Urbanization Effect on Air Temperature in Iran's Zayanderud River Basin

: Detection of urbanization effect to understand climate change is important. Urbanization effect on air temperature in Zayanderud river basin was evaluated using weather stations network. Map of the temperature trend was generated using full dataset and rural stations to visualize warming trends. A comparative analysis was carried out to estimate urban heat island effect. The result indicated that overall warming trend in the basin is 0.012°C year-1 and the contribution of urban warming to total temperature change was estimated to be 17%. Variation of urban warming throughout the basin was 0-0.016°C year-1. The centre of a basin with a large UHI effect by 0.006-0.016°C year-1 is more influenced by urbanization. Records of hemispheric mean temperatures from ground areas for the past 100 years prepare pivotal input to the argument over global warming. Contrary to precise apply of the basic station data in some of these collections of hemispheric temperature, there have been proposals that a ration of the 0.5°C warming seen on a century timescale may be related to urbanization affections-local warming caused by the effects of urban enlargement. The consequences display that the urbanization affection in two of the most widely used hemispheric data sets is, at most, an order of quantity less than the warming seen on a century timescale. The climatic alternations of the temperature are considered. Gridded temperature data are necessary to run ecological models at regional scales for climate impact studies and have been generated by spatially incorporating preceded values at synoptic stations.