This data set contains ice temperature and mass balance data from drifting ice buoys near the North Pole in the Central Basin of the Arctic Ocean. Buoys were deployed each April by the Pacific Marine Environmental Laboratory (PMEL) and the Cold Regions Research and Engineering Laboratory (CRREL). The buoys drifted with the ice pack, and data were collected via satellite transmissions. Ice temperature data were collected year around during 2000-2003, at 10 cm depth intervals twice daily, every twelve hours.
The North Pole Environmental Observatory (NPEO) is a year-round, automated scientific observatory, deploying various instruments each April in order to learn how the world's northernmost sea helps regulate global climate. It consists of a set of unmanned scientific platforms that record oceanographic, cryospheric, and atmospheric data throughout the year. More information about the project is available at the project Web site, North Pole Environmental Observatory (http://psc.apl.washington.edu/northpole/).
Data are in tab-delimited ASCII text format. Data are distributed as a 170 KB compressed file available for ordering via NCAR.
Morison, J. H., K. Aagaard, R. Moritz, A. Heiberg, M. Steele, M. McPhee, J. Overland, S. Salo, D. Perovich, J. Richter-Menge, and B. Elder. 2006. North Pole Environmental Observatory PMEL/CRREL 2000-2003 ice temperature and mass balance buoy data. Boulder, CO: National Center for Atmospheric Research. ARCSS Data Archive.
| Category | Description |
|---|---|
| Data format | Data are in tab-delimited ASCII text format. |
| Spatial coverage and resolution | Southernmost Latitude: 71.026° N Data were collected at 10 cm intervals from 70 cm above ice surface to 370 cm below ice surface. |
| Temporal coverage and resolution | Coverage is from 20 April 2000 to 28 February 2003. Data were recorded twice daily at 12-hour intervals. |
| File naming convention | File names identify the beginning year of the observation period, the buoy number, and the type of data. See Directory Structure and File Naming Convention. |
| File size | Files range in size from 4 KB to 240 KB. Total data size is 996 KB. Data are distributed as a 170 KB compressed (.zip) file. |
| Parameter(s) | Ice temperature, mass balance |
| Procedures for obtaining data | Data are available for ordering through NCAR. |
1. Contacts and Acknowledgments
2. Detailed Data Description
3. Data Access and Tools
4. Data Acquisition and Processing
5. References and Related Publications
6. Document Information
James H. Morison
Polar Science Center
Applied Physics Laboratory
University of Washington
Seattle, WA
USA
Knut Aagaard
Polar Science Center
Applied Physics Laboratory
University of Washington
Seattle, WA
USA
Richard Moritz
Polar Science Center
Applied Physics Laboratory
University of Washington
Seattle, WA
USA
Andreas Heiberg
Polar Science Center
Applied Physics Laboratory
University of Washington
Seattle, WA
USA
Michael Steele
Polar Science Center
Applied Physics Laboratory
University of Washington
Seattle, WA
USA
Miles McPhee
McPhee Research Company
Naches, WA
USA
James Overland
Pacific Marine Environmental Laboratory
National Oceanographic and Atmospheric Administration
Seattle, WA
USA
Sigrid Salo
Pacific Marine Environmental Laboratory
National Oceanographic and Atmospheric Administration
Seattle, WA
USA
Don Perovich
Cold Regions Research and Engineering Laboratory
Hanover, NH
USA
Jacqueline Richter-Menge
Cold Regions Research and Engineering Laboratory
Hanover, NH
USA
Bruce Elder
Cold Regions Research and Engineering Laboratory
Hanover, NH
USA
Roger Andersen
Applied Physics Laboratory
University of Washington
Seattle, WA
USA
This research was supported by the National Science Foundation (NSF) Office of Polar Programs (OPP) Arctic System Science (ARCSS) Program grant OPP-9910305.
Data are in tab-delimited or space-delimited ASCII text format.
Each year, measurements began in April and continued through February or March of the following year. The year 2001 is an exception; measurements began in April 2001 and ceased in November 2001.
| Directory and File Name | Description |
| NPEO2000-2002_IceBuoys_ReadMe.txt | |
| nsidc_readme.txt | |
| NP2000_CRREL_Ice_Buoys/ | Researchers reported temperatures from two buoys; the directory includes a separate temperature and position file for each buoy. Buoys are identified by their numbers. |
| NPEO2000_20726.pos.txt | This position file contains a header identifying the measurement season and the buoy number. Rows represent the twice-daily recording of position. Columns indicate date, time, latitude, and longitude. |
| NPEO2000_20726_Ice.temp.txt | This temperature file includes a header identifying the measurement season and the buoy number. Each row of the temperature files represents one of two daily measurement times; column headers indicate date, time, and measurement depths. |
| NPEO2000_22206.pos.txt | This position file contains a header identifying the measurement season and the buoy number. Rows represent the twice-daily recording of position. Columns indicate date, time, latitude, and longitude. |
| NPEO2000_22206_Ice.temp.txt | This temperature file includes a header identifying the measurement season and the buoy number. Each row of the temperature files represents one of two daily measurement times; column headers indicate date, time, and measurement depths. |
| NP2001_CRREL_Ice_Buoys/ | Researchers reported temperature from a single buoy. Data collection ceased in November 2001. The directory includes two files, one containing temperature and one containing position data. |
| NPEO2001_22203.pos.txt | This position file contains a header identifying the measurement season and the buoy number. Rows represent the twice-daily recording of position. Columns indicate date, time, latitude, and longitude. |
| NPEO2001_22203_Ice.temp.txt | This temperature file includes a header identifying the measurement season and the buoy number. Each row of the temperature files represents one of two daily measurement times; column headers indicate date, time, and measurement depths. |
| NP2002_CRREL_Ice_Buoys/ | Researchers reported temperatures from two buoys, which are contained in two separate temperature files. One buoy also recorded mass balance data, provided in a third file. A fourth file specifies position, which was the same for both buoys this season, so only one position file is included. |
| NPEO2002_09120_Ice.temp.txt | This temperature file includes a header identifying the measurement season and the buoy number. Each row of the temperature files represents one of two daily measurement times; column headers indicate date, time, and measurement depths. |
| NPEO2002_21078_Ice.snd.txt | This mass balance file includes a header identifying the buoy from which acoustic measurements were taken, and explaining the data columns. The data consist of four columns: date of sounding; time of sounding; distance (cm) of top surface from deployment; and distance (cm) of bottom surface from deployment. |
| NPEO2002_21078_Ice.temp.txt | This temperature file includes a header identifying the measurement season and the buoy number. Each row of the temperature files represents one of two daily measurement times; column headers indicate date, time, and measurement depths. This file contains ice temperature data from buoy number 21078 for the April 2002-March 2003 season. |
| NPEO2002_icebuoys.pos.txt | This position file contains a header identifying the measurement season and the buoy number. Rows represent the twice-daily recording of position. Columns indicate date, time, latitude, and longitude. |
Files range in size from 4 KB to 240 KB. Total data size is 996 KB. Data are distributed as a 170 KB compressed (.zip) file.
Southernmost Latitude: 71.026° N
Northernmost Latitude: 89.689° N
Westernmost Longitude: 169.041° W
Easternmost Longitude: 87.6176° E
Temperature data were obtained at 10 cm intervals, from 70 cm above ice surface to 370 cm below ice surface.
Data were collected from 20 April 2000 to 28 February 2003.
Observations were recorded twice daily, at 12-hour intervals.
Ice Temperature
The temperature data consist of temperature (°C) from the air through the ice into the ocean beneath, typically every 10 cm and every 12 hours. In the temperature files, a header indicates the heights/depths at which temperature was measured. A depth of 0 is the position at the top of the ice at the time of deployment; positive depth numbers are heights above the surface of the ice; negative depth numbers are depths below the top surface of the ice.
Mass Balance
Mass balance buoys measured two distances with acoustic pingers. They recorded the distance (cm) from the surface snow and ice to a pinger mounted on a post ("top surface"), and the distance from the bottom of the ice to an upward-looking underwater pinger ("bottom surface").
Position
Buoy positions were determined every hour by a GPS unit mounted on each buoy. The position data given in the .pos files are the buoy positions at 1100 and 2300 GMT.
The following is a sample of the 2001 temperature file NPEO2001_22203_Ice.temp.txt:
| Distance from Ice surface (cm) at deployment | ||||||||
| Date | 60 | 50 | 40 | 30 | 20 | 10 | 0 | -10 |
| # | ||||||||
| 4/14/01 11:30 | -27.5 | -27.74 | -27.5 | -27.56 | -27.26 | -27.02 | -26.78 | -24.11 |
| 4/14/01 23:30 | -28.3 | -28.49 | -28.56 | -28.43 | -28.18 | -25.13 | -27.68 | -24.85 |
| 4/15/01 11:30 | -27.32 | -27.51 | -27.2 | -27.26 | -26.96 | -26.84 | -27.14 | -25.95 |
| 4/15/01 23:30 | -28.75 | -28.56 | -28.44 | -28.56 | -28.62 | -27.69 | -27.82 | -26.3 |
| 4/16/01 11:30 | -26.41 | -26.59 | -26.35 | -26.35 | -26.17 | -25.88 | -25.71 | -24.61 |
Note: Only 9 of 44 columns are shown in the example above. Text header information is not shown.
Missing data are indicated by "1.e35" in the data files. Data may be missing for an entire day, or for particular heights/depths.
In 2002, the GPS units in both ice buoys failed. The position file included for 2002 (NPEO2002_icebuoys.pos) is from the weather station buoy 22207, which was deployed on the same floe.
These data are preliminary, until further notice from the investigators. Preliminary data are subject to further review and quality control. This document will reflect any updates from the investigators.
Data are available for ordering through NCAR.
The Mass Balance Buoy (also called the ice-temperature buoy, the PMEL/CRREL buoy or Drifting buoy) includes an acoustic pinger mounted on a post that measures the depth of the snow on top of the sea ice, and the distance from the bottom of the ice to an upward-looking underwater pinger. It also includes a chain of thermistors which measure temperatures from the air down through the snow cover, through the sea ice and into the sea water below the ice. The chain is several meters long, and has temperature sensors every 5-10 cm. The buoy drifts with the sea arctic ice.
Sensors mounted on the buoys automatically recorded data twice daily. Data were transmitted by the NOAA Argos Data Collection System on the ARGOS satellite.
None available.
ARCSS: Arctic System Science Program
ASCII: American Standard Code for Information Interchange
ARGOS: Advanced Research and Global Observation Satellite
CRREL: Cold Regions Research and Engineering Laboratory
FTP: File Transfer Protocol
GMT: Greenwich Mean Time
GPS: Global Positioning System
J-CAD: JAMSTEC Compact Arctic Drifter
JAMSTEC: Japan Marine Science and Technology Center
NCAR: National Center for Atmospheric Research
NOAA: National Oceanographic and Atmospheric Administration
NPEO: North Pole Environmental Observatory
NSF: National Science Foundation
OPP: Office of Polar Programs
PMEL: Pacific Marine Environmental Laboratory
URL: Uniform Resource Locator
July 2006
http://data.eol.ucar.edu/codiac/dss/id=106.ARCSS128