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  • Knowledge of the optical properties of the components of the forest canopy is important to the understanding of how plants interact with their environment and how this information may be used to determine vegetation characteristics using remote sensing. During the summers of 1983 and 1984, samples of the major components of the boreal forest canopy (needles, leaves, branches, moss, litter) were collected in the Superior National Forest (SNF) of Minnesota and sent to the Johnson Space Center (JSC). At JSC, the spectral reflectance and transmittance characteristics of the samples were determined for wavelengths between .35 and 2.1 micrometers using the Cary-14 radiometer. This report presents plots of these data as well as averages to the Thematic Mapper Simulator (TMS) bands. There were two main thrusts to the SNF optical properties study. The first was to collect the optical properties of many of the components of the boreal forest canopy. The second goal of the study was to investigate the variability of optical properties within a species. The results of these studies allow a comparison of the optical properties of a variety of different species and a measure of the variability within species. These data provide basic information necessary to model canopy reflectance patterns. [ This document was provided by NASA's Global Change Master Directory. For more information on the source of this metadata please visit http://gcmd.nasa.gov/r/geoss/[GCMD]SNF_LEAFCARY ]

  • The BOREAS TE-06 team collected several data sets in support of its efforts to characterize and interpret information on the plant biomass, allometry, biometry, sapwood, leaf area index, net primary production, soil temperature, leaf water potential, soil CO2 flux, and multivegetation imagery of boreal vegetation. This data set contains measurements of estimates of the standing biomass and leaf area index for the plant species at the TF, CEV, and AUX sites in the SSA and NSA during the growing seasons of 1994 and 1995. [ This document was provided by NASA's Global Change Master Directory. For more information on the source of this metadata please visit http://gcmd.nasa.gov/r/geoss/[GCMD]BOREAS_TE6BMFLG ]

  • The BOREAS TE-10 team collected several data sets in support of its efforts to characterize and interpret information on the reflectance, transmittance, gas exchange, oxygen evolution, and biochemical properties of boreal vegetation. This data set describes the spectral optical properties (reflectance and transmittance) of boreal forest conifers and broadleaf tree leaves as measured with a Spectron Engineering SE590 spectroradiometer at the SSA OBS, OJP, YJP, OA, OA-AUX, YA-AUX, and YA sites. The data were collected during the growing seasons of 1994 and 1996. [ This document was provided by NASA's Global Change Master Directory. For more information on the source of this metadata please visit http://gcmd.nasa.gov/r/geoss/[GCMD]BOREAS_TE10LOPT ]

  • Data from the LAI-2000 instrument were processed to determine the leaf area index (LAI) at the EOS Validation Core Site in Kataba Local Forest, approximately 20 km south of Mongu, Zambia. Measurements began in 2000 and continued into 2002, with measurements collected about every month throughout the growing season to examine the phenology of LAI for the site. The LAI-2000 measures the intensity of blue light in five upward-looking concentric conical rings. Measurements are made under the forest canopy and compared with open-sky measurements to determine transmittance for each of the five viewing angles. The sensor head was placed at ground level while the sensors measured light levels in conical scans. Effective leaf area was calculated from the transmittance in the different view angles based on the assumption of a random distribution of leaves (Welles and Norman, 1991).The LAI-2000 was carried along three parallel transects, each 750 m long and spaced 250 m apart. Each transect was divided into 25 m segments, and measurements were collected at the endpoints of each segment. Data from all transects were combined to provide site-average LAI for each sampling date. The length and spacing of the transects were chosen to sample an area large enough to be representative of a 1 km MODIS pixel. Ground observations of LAI from this study compared with MODIS LAI products were found to be in close agreement.The data are stored in an ASCII text file, in comma-separated-value (csv) format, with column headers. [ This document was provided by NASA's Global Change Master Directory. For more information on the source of this metadata please visit http://gcmd.nasa.gov/r/geoss/[GCMD]s2k_lai-2000 ]

  • This data set was processed by BORIS staff from the original vector data of species, crown closure, cutting class, and site classification/subtype into raster files. The original polygon data were received from Linnet Graphics, the distributor of data for MNR. In the case of the species layer, the percentages of species composition were removed. This reduced the amount of information contained in the species layer of the gridded product, but it was necessary in order to make the gridded product easier to use. The original maps were produced from 1:15,840-scale aerial photography collected in 1988. [ This document was provided by NASA's Global Change Master Directory. For more information on the source of this metadata please visit http://gcmd.nasa.gov/r/geoss/[GCMD]BOREAS_NSAFCOVR ]

  • The BOREAS TF-11 team gathered a variety of data to complement their tower flux measurements collected at the SSA Fen site. These data are LAI measurements made by the TF-11 team throughout the 1995 growing season. The data include the LAI of plants that fall into six categories: total, Carex spp., Betula pumila, Menyanthes trifoliata, Salix spp., and other vascular plants. [ This document was provided by NASA's Global Change Master Directory. For more information on the source of this metadata please visit http://gcmd.nasa.gov/r/geoss/[GCMD]BOREAS_TF11LAI ]

  • The BOREAS TE-10 team collected several data sets in support of its efforts to characterize and interpret information on the reflectance, transmittance, gas exchange, chlorophyll content, carbon content, hydrogen content, and nitrogen content of boreal vegetation. This data set contains measurements of assimilation, stomatal conductance, transpiration, internal CO2 concentration, and water use efficiency conducted in the SSA during the growing seasons of 1994 and 1996 using a portable gas exchange system. [ This document was provided by NASA's Global Change Master Directory. For more information on the source of this metadata please visit http://gcmd.nasa.gov/r/geoss/[GCMD]BOREAS_TE10LGXD ]

  • The Vegetation-Ecosystem Modeling and Analysis Project (VEMAP) was a large, collaborative, multi-institutional, international effort whose goal was to evaluate the sensitivity of terrestrial ecosystem and vegetation processes to altered climate forcing and elevated atmospheric CO2. Phase 1 of the VEMAP project developed historical (1895-1993) data sets of observed climate, soils, and vegetation compatible with the requirements of ecosystem models and vegetation distribution models. See the VEMAP Phase 1 User's Guide for more information. Phase 2 developed historical (1895-1993) gridded data sets of climate (temperature, precipitation, solar radiation, humidity, and wind speed) and projected (1994-2100) gridded annual and monthly climate data sets using output from two climate system models (CCCma (Canadian Centre for Climate Modeling and Analysis) and Hadley Centre models). See the VEMAP Phase 2 User's Guide for additional background information.Two Phase 2 model experiments were run. First, a set of selected biogeochemical models and coupled biogeochemical-biogeographical models were run from 1895 to 1993 to compare model responses to the historical time series and current ecosystem biogeochemistry. Second, these same models were run on the projected 1994 to 2100 data to compare their ecological responses to transient scenarios of climate and atmospheric CO2 change. Model runs were performed for daily, monthly, and annual gridded data sets. The output of the annual model runs in VEMAP grid format are contained in this data set.The models investigated included five biogeochemical cycling models, which simulate plant production and nutrient cycles, but rely on a static land-cover type, and two dynamic global vegetation models (DGVMs) that combine biogeochemical cycling processes with dynamic biogeographical processes including succession and fire simulation.Biogeochemical Cycling ModelsBiome-BGC (BioGeochemical Cycles)CenturyCentury rxveg GTEC (Global Terrestrial Ecosystem Carbon Model)TEM (Terrestrial Ecosystem Model)Dynamic Global Vegetation ModelsLPJ (Lund-Potsdam-Jena MC1 (MC 5 modified Century)VEMAP 2 model intercomparison results have been published by Schimel et al.(2000), Bachelet et al. (2003) and Gordon and Famiglietti (2004). Related Data SetsAvailable on-line [http://www.daac.ornl.gov] from Oak Ridge National Laboratory Distributed Active Archive CenterVEMAP 2: U.S. ANNUAL CLIMATE, 1895-1993 VEMAP 2: U.S. MONTHLY CLIMATE, 1895-1993, VERSION 2 VEMAP 2: U.S. DAILY CLIMATE, 1895-1993 VEMAP 2: U.S. ANNUAL CLIMATE CHANGE SCENARIOS VEMAP 2: U.S. MONTHLY CLIMATE CHANGE SCENARIOS, VERSION 2 VEMAP 2: U.S. DAILY CLIMATE CHANGE SCENARIOS VEMAP 2: Annual Ecosystem Model Responses to U.S. Climate Change, 1994-2100 [ This document was provided by NASA's Global Change Master Directory. For more information on the source of this metadata please visit http://gcmd.nasa.gov/r/geoss/[GCMD]vemap2-annual_rslts ]

  • The Fifteen Minute Stream Flow Data from the USGS Data Set contains 15 minute stream flow data from the USGS station located 2.9 miles upstream from the mouth of Kings Creek. The record extends from April 1, 1979 through September 2, 1988. The purpose of this data set was to provide accurate measurements of the stream flow from Kings Creek so that a water budget analysis for the northwest quadrant of the FIFE study area could be performed. The stilling pipe installed at the USGS station operates on the principle that the water level in a standpipe at a specific location within a stream bed can be converted to a volume of water in the stream bed. The tracking of the change in stream height with time then enables the calculation of stream flow. [ This document was provided by NASA's Global Change Master Directory. For more information on the source of this metadata please visit http://gcmd.nasa.gov/r/geoss/[GCMD]FIFE_STRM_15M ]

  • The BOREAS TE-06 team collected several data sets to examine the influence of vegetation, climate, and their interactions on the major carbon fluxes for boreal forest species. This data set contains summaries of predawn leaf water potentials and foliage moisture contents collected at the TF and CEV sites that had canopy access towers. The data was collected on a nearly weekly basis from early June to late August 1994 by TE-06, members of the BOREAS staff, and employees of Environment Canada. [ This document was provided by NASA's Global Change Master Directory. For more information on the source of this metadata please visit http://gcmd.nasa.gov/r/geoss/[GCMD]BOREAS_TE6H2OPD ]

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