IceBridge NSERC L1B Geolocated Meteorologic and Surface Temperature Data

This data set is a collection of airborne in-flight meteorological and in-cabin measurements and thermal emission measurements of near-nadir surface skin temperature taken over Antarctica and Greenland from 12 October 2009 to the present. The data were collected as part of NASA Operation IceBridge funded campaigns.

Operation IceBridge products may include test flight data that are not useful for research and scientific analysis. Test flights usually occur at the beginning of campaigns. Users should read flight reports for the flights that collected any of the data they intend to use. Check IceBridge campaign Flight Reports for dates and information about test flights.

Contacts and Acknowledgments
Detailed Data Description
Data Access and Tools
Data Acquisition and Processing
References and Related Publications
Document Information

Citing These Data

The following example shows how to cite the use of this data set in a publication. For more information, see our Use and Copyright Web page.

Shetter, Rick, Eric Buzay, and David Van Gilst. 2010, updated current year. IceBridge NSERC L1B Geolocated Meteorologic and Surface Temperature Data, [indicate subset used]. Boulder, Colorado USA: NASA DAAC at NSIDC. http://nsidc.org/data/iamet1b.html.

Overview

Platform	Douglas DC-8
Sensor	Cabin pressure transducer 3-stage hygrometer 2-stage hygrometer Total air temperature sensor Infrared surface temperature pyrometer
Spatial Coverage	Arctic / Greenland: Southernmost Latitude: 60° N Northernmost Latitude: 90° N Westernmost Longitude: 180° W Easternmost Longitude: 180° E Antarctica: Southernmost Latitude: 90° S Northernmost Latitude: 53° S Westernmost Longitude: 180° W Easternmost Longitude: 180° E
Spatial Resolution	Varies by instrument parameter and aircraft flight characteristics
Temporal Coverage	12 October 2009 to the present
Temporal Resolution	Seasonal
Parameters	Meteorological Surface temperature Positional measurements
Data Format	ICARTT comma delimited text files
Metadata Access	View Metadata Record
Data Access	FTP

1. Contacts and Acknowledgments

Investigator(s) Name and Title

Rick Shetter, Eric Buzay, and David Van Gilst
University of North Dakota
National Suborbital Education and Research Center
4149 University Avenue Stop 9011
Grand Forks, ND
58202-9011 USA

Technical Contact

NSIDC User Services
National Snow and Ice Data Center
CIRES, 449 UCB
University of Colorado
Boulder, CO 80309-0449 USA
phone: +1 303.492.6199
fax: +1 303.492.2468
form: Contact NSIDC User Services
e-mail: nsidc@nsidc.org

Acknowledgements

NASA Airborne Science

NASA Langley Research Center - ICARTT File Format Scanning by Ali Aknan

2. Detailed Data Description

Format

The NSERC L1B Geolocated Meteorologic and Surface Temperature data files are ICARTT comma delimited text files.

File and Directory Structure

Data files are organized on the FTP site, ftp://n4ftl01u.ecs.nasa.gov/SAN2/ICEBRIDGE_FTP/, as described in Figure 1.

Figure 1. Directory Structure

File Naming Convention

The data files are named according to the following convention and as described in Table 2:

IAMET1B_nav_dc8_20121002_R0.ict

IAMET1B_nav_dc8_YYYYMMDD_r1.ict

Where:

**Table 2.** File Naming Convention Description
Variable	Description
IAMET1B	Short name for IceBridge NSERC L1B Geolocated Meteorologic and Surface Temperature Data
nav	Navigation, aircraft, and facility instrumentation data
dc8	NASA Dryden DC-8 airborne laboratory aircraft
YYYY	Four-digit year of data collection
MM	Two-digit month of data collection
DD	Two-digit day of data collection
r1	Data revision 1
.ict	Indicates ICARRT data file

File Size

Data files range from approximately 1 MB to 12 MB.

Volume

Data volume for the full data set is approximately 883 MB.

Spatial Coverage

Spatial coverage for the IceBridge NSERC L1B Geolocated Meteorologic and Surface Temperature campaigns include the Greenland and Antarctic areas. In effect, this represents the two coverages noted below.

Arctic / Greenland:
Southernmost Latitude: 60° N
Northernmost Latitude: 90° N
Westernmost Longitude: 180° W
Easternmost Longitude: 180° E

Antarctica:
Southernmost Latitude: 90° S
Northernmost Latitude: 53° S
Westernmost Longitude: 180° W
Easternmost Longitude: 180° E

Spatial Resolution

Spatial resolution varies by instrument parameter and aircraft flight characteristics.

Projection and Grid Description

These data are provided in unprojected geographic coordinates using the WGS84 vertical datum.

Temporal Coverage

These data were collected as part of NASA Operation IceBridge funded campaigns from 12 October 2009 to the present.

Temporal Resolution

IceBridge campaigns are conducted on an annual repeating basis. Arctic and Greenland campaigns are conducted during March, April, and May; and Antarctic campaigns are conducted during October and November.

NSERC L1B Geolocated Meteorologic and Surface Temperature data are captured once per second.

Parameter or Variable

The NSERC L1B Geolocated Meteorologic and Surface Temperature data set contains meteorological and in-cabin measurements and thermal emission measurements.

Parameter Description

Data parameters vary between campaigns. Please see the following parameter descriptions for each campaign:

3. Data Access and Tools

Data Access

Data are available via FTP.

Software and Tools

NSIDC provides a MATLAB reader that reads NSERC L1B Geolocated Meteorologic and Surface Temperature Data files. The data files also may be opened by any ASCII text reader.

4. Data Acquisition and Processing

Data Acquisition Methods

The DC-8 data set is collected from a number of sources. All of the navigation data comes from the Air Data Computer, Flight Management System, and GPS receivers. The parameters from the Air Data Computer and Flight Management System are recorded using dual NASDAT flight recorders via ARINC-429 data bus. The flight recorders are located in the housekeeping rack.

The flight recorders also record the analog voltage output data from the facility instruments located on board, including pressure transducer, hygrometers, and infrared pyrometer. All parameters are recorded at one hertz for the entire duration of the flight.

Derivation Techniques and Algorithms

Data are taken at one hertz from aircraft instruments and facility instruments onboard. Data are recorded on two redundant NASA Airborne Science Data Acquisition and Transmission (NASDAT) flight recorders. No special techniques or algorithms are used in this data set.

Processing Steps

The following processing steps are performed by the data provider.

Obtain flight specific files from flight recorder (NASDAT).
Convert to ASCII ICARTT format.
Perform quality control on the data set using graphs and curve fitting.
Output final quality controlled ICARTT file.

Error Sources

Some data sets have missing data parameters due to either a fault in the system, or data is out of range for respective instruments. Missing parameters are marked with a -99999 label.

Sensor or Instrument Description

Instruments used for the collection of this data include the following:

MKS Baratron Type 220D Pressure Transducer (Cabin Pressure)

The MKS Baratron Pressure Transducer is used to measure the pressure within the cabin of the aircraft. Based on a reference pressure which remains constant within the instrument, the exterior pressure can then be measured. The pressure transducer has a resolution of 1 Torr and the accuracy is ± 0.15 percent of Reading ±temperature coefficient. The temperature coefficient is 0.02 percent of Reading / °C.

2-Stage Hygrometer Buck Research Instruments Model 1011B (Dew/Frost Point)

The Buck Research Hygrometer system is a chilled-mirror type hygrometer designed for airborne measurements of dew and frost point temperatures. It is capable of measuring dew/frost points between -75°C and +50°C, over a wide range of temperatures, pressures, and airspeeds. The accuracy of this system is ± 0.1°C.

3-Stage Hygrometer Model 137 Vigilant by Edgetech (Dew Point)

The Edgetech Model 137 Hygrometer is a rugged, shock mounted instrument used for dew point measurement. This model measures dew point only, including dew points measured below zero degrees Celsius. The dew point is measured using chill mirror technology assuring precision accuracy, repeatability and reliability. The Edgetech hygrometer is able to accurately detect the dew point within the range of -50°C to 90°C with an accuracy of ± 0.2°C and precision of 0.1°C. The sensor is capable of a 65°C depression from an ambient temperature of 25°C.

Total Air Temperature Goodrich (Rosemount) model 102

Total air temperature is measured by a Rosemount probe and Goodrich Sensor mounted on the surface of the aircraft. The total air temperature sensor can measure temperature between -70°C to +70°C with a speed of up to Mach 3 at altitudes between 0 to 100,000 feet. The accuracy of the total air temperature is ± 1.0466 degrees Celsius.

Heitronics Infrared Radiation Pyrometer KT-19.85II

The Heitronics Infrared Radiation Pyrometer is a remotely sensed measuring transducer that receives the infrared radiation emitted by the measuring object and transforms it into a standardized output signal. The pyrometer is located on the bottom of the aircraft to measure surface and cloud top temperatures. It has a spectral range of 9.6 to 11.5 μm, a response time of one second, and a temperature range of -100° to +200°C. The accuracy is ± 0.5 percent plus 0.7 percent of the difference between target temperature and housing temperature.

5. References and Related Publications

Related Data Collections

IceBridge POS/AV L1B Corrected Position and Attitude Data

Related Web Sites

6. Document Information

Acronyms and Abbreviations

The acronyms used in this document are listed in Table 3.

**Table 3.** Acronyms and Abbreviations
Acronym	Description
ASCII	American Standard Code for Information Interchange
CIRES	Cooperative Institute for Research in Environmental Science
FTP	File Transfer Protocol
ICARTT	Intercontinental Chemical Transport Experiment
L1B	Processing Level 1B
NASA	National Aeronautics and Space Administration
NASDAT	NASA Airborne Science Data Acquisition and Transmission flight recorders (NASDAT)
NSIDC	National Snow and Ice Data Center
NSERC	National Suborbital Education & Research Center
URL	Uniform Resource Locator
UTC	Universal Time Code
WGS-84	World Geodetic System 1984

Document Creation Date

12 April 2011

Document Revision Date

19 September 2011
17 May 2012
07 March 2013

Document URL

http://nsidc.org/data/docs/daac/icebridge/iamet1b/index.html

Service Interruption

National Snow and Ice Data Center