Climate and Flux Data from Alaska Sites, 1998-2000

Summary

This data set contains climate, flux, and bulk density data from Ivotuk and Council (Seward Peninsula), Alaska, USA, collected from 1998 through 2000.

Surface energy and trace gas exchange measurements were made at each of the four Ivotuk sites using the eddy covariance technique.

Three flux and climate towers operated at Council, Seward Peninsula, during 1999 and 2000. Two towers were located at the tundra and forest sites. The third tower was a mobile tower and during 1999 covered four different surface types: lowshrub, shrub, woodland, and burned tundra. During 2000, the mobile tower covered tall shrub, tundra ISS2, burned tundra, heath and shallow thaw lake. The data have been divided by surface type or site and by data type (flux or climate). The data set also includes mean bulk density measurements for soil layers, collected in 1999.

Measurements were taken as part of the Land-Atmosphere-Ice Interactions Arctic Transitions in the Land-Atmosphere System (LAII-ATLAS) program. The research project was funded by the Arctic System Sciences (ARCSS) Program, grant number OPP-9818066.

Data are available for ordering through NCAR.

Citing These Data:

Beringer, J., F.S. Chapin III, C. Copass. 2003. Climate and Flux Data from Alaska Sites, 1998-2000. Boulder, CO: National Center for Atmospheric Research, ARCSS Data Archive.

Overview Table

Table of Contents

1. Contacts and Acknowledgments
2. Detailed Data Description
3. Document Information

1. Contacts and Acknowledgments:

Investigator(s) Name and Title:

Dr. Jason Beringer
School of Geography and Environmental Science
P.O. Box 11A
Monash University
Clayton, Victoria, 3800
Australia

Dr. F.S. Chapin III
Institute of Arctic Biology
311 Irving, I Bldg
University of Alaska Fairbanks
Fairbanks, Alaska 99775-7000
USA

Catherine Copass
Institute of Arctic Biology
311 Irving, I Bldg
University of Alaska Fairbanks
Fairbanks, Alaska 99775-7000
USA

2. Detailed Data Description:

Format:

Data are available as comma-delimited text files.

File Naming Convention:

Each file is named according to the name of the site, data type, and date of collection. Site names are I (Ivotuk) and Council (C). Data types and abbreviations are as follows:

For example,

• "cfore_climate_99.txt" contains data from the Council forest (C1) site, climate data, collected in 1999.
• "imoss_flux_98.txt" contains data from the Ivotuk moss site (site 4), flux data, collected in 1998.

Additionally, there are three tab-delimited text files which contain site and column heading information for the data files, as listed below:

• "ivotuk_98_column_definitions.txt" contains column definitions for Ivotuk 1998 data.
• "council_99_column_definitions.txt" contains column definitions for Council 1999 data.
• "council_00_column_definitions.txt" contains column definitions for Council 2000 data.

The file bdsumry_99.txt contains bulk density data collected at the Council site in 1999.

File Size:

File sizes range from 35 KB to 1,313 KB. The tar file containing all data is 9.4 MB.

Spatial Coverage:

Data were collected from various sites located within three different regions in Alaska. The collection sites were located as follows:

Ivotuk 1998

Site 1, moist acidic tundra (MAT) site: 68.480º N, 155.745º W
Site 2, moist non-acidic tundra (MNT) site: 68.487 N, 155.743 W
Site 3, shrub site: 68.487º N, Longitude: 155.743º W
Site 4, moss site: 68.480º N, Longitude: 155.745º W

Council 1999

Site C1, spruce forest: 64.843º N, 163.705º W
Site C2, tundra: 64.891º N, 163.644º W
Site C3, shrub: 64.746º N, 163.894º W
Site C4, woodland: 64.746º N, 163.894º W
Site C6, lowshrub: 64.746º N, 163.894º W
Site C8, burned tundra: 64.746º N, 163.894º W

Council 2000

Site C1, spruce forest (CFORE): 64.843º N, 163.705º W
Site C2 site, tundra (CTUND): 64.891º N, 163.644º W
Site C3, shrub (CSHRB): 64.746º N, 163.894º W
Site C8, burned tundra (CBURN): 64.746º N, 163.894º W
Site CISS2, second tundra site at NCAR ISS site: 64.746º N, 163.894º W
Site CHEAT, heath: 64.746º N, 163.894º W
Site CLAKE, shallow lake

Temporal Coverage:

The data were collected at Ivotuk from 1998-06-27 to 1998-08-11, and at Council from 1999-06-18 to 2000-08-30, during summer field seasons only.

Temporal Resolution:

Data are reported as 30-minute averages.

Parameters or Variables:

Parameter Description:

The parameters measured varied among the sites and include the following: Canopy cover, surface energy, trace gas exchange, three-dimentional wind velocity, turbulent fluctuations of carbon dioxide and water, air temperature, wind speed, vapor pressure deficit, water vapor content, soil moisture, soil bulk density, incoming and reflected short-wave radiation, incoming and emitted long-wave radiation, net radiation, and ground heat flux.

Detailed Information on Ivotuk Data Collection

Surface energy and trace gas exchange measurements were made at each site using the eddy covariance technique. The MAT site was operated continuously over the growing season, while the remaining sites were characterized by a single tower that was moved from site to site. The MAT site is therefore used as a reference.

Tower-based microclimatic and eddy-covariance measurements were used to characterize the radiation balance and energy budget above different tundra types. Two towers were developed for this measurement campaign. Simultaneous measurements of energy and trace gas exchanges were made at both over the entire growing season using the eddy covariance technique. Measurements at the other sites were measured consecutively but in parallel to the MAT site.

Three-meter towers were used at all sites. Radiation measurements were made as close as practical to the top of the towers to minimize the potential of shading from above and to maximize the surface area within the effective sensor footprint. Eddy-covariance measurements were made at varying heights above the vegetation.

Detailed Information on Ivotuk Data Format

Data are divided into two categories: climate and flux. The data files contain varying parameters, indicated by column headings. Please refer to the file "ivotuk_98_column_definitions.txt" for definitions of the column headings.

Note: each flux file contains a VALID column (VALIDS or VALIDM), which is a flag to indicate good quality data. Data with a designation of 1 are identified as good data.

Detailed Information on Council Data Collection

Data were collected at Council on the Seward Peninsula, located approximately 70 miles to the northeast of Nome. The Peninsula itself encompasses a diversity of landscape and ecosystem types created by the various climatic and topographical settings.

Three towers were deployed to obtain microclimatic and eddy-covariance measurements in order to characterize the radiation, energy and trace gas exchanges above the different vegetation types. Simultaneous measurements of radiation, energy and trace gas exchanges were made at both the tundra and forest sites over the entire growing season using the eddy covariance technique. The tundra tower was used as a reference tower to compare with the various mobile sites because it had the most complete data set. The third mobile tower was deployed to collect measurements consecutively at the woodland, low shrub and shrub sites during 1999, and at the tall shrub, ISS2, burn, heath and lake sites during 2000, but during the same period as the tundra site for both years of collection.

Ten-meter towers were used at all sites except at the forest site where the tower was 20 m. Radiation measurements were made as close as practical to the top of the towers to minimize the potential of shading from above and to maximize the surface area within the effective sensor footprint. Eddy-covariance measurements were made at varying heights above the vegetation.

For bulk density measurements, samples of the moss, fibric, humic, and mineral layers were collected using a large (30-cm diameter) soil corer. At least 3 cm of each layer was collected. Care was taken not to compress the samples. Total volume of the sample was recorded. Samples were then weighed, dried, and weighed again to obtain bulk density (g/cm-3).

Detailed Information on Council Data Format

Data are divided into two categories: climate and flux. Additionally, mean bulk density measurements were collected for the soil layers at each of the sites measured in 1999. The data files contain varying parameters, indicated by column headings. Please refer to the files "council_99_column_definitions.txt" and "council_00_column_definitions.txt" for specific site information and definitions of the column headings.

Note: each flux file contains a VALID column (MVALIDY, M_VALIDY, TVALIDY, T_VALIDY, FVALIDY, F_VALIDY), which is a flag to indicate good quality data. Data with a designation of 8 are identified as good data.

Sample Data Record:

Sample Flux Data for the Council Shrub Site, 2000:

3. Document Information:

Document Creation Date:

2003-05-20

Document Revision Date:

Document Review Date:

Document URL:

http://data.eol.ucar.edu/codiac/dss/id=106.ARCSS904