Filters: Tags: Baseline 1-High Resolution Landcover Imaging (X)193 results (75ms)
Evaluating GCM outputs for past climates in North America based on the distribution of Sphagnum peatlands
Application of time-lapse digital imagery for ground-truth verification of satellite indices in the boreal forests of Alaska
Use of remote sensing to identify areas of groundwater upwelling on active glacial floodplains: Their frequency, extent and significance on a landscape scale
The evolution of permafrost in cold regions is inextricably connected to hydrogeologic processes, climate, and ecosystems. Permafrost thawing has been linked to changes in wetland and lake areas, alteration of the groundwater contribution to streamflow, carbon release, and increased fire frequency. But detailed knowledge about the dynamic state of permafrost in relation to surface and groundwater systems remains an enigma. Here, we present the results of a pioneering 1,800 line-kilometer airborne electromagnetic survey that shows sediments deposited over the past 4 million years and the configuration of permafrost to depths of 100 meters in the Yukon Flats area near Fort Yukon, Alaska. The Yukon Flats is near the...
Denali National Park and Preserve Landcover Mapping Project Volume 2: Landcover classes and plant associations
This paper discusses the application of digital terrain analysis modeling techniques to the parameterization of a semi-distributed hydrologic model. Most current techniques for deriving physiographic parameters in watershed analyses, including those using commercial geographic information systems (GIS), are tedious, costly and time consuming. The demands of these techniques result in them usually being limited in practical application to deriving parameters at only one level of detail or for only one set of sub-basins. This paper presents a computerized interface (SLURPAZ) that was developed to combine the output of an established digital terrain analysis model (TOPAZ) with digital land cover data to derive all...
Application-Ready Expedited MODIS Data for Operational Land Surface Monitoring of Vegetation Condition
Interactions of multiple disturbances in shaping boreal forest dynamics: a spatially explicit analysis using multi-temporal lidar data and high-resolution imagery
1.?Mixed-wood boreal forests are often considered to undergo directional succession from shade-intolerant to shade-tolerant species. It is thus expected that overstorey gaps should lead to the recruitment of shade-tolerant conifers into the canopy in all stand development stages and that the recruitment of shade-intolerant hardwoods would be minimal except in the largest gaps. 2.?We analysed short-term gap dynamics over a large 6-km2 spatial area of mixed-wood boreal forest across a gradient of stands in different developmental stages with different times of origin since fire (expressed as stand ?age?) that were affected differentially by the last spruce budworm (SBW) outbreak. Structural measurements of the canopy...
SPARC: New Cloud, Snow, and Cloud Shadow Detection Scheme for Historical 1-km AVHHR Data over Canada
The identification of clear-sky and cloudy pixels is a key step in the processing of satellite observations. This is equally important for surface and cloud-atmosphere applications. In this paper, the Separation of Pixels Using Aggregated Rating over Canada (SPARC) algorithm is presented, a new method of pixel identification for image data from the Advanced Very High Resolution Radiometer (AVHRR) on board the NOAA satellites. The SPARC algorithm separates image pixels into clear-sky and cloudy categories based on a specially designed rating scheme. A mask depicting snow/ice and cloud shadows is also generated. The SPARC algorithm has been designed to work year-round (day and night) over the temperate and polar regions...
A test of detecting spring leaf flush within the Alaskan boreal forest using ERS-2 and Radarsat SAR data
We present a comprehensive approach to carry out community-wide assessments of in situ conservation of forest trees based on basic botanical and ecological data. This is a first step, resulting in a consistent framework to set priorities for collection and inclusion of species- specific biological and genetic information. We use botanical sample data to generate high-resolution distribution maps as a basis for a gap analysis of how well each species is represented in protected areas. To account for adaptive genetic variation of tree species we stratify populations by ecological zones that represent different macroclimates. In a detailed example for Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), we show that...
Denali National Park and Preserve Landcover Mapping Project Volume 1: Remote Sensing Data, Procedures and Results
The influence of ground- and lidar-derived forest structure metrics on snow accumulation and ablation in disturbed forests