North Pole Environmental Observatory Aerial CTD Survey

Summary

This data set includes conductivity, temperature, depth (CTD), pressure, salinity, potential temperature, and density data, which were collected yearly, 2000 to 2006, in the Arctic Ocean as part of the North Pole Environmental Observatory. Investigators landed a helicopter or skiplane on the arctic sea ice and took measurements using a Seabird SBE-19 Seacat with a portable winch.They processed the data using the SEASOFT recipe to minimize salinity spiking and correct for a thermal lag of the conductivity cell. Certain constants were determined by empirical trial, which differed slightly for each year.

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 and are available for ordering through NCAR.

Citing These Data

Morison, J., Steele, M., and K. Falkner. 2002, updated 2006. North Pole Environmental Observatory aerial CTD survey. Boulder, Colorado USA: National Center for Atmospheric Research.

Overview Table

Table of Contents

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

1. Contacts and Acknowledgments

Investigators

James Morison
Polar Science Center, Applied Physics Lab
University of Washington
1013 NE 40th
Seattle, WA 98105-6698
USA

Michael Steele
Polar Science Center, Applied Physics Lab
University of Washington
1013 NE 40th
Seattle, WA 98105-6698
USA

Kelly K. Falkner
Oregon State University
College of Oceanic and Atmospheric Sciences
104 Ocean Admin Building
Corvallis, OR 97331-5503
USA

Acknowledgements

This research was supported by the National Science Foundation (NSF) Office of Polar Programs (OPP) Arctic System Science (ARCSS) Program grant OPP-9910305.

2. Detailed Data Description

Format

Data are in tab-delimited ASCII format. Each column has a short, descriptive header.

Depth (m)
Pressure (dbar)
In situ temperature (ºC)
Conductivity (S/m)
Salinity (psu)
Potential Temperature (deg C)
Density (sigma-theta)

Note: Investigators did not record data for all seven of these parameters for each deployment.

File and Directory Naming Convention

File names follow the convention NPEOyyyy_CTDn_llll.txt, where yyyy is the year the data were collected, n is the cast number, and llll (where applicable) gives station location information. Directory names follow the convention NPEOyyyy_CTDs where yyyy is the year the data were collected. Investigator-provided documentation files can be found with the data for each year, and their names follow the convention NPEO_yyyy_CTDs_ReadMe.txt.

Spatial Coverage

Southernmost Latitude: 84.892° N
Northernmost Latitude: 89.977° N
Westernmost Longitude: 179.882° W
Easternmost Longitude: 179.847° E

Spatial Resolution

Data were collected approximately every 30 cm to a depth of 500 m.

Temporal Coverage

Investigators collected these data during yearly spring deployments, over the years 2000-2008.

Parameter or Variable

Investigators collected depth, pressure, in situ temperature, conductivity, salinity, potential temperature, and density data.

Sample Data Record

This data sample is from NPEO2005_CTD6_90N.txt.

Quality Assessment

See investigator-provided documentation for quality assessment information from each yearly deployment.

3. Data Access and Tools

Data Access

Data are available for ordering from NCAR.

Volume

The collective volume of the entire data set is approximately 8.58 MB.

Related Data Collections

• North Pole Environmental Observatory
• North Pole Environmental Observatory (NPEO) Oceanographic Mooring Data, 2001-2002
• North Pole Environmental Observatory (NPEO) Weather and Radiation Buoy Data, 2002-2004
• North Pole Environmental Observatory PMEL/CRREL 2000-2003 Ice Temperature and Mass Balance Buoy Data
• JCAD Drifting Buoy Data, Arctic Ocean, 2000-2002
• Circulation in the Freshwater Switchyard of the Arctic Ocean: Helicopter CTD Profile Data 2003-2005

4. Data Acquisition and Processing

See investigator-provided documentation for data acquisition and processing information, including instrument descriptions, from each yearly deployment.

5. References and Related Publications

Morison, J., R. Andersen, N. Larson, E. D'Asaro, and T. Boyd. 1994. The Correction for Thermal-Lag Effects in Sea-Bird CTD Data. Journal Atmospheric and Oceanic Technology 11:1151-1164.

6. Document Information

Acronyms and Abbreviations

The following acronyms and abbreviations are used in this document:

Document Creation Date

July 2003

Document Revision Date

June 2010

Document URL

http://data.eol.ucar.edu/codiac/dss/id=106.ARCSS088