Data Set ID:

Baltic Sea Experiment (BALTEX) Ground-Based Radar Polar Volume Data, Version 1

This data set includes non-Doppler polar volume reflectivity data from the Baltic Sea Experiment (BALTEX). Data were collected on Sweden's Gotland Island, using an Ericsson radar mounted at 56 m above sea level.

This is the most recent version of these data.

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Data: Data integrity verified

Documentation: Key metadata and links to supporting documentation available

User Support: Assistance with data access and basic data usage

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Data Format(s):
  • NetCDF
Spatial Coverage:
N: 57.24, 
S: 57.24, 
E: 18.39, 
W: 18.39
Spatial Resolution:Not SpecifiedSensor(s):RADAR
Temporal Coverage:
  • 1 September 2002 to 31 May 2003
Temporal ResolutionNot specifiedMetadata XML:View Metadata Record
Data Contributor(s):Ralf Bennartz, Daniel Michelson

Geographic Coverage

Once you have logged in, you will be able to click and download files via a Web browser. There are also options for downloading via a command line or client. For more detailed instructions, please see Options Available for Bulk Downloading Data from HTTPS with Earthdata Login.

As a condition of using these data, you must cite the use of this data set using the following citation. For more information, see our Use and Copyright Web page.

Bennartz, R. 2004. Baltic Sea Experiment (BALTEX) Ground-Based Radar Polar Volume Data, Version 1. [Indicate subset used]. Boulder, Colorado USA. NASA National Snow and Ice Data Center Distributed Active Archive Center. doi: [Date Accessed].

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Detailed Data Description


Data are provided in netCDF format. The netCDF headers contain dimensions, units, and other information.

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File and Directory Structure

There is a tar file on the HTTPS site for each month data were collected.

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File Naming Convention

File strings describe file contents, including the non-doppler radar (znp), place, date, and time. For instance, the file "" indicates that the data were collected from Hemse radar station at 1 hour 45 minutes in UTC on 31 May 31 2003.

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File Size

Each data file is 2.3 MB.

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Data files are contained in compressed tar files, one file for each month. The total compressed volume is 212 MB.

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Spatial Coverage

57.24°N, 18.39°E

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Temporal Coverage

1 September 2002 to 31 May, 2003.

Temporal Resolution

Data are given in 15-minute intervals.

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Parameter or Variable

Parameter Description

The parameter measured in this data set is reflectivity.

The following table shows the scanning angle for the 12 scans in each data file.

Scan Angle
(elevation angle in degrees)
1 0.5
2 0.7
3 0.9
4 1.1
5 1.5
6 2.3
7 3.2
8 4.1
9 6.0
10 12.0
11 24.0
12 40.0

Unit of Measurement

Reflectivity is given in dBz.

Parameter Source

The measurements were taken from the Gotland Island Hemse radar station.

Sample Data Record

The following shows scan 1 of the data file ""

Scan 1 figure

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Software and Tools

Software and Tools

Use an appropriate application to view netCDF data.

The netCDF format is an interface for array-oriented data access with an interface library. The netCDF library also defines a machine-independent format for representing scientific data. Together, the interface, library, and format support creating, accessing, and sharing scientific data. The netCDF software was developed at the Unidata Program Center in Boulder, Colorado. More information about netCDF and software for manipulating and displaying NetCDF is available from Unidata.

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Data Acquisition and Processing

Data Acquisition Methods

The following table provides information about the Hemse radar station, the instrument, and data acquisition.

Radar System Ericsson EWR Radar
Wavelength 5.31 cm
Location Gotland Island (57.24 ° North, 18.39 ° East), Sweden
Processing Software Ericsson Enterprise Wireless Internet Solutions (EWIS)
Height of the antenna 56 m above sea level
Distance between two successive range bins 2,000 m
Number of range bins in each ray 120 (with 2,000 m spacing)
Number of azimuth gates (rays) per scan 480 (starting North, clockwise)
Half-power beamwidth 0.9 °
Antenna speed in revolutions per minute 6
Pulse width 2 ms
Low-pulse repetition frequency 250 Hz
High-pulse repetition frequency 250 Hz
How raw data in range are processed to arrive at the given value average
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References and Related Publications

Contacts and Acknowledgments

Ralf Bennartz
University of Wisconsin-Madison
Daniel Michelson
Swedish Meteorological and Hydrological Institute

Document Information


April 2004

No technical references available for this data set.

How To

V0 Programmatic Data Access Guide
Data from the NASA National Snow and Ice Data Center Distributed Active Archive Center (NSIDC DAAC) can be accessed directly from our HTTPS file system. We provide basic command line Wget and curl instructions for HTTPS file system downloads below. For questions about programmatic access to NSIDC... read more