نتایج جستجو برای: snow
تعداد نتایج: 17514 فیلتر نتایج به سال:
Snow is an important research interest in international cryosphere research. In China, cold region account for 43% of the total area (Yang et al., 2000). The area of stable snow where snow cover duration is greater than 60 days is approximately 420×104km2. In West China, the recharge to spring freshet from winter snow is a necessary regulation for spring drought (Qin et al., 2006). However, lar...
The objective of this work is to evaluate the use of the Medium Resolution Imaging Spectrometer (MERIS) data for seasonal snow cover monitoring specifically in the boreal forest belt. For this purpose, we tuned an existing method for fractional snow cover mapping in order to produce snow maps from MERIS imagery. The method was originally developed at the Finnish Environment Institute (SYKE), wh...
This project investigates how feasible it is to model and render snow in a three-dimensional environment, which could be added to a computer game to enhance its graphics. Falling snow and its collection are designed using particle systems, collision detection and surface modelling. We implement falling snow that appears relatively realistic using OpenGL and a particle system API. The feasibilit...
The evolution of snow depth in the central Spanish Pyrenees was analyzed using measurements from 106 snow stakes over a period of 14 yr (1985–1999). Relationships were considered between the regional series of snow depths at the end of winter and in the middle of spring with respect to precipitation and temperature in previous months. Both variables explained a large percentage of the interannu...
The properties of seasonal snow and near surface polar firn can be measured using radars operating at the microwave frequencies. These frequencies offer an optimal combination of bandwidth and penetration required for snow studies. Because the velocity of microwave signals in dry snow and firn is primarily controlled by density, wave travel times can be converted to snow depth, snow water equiv...
A detailed evaluation of climate conditions in a small alpine watershed, typical of much of the southern Sierra Nevada, is presented for the 1986 water year. Measurements of snowfall, meteorological and snow cover conditions, and snow cover ablation are used to characterize the climate at four locations in the watershed during that snow season. Data from these locations are then combined into t...
Snow plays an important role in providing atmospherically derived semi-volatile organic compounds (SVOCs) to regions of high latitude and altitude. The accumulated winter snowpack serves as a reservoir for SVOCs, which may then be released to arctic/alpine catchments during seasonal snowmelt or entrained into deeper layers of snow and ice. This paper provides a review of the occurrence of SVOCs...
We present scientific and computing improvements to our new reconstruction model compared to a previous model. Snow water equivalent (SWE) reconstruction involves building a snowpack up in reverse, from melt out to peak SWE, given estimates of melt energy and fractional snow covered area (fSCA). The model was initially tested at an energy balance site on Mammoth Mountain, near the Upper Tuolumn...
We have developed a new approach based on modelling and assimilation to combine SAR and optical data for snow cover area mapping. SAR data would typically be acquired a few times a week, while optical data is acquired daily but is limited by cloud cover. The algorithm we use analyses the current time series to estimate the current Fractional Snow Cover (FSC) per pixel. A set of snow states is d...
The Soil and Water Assessment Tool (SWAT) was used to simulate five glacierized river basins that are global in coverage and vary in climate. The river basins included the Narayani (Nepal), Vakhsh (Central Asia), Rhone (Switzerland), Mendoza (Central Andes, Argentina), and Central Dry Andes (Chile), with a total area of 85,000 km2. A modified SWAT snow algorithm was applied in order to consider...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید