X/P Merge is a computer program that estimates ground-surface elevations and vegetation heights from multiple sets of data acquired by the GeoSAR instrument. Siqueira, Paul Hensley, Scott Rodriguez, Ernesto Simard, Marc Program Merges SAR Data on Terrain and Vegetation Heights Our results show potential to establish a high resolution pan-arctic vegetation height map, which will provide useful information to a broad range of ongoing and future ecological research in high northern latitudes. This predicted vegetation height dataset also led to the development of a digital terrain model using the ArcticDEM digital surface model by removing canopy heights from the surface heights. Vegetation height was successfully predicted across the three study areas and evaluated using an independent dataset, with R2 ranging from 0.58 to 0.76 and RMSEs ranging from 1.8 to 2.4 m. We developed a RandomForest modeling approach for predicting vegetation height using the ArcticDEM (a digital surface model produced across the Arctic by the Polar Geospatial Center) and high-resolution multispectral satellite data (WorldView-2) in conjunction with aerial lidar data for calibration and validation. To accomplish this, we selected three study areas across a north-south gradient in Alaska, representing an area of approximately 130 km2. Our objective was to develop and test an approach that allows for mapping vegetation height at a 5m grid cell resolution across the ABoVE domain. High-resolution data products that quantify vegetation structure and function will improve efforts to assess these environmental change impacts. Recently, NASA initiated the Arctic-Boreal Vulnerability Experiment (ABoVE), which is a large-scale field campaign that aims to gain a better understanding of how the arctic responds to environmental change. Ecological processes are highly responsive to temperature and therefore substantial changes in these northern ecosystems are expected. Wulder, M.īoreal and arctic regions are warming at an unprecedented rate, and at a rate higher than in other regions across the globe. Thirdly, the GLAS global vegetation height product is compared with aĮstimating Vegetation Height from WorldView-02 and ArcticDEM Data for Broad Ecological Applications The changes in height estimates by applying different filters are, for the main part, smaller than the overall uncertainty of 4.5–6 m established from the site measurements. Secondly, the global aggregated GLAS vegetation height product is tested for sensitivity towards the choice of data quality filters areas with frequent cloud cover and areas with steep terrain are the most sensitive to the choice of thresholds for the filters. Application of filters to the GLAS vegetation height estimates increases the correlation with aircraft data from r = 0.33 to r = 0.78, decreases the root-mean-square error by a factor 3 to about 6 m (RMSE or 4.5 m (68% error distribution and decreases the bias from 5.7 m to −1.3 m. Firstly, the Vegetation height data and data filters are evaluated using aircraft LiDAR measurements of the same for ten sites in the Americas, Europe, and Australia. The GLAS vegetation height product is evaluated in four ways. Filtered GLAS vegetation height estimates are aggregated in histograms from 0 to 70 m in 0.5 m intervals for each 0.5° Ã- 0.5°. data that are affected by clouds, atmosphere and terrain and as such result in erroneous estimates of vegetation height or vegetation cover. Filters are developed to identify and eliminate spurious observations in the GLAS data, e.g. (2008 with with further calibration on desert sites. Initial vegetation height is calculated from GLAS data using a development of the model of Rosette et al. The data sets are derived from 2003–2009 measurements collected by the Geoscience Laser Altimeter System (GLAS on the Ice, Cloud and land Elevation Satellite (ICESat, the only LiDAR instrument that provides close to global coverage. Vegetation height and cover fraction between 60° S and 60° N from ICESat GLAS dataĭirectory of Open Access Journals (Sweden)įull Text Available We present new coarse resolution (0.5° Ã- 0.5° vegetation height and vegetation-cover fraction data sets between 60° S and 60° N for use in climate models and ecological models.
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