introduction long-term annual extreme climate events, especially temperature and precipitation, have generally been used as indicators for the assessment of climate change. one of the most changeable climatic variables in time and space is precipitation. there are great number of research papers focusing on extreme precipitation on global, regional and national scales have been written. the res...

climate change phenomenon is an important environmental challenge of the world. increasing extension of greenhouse gases and remote relationship phenomena accelerate the speed f climate change. changes in precipitation level, drought occurrence and changes in the level of surface and groundwater resources are the recognized consequences of climate change. in order to study consequences of clima...

Abstract The Standard Precipitation Index (SPI) is a widely used statistical technique for the characterization of droughts. It based on probabilistic standardization procedure, which converts Gamma-type probability distribution function (PDF) into normal (Gaussian) standard series with zero mean and unit deviation. Drought classification SPI indicates dry wet spell characteristics, provided th...

in recent decades, neyshabour basin as a semi-arid climate has faced with dramatic increasing of groundwater withdrawal. so, water demand management is important in this basin. in this study, the effects of evapotranspiration and rainfall on groundwater fluctuations have been considered with 22 rain gage and evaporation gage station data during 1973-2006. the average amount of rainfall and evap...

Drought is one of the major natural hazards that bring about billions of dollars in loss to the farming community around theworld each year. Drought is most often caused by a departure of precipitation from the normal amount, and agriculture is often the first sector to be affected by the onset of drought due to its dependence on water resources and soil moisture reserves during various stages ...

[1] Precipitation data for Seoul, Korea, have been recorded since 1778, representing one of the world’s longest instrumental measurements of daily precipitation. Trends in summer precipitation amount, intensity, and indices of climate extremes are studied. The detected trends were tested using trend-to-noise ratio test, nonparametric Mann– Kendall rank statistic and Monte Carlo simulation proce...

in this research, the daily precipitation data of 1437 synoptic, climatic and rain gauging stations of iran in the time interval 1961- 2004 (equal to 15705 days) was utilized. using kriging geostatistics method, the data were interpolated on the pixels of 15 *15km2, so as an array to the dimension of 15705 * 7187 was formed. to identify the fittest distribution of the days with over 5.0mm preci...