Spatially localized refractivity variations, mainly due to water vapor, are a major source of error in high-precision positioning techniques such as GPS and SAR interferometry. Refractivity induced delay variations can be misinterpreted as, e.g., crustal deformation signal or positioning biases. In this study, signal delay estimates based on SAR observations and simultaneous GPS time series are...

An algorithm for simulating wind-ripples and moving sand is extended by the detection of fixed objects. This permits us simulation and animation of sand interacting with objects like houses, highways, cactuses, etc. Sand is accumulated on the windward side of an obstacle and the sand relocation and wind-ripples formation is diminished on the leeward side. The wind shadow depends on the object’s...

in the current research, wind energy potential at yazd synoptic stations, which contain wind data with 10 years statistic period and beyond, including yazd synoptic station (1976-2006), tabass (1987-2006), robate poshte badam (1992-2006), bafgh (1993-2006) and marvast (1997-2006), has been studied. wind data were obtained from the recorded data at yazd meteorology organization. the data were re...

dust is a common atmospheric phenomenon in iran especially in central arid regions.  this severely affects environment as well as resident’s health. among the results of this phenomenon are respiratory diseases, bash radiation, accelerated soil erosion, desertification and degradation of ecosystems. some dusts are originated from local desert conditions but adjacency to neighboring countries de...

Paired trap lines of Þve boll weevil pheromone traps each were placed on opposite sides of a brush line at six different sites on a plantation in the Lower Rio Grande Valley of Texas. Temperature, wind speed, and wind direction were monitored with a nearby weather station. We observed a strong negative relationship between mean daily wind speed and total daily capture of boll weevils. About hal...

Spatially localized refractivity variations, mainly due to water vapor, are a major source of error in high-precision positioning techniques such as GPS and SAR interferometry. Refractivity induced delay variations can be misinterpreted as, e.g., crustal deformation signals or positioning biases. In this study, signal delay estimates based on SAR observations and simultaneous GPS time series ar...

Wind has become increasingly important as a source of energy although the generation of wind energy is quite erratic because of its changeable nature. For a given location, wind speed and direction change over time and at different heights. Previous studies have discovered different pattern of wind profiles, however an improved understanding of its spatial, temporal and variation in heights is ...

In this paper, an overview of new and current developments in wind forecasting is given where the focus lies upon principles and practical implementations. High penetration of wind power in the electricity system provides many challenges to the power system operators, mainly due to the unpredictability and variability of wind power generation. Although wind energy may not be dispatched, an accu...