Showing 4 results for shamsipour
Faeze Shoja, Salimeh Sadeghi, Shamsipour,
Volume 0, Issue 0 (3-1921)
Abstract
The aim of this research is to evaluate the heat mitigation index (HMI) in the Tehran metropolitan area using the Urban Cooling Model(UCM)approach in a spatial framework. UCM produces maps of the Heat Mitigation Index. This index estimates the cooling potential of urban green spaces in a given location, taking into account various parameters such as evapotranspiration, tree shading, albedo, rural reference air temperature, urban heat island intensity, air temperature maximum blending, and maximum cooling distance. The assessment of environmental factors influencing the UCM in the study area revealed that the urban heat island effect was least intense in regions 1, 22, and the northern parts of region 4 of Tehran municipality, where there are scattered trees, shrubs, open low-rise buildings, and water bodies. The temperature differential between the city and the suburbs ranged from 0 to 1.3 degrees Celsius. However, the study area's central parts showed the highest intensity of the urban heat island, particularly in regions 21, 13, and 14. These regions have a dense and compact texture and an expansion of impervious surfaces, resulting in the lowest values of the evapotranspiration index and albedo.Based on these parameters, the study area's HMI index showed that the cooling capacity varies from 0.08 in the central parts of the city to 0.9 in areas affected by green spaces and water bodies. The maximum cooling capacity index is concentrated in areas with dense and scattered tree cover in the region. On average, these areas have been able to neutralise 2.48 degrees Celsius of the urban heat island effect with a cooling capacity of 63%. The methodology employed in this research can be used as a reference for urban designers in integrating urban cooling approaches and heat island mitigation strategies in urban planning and design.
Mostafa Karimi, Ghasem Azizi, Aliakbar Shamsipour, Lila Rezaee Mahdi,
Volume 16, Issue 41 (6-2016)
Abstract
In this study is simulation of role of topography in thickness and Inland penetration of sea-breeze in southern coast of the Caspian Sea. The RegCM4 as a regional scale climate model coupled with a lake model and also the reanalysis data of NCEP / NCAR used to determine of the initial conditions of the model. The model was run during the peak of sea breeze on the southern coast of the Caspian Sea (July 2002) in both conditions (with mountains) and (without mountains). the outputs indicated that in without topography condition depth of the sea breeze will increase to the current position the southern slopes of the Alborz Mountains ( latitude ᵒ35 ) but the land breeze in the area is gone. The maximum speed and changes in wind direction observed on the coast southeast and central Alborz respectively. In addition with non-topography conditions, the thickness of sea breeze in different areas significantly has increased with the highest rate on the eastern coast (longitude ᵒ53).
Fatemeh Ghiasabadi Farahani, Faramarz Khoshakhlagh, Aliakbar Shamsipour, Ghasem Azizi, Ebrahim Fattahi,
Volume 18, Issue 48 (3-2018)
Abstract
The present research about the spatial changes of precipitation is mainly focused on western areas of Iran. Precipitation data for three seasons of fall, winter, and spring have been obtained from Esafzari Database, with 15*15 km spatial resolution in the form of a Lambert Cone Image System for the period from 1986 to 2015. To examine the prevailing pattern of precipitation in west of Iran, we have used geostatistical methods of spatial autocorrelation. The changes in precipitation trends have been analyzed using parametric and non-parametric analyses of regression and Mann Kendal. We have used MATLAB for analysis of the data. We have also used ArcGIS and Surfer for drawing maps. The results of inter-decade changes of positive spatial autocorrelation of precipitation in west of Iran have indicated that there has been a decline in spatial extent of the positive spatial autocorrelation pattern in spring and fall, except for winter with a negligible increasing trend. Nevertheless, except for the second period, no considerable spatial changes were observed in the spatial pattern of precipitation in the region. However, there was a decreasing trend in the negative spatial autocorrelation of precipitation in annual and seasonal scales. The results of trend analysis have indicated that there was a decreasing trend in a vast area of the west parts of the country in annual scale and also in winter. Although there was an increasing trend in precipitation in fall and spring, but the trend was not significant in 95 % of confidence interval. The results of Man Kendal test have confirmed the results obtained from linear regression.
Ms Zienab Hosinpoor, Dr. Aliakbar Shamsipour, Dr. Mostafa Karimi, Dr. Faramarz Khoshakhlagh,
Volume 23, Issue 68 (3-2023)
Abstract
Heat waves are important phenomena in Iran, And its upsurge in recent years seems to have a high upside trend.This climate has a negative impact on agriculture, forest fire and forestry, water resources, energy use and human health.The purpose of the research is to explain the frequency, time distribution, continuity of thermal waves, and the identification of its occurrence in the southern foothills of central Alborz.Therefore, using the statistical methods and maximum daily temperature data of Tehran (Mehrabad), Qazvin and Semnan stations for the statistical period of 30 years (1966-2016), the mentioned characteristics were extracted.In the first step, the nonparametric method of Kendal was used to understand the variability and awareness of the monthly trend of maximum temperatures in the study period.In order to determine the severity, duration and frequency of heat wave events, the percentiles (95.98) and normalized temperature deviation (NTD) were used.The results of the study showed that the frequency of short-wave heat waves was higher.Most frequencies are related to 2-day waves, respectively, and Tehran (Mehrabad), Semnan and Qazvin stations are more frequent.The highest frequency of annual events was detected at stations in Tehran (11 waves in 2010), in Semnan (9 waves in 2015) and Qazvin (7 waves in 2015), respectively.The highest frequency of monthly heat wave events was recorded in June and September.The highest continuation (15 days) was obtained in March 2008 with the percentile method at Mehrabad station.In the normalized deviation method, the temperature was calculated as a warm wave (12 days) in 2008.The highest annual frequency of heat loss occurred in all three stations in 2015.The evolution of the process indicated an increase in the incidence of thermal waves in the cold period of the year But in other chapters, no meaningful changes were made.As it says, the decline in cold winter temperatures is on the southern slopes of Alborz.The results of the two methods showed that in the normalized deviation of the temperature, the number of thermal waves more than the percentile method was recorded, but in the percentile method, the thermal wave was more prominent in the cold period of the year.