For later development of design snow loads, the water equivalent of snow on the ground appears to be the best The appropriate climatological series for this is the winter Among many distributions investigated, the lognormal Distributions fitted to 140 stations provided data In southern areas of the United States, where snow does This requires the A contour map is provided of the mixture paramet...

Ecotones are zones of gradual changes from an ecological system to another.Ecotones monitoring could be important to find out the reason for changes and limits. Inthis research satellite data were used to analyze the ecotone boundary in Fars steppicrangelands using IRS LISS III and Pan data of year 2006. The real vegetation map andecotones prepared through Geo-eye images from Google earth softw...

ecotones are zones of gradual changes from an ecological system to another.ecotones monitoring could be important to find out the reason for changes and limits. inthis research satellite data were used to analyze the ecotone boundary in fars steppicrangelands using irs liss iii and pan data of year 2006. the real vegetation map andecotones prepared through geo-eye images from google earth softw...

the consideration of tehran metropolis and its soundings areas has been the first one of recent challenges in iran’s spatial planning which made it possible to develop the concepts such metropolitan region and conurbation. however, it is obvious that there appears to be a much more proper structure due to neo-regionalism and globalization in order to understanding of dynamic nature of tehran an...

1. introduction glaciers and snow covers in the mountains play an important role in the water budget of many areas of the world (ramage and isacks, 2003). in high altitudes and mountainous regions, snowmelt is a great contributor to the yearly runoff. the snow melt supplies 1/6 of people's needed water but due to global warming these glaciers may be at risk (barnett, et al. 2005). for the regio...

Characterization of snow is critical for understanding Earth’s water and energy cycles. Maps of snow from MODIS have seen growing use in investigations of climate, hydrology, and glaciology, but the lack of rigorous validation of different snow mapping methods compromises these studies. We examine three widely used MODIS snow products: the ‘‘binary’’ (i.e., snow yes/no) global snow maps that we...

snow cover area is one of the most important criteria to calculate snow melt runoff. this can have an effect on the biology of the plant and the environment of a region. using the catchment basin physical characteristic to calculate snow cover area is a conventional method, though its accuracy is not good enough. most of the useful methods in calculating snow cover area are based on satellite i...