in order to identify the pressure patterns causing the cold weather over the northwestern iran, daily lowest temperatures of six stations of the study area during january- march months of the 1986-2003 period were obtained from meteorological organization of islamic republic of iran (irimo) in the quality controlled format. according to the defined threshold, the very cold days were extracted a...

The present article is aimed at study on agroclimatic conditions of cultivation of sunflower throughout selected substations at Kurdistan  Province by means of GIS system. In this investigation, meteorological data have been received from synoptic stations based on daily, monthly, and annually trend from Iran Meteorological Organization (IMO) at Kurdistan  Province and then homogeneity of data ...

A feeding station is the area of forage a grazing animal can reach without moving its forefeet. Grazing behavior can be divided into residence within feeding stations (with bites as benefits) and movement between feeding stations (with steps as costs). However, relatively little information has been reported on how grazing animals modify their feeding station behavior seasonally and interannual...

We analyze surface air temperature data from available meteorological stations with principal focus on the period 1880-1985. The temperature changes at midand high latitude stations separated by less than 1000 km are shown to be highly correlated; at low latitudes the correlation falls off more rapidly with distance for nearby stations. We combine the station data in a way which is designed to ...

The arid zones of the world are all characterized by a large deficit of rainfall in relation to the potential evapotranspiration. Their distribution around the world is governed by the interaction of global atmospheric circulation patterns, the distribution of land and sea, and local topography. Countries that have substantial areas with arid conditions belong to very different groups in terms ...

Mountain waters, glaciers, hazards, and biodiversity are vulnerable to the impacts of global warming. Warming is projected to amplify over mountains by global climate models, yet meteorological records do not show a uniform acceleration of warming with elevation. Here we explore warming-elevation relationships using records from 2660 meteorological stations and determine that the vertical gradi...

background: forecasting of air pollutants has become a popular topic of environmental research today. for this purpose, the artificial neural network (aan) technique is widely used as a reliable method for forecasting air pollutants in urban areas. on the other hand, the evolutionary polynomial regression (epr) model has recently been used as a forecasting tool in some environmental issues. in ...