abstract in order to evaluation the effects of price policies (wheat guarantee price in each period and its price lag), environmental (planted area) and climatic (min and max average temperature, total annual precipitation, cold-day degree and hot-day degree) factors, we considered wheat yield in razavi-khorasan province (9 cities) for a 13-year statistical period (1371-72 to 1383-84). in this ...

Epidemiological studies around the world have reported that fine particulate matter (PM2.5) is closely associated with human health. The distribution of PM2.5 concentrations is influenced by multiple geographic and socioeconomic factors. Using a remote-sensing-derived PM2.5 dataset, this paper explores the relationship between PM2.5 concentrations and meteorological parameters and their spatial...

Hydrologic regime is highly dependent on climate change, as hydrologic cycle components are directly influenced by climatic conditions. This paper analyzes the impacts of climate change on the hydrologic regime of the Atrak River basin in the northeast of Iran. It drains to the Caspian Sea. The data collected at 11 hydrometeorological stations were examined to detect trends in hydroclimatologic...

seasonal and annual precipitation increased, except in the summer; the annual precipitation increased by about one millimeter pre year over the last 52 years. The spring precipitation significantly increased at the 99 % confidence level, while the mean summer precipitation insignificantly decreased at the 95 % confidence level. The extreme precipitation, including the maxima and minima, also ex...

Spatial and temporal variability analysis of precipitation is an important task in water resources planning and management. This study aims to analyze the spatial and temporal variability of precipitation in the northeastern corner of Iran using data from 24 well-distributed weather stations between 1991 and 2015. The mean annual rainfall, precipitation concentration index (PCI), and their coef...

Extreme precipitation events are the major causes of severe floods in China. In this study, four time series of daily, 2-day, 5-day, and 10-day annual maximum precipitation from 1951 to 2000 at 651 weather stations in China were analyzed. The generalized extreme value (GEV) distribution was used, to model the annual extreme precipitation events at each station. The GEV distribution was also mod...

Based on a high-quality dataset of 713 daily precipitation series, changes in daily precipitation events during 1960–2013 were observed in China’s ten largest river basins. Specifically, the amount of precipitation in four categories defined by fixed thresholds and their proportion on total precipitation were analyzed on annual and seasonal time scales. Results showed annual precipitation incre...

The hydrological response due to potential CO,~forced climate change in the Black Hills of South Dakota was investigated using modelling techniques that include variations to atmospheric CO,, temperature, and precipitation. The Soil and Water Assessment Tool (SWAT) was used to model the 427 km Spring Creek basin hydrology and simulate the impact of potential climate change. As expected, modelli...

abstractprecipitation could be regarded as a complex and a very vital element in the earth atmosphere and its spatial-temporal changes can control iran's climate. in the current research, in order to model the spatial-temporal changes of annual precipitation, the data taking from 50 synoptic stations, have been analyzed during the years 1966-2005, with a suitable distribution. the most dat...

this study was carried out in sorkhdeh rangeland in semnan province in order to determine the ecological species groups and their relationships with environmental factors as a tool for better management. vegetation sampling was performed in 230 plots under equal random classification method and soil samples were taken in 0-15 depth. climatic and topographic data were extracted by overlaying sam...