This data set contains percent soil moisture ground measurements. These data were collected on the ground along the various flight lines flown in the Southern and Northern Study Areas (SSA and NSA) during 1994 by the gamma ray instrument. This data set contains information on the locations of field in-site measurements of soil moisture, depth of moss/humus layer, and water content of the moss/humus layer and contains information on soil conditions and vegetative cover around the sites.

Under-canopy precipitation measurements were made by the BOREAS HYD-01 science team in 1994, 1995, and 1996 at various flux tower sites in the NSA and SSA. In 1994, these data were collected at the NSA-OJP, NSA-YJP, SSA-OJP, and SSA-YJP sites. Starting in 1995 and ending in 1997, data were collected at the NSA-OBS, NSA-OJP, NSA-YJP, and SSA-OA. These data were collected to support HYD-01 research by measuring the amount of water that falls through the canopy and is intercepted by the ground or moss. These data coincide with volumetric soil moisture measurements made by HYD-01.

The BOREAS HYD-01 team made measurements of volumetric soil moisture at the SSA and NSA tower flux sites in 1994 and at selected tower flux sites in 1995-97. Different methods were used to collect these measurements, including neutron probe and manual and automated TDR. In 1994, the measurements were made every other day at the NSA-OJP, NSA-YJP, NSA-OBS, NSA-Fen, SSA-OJP, SSA-YJP, SSA-Fen, SSA-YA, and SSA-OBS sites. In 1995-97, when automated equipment was deployed at NSA-OJP, NSA-YJP, NSA-OBS, SSA-OBS, and SSA-OA, the measurements were made as often as every hour.

The BOREAS HYD-08 team made measurements of surface hydrological processes at the SSA-OBS Tower Flux site to support its research into point hydrological processes and the spatial variation of these processes. Data collected may be useful in characterizing canopy interception, drip, throughfall, moss interception, drainage, evaporation, and capacity during the growing season at daily temporal resolution. This particular data set contains the gross precipitation measurements for July to August 1996. Gross precipitation is the precipitation that falls that is not intercepted by tree canopies.

The BOREAS RSS-18 team collected ground-based sunphotometer data in support of AVIRIS remote sensing activities at the SSA. The following information was compiled by staff members of the BOReal Ecosystem-Atmosphere Study (BOREAS) Information System (BORIS) as part of their data documentation efforts.

The BOREAS Staff Science Aircraft Data Acquisition Program focused on providing the research teams with the remotely sensed aircraft data products they needed to compare and spatially extend point results. The MAS images, along with other remotely sensed data, were collected to provide spatially extensive information over the primary study areas. This information includes biophysical parameter maps such as surface reflectance and temperature. Collection of the MAS images occurred over the study areas during the 1994 field campaigns. The level-2 MAS data cover the dates of 21-Jul-1994, 24-Jul-1994, 04-Aug-1994 and 08-Aug-1994. The data are not geographically/geometrically corrected; however, files of relative X and Y coordinates for each image pixel were derived by using the C130 navigation data in a MAS scan model. The data are provided in binary image format files.

Airborne soil moisture measurement is based on the difference between natural terrestrial gamma radiation flux measured for comparatively wet and dry soils. The presence of moisture in the soil causes an effective increase in the soil density resulting in an increased attenuation of the gamma flux for relatively wet soil and a correspondingly lower flux at the ground surface. As part of the FIFE experiment, natural terrestrial gamma radiation data over a network of 24 flight lines were collected. The data acquisition procedure was designed to accumulate and store spectral radiation data along a flight line from which estimates of soil moisture could be computed. Ground-based soil moisture measurements were used to make a one-time calibration of the natural terrestrial radioisotope signal over the flight line network. A time-series of airborne soil moisture measurements (to a depth of 20 cm) was compared to an extensive, independent data set of ground-based soil moisture measurements. Estimates for flight line segments were found to have an average RMS error of approximately 2.5 % soil moisture (Peck et al., 1990).

The BOREAS HYD-08 team made measurements of surface hydrological processes that were collected at the SSA-OBS Tower Flux site in 1996 to support its research into point hydrological processes and the spatial variation of these processes. Data collected may be useful in characterizing canopy interception, drip, throughfall, moss interception, drainage, evaporation, and capacity during the growing season at daily temporal resolution. This particular data set contains the gravimetric moss moisture measurements from July to August 1996. To collect these data, a nested spatial sampling plan was implemented to support research into spatial variations of the measured hydrological processes and ultimately the impact of these variations on modeled carbon and water budgets.