The synoptic variation of the atmospheric radio refractive index, evaluated from standard weather observations, is examin ed d uri ng an ou t break of polar continental air. It is found t hat t he reduced-t o-sea-Ieve1 value of t he r efractive index is a more sensitive synoptic parameter t han t he station value. The reduced valu e is quite sensit ive to the humidity and density structure of t...

the writers of this research have studied seven variables including: precipitation, relative humidity, sunny hours, temperature average, temperature minimum, temperature maximum and sea level pressure, at sanandaj air station during 1964-1994. sanandaj air station has nearly 10966 days of complete data for these variables. a principal component analysis (pca) has been applied on this data; then...

We report on the development and validation of a neural network (NN) model of PM10 concentrations in terms of photochemical measurements of NO, NO2 and O3 and temporal parameters that include the day of the week and the day of the year with its sinusoidal variation. A long-term record (≈10 yr) from 2001–2012 (inclusive) assembled from measurements taken at 10 station nodes in the air quality mo...

abstract nowadays, solar energy as one of the most important sources of clean and free of damaging environmental effects energy are used in many cases including generation of electricity, heat and desalination of salt water. the purpose of this research is identification of high radiation areas as most suitable regions for these applications.to do this, cloudiness data of 120 synoptic stations ...

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...

sensitivity analysis to determine variations in evapotranspiration is much important considering a known variation in one of climatic variables. in this study, sensitivity of evapotranspiration from penmann-mantith, penmann-kimberly (1996), penman-kimberly (1972) and penmann (1984)  and hargrivs (1985) approaches to three climatic variations (maximum temperature, wind speed, solar radiation) wa...

Precipitation is the only water supply and most important factor affecting vegetation growth on the slopes of semi-arid Loess Plateau of China. Based on precipitation data from 7 synoptic stations in the study area over the period 1957-2012, the trends of precipitation and standardized precipitation index (SPI) were analyzed by using linear regression, Mann-Kendall, and Spearman's Rho tests at ...