Superior National Forest Project/Campaign Document

Summary:

This project was an intensive remote sensing and field study of the boreal forest in the Superior National Forest (SNF). The purpose of this experiment was to investigate the ability of remote-sensing data to provide estimates of biophysical properties of ecosystems, such as leaf area index (LAI), biomass, and net primary productivity (NPP). The SNF is mostly covered by boreal forest. Boreal forests were chosen for this project because of their relative taxonomic simplicity, their great extent, and their potential sensitivity to climatic change. Information on the SNF project is available by accessing the SNF pages maintained by the ORNL DAAC at http://daac.ornl.govSNF/summary.html.

Table of Contents:

1. Project/Campaign Overview:

Name of Project/Campaign:

Superior National Forest (SNF)

Project/Campaign Introduction:

This project was an intensive remote sensing and field study of the boreal forest in the Superior National Forest (SNF). The purpose of this experiment was to investigate the ability of remote-sensing data to provide estimates of biophysical properties of ecosystems, such as leaf area index (LAI), biomass, and net primary productivity (NPP). The SNF is mostly covered by boreal forest. Boreal forests were chosen for this project because of their relative taxonomic simplicity, their great extent, and their potential sensitivity to climatic change. Information on the SNF project is available by accessing the SNF pages maintained by the ORNL DAAC at http://daac.ornl.gov/SNF/summary.html.

Project/Campaign Mission Objectives:

The purpose of this experiment was to investigate the ability of remote-sensing data to provide estimates of biophysical properties of ecosystems, such as leaf area index (LAI), biomass, and net primary productivity (NPP).

Discipline(s):

Leaf area index, biomass, net primary productivity, vegetation, optical properties, canopy reflectance.

Geographic Region(s):

Over 120 forest plots covering a 50 x 50 km area; near Ely, Minnesota, USA

Detailed Project/Campaign Description:

During the summers of 1983 and 1984, the National Aeronautics and Space Administration (NASA) conducted an intensive experiment in a portion of the Superior National Forest (SNF) near Ely, Minnesota, USA. The purpose of the experiment was to investigate the ability of remote sensing to provide estimates of biophysical properties of ecosystems, such as leaf area index (LAI), biomass and net primary productivity (NPP).

The study area covered a 50 x 50 km area centered at approximately 48 degrees North latitude and 92 degrees West longitude in northeastern Minnesota at the southern edge of the North American boreal forest. The SNF is mostly covered by boreal forest. Boreal forests were chosen for this project because of their relative taxonomic simplicity, their great extent, and their potential sensitivity to climatic change. Satellite, aircraft, helicopter and ground observations were obtained for the study area. These data comprise a unique dataset for the investigation of the relationships between the radiometric and biophysical properties of vegetated canopies. This is perhaps the most complete dataset of its type ever collected over a forested region.

Detailed vegetation data were collected on the ground for about 100 sampled sites. These sites represent a range of stand density and age for spruce and aspen and also include jackpine and mixed stands. At each site, five circular subplots of 16 meters in diameter were sampled within a large plot of 60 meters in diameter. Within the subplots, all woody stems over 2 meters in height were tallied by species, diameter, and height. Within each subplot, coverage by vegetation was determined for the canopy, subcanopy and understory. Thirty each of black spruce and aspen trees from outside the plots were sacrificed and dimension analysis relations developed between diameter at breast height, biomass and leaf area index. Also, above-ground NPP was estimated for each test site. For the aspen sites, bark area and understory leaf area indexes were found. During the spring, measurements of understory leaf extension and canopy coverage were made on several days to describe the phenology of an aspen stand.

Measurements of the optical properties of canopy componenets were made for wavelengths between 0.35 and 2.1 micrometers. Reflectance and transmittance properties of leaves and needles of eight major overstory tree species and three understory shrubs were measured. Multiple measurements of aspen and spruce allow an investigation of the variability of optical properties within a species, spagnum moss and leaf litter.

Above-canopy reflectance was observed by a helicopter-mounted Barnes Modular Multiband Radiometer (MMR). The helicopter MMR data have a spatial resolution of approximately 32 meters. In 1983, 10 days of data were collected between May and October, with a total of 105 sites observed. In 1984, 8 days of data were collected between May and September, with a total of 29 sites observed. Several sites have multiple observations, to allow studies of seasonal variation.

Thematic Mapper Simulator (TMS) data were collected fron the NASA C-130 flying over the SNF. The flights were in a "criss-cross" pattern to allow observation of the same location with multiple sun and view angles. The TMS scans out to 50 degrees off nadir; in flights at 5000 feet above ground level, a nadir pixel covers 3.81 meters along the scan. Three days of TMS data are presented; these data have been atmospherically corrected and calibrated to determine surface reflectance. A key goal of the experiment was to use the aircraft measurements to scale up to satellite observations for the remote sensing of biophysical parameters.

2. Data Availability:

Data Type(s):

Tabular data.

Input/Output Media:

Data available via SNF data sets list through the ORNL DAAC Web site. Formats available: FTP; on CD-ROM; diskette; 9-track magnetic, 150 MB 0.25 inch, or 8 mm tape.

Proprietary Status:

This data is free for public use.

3. Data Access:

Data Center Location:

The Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC) is housed within the Environmental Sciences Division of the Oak Ridge National Laboratory in Oak Ridge, Tennessee, USA.

Contact Information:

ORNL DAAC User Services Office
Oak Ridge National Laboratory
Phone: 865-241-3952
FAX: 865-574-4665
Email: ornldaac@ornl.gov

Associated Costs:

The data are are available free of charge.

4. Principal Investigator Information:

Dr. Forrest G. Hall
NASA Goddard Space Flight Center
Code 923
Greenbelt, Maryland
USA
Telephone +1 (301) 286-2974
Fax +1 (301) 286-0239
Email: fghall@ltpsun.gsfc.nasa.gov

5. Submitting Investigator Information:

Dr. Forrest G. Hall
NASA Goddard Space Flight Center
Code 923
Greenbelt, Maryland
USA
Telephone +1 (301) 286-2974
Fax +1 (301) 286-0239
Email: fghall@ltpsun.gsfc.nasa.gov

6. References:

On-line information is available from the following World Wide Web site: