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Snow covered area (SCA) observations from the Landsat Enhanced Thematic Mapper (ETM+) were used in combination with a distributed snowmelt model to estimate snow water equivalent (SWE) in the headwaters of the Rio Grande basin (3,419 km2) - a spatial scale that is an order of magnitude greater than previous reconstruction model applications. In this reconstruction approach, modeled snowmelt over each pixel is integrated over the time of ETM+ observed snow cover to estimate SWE. Considerable differences in the magnitude of SWE were simulated during the study. Basin-wide mean SWE was 2�6 times greater in April 2001 versus 2002. Despite these climatological differences, the model adequately recovered SWE at intensive...
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Final Report - Executive Summary: This final project report is prepared to summarize the research project titled “Assessing evapotranspiration rate changes for proposed restoration of the forested uplands of the Desert Landscape Conservation Cooperatives (LCC)” for the Desert LCC of the Bureau of Reclamation as a requirement for closing out the project. This report includes the scope of work, summary of research project, results, and conclusions.Among all of the components of the terrestrial water cycle, evapotranspiration (ET) consumes the largest amount of water. Accurate estimation of ET is very important to understand the influence of ET to the hydrologic response of recharge and runoff processes in the water...
Categories: Data, Publication; Types: Citation, Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: 2012, ATMOSPHERE, ATMOSPHERE, ATMOSPHERIC WATER VAPOR, ATMOSPHERIC WATER VAPOR, All tags...
Abstract (from http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-15-0088.1): A comprehensive understanding of the spatial, seasonal, and diurnal patterns in cloud cover frequency over the Hawaiian Islands was developed using high-resolution image data from the National Aeronautics and Space Administration’s Moderate Resolution Imaging Spectroradiometer (MODIS) sensors aboard the Terra and Aqua satellites. The Terra and Aqua MODIS cloud mask products, which provide the confidence that a given 1-km pixel is unobstructed by cloud, were obtained for the entire MODIS time series (10-plus years) over the main Hawaiian Islands. Monthly statistics were generated from the daily cloud mask data, including mean cloud cover...
Encroachment of the shrub Prosopis glandulosa Torr. (honey mesquite) into semi-arid grasslands is a serious concern in the south-western United States, yet little is known about the long-term dynamics of the invasion process. We used ten high-resolution aerial and satellite images taken from 1936 to 1996 to track the population dynamics and spatial pattern of all P. glandulosa greater than 2 m in diameter on a 75 ha area in southern New Mexico. Shrub cover and patch numbers increased from 1936 to the 1970s, then stabilized at 43% cover and 83 patches ha?1. Individual patches were extremely persistent: 95% of the area occupied by shrub patches in 1936 was still occupied in 1996. Recruitment into the 2 m size class...
Buildings and other engineered structures that form cities are responsible for a significant portion of the global and local impacts of climate change. Consequently, the incorporation of building design strategies and materials such as the use of reflective roof materials, or [`]cool' roofs, are being widely investigated. However, although their benefits for individual buildings have been studied, as yet there is little understanding of the potential benefits of urban scale implementation of such systems. Here we report the development of a new methodology for assessing the potential capacity and benefits of installing reflective roofs in an urbanized area. The new methodology combines remote sensing image data...
Quantitative assessment of forest burn severity and determination of its spatial variation are important for post-fire forest restoration and forest fire management. In this paper, we assessed forest burn severity using pre- and post-fire Landsat TM/ETM+ data and field-surveyed data and explored the spatial variation in burn severity and its influencing factors. Our results showed a relatively strong linear relationship between normalized burn ratio (NBR) and composite burn index (CBI) (R2 = 0.63), suggesting that NBR was the best spectral index and could be used to assess forest burn severity in Heilongjiang Province. The forest burn severity showed obvious spatial variation. The majority of heavily burned areas...
We develop a new framework, based on Landsat time series data and forest inventories, to estimate the carbon in roundwood harvested from forest management activities, which will enter the HWP pool and remain stored in end uses and landfills. The approach keeps the distinction between the carbon from different types of roundwood sources, which allows for better integration with the regional HWP carbon lifetime information. We show that existing methods that are based on large scale regional/national values and linear interpolation of data gaps, can provide only very approximate carbon estimates. The model was applied to a US state using county level data, but can also suit different areas as long as sufficient harvest...
Abstract (from: http://www.igsoc.org/journal/60/221/j13J176.html): The Randolph Glacier Inventory (RGI) is a globally complete collection of digital outlines of glaciers, excluding the ice sheets, developed to meet the needs of the Fifth Assessment of the Intergovernmental Panel on Climate Change for estimates of past and future mass balance. The RGI was created with limited resources in a short period. Priority was given to completeness of coverage, but a limited, uniform set of attributes is attached to each of the ~198 000 glaciers in its latest version, 3.2. Satellite imagery from 1999–2010 provided most of the outlines. Their total extent is estimated as 726 800 +/- 34 000 km2. The uncertainty, about +/-...
Climate change coupled with an intensifying wildfire regime is becoming an important driver of permafrost loss and ecosystem change in the northern boreal forest. There is a growing need to understand the effects of fire on the spatial distribution of permafrost and its associated ecological consequences. We focus on the effects of fire a decade after disturbance in a rocky upland landscape in the interior Alaskan boreal forest. Our main objectives were to (1) map near-surface permafrost distribution and drainage classes and (2) analyze the controls over landscape-scale patterns of post-fire permafrost degradation. Relationships among remote sensing variables and field-based data on soil properties (temperature,...
The North American Monsoon (NAM) is characterized by seasonal precipitation pulses which produce a considerable impact on land surface conditions. Changes in land surface processes have received less attention among the factors that concurrently influence the NAM. In this study, we utilize remotely-sensed and ground-based measurements to infer land surface changes that can influence the NAM through a vegetation?rainfall feedback mechanism. Our study is focused over the period 2004?2007 in northwest Mexico. Results from the analysis of remote sensing data indicate that the ground observations at an eddy covariance tower are representative of the land surface dynamics in subtropical scrublands. The extensive subtropical...
Groundwater resources are being overexploited in arid and semi-arid environments globally, which necessitates a deeper understanding of the roles that groundwater plays in earth system processes. Of particular importance is the elucidation of groundwater's effect on the generation of atmospheric dust. While many spatially extensive, highly productive dust sources are influenced to some degree by water resource use, including groundwater pumping and other modifications to shallow groundwater tables (<10 m from the surface), links between near-surface groundwater processes and dust production have only recently been identified. Processes associated with shallow groundwater tables include the vertical movement of salts...
The North American Monsoon (NAM) is characterized by seasonal precipitation pulses which produce a considerable impact on land surface conditions. Changes in land surface processes have received less attention among the factors that concurrently influence the NAM. In this study, we utilize remotely-sensed and ground-based measurements to infer land surface changes that can influence the NAM through a vegetation–rainfall feedback mechanism. Our study is focused over the period 2004–2007 in northwest Mexico. Results from the analysis of remote sensing data indicate that the ground observations at an eddy covariance tower are representative of the land surface dynamics in subtropical scrublands. The extensive subtropical...
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With extraordinary resolution and accuracy, Light Detection and Ranging (LiDAR)-derived digital elevation models (DEMs) have been increasingly used for watershed analyses and modeling by hydrologists, planners and engineers. Such high-accuracy DEMs have demonstrated their effectiveness in delineating watershed and drainage patterns at fine scales in low-relief terrains. However, these high-resolution datasets are usually only available as topographic DEMs rather than hydrologic DEMs, presenting greater land roughness that can affect natural flow accumulation. Specifically, locations of drainage structures such as road culverts and bridges were simulated as barriers to the passage of drainage. This paper proposed...
Abstract (from http://www.sciencedirect.com/science/article/pii/S0034425716302619): Groundwater dependent ecosystems (GDEs) rely on near-surface groundwater. These systems are receiving more attention with rising air temperature, prolonged drought, and where groundwater pumping captures natural groundwater discharge for anthropogenic use. Phreatophyte shrublands, meadows, and riparian areas are GDEs that provide critical habitat for many sensitive species, especially in arid and semi-arid environments. While GDEs are vital for ecosystem services and function, their long-term (i.e. ~ 30 years) spatial and temporal variability is poorly understood with respect to local and regional scale climate, groundwater, and...
High-latitude regions are experiencing rapid and extensive changes in ecosystem composition and function as the result of increases in average air temperature. Increasing air temperatures have led to widespread thawing and degradation of permafrost, which in turn has affected ecosystems, socioeconomics, and the carbon cycle of high latitudes. Here we overcome complex interactions among surface and subsurface conditions to map near-surface permafrost through decision and regression tree approaches that statistically and spatially extend field observations using remotely sensed imagery, climatic data, and thematic maps of a wide range of surface and subsurface biophysical characteristics. The data fusion approach...
Buildings and other engineered structures that form cities are responsible for a significant portion of the global and local impacts of climate change. Consequently, the incorporation of building design strategies and materials such as the use of reflective roof materials, or [`]cool' roofs, are being widely investigated. However, although their benefits for individual buildings have been studied, as yet there is little understanding of the potential benefits of urban scale implementation of such systems. Here we report the development of a new methodology for assessing the potential capacity and benefits of installing reflective roofs in an urbanized area. The new methodology combines remote sensing image data...
Abstract (from http://www.sciencedirect.com/science/article/pii/S0034425716303261): Wildfires shape the distribution and structure of vegetation across the inland northwestern United States. However, fire activity is expected to increase given the current rate of climate change, with uncertain outcomes. A fire impact that has not been widely addressed is the development of unburned islands; areas within the fire perimeter that do not burn. These areas function as critical ecological refugia for biota during or following wildfires, but they have been largely ignored in methodological studies of remote sensing assessing fire severity under the assumption that they will be detected by algorithms for delineating fire...
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Riparian grasslands dominated by big sacaton (Sporobolus wrightii) once covered floodplains across the southwest, but have been reduced to some 5% of their historical extent. Sacaton stands that remain provide key resources for watershed function, wildlife, and livestock—yet may need special management to sustain these benefits. This report describes mapping methods and management recommendations that can be applied to riparian grasslands throughout the region. By examining sacaton grasslands in the Las Cienegas National Conservation Area, this project also refines methods for evaluating ecological condition, and provides managers at this site with detailed maps of both high-quality habitat and restoration needs.
The estimation of surface-subsurface water interactions is complex and highly variable in space and time. It is even more complex when it has to be estimated in urban areas, because of the complex patterns of the land-cover in these areas. In this research a modeling approach with integrated remote sensing analysis has been developed for estimating water fluxes in urban environments. The methodology was developed with the aim to simulate fluxes of contaminants from polluted sites. Groundwater pollution in urban environments is linked to patterns of land use and hence it is essential to characterize the land cover in a detail. An object-oriented classification approach applied on high-resolution satellite data has...
Conventional measurements of river flows are costly, time-consuming, and frequently dangerous. This report evaluates the use of a continuous wave microwave radar, a monostatic UHF Doppler radar, a pulsed Doppler microwave radar, and a ground-penetrating radar to measure river flows continuously over long periods and without touching the water with any instruments. The experiments duplicate the flow records from conventional stream gauging stations on the San Joaquin River in California and the Cowlitz River in Washington. The purpose of the experiments was to directly measure the parameters necessary to compute flow: surface velocity (converted to mean velocity) and cross-sectional area, thereby avoiding the uncertainty,...
map background search result map search result map Sacaton Riparian Grasslands Report and Publications: Assessing Evapotranspiration Rate Changes for Proposed Restoration of the Forested Uplands of the DLCC Drainage Structure Datasets and Effects on LiDAR-Derived Surface Flow Modeling Sacaton Riparian Grasslands Drainage Structure Datasets and Effects on LiDAR-Derived Surface Flow Modeling Report and Publications: Assessing Evapotranspiration Rate Changes for Proposed Restoration of the Forested Uplands of the DLCC