER RIGHT X=40.7816282263

LOWER RIGHT Y=41.2281769950

WEST LONGITUDE=29° 18' 19.6500" E

NORTH LATITUDE=44° 37' 34.6189" N

EAST LONGITUDE=40° 46' 53.8616" E

SOUTH LATITUDE=41° 13' 41.4372" N

PROJ_DESC=Geographic (Latitude/Longitude) / WGS84 / arc degrees

PROJ_DATUM=WGS84

PROJ_UNITS=arc degrees

EPSG_CODE=4326

COVERED AREA=353215 sq km

Geographic identifier

EPSG / WGS84 / Geographic coordinate system / 7.4

Number of dimensions

3

Dimension name

Column

Dimension name

Row

Dimension name

Time

Dimension size

1

Cell geometry

Point

Transformation parameter availability

Checkpoint Availability

Point in Pixel

Distribution format

Name	Version
NetCDF

Distributor contact

Organisation name	Individual name	Electronic mail address	Role
Baltic Sea Research Institute Warnemuende (IOW), Marine Geology		iowinfo@io-warnemuende.de	Dissemination Unit

OnLine resource

Protocol	Linkage	Name
WWW:DOWNLOAD	https://www.io-warnemuende.de/topography-of-the-baltic-sea.html

Hierarchy level

Dataset

Statement

no information

Hierarchy level

Feature

Dataset

accuracy

Hierarchy level

Software

Description

MB-System

Other

software

Hierarchy level

Property type

Description

parameters of data processing

Statement

Data are provided in two formats. NetCDF files (*.nc) are self-desribing binaries which may be visualised and processed by tools like Ferret, Grads or Matlab. Alternatively rather big ascii files (*.dat) are given which start with two header lines and contain the following data:

xlon: the geographic longitude of the grid cell centre

ylat: the corresponding geographical latitude

z_topo: land height/water depth, composite of z_water, z_land and the proposed landmask

z_water: average of all water depths allocated from original data to this grid cell

z_land: average of land heights allocated to this grid cell from edcdaac.usgs.gov/gtopo30/gtopo30.html data

z_min: minimal value of the original data

z_max: maximal value of the original data

z_stdev: standard deviation of original data from averages z_water/z_land

z_near: datum lying nearest to the centre of this grid cell

d-near: distance of above mentioned data point from centre of grid cell

n_wet:

> 0: number of original water depths allovated to this grid cell

< 0: number of neighbors interpolated to fill this empty cell

n_dry:

> 0: number of original land heights allocated to this cell

< 0: number of iterations to find direct neighbours for interpolation

landmask: proposed "naturally loking" landmask (land=0, water=1)

flag: flag indicating a pure data average (0), or an interpolated/masked land height (+1) or water depth (-1)

Updates

1. Update from 01.05.2002

Addendum 19.07.2002

2. Update from 31.01.2003

3. Update from 30.05.2007

4. Update from 16.01.2008

A short description of the data compilation has been published on-line: https://www.io-warnemuende.de/topography-of-the-baltic-sea-data-compilation.html

Hierarchy level

Dataset

Horizontal Quality Indicator

-1 - Multisources

Vertical Quality Indicator

-1 - Multisources

Purpose Quality Indicator

2 - Bathymetric/morphologic survey

Metadata

File identifier

SDN_CPRD_116_IOWTOPO2

Metadata language

English

Character set

UTF8

Hierarchy level name

Composite Product Record

Date stamp

2020-11-24T09:28:09

Metadata standard name

ISO 19115:2003/19139 - EMODNET - BATHYMETRY

Metadata standard version

1.0

Metadata author

Organisation name	Individual name	Electronic mail address	Role
Baltic Sea Research Institute Warnemuende (IOW), Marine Geology		iowinfo@io-warnemuende.de	Author