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Burned and Unburned Field Site Data, Noatak, Seward, and North Slope, AK, 2016-2018

Documentation Revision Date: 2022-03-21

Dataset Version: 1

Summary

This dataset includes field measurements from unburned and burned 10 m x 10 m and 1 m x 1 m plots in the Noatak, Seward, and North Slope regions of the Alaskan tundra during July through August in the years 2016-2018. The data include vegetation coverage, soil moisture, soil temperature, soil thickness, thaw depth, and weather measurements. Measurements were recorded using ocular assessments and standard equipment. Plot photographs are included.

Potential field sites were determined a priori using a suite of fire indices and topographic variables. Burned and unburned areas were identified within fire perimeters recorded in the Alaska Large Fire Database (ALFD), and Landsat satellite imagery data was used to calculate indices of fire severity. The final set of sites were selected using a stratified random sampling scheme.

There are 7 data files included in this dataset; 1 file in comma-separated values (*.csv) format, 3 files in Keyhole Markup Language (*.kml) format, and 3 files in Portable Document Format (*.pdf).

Figure 1. Researchers at a field site in the Seward Peninsula during 2017.

Citation

Loboda, T.V., L.K. Jenkins, D. Chen, J. He, and A. Baer. 2022. Burned and Unburned Field Site Data, Noatak, Seward, and North Slope, AK, 2016-2018. ORNL DAAC, Oak Ridge, Tennessee, USA. https://doi.org/10.3334/ORNLDAAC/1919

Table of Contents

  1. Dataset Overview
  2. Data Characteristics
  3. Application and Derivation
  4. Quality Assessment
  5. Data Acquisition, Materials, and Methods
  6. Data Access
  7. References

Dataset Overview

This dataset includes field measurements from unburned and burned 10 m x 10 m and 1 m x 1 m plots in the Noatak, Seward, and North Slope regions of the Alaskan tundra during July through August in the years 2016–2018. The data include vegetation coverage, soil moisture, soil temperature, soil thickness, thaw depth, and weather measurements. Measurements were recorded using ocular assessments and standard equipment. Plot photographs are included.

Potential field sites were determined a priori using a suite of fire indices and topographic variables. Burned and unburned areas were identified within fire perimeters recorded in the Alaska Large Fire Database (ALFD), and Landsat satellite imagery data was used to calculate indices of fire severity. The final set of sites were selected using a stratified random sampling scheme. 

Project: Arctic-Boreal Vulnerability Experiment

The Arctic-Boreal Vulnerability Experiment (ABoVE) is a NASA Terrestrial Ecology Program field campaign being conducted in Alaska and western Canada, for 8 to 10 years, starting in 2015. Research for ABoVE links field-based, process-level studies with geospatial data products derived from airborne and satellite sensors, providing a foundation for improving the analysis, and modeling capabilities needed to understand and predict ecosystem responses to, and societal implications of, climate change in the Arctic and Boreal regions.

Related Publications

He, J., D. Chen, L. Jenkins, and T.V. Loboda. 2021. Impacts of wildfire and landscape factors on organic soil properties in Arctic tussock tundra. Environmental Research Letters 16:085004. https://doi.org/10.1088/1748-9326/ac1192

He, J., Loboda, T. V., Jenkins, L., Chen, D. 2019. Mapping fractional cover of major fuel type components across Alaskan tundra. Remote Sensing of Environment 232:111324. https://doi.org/10.1016/j.rse.2019.111324

Acknowledgment

This research was funded by the NASA Arctic-Boreal Vulnerability Experiment (ABoVE) program (grant NNX15AT79A).

Data Characteristics

Spatial Coverage: Noatak, Seward, and North Slope regions of the Alaskan tundra, U.S.

ABoVE Reference Locations

Domain: Core ABoVE

State/Territory: Alaska

Grid cells: Ch036v010, Ch038v011, Ch038v012, Ch037v011, Ch036v009, Ch035v009, Ch036v011, Ch025v011, Ch024v011, Ch050v019, Ch051v019, Ch052v018, Ch050v020

Spatial Resolution: Point measurements at 10 x 10- m and 1 x 1 m plots

Temporal Coverage: 2016-07-22 to 2018-08-27

Temporal Resolution: One and two-time estimates

Study Area: All latitude and longitude are given in decimal degrees. These coordinates are the approximate locations of the study sites and may not match the extent of the data files.

Site Northern Extent Southern Extent Eastern Extent Western Extent
Noatak, Seward, North Slope regions, Alaska 69.663 65.018 -148.640 -164.929

Data File Information

There are 7 data files included in this dataset; 1 file in comma-separated values (*.csv) format, 3 files in Keyhole Markup Language (*.kml) format, and 3 files in Portable Document Format (*.pdf).

Table 1. File names and descriptions.

File Name Description
Plot_Data_Noatak_Seward_Alaska.csv Provides vegetation percent coverage, environmental conditions, weather descriptions, wind, and temperature data, as well as soil temperature, thaw depth, and soil moisture measurements (Table 1). Missing numeric data are represented by "-9999", and missing text values are represented by "NA".
YYYY_field_photos.kml Georeferenced photographs of the study sites for each of the years 2016, 2017, and 2018. In the names of these files, YYYY is either 2016, 2017, or 2018.
YYYY_field_photos.pdf Images and metadata for each study site. In the names of these files, YYYY is either 2016, 2017, or 2018. Within the files, information can be matched to data provided in the file  Plot_Data_Noatak_Seward_Alaska.csv (for fields photo_north, photo_south, photo_east, photo_west, photo_nadir, and photo_other) by the name IMGP0aaa.JPG, where aaa is the ID number.

Data File Details

Table 2. Variable names and descriptions in the file Plot_Data_Noatak_Seward_Alaska.csv.

Variable Units Description
site_name text Field site ID for 10 m x 10 m plots and transect locations
site_type text Burned or unburned types as recorded by the Alaskan Large Fire Database
geographic_region text NOAT: Noatak River Valley; SEWP: Seward Peninsula; NS: North Slope
fire_frequency text Fire frequency based on fire perimeters and verified, where possible, with satellite imagery. Burned sites have a value of ≥ and unburned sites have a value 0.
fire1_year YYYY The most recent year of fire occurrence
fire1_bsi text Burn Severity Index (bsi) for the most recent year of fire occurrence, values include: 1 (very low), 2 (moderate), 3 (high), 4 (severe)
fire2_year YYYY The second most recent year of fire occurrence
fire2_bsi text Burn Severity Index (bsi) for the second most recent year of fire occurrence, values include: 1 (very low), 2 (moderate), 3 (high), 4 (severe)
fire3_year YYYY The third most recent year of fire occurrence
fire3_bsi text Burn Severity Index (bsi) for the third most recent year of fire occurrence, values include: 1 (very low), 2 (moderate), 3 (high), 4 (severe)
fire4_year YYYY The fourth most recent year of fire occurrence
fire4_bsi text Burn Severity Index (bsi) for the fourth most recent year of fire occurrence, values include: 1 (very low), 2 (moderate), 3 (high), 4 (severe)
measurement_year YYYY Data collection year
measurement_date YYYY-MM-DD Data collection date
measurement_hour HH Data collection hour (local time)
measurement_time HH:MM:SS Data collection time (local time)
latitude Decimal degrees Latitude of the southeast (SE) corner of the site (10 x 10-m plot)
longitude Decimal degrees Longitude of the SE corner of the site (10 x 10-m plot)
site_description text General description of the 10 m x 10 m site (e.g. vegetation distribution, drainage, topography, etc.)
weather_current text Description of weather conditions during data collection
weather_past_12hr text Description of weather conditions during the past 12 hours before data collection
rain text Binary data representing the occurrence of rain: 1 (yes) or 0 (no)
drainage text Drainage types, values include: 1 (flat-poorly drained), 2 (flat-drained), 3 (moderately-drained), 4 (well-drained). The values were created through a combination of elevation, slope, flow accumulation, and ideas described in (Kasischke and Hoy, 2012).
air_temp degrees C Air temperature at 2 m above the surface for 1 m x 1m plots and transect points
rh % Relative humidity at 2 m above the surface for 1 m x 1m plots and transect points
dew_temp degrees C Dew point temperature at 2 m above the surface for 1 m x 1m plots and transect points
wind_speed m/s Wind speed for 1 m x 1m plots and transect points
wind_direction Degree Wind direction (360 degrees with 0 at N) for 1 m x 1m plots and transect points
moss_percent_cover % Percent cover of moss within the 10 m x 10 m plot estimated via ocular assessment
moss_cover_flag   Flag column to indicate where moss cover percentage is <1 or other text note
moss_distribution text General description of the spatial distribution of moss within the 10 m x 10 m plot
lichen_percent_cover % Percent cover of lichen within the 10 m x 10 m plot estimated via ocular assessment
lichen_cover_flag   Flag column to indicate where lichen cover percentage is <1 or other text note
lichen_distribition text General description of the spatial distribution of lichen within the 10 m x 10 m plot
grass_percent_cover % Percent cover of grass within the 10 m x 10 m plot estimated via ocular assessment
grass_distribution text General description of the spatial distribution of grass within the 10 m x 10 m plot
sedge_percent_cover % Percent cover of sedge within the 10 m x 10 m plot estimated via ocular assessment
sedge_cover_flag   Flag column to indicate where sedge cover percentage is <1 or other text note
sedge_distribution text General description of the spatial distribution of sedge within the 10 m x 10 m plot
shrub_percent_cover % Percent cover of shrub within the 10 m x 10 m plot estimated via ocular assessment
shrub_height cm Mean height of shrubs at the 10 m x 10 m plot
shrub_distribution text General description of the spatial distribution of shrub within the 10 m x 10 m plot
char_percent_cover % Percent cover of char within the 10 m x 10 m plot estimated via ocular assessment
char_cover_flag   Flag column to indicate where char cover percentage is <1 or other text note
char_distribution text General description of the spatial distribution of char within the 10 m x 10 m plot
other_ground_cover_type text A different ground cover type other than measured, if any
other_ground_cover_percent_cover % Percent cover of the type, if any
other_cover_flag   Flag column to indicate where other cover percentage is <1 or other text note
other_ground_cover_height cm Height of the species of the type, if any
other_distribution text Spatial distribution of the type, if any
other2_ground_cover_type text A second ground cover type other than measured, if any
other2_ground_cover_percent_cover % Percent cover of the second type, if any
other2_cover_flag   Flag column to indicate where other cover2 percentage is <1 or other text note
other2_distribution text Spatial distribution of the second type, if any
tussock_center_uncompacted_length cm Uncompacted length of the central tussock located at the southeast (SE) corner of the 10 m x 10 m plot
tussock_center_compacted_length cm Compacted length of the central tussock located at the SE corner of the 10 m x 10 m plot
tussock_center_uncompacted_width cm Uncompacted width of the central tussock located at the SE corner of the 10 m x 10 m plot
tussock_center_compacted_width cm Compacted width of the central tussock located at the SE corner of the 10 m x 10 m plot
tussock_center_uncompacted_area2 cm2 Uncompacted area of the central tussock located at the SE corner of the 10 m x 10 m plot
tussock_center_compacted_area2 cm2 Compacted area of the central tussock located at the SE corner of the 10 m x 10 m plot
tussock_center_depth cm Depth (or height) of the central tussock located at the SE corner of the 10 m x 10 m plot
tussock_a_distance_from_center cm Distance from tussock A to the central tussock within 1 m x 1 m plots
tussock_a_uncompacted_length cm Uncompacted length of tussock A within 1 m x 1 m plots
tussock_a_compacted_length cm Compacted length of tussock A within 1 m x 1 m plots
tussock_a_uncompacted_width cm Uncompacted width of tussock A within 1 m x 1 m plots
tussock_a_compacted_width cm Compacted width of tussock A within 1 m x 1 m plots
tussock_a_uncompacted_area2 cm2 Uncompacted area of tussock A within 1 m x 1 m plots
tussock_a_compacted_area2 cm2 Compacted area of tussock A within 1 m x 1 m plots
tussock_a_depth cm Depth (height) of tussock A within 1 m x 1 m plots
tussock_b_distance_from_center cm Distance from tussock B to the central tussock within 1 m x 1 m plots
tussock_b_uncompacted_length cm Uncompacted length of tussock B within 1 m x 1 m plots
tussock_b_compacted_length cm Compacted length of tussock B within 1 m x 1 m plots
tussock_b_uncompacted_width cm Uncompacted width of tussock B within 1 m x 1 m plots
tussock_b_compacted_width cm Compacted width of tussock B within 1 m x 1 m plots
tussock_b_uncompacted_area2 cm2 Uncompacted area of tussock B within 1 m x 1 m plots
tussock_b_compacted_area2 cm2 Compacted area of tussock B within 1 m x 1 m plots
tussock_b_depth cm Depth (height) of tussock B within 1 m x 1 m plots
tussock_c_distance_from_center cm Distance from tussock C to the central tussock within 1 m x 1 m plots
tussock_c_uncompacted_length cm Uncompacted length of tussock C within 1 m x 1 m plots
tussock_c_compacted_length cm Compacted length of tussock C within 1 m x 1 m plots
tussock_c_uncompacted_width cm Uncompacted width of tussock C within 1 m x 1 m plots
tussock_c_compacted_width cm Compacted width of tussock C within 1 m x 1 m plots
tussock_c_uncompacted_area2 cm2 Uncompacted area of tussock C within 1 m x 1 m plots
tussock_c_compacted_area2 cm2 Compacted area of tussock C within 1 m x 1 m plots
tussock_c_depth cm Depth (height) of tussock C within 1 m x 1 m plots
percent_cover_shrubs % Percent cover of shrubs in the 1 m x 1 m plot at the SE corner of the 10 m x 10 m plot
ave_height_shrub cm Averaged height of shrubs in the 1 m x 1 m plot at the SE corner of the 10 m x 10 m plot
stem_count_shrub text Stem count of shrubs in the 1 m x 1 m plot at the SE corner of the 10 m x 10 m plot
depth_to_mineral_soil_1 cm Soil pit: measurement of depth to mineral soil side 1
depth_to_mineral_soil_2 cm Soil pit: measurement of depth to mineral soil side 2
depth_to_mineral_soil_3 cm Soil pit: measurement of depth to mineral soil side 3
depth_to_mineral_soil_4 cm Soil pit: measurement of depth to mineral soil side 4
ave_depth_to_mineral_soil cm Soil pit: averaged depth to mineral soil depth
soil_sampled text Soil sample has been collected at the plot for lab measurements: yes or no
thaw_depth_1 cm The first measurement of thaw depth for 1 m x 1 m plots and transect points
thaw_depth_2 cm The second measurement of thaw depth for 1 m x 1 m plots and transect points
thaw_depth_3 cm The third measurement of thaw depth for 1 m x 1 m plots and transect points
thaw_depth_4 cm The fourth measurement of thaw depth for 1 m x 1 m plots and transect points
thaw_depth_5 cm The fifth measurement of thaw depth for 1 m x 1 m plots and transect points
thaw_depth_6 cm The sixth measurement of thaw depth for 1 m x 1 m plots and transect points
active_layer_depth_avg cm Averaged active layer thickness for 1 m x 1 m plots and transect points
soil_temp_1 degrees C The first measurement of soil temperature for 1 m x 1 m plots and transect points
soil_temp_2 degrees C The second measurement of soil temperature for 1 m x 1 m plots and transect points
soil_temp_3 degrees C The third measurement of soil temperature for 1 m x 1 m plots and transect points
soil_temp_av degrees C Averaged soil temperature for 1 m x 1 m plots and transect points
soil_substrate_1 text Soil substrate of the first soil temperature measurement, values include: BM (Burned moss), DM (Dead moss), FB (Frost Boil), G (Grass), L (Lichen), M (Moss), MS (Mineral soil), OS (Organic soil), S (Shrub), W (Wetland)
soil_substrate_2 text Soil substrate of the second soil temperature measurement values include: BM (Burned moss), DM (Dead moss), FB (Frost Boil), G (Grass), L (Lichen), M (Moss), MS (Mineral soil), OS (Organic soil), S (Shrub), W (Wetland)
soil_substrate_3 text Soil substrate of the third soil temperature measurement values include: BM (Burned moss), DM (Dead moss), FB (Frost Boil), G (Grass), L (Lichen), M (Moss), MS (Mineral soil), OS (Organic soil), S (Shrub), W (Wetland)
notes_alt text Additional information of active layer thickness measurements for 1 m x 1 m plots and transect points
notes_site text Additional information about the 1 m x 1 m plots and transect points
per_vmc_6cm_oldprobe_1 % The first % VMC measurement at 6 cm depth using old probe
probe_period_6cm_oldprobe_1 text Probe period of the first % VMC measurement at 6 cm depth using old probe
per_vmc_6cm_oldprobe_2 % The second % VMC measurement at 6 cm depth using old probe
probe_period_6cm_oldprobe_2 text Probe period of the second % VMC measurement at 6 cm depth using old probe
per_vmc_6cm_oldprobe_3 % The third % VMC measurement at 6 cm depth using old probe
probe_period_6cm_oldprobe_3 text Probe period of the third % VMC measurement at 6 cm depth using old probe
per_vmc_6cm_oldprobe_4 % The fourth % VMC measurement at 6 cm depth using old probe
probe_period_6cm_oldprobe_4 text Probe period of the fourth % VMC measurement at 6 cm depth using old probe
per_vmc_6cm_oldprobe_5 % The fifth % VMC measurement at 6 cm depth using old probe
probe_period_6cm_oldprobe_5 text Probe period of the fifth % VMC measurement at 6 cm depth using old probe
per_vmc_av_6cm_old % Averaged % VMC measurement at 6 cm depth using old probe
probe_period_av_6cm_old text Averaged probe period at 6 cm depth using old probe
per_vmc_calibrated_6cm_old % Calibrated % VMC measurement at 6 cm depth using old probe
per_vmc_12cm_oldprobe_1 % The first % VMC measurement at 12 cm depth using old probe
probe_period_12cm_oldprobe_1 text Probe period of the first % VMC measurement at 12 cm depth using old probe
per_vmc_12cm_oldprobe_2 % The second % VMC measurement at 12 cm depth using old probe
probe_period_12cm_oldprobe_2 text Probe period of the second % VMC measurement at 12 cm depth using old probe
per_vmc_12cm_oldprobe_3 % The third % VMC measurement at 12 cm depth using old probe
probe_period_12cm_oldprobe_3 text Probe period of the third % VMC measurement at 12 cm depth using old probe
per_vmc_12cm_oldprobe_4 % The fourth % VMC measurement at 12 cm depth using old probe
probe_period_12cm_oldprobe_4 text Probe period of the fourth % VMC measurement at 12 cm depth using old probe
per_vmc_12cm_oldprobe_5 % The fifth % VMC measurement at 6 cm depth using old probe
probe_period_12cm_oldprobe_5 text Probe period of the fifth % VMC measurement at 6 cm depth using old probe
per_vmc_av_12cm_old % Averaged % VMC measurement at 12 cm depth using old probe
probe_period_av_12cm_old text Averaged probe period at 12 cm depth using old probe
per_vmc_calibrated_12cm_old % Calibrated % VMC measurement at 12 cm depth using old probe
per_vmc_6cm_newprobe_1 % The first % VMC measurement at 6 cm depth using new probe
probe_period_6cm_newprobe_1 text Probe period of the first % VMC measurement at 6 cm depth using new probe
per_vmc_6cm_newprobe_2 % The second % VMC measurement at 6 cm depth using new probe
probe_period_6cm_newprobe_2 text Probe period of the second % VMC measurement at 6 cm depth using new probe
per_vmc_6cm_newprobe_3 % The third % VMC measurement at 6 cm depth using new probe
probe_period_6cm_newprobe_3 text Probe period of the third % VMC measurement at 6 cm depth using new probe
per_vmc_6cm_newprobe_4 % The fourth % VMC measurement at 6 cm depth using new probe
probe_period_6cm_newprobe_4 text Probe period of the fourth % VMC measurement at 6 cm depth using new probe
per_vmc_6cm_newprobe_5 % The fifth % VMC measurement at 6 cm depth using new probe
probe_period_6cm_newprobe_5 text Probe period of the fifth % VMC measurement at 6 cm depth using new probe
per_vmc_av_6cm_new % Averaged % VMC measurement at 6 cm depth using new probe
probe_period_av_6cm_new text Averaged probe period at 6 cm depth using new probe
per_vmc_calibrated_6cm_new % Calibrated % VMC measurement at 6 cm depth using new probe
per_vmc_12cm_newprobe_1 % The first % VMC measurement at 12 cm depth using new probe
probe_period_12cm_newprobe_1 text Probe period of the first % VMC measurement at 12 cm depth using new probe
per_vmc_12cm_newprobe_2 % The second % VMC measurement at 12 cm depth using new probe
probe_period_12cm_newprobe_2 text Probe period of the second % VMC measurement at 12 cm depth using new probe
per_vmc_12cm_newprobe_3 % The third % VMC measurement at 12 cm depth using new probe
probe_period_12cm_newprobe_3 text Probe period of the third % VMC measurement at 12 cm depth using new probe
per_vmc_12cm_newprobe_4 % The fourth % VMC measurement at 12 cm depth using new probe
probe_period_12cm_newprobe_4 text Probe period of the fourth % VMC measurement at 12 cm depth using new probe
per_vmc_12cm_newprobe_5 % The fifth % VMC measurement at 12 cm depth using new probe
probe_period_12cm_newprobe_5 text Probe period of the fifth % VMC measurement at 12 cm depth using new probe
per_vmc_av_12cm_new % Averaged % VMC measurement at 12 cm depth using new probe
probe_period_av_12cm_new text Averaged probe period at 12 cm depth using new probe
per_vmc_calibrated_12cm_new % Calibrated % VMC measurement at 12 cm depth using new probe
per_vmc_20cm_newprobe_1 % The first % VMC measurement at 20 cm depth using new probe
probe_period_20cm_newprobe_1 text Probe period of the first % VMC measurement at 12 cm depth using new probe
per_vmc_20cm_newprobe_2 % The second % VMC measurement at 12 cm depth using new probe
probe_period_20cm_newprobe_2 text Probe period of the second % VMC measurement at 12 cm depth using new probe
per_vmc_20cm_newprobe_3 % The third % VMC measurement at 12 cm depth using new probe
probe_period_20cm_newprobe_3 text Probe period of the third % VMC measurement at 12 cm depth using new probe
per_vmc_20cm_newprobe_4 % The fourth % VMC measurement at 12 cm depth using new probe
probe_period_20cm_newprobe_4 text Probe period of the fourth % VMC measurement at 12 cm depth using new probe
per_vmc_20cm_newprobe_5 % The fifth % VMC measurement at 12 cm depth using new probe
probe_period_20cm_newprobe_5 text Probe period of the fifth % VMC measurement at 12 cm depth using new probe
per_vmc_av_20cm_new % Averaged % VMC measurement at 20 cm depth using new probe
probe_period_av_20cm_new text Averaged probe period at 20 cm depth using new probe
per_vmc_calibrated_20cm_new % Calibrated % VMC measurement at 20 cm depth using new probe
notes_soilmoisture text Additional information of soil moisture measurements
photo_north text ID of the photo taken towards the north of the 10 m x 10 m plot
photo_south text ID of the photo taken towards the south of the 10 m x 10 m plot
photo_east text ID of the photo taken towards the east of the 10 m x 10 m plot
photo_west text ID of the photo taken towards the west of the 10 m x 10 m plot
photo_nadir text ID of the photo taken at nadir of the 10 m x 10 m plot
photo_other text IDs of other photos related to the 10 m x 10 m plot
photo_other_desc text Description of "Photo_Other"

Application and Derivation

The Alaskan tundra experiences a large number of small fires with shorter return intervals. This study examined the impact of single and repeated fires on vegetation and soil properties compared to unburned areas. The data can be used in studies focused on soil ecosystem functioning, permafrost, and climate change.

Quality Assessment

Dual blind entries for data were implemented to identify and correct errors from the process of transcribing field datasheets.

Data Acquisition, Materials, and Methods

Study Sites

The data were collected during three field campaigns at sites with active fire activity located in the Noatak River Valley, Seward Peninsula, and North Slope regions in Alaska. The field campaigns were conducted from July to August in the years 2016, 2017, and 2018.

site locations

Figure 2. Location of field sites in Alaska, U.S.

Fire Variables

The potential field sites were determined a priori using a suite of fire indices and topographic variables. Burned and unburned areas were identified within fire perimeters recorded in the Alaska Large Fire Database (ALFD; available at https://blm-egis.maps.arcgis.com/apps/MapSeries/index.html?appid=32ec4f34fb234ce58df6b1222a207ef1). Plots were established at random points at locations of 24 individual fires spanning the 1971–2015 fire seasons and covered combinations of fire properties and drainage categories.

Landsat satellite imagery data (available at https://earthexplorer.usgs.gov/) were used to calculate the indices of fire severity. Using one clear image taken during the next growing season after an identified fire, two fire indices were used to identify burned areas and classify burn severity. For fires pre-1982, Tasseled-Cap Greenness (Kauth and Thomas, 1976) was used to identify burned and unburned areas. For fires post-1982, the Normalized Burn Ratio following methods described in Loboda et al. (2013) was used.

The Burn Severity Index was assigned using the tundra-specific methodology (Loboda et al., 2013). Fire frequency and years since the last burn was calculated for both burned and unburned areas using the ALFD and Landsat imagery (He et al., 2021).

Topographic Variables

Four categories were developed for drainage types as in Kasischke and Hoy (2012); elevation, and slope and flow accumulation (calculated using a digital elevation model (Carswell, 2013).

  1. flat, poorly drained (slope<2 degrees & flow accumulation>0)
  2. flat, drained (slope<2 degrees & flow accumulation=0)
  3. moderately drained (slope≥2 degrees & flow accumulation>0)
  4. well-drained (slope≥2 degrees & flow accumulation=0)

Sampling

The final set of sites was selected using a stratified random sampling scheme, with purposeful oversampling due to anticipated limiting factors the field team may experience once on the ground such as time and physical accessibility. A total of 197 sites were visited (159 burned, 33 unburned) and sampled by establishing a 10 m x 10 m plot. Each plot included a smaller 1 m x 1 m plot in the southeast corner of the site or within 2 m diameter of the transect points. Tussock measurements include the closest tussocks to the SE corner. Soil temperature, soil volumetric moisture content, air temperature, and relative humidity were measured at these 1 m2 small plots while vegetation characteristics were measured across the 100 m2 plot. In addition, 632 point locations were sampled along transects in the vicinity of the plots (Fig. 3) where soil temperature, air temperature, and active layer thickness were measured.

Illustration of field plots and transect sampling.

Figure 3. Representative layout of 10 m x 10 m field plots and points sampled along a transect in the same vicinity.

Field measurements included active layer depth, soil temperature, and weather. Different measurements were conducted in plots versus transect points. Soil temperature measurements were recorded using a Hanna digital soil thermometer. Soil moisture was measured using a Campbell Scientific Hydrosense II probe. Soil moisture estimates (%VMC) were calibrated using the equation:

% VWC = A*(Probe Period)2 + B*(Probe Period) + C

Calibration equations were developed (in a laboratory setting) using a total of 22 samples taken during the field campaigns (Jenkins, 2019). Weather data were recorded using Ambient Weather WM-4 digital stations.

Refer to He et al. (2021) for additional information.

Data Access

These data are available through the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).

Burned and Unburned Field Site Data, Noatak, Seward, and North Slope, AK, 2016-2018

Contact for Data Center Access Information:

References

Carswell Jr., W.J. 2013. The 3D Elevation Program: summary for Alaska, Fact Sheet. Reston, VA. https://doi.org/10.3133/fs20133083

He, J., D. Chen, L. Jenkins, and T.V. Loboda. 2021. Impacts of wildfire and landscape factors on organic soil properties in Arctic tussock tundra. Environmental Research Letters 16:085004. https://doi.org/10.1088/1748-9326/ac1192

Jenkins, L. 2019. Multi-Scale Detection and Characterization of Physical and Ecological Change in the Arctic Using Satellite Remote Sensing, Chapter 4: Determination of Synthetic Aperture Radar Backscatter in the Tundra as a Function of Fire and Biophysical Parameters. Doctoral Dissertation. University of Michigan. http://hdl.handle.net/2027.42/151574

Kasischke, E.S., and E.E. Hoy. 2012. Controls on carbon consumption during Alaskan wildland fires. Global Change Biology 18:685-699. https://doi.org/10.1111/j.1365-2486.2011.02573.x

Kauth, R. J., and G.S. Thomas. 1976. The tasselled cap--a graphic description of the spectral-temporal development of agricultural crops as seen by Landsat. LARS Symposia Paper 159. https://docs.lib.purdue.edu/lars_symp/159

Loboda, T.V., N.H. French, C. Hight-Harf, L. Jenkins, and M.E. Miller. 2013. Mapping fire extent and burn severity in Alaskan tussock tundra: An analysis of the spectral response of tundra vegetation to wildland fire. Remote Sensing of Environment 134:194-209. https://doi.org/10.1016/j.rse.2013.03.003