This data set presents various climate data from sites in Barrow and Atqasuk, on the Northern Slope of Alaska. Parameters include thaw depth, air temperature, precipitation, wind speed, light intensity, plant canopy temperature, soil temperature, soil moisture, soil salinity, and relative humidity. Data were collected between June 1995 and August 2001 by various sensors connected to data loggers. Air and soil temperatures are given in degrees Celsius and wind speed is measured in meters per second. All other parameter measurements are detailed in the documentation. Data are available via FTP.
The research project was funded by the Arctic System Sciences (ARCSS) Program, grant number OPP 9714103.
Webber, P.J., Hollister, R.D. 2003. Climate Data from Barrow and Atqasuk Alaska 1995-2001. Boulder, CO: National Center for Atmospheric Research, ARCSS Data Archive.
| Category | Description |
|---|---|
| Data format | Text files |
| Spatial coverage and resolution | Atqasuk: 70.48 N - 157.42 W Barrow: 71.32 N - 156.62 W |
| Temporal coverage and resolution | 20 June 1995 to 25 August 2001 |
| File naming convention | Year started to year ended, area/data type, version For example: 1998-2001_Climate_v1.txt |
| File size | File sizes range from 88 KB to 42.6 MB |
| Parameter(s) | Hourly screen height temperature, precipitation, wind speed near the ground, light intensity, plant canopy temperature, soil temperature, soil moisture, soil salinity, and relative humidity. Daily and seasonal thaw depths. |
Patrick J. Webber, Professor
Department of Botany
Michigan State University
Robert D. Hollister
Doctoral Student
Department of Botany
Michigan State University
East Lansing, MI, USA
Tables in text format
File names consist of the following elements:
| Element | Example |
|---|---|
| Temporal Coverage | 1995-2001 |
| Area/Data Type | Climate Plot_Microclimate Detail_Microclimate Thaw |
| Version | v1 = version 1 |
Data file in this data set:
1998-2001_Climate_v1.txt
1995-2001_Plot_Microclimate.txt
1998-2001_Detail_Microclimate.txt
1995-2001_Thaw_v1.txt
The climate file provides data on air temperature, precipitation, wind speed, and light intensity. The Plot Microclimate file provides data on plant canopy air temperature and relative humidity. The Detail Microclimate file provides measurements of plant canopy air temperature, soil temperature, soil moisture, and soil salinity. The Thaw file provides data on thaw depths.
The four data files range from 88 KB to 42.6 MB
Southernmost Latitude: 70.48 N
Northernmost Latitude: 71.32 N
Westernmost Longitude: 157.42 W
Easternmost Longitude:156.62 W
Measurements were collected between 20 June 1995 to 25 August 2001
The following parameters were measured hourly:
air temperature (at screen height)
Precipitation
Wind speed near the ground
Light intensity
Plant canopy air temperature
Soil temperature
Soil moisture
Soil salinity
Relative humidity
Thaw depths were measured daily.
The following table describes each parameter and its source, range, and unit of measurement.
| Parameter | Source | Unit of Measurement |
|---|---|---|
| Air temperature | Model 107 Temperature Probe | degrees Celsius |
| Precipitation | TE525 Tipping Bucket Rain Gage at 25 cm height | millimeters |
| Wind speed | 03001 Wind Sentry at 13 cm height | meters per second |
| Light intensity | StowAway Light Intensity Logger | lumens per meter |
| Plant canopy air temperature | MRC Temperature Probe at canopy height 13 cm | degrees Celsius |
| Soil temperature | MRC Temperature Probe at ground surface to 45 cm below surface | degrees Celsius |
| Soil moisture | Vitel Hydra Probe at 7.5 cm below surface | water fraction by volume (wfv) |
| Soil salinity | Vitel Hydra Probe at 7.5 cm below surface | sodium chloride (NaCl)(grams) per unit volume (liter) |
| Relative humidity | StowAway Relative Humidity Logger at canopy height 13 cm | percentage |
| Thaw depths | Metal rod graduated by centimeters | centimeters |
Data are in tables. Each file is slightly different (described later in this section), so the number and types of columns vary across locations and may include the following column headings:
| SitCom |
The site (B=Barrow Alaska,A=Atqasuk Alaska) and community 1(D=Dry Heath Tundra,W=Wet Meadow Tundra) |
| Year | The year of the recording (1998-2001) |
| Julian | Julian day (1-366) |
| Month | Month of the year (1-12) |
| Hr | Hour of the day (0-23) |
| TempT | Air temperature (degree Celsius) at 1 meter height |
| Rain | Precipitation (mm) at 25 cm height |
| Wind | Wind speed (meters per second) at 13 cm height |
| LumSqm | Light (log of lumens per square meter) |
The following table describes the parameters for each file:
| File name | Sites | Dates | Parameters |
|---|---|---|---|
| 1998-2001_Climate_v1.txt | B=Barrow, A=Atqasuk, D=Dry Heath Tundra, W=Wet Meadow Tundra | 19 August 1998 to 25 August 2001 | screen height air temperature, precipitation, wind speed, and light intensity |
| 1995-2001_Plot_Microclimate.txt | B=Barrow, A=Atqasuk, D=Dry Heath Tundra, W=Wet Meadow Tundra, C=Control,E=Open-Top Chamber | 20 June 1995 to 16 August 2001 | plant canopy air temperature and relative humidity |
| 1998-2001_Detail_Microclimate.txt | B=Barrow, A=Atqasuk, D=Dry Heath Tundra, W=Wet Meadow Tundra, C=Control, E=Open-Top Chamber | 19 August 1998 to 25 August 2001 | plant canopy air temperature, soil temperature, soil moisture, and soil salinity |
| 1995-2001_Thaw_v1.txt | B=Barrow, A=Atqasuk, D=Dry Heath Tundra, W=Wet Meadow Tundra, C=Control, E=Open-Top Chamber | 21 June 1995 to 16 August 2001 | daily to seasonal thaw depths |
Missing data are indicated with -999.9
According to the investigators, these data are version 1 data and are very likely to contain errors. Specifically, air temperature and relative humidity were recorded between every 10 to 72 minutes and averaged by the hour. When no data were recorded within an hour (for recording intervals of greater than 1 hour) or if the data were considered erroneous, the average of the hour before and the hour after is recorded. Data collection was during the summer only and begun when the site was established (usually within a 2 days of snow melt) and ends around the middle of August.
Soil temperatures were taken every 10 to 18 minutes and averaged and recorded every hour. Salinity measurements were taken every hour.
Precipitation data are not valid for winter months and most likely underestimate true precipitation during the summer due to frequency of fine mists and strong winds.
Light intensity data are of poor quality due to potential reflectivity from condensation over the recording device.
The International Tundra Experiment, ITEX, was established in 1990 as a Man-And-the-Biosphere, Northern Sciences Network (MAB-NSN) initiative. Since then the program has grown rapidly and is today one of the most active international field programs in arctic ecology. The purpose of ITEX is to monitor the performance of plant species and communities on a circumpolar basis in undisturbed habitats with and without environmental manipulations. See http://www.systbot.gu.se/research/itex/itex.html for more information.
16 May 2003
http://data.eol.ucar.edu/codiac/dss/id=106.ARCSS908