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Showing 63 results for Iran

Dr. Mahmoud Dehghan, Dr. Ataalah Abdi, Dr. Afshin Mottaghi, Dr. Mirhadi Hosseini,
Volume 0, Issue 0 (3-1921)
Abstract

In geopolitics literature, small and low-endowment states that compound lesser geopolitical potentiality and weight are considered as the trivial scale agents in comparison with the first and second level powers. These agents, in spite of the local geopolitical codes but sometimes can effect on the regional and even global events of geopolitics. The Caucasian region, historically, have had a field for appearance and exposition of sub-khans that their overall actions and agencies effected the events of the region and due to its cultural proximities to Iran, have effected in Iran’s geopolitical functions in national scale. The present paper with descriptive-analytical method, have studied historical role of the local agencies in geopolitical events of the Caucasia and their impression on the great scale events. Secondly, the paper has studied the quality of the chosen countries of the region in current circumstances of the global system. Results indicate that the Caucasian countries act according to their historical legacy as a small-scale agents among the great scale actors.
Zeinab Ebrahimighalelani, Dr Javad Khoshhal Dastjerdi, Dr Hojatolah Yazdanpanah,
Volume 0, Issue 0 (3-1921)
Abstract

plants needs a certain amount of heat at the time of planting and during its growth period, The temperature requirements of the 704 single-cross cultivar of maize in Moghan weather conditions have been found in this study to determine its temperature requirements in its different growing stages in order to investigate the feasibility of its planting in the north west regions of Iran. Daily weather statistics presenting the minimum, maximum and average temperature of 51 Synoptic stations from Meteorological Organization of Iran have been used in this study, their statistical periods range from 1 to 30 years (1365-1395), the statistics and information about 5 main phenology stages of 704 single-cross variety maize which are recorded continually in Agricultural Weather Service of Moghan station in Pars Abad from 1390 to 1391 are provided. Then the 15-day averages from April 21st to July 22nd is obtained. The relationship between the temperature and the height in the linear regression is calculated .Map of heat supply date for seed sowing in all stations from the first half of May was drawn in the GIS. The plant collective growth degree days and the number of days in every phenology phase are calculated for all of the stations and the related maps are plotted.Then,the final map plotted by combining the layers thermal, height, slope and land use in the study area. The results of this study only 27.6% of the study area is able of maize cultivating.

Rastegar Mohammadi, Mohammad Saligheh, Mohammad Hossein Naserzadeh, Mehri Akbari,
Volume 0, Issue 0 (3-1921)
Abstract

Extratropical cyclones according to the frequency, duration, and intensity, the major cause of mid-and high-latitude precipitation across the Mediterranean during winter and autumn. For this research using network data of ECMWF climatic variables with 6-hour time resolution and 0.25 × 0.25 spatial resolution from1979-2016 and were used of 4 Basin stations precipitation data from the Asfezari database from 1979-2016. The results showed that the first pattern is the Mediterranean trough pattern which has the highest frequency of 42%. In this pattern, the low-level due to the presence of a high-level that acts as a barrier have caused the deepening of the Mediterranean low-level and its axis extends to the Red Sea, and due to the collision of low-level and high-level on the region, instability is intensified and has caused the most rainfall among the patterns.  In contrast to the first pattern, The fourth pattern has the lowest frequency of 10% Which is the trough pattern of western winds which is located on the Caspian Sea but due to high-level in the south of the region has prevented the entry of low-level and is located in the northern part of the study area due to this, the isobar in the north of the region have become orbital as a result, fewer cyclones enter the area, resulting in less rainfall between patterns. The results also showed that the frequency of cold-core cyclones was 60% in winter and 40% in autumn, but the frequency of hot core cyclones was 62% in winter and 38% in autumn, which in winter, the frequency of hot core cyclones has increased compared to cold-core cyclones, while in the fall the frequency of hot-core cyclones has decreased compared to cold-core. In the last decade, both the frequency of occurrence of cyclones and their intensity has decreased compared to the last two decades. In terms of cyclogenesis places, the western part of the study area has always been active, And with the onset of the cold season from autumn to winter, cyclogeneses places are gradually becoming more active.

Fardin Kooshki, Hamidreza Varesi,
Volume 0, Issue 0 (3-1921)
Abstract

از مسائل مهم حاکم بر مدیریت و برنامه­ریزی شهرهای ما، نگرش فرم محور است؛ یعنی می خواهند مسائل شهرها را عمدتاً از طریق تغییرات کالبدی حل کنند و در مطالعات خود بر ویژگی های فیزیکی تاکید دارند. در مقابل این نگرش، دیدگاه فرایند محور قرار دارد که سعی می کند فرایندها را بیشتر مورد تحلیل قرار دهد زیرا این فرایندها هستند که فرم­ ها را به وجود می ­آورند. هدف پژوهش این است که بر روی فرایندها و علل در محلات تاریخی شهر اصفهان تاکید شود و نگرش فرایند محور به عنوان حلقه مفقوده برنامه­ریزی شهرهای ما مورد توجه ویژه خواهد بود. پژوهش حاضر به روش ترکیبی انجام شده است تا از این طریق از مزایای هر دو روش کیفی و کمی بهره گیریم. در روش تحقیق کیفی، داده ­ها از روش­های مصاحبه، مشاهده و مطالعات کتابخانه ­ای جمع­آوری شده است و در روش تحقیق کمی از آزمون تی  تک نمونه­ای استفاده شده است. نتایج پژوهش نشان می­ دهد فرایندهای جغرافیایی موثر در شکل­ گیری فرم­ها در محلات تاریخی شهر اصفهان عبارتند از: «وجود حیاط مرکزی در مساکن»، «امکان  ارتباط با عناصر طبیعی مانند درخت، آب و نور طبیعی»، «امکان تماشای آیات الهی مانند آسمان، خورشید، ماه و ستارگان»، «اهمیت منابع آبی مانند زاینده­ رود، قنات و مادی­ ها در آفرینش فضاها»، «هماهنگی با اقلیم گرم و خشک»، «اهمیت باغ های خصوصی و خانگی» و «رعایت حریم عناصر طبیعی مانند حریم چاه، قنات، مادی و غیره». از میان  فرایندهای مورد مطالعه نیز «اهمیت منابع آبی مانند زاینده ­رود، قنات و مادی­ ها در آفرینش فضاها» با میانگین 4 بیشترین میانگین را به خود اختصاص داده و مهم ­ترین فرایند موثر در شکل­ گیری فرم­ ها در محلات تاریخی شهر اصفهان می­ باشد.
 
Mrs Elham Zamani, Dr Behshid Hosseini, Dr Hossein Zabihi,
Volume 0, Issue 0 (3-1921)
Abstract

The analysis and evaluation of rural housing texture requires a wide range of effective factors, environmental and ecological factors are one of the important factors. Sub-climates and so on are among the factors affecting the texture of rural housing. In order to understand the environmental factors and the context of a villagechr('39')s mountainous habitat, the need for long distances and precise manual harvesting requires specific difficulties, including distance, time, cost, and ultimately uncertainty. It brings the quality of the final harvest. On the other hand, due to the increasing trend of rural housing development in recent decades and the lack of coordination of new tissues in terms of density with previous ones, it shows the indifference of these housing to the former housing and the environmental context of the villages. Today, new computational and numerical tools in architecture, with the advent of advanced mathematical knowledge in the field of architecture, have brought new dimensions to this field. Will provide. The main purpose of the present study is to investigate the effect of green and dry tissue densities as natural factors on the density of densely populated villages in different climates. This in addition to identifying the density of village textures by emphasizing the comparison of parameters will illuminate new dimensions in the context of village stairs. The simulation analysis tool is a densitometry algorithm based on aerial maps, written by the research authors. The algorithm based on negated aerial maps has the ability to detect natural tissue density in the context of village formation and residential texture. This will reduce the need for physical presence and improve the accuracy of outputs in the analysis of village texture, as well as parameter identification. , The condensation pattern of previous generations into the new generation of housing Will provide a star.

D.r Abas Jahan Abadian, D.r Yaser Kahrazeh, D.r Parviz Reza Mirlotfi,
Volume 0, Issue 0 (3-1921)
Abstract

Factors and stimuli affecting convergence and divergence that play a major role in determining how and the quality of the national coherence is not the same concepts, but variables that have reverse and affected links that identify and analyze their role and effect. It is important to convergence and national coherence, resulting in general security. Regarding this issue, this study was conducted to investigate and analyze the factors and stimuli affecting national convergence and coherence in the southeast of the country. In the same vein, the present article, which is provided in terms of its fundamental purpose and its information, has been providing a response to the question, which has been the most important factor and stimuli on the convergence and coherence of the Baloch people in the southeast. What are the country? The research findings showed that many, different factors affect the convergence, and divergence of the Baloch people in Sistan and Baluchestan province, these factors can be categorized into two groups of internal and external stimuli. The results of the study showed that mutual confidence-determination of people, decentralization and gathering of industries and decision-making centers, strengthening ethnic identity in the direction of national identity, capacity of upstream documents and their role in national cohesion, Baloch and Sistan province And Balochistan with Iran, common social customs, the effective and positive role of the ethnic and national elites of these people and the province can be considered as some of the most important factors and stimuli, and the expansion of the Baloch people in the southeast of the country And the cultural center of the Baloch people in southeastern Iran, regional stress politics, historical economic communications with neighboring countries and the prevalence of today's border markets with the countries of Afghanistan and Pakistan are the most important factors and stimuli affecting convergence and convergence and The national cohesion of the Baloch people is in the province of Sistan and Baluchestan and in the southeast of the country.
 
Hassan Kamran Dastjerdi, Ali Akbar Razavi Hosseinabad, Kyomarth Yazdanpanah,
Volume 0, Issue 0 (3-1921)
Abstract

The country of Iran, with its geopolitical foundations, which is influenced by its geography, has always been the focus of the countries of the world, especially the world powers, throughout history. The use of this capacity and conditions for the economic prosperity of the country depended on the ability of the statesmen and the type and structure of the government systems in formulating foreign policy, and how effective they were in changing the social environment and the way of economic livelihood of the people. In a fundamental and theoretical way, this thesis has analyzed the formulation and presentation of the national strategy of the Islamic Republic of Iran based on its geopolitical characteristics.
The results of this research show that the spirit that governs it according to the structure it entails (statehood), is economic regardless of geographical and geopolitical infrastructure, and this field of foreign policy has not only failed to achieve success, but is also passive. And it has become introspective and stopped from being effective and dynamic. While looking at Iran's geopolitical and geographical foundations, we find that its geopolitical position does not have a global effect and is not below the regional level.
Dr Majid Rasouli,
Volume 0, Issue 0 (3-1921)
Abstract

Iraq is considered the most important part of Iran's foreign policy. For Iranian policymakers, Iraq is a more critical and therefore more sensitive operational theater than other countries where Iran supports local militia groups. History has shown that events in Iraq can have important consequences for Iran's stability. Iraq continues to be a threat to Iran's national security, and that is why Iran seeks to shape Iraq's internal policy and strategic direction. Since 2003, Iran has skillfully infiltrated the Iraqi Shia population by taking advantage of the long common borders and cultural, religious and economic relations with Iraq. Iran's influence is multifaceted and includes access to a wide range of political and social actors. Therefore, this research seeks to investigate the different factors of geoculture in Iran-Iraq relations. To achieve this goal, descriptive-analytical method and Wizard software were used. The findings of the research showed that the divergent factors in geoculture relations between Iran and Iraq were in critical and semi-critical conditions. The robust scenario board consists of 8 different possible situations. Out of these 8 possible situations, 3 are critical, 1 is semi-critical, 1 is static, 2 are semi-optimal, and 1 is optimal. Meanwhile, it should be stated that the majority of Iranian and Iraqi citizens have a common religion, and that is Shia Islam. Hozas or seminaries in the religious cities of Qom in Iran and Najaf in Iraq are centers of Shiite education. However, they were developed under two distinct and competing traditions. Therefore, this factor could be used to improve the situation.
Mis Zakeyeh Aftabi, Phd Morad Kaveyani Rad, ,
Volume 0, Issue 0 (3-1921)
Abstract


 Water is a strategic and rare resource that has been severely limited in recent years due to various national and transnational variables and has severely affected the areas of security, stability, development and prosperity in countries. The high impact of water in the aforementioned areas has placed water at the center of foreign policy and hydropolitical relations of many countries, including South West Asia. In recent years, despite the issue of the water crisis and its role in the relations between Iran and Iraq in scientific, political and media circles, the dimensions of this issue remain unknown and different interpretations have been given. The current research, which is of a research nature and the required inputs were collected in a library method with the aim of obtaining a qualitative understanding of the dimensions and angles of the hydropolitical relations between Iran and Iraq, is based on the fact that, in addition to identifying the content and methodological features, the research gaps To identify the existing in this field with qualitative meta-analysis method. Using the qualitative meta-analysis method, this research has examined 34 researches conducted in the period of 2014-1402 in the form of domestic scientific-research articles, dissertations and articles in prestigious international journals. The results of the research showed that a comprehensive study has not been conducted that has investigated and analyzed the various dimensions of the hydropolitical relations between Iran and Iraq. In this regard, the lack of accurate and real data and the weakness of the theoretical-cognitive foundations of the research are among the shortcomings of the research conducted in the field of relations between the two countries.
Sharifeh Zarei, Dr. Bohloul Alijani, Dr. Zahra Hejazizadeh, Dr. Bakhtiar Mohammadi,
Volume 0, Issue 0 (3-1921)
Abstract

In this research, the most important synoptic patterns of widespread snowfall in the eastern half of Iran have been investigated. For this purpose, the current weather code data and snow depth of synoptic stations in the eastern half of the country during the statistical period of 1371-1400, for the months of October to March, were received from the country's meteorological organization. In order to investigate widespread snowfall, the days when more than 70% of the studied area saw snowfall at the same time were extracted as a widespread day. In order to perform synoptic-dynamic analysis of widespread snowfall in the eastern half of Iran, the classification method using cluster analysis was used and the maps of the representative days including atmospheric temperature, moisture flux, geopotential height, vorticity, front formation, jet stream, omega index and orbital and meridian wind data were drawn. Trend analysis was also performed using the Mann-Kendall test. The results showed that 3 patterns justify the snow cover in the studied area. These patterns are: high pressure in Siberia and central Europe-low pressure in eastern Iran, high pressure in western Iran-low pressure in Sudan, high pressure in central Europe-low pressure in eastern Iran and Afghanistan. In all the patterns in the middle of the atmosphere, the intensification of the meridian currents of the western winds along with the formation of high pressure and low-pressure centers has caused blocking in the path of the western currents and has provided the conditions for the ascent of the air. The concentration of the negative omega field and the relative positive advection, along with the location of the northeastern region of Iran in the left half of the outlet of the Subtropical Jet, have caused severe instabilities and widespread snowfall in the region. Also, the results showed that despite the absence of a trend in the number of snow days in the northeast of Iran, the number of snow days has decreased over time.
 

Firooz Mojarad, Razieh Kheiri, Zahra Noorisameleh,
Volume 14, Issue 35 (3-2015)
Abstract

Iran's Potential for the occurrence of drought at various severities illuminates the need to examine this phenomenon with new indexes. The major deficiency of the current indexes is that they cannot monitor the droughts in daily scale. Effective Drought Index (EDI) overcomes this defect. The goal of this study is to analyze the frequency of daily droughts by EDI in 43 synoptic stations in a 30-year period. Accordingly, the frequency of daily droughts in the stations was calculated by EDI during the seasons and the year. Then the stations were divided into five groups using cluster analysis based on total frequency of mild to most severe droughts (categories 1 to 4), and frequency patterns in each group were examined. The results showed that the most severe droughts have not happened in the stations except for Gorgan, Zanjan and Torbat-Heydariyeh. In contrast, the frequencies of mild, moderate and severe droughts, all being equal, are much more than most severe droughts, and their frequencies are almost equal. In 56 percent of the days, a variety of droughts (mild to most severe) has occurred in the whole country. Based on the output maps, frequency distribution of droughts in the country does not follow a certain geographical pattern, so it could be cocluded that all types of droughts have happened in all regions of the country. However, maximum total frequency of daily droughts (mild to most severe) is observed in the east and center parts. The decrease in the EDI values over time shows the tendency of the most stations towards drought.

Arash Malekian, Mahro Dehbozorgi, Amir Hoshang Ehsani,
Volume 15, Issue 36 (6-2015)
Abstract

Drought is one of the most destructive natural disasters in human societies that cause irreparable impacts on agriculture, environment, society and economics. So, awareness of occurrence of droughts can be effective in reducing losses. In this study, in order to modeling and forecasting drought severity in a 37 year time period (1971-2007) in 21 meteorological stations, located in the cold semi-arid region of north-west Iran, artificial neural networks was used. The input data was annual rainfall data and annual drought precipitation index for all stations that 80% of the data (1971-2000) used for training the network and other 20% (2001-2007) used for testing it and in the next step drought severity predicted for the years 2008 to 2012 by the trained algorithm without using actual and existed data in this period. The appropriate structure for the network, based on Multi Layer Perceptron with three hidden layer, Back Propagation algorithm, Sigmoid transfer function and 10 neurons in middle layer. The results show that the artificial neural networks are well able to predict the non-linear relationship between rainfall and drought as it can simulate drought precipitation index values largely consistent with the real values with more than 97% regression and less than 5% error. So, drought can be predicted by this method in future and also it is useful in water resources management, drought management and climate change. 
Yosouf Ghavidel Rahimi, Manochehr Farajzadeh, Mehdi Alijahan,
Volume 15, Issue 36 (6-2015)
Abstract

Global warming and the meaningful relationship between temperature and precipitation changes over different areas of the earth with temperature increment of the earth, are considered as the most important patterns of this century’s climate changes. Today, there is debate over climate change and global temperatures increasing. Damaging effects of this phenomenon on the planet is one of the most challenging issues in global scale. Because of this, the research ahead is done for the detection of global warming on maximum temperatures, monthly and periodic (hot and cold) as well. For this study, two groups of data, temperature data of 17 synoptic stations and corresponding amounts of data in global temperature anomalies were figured out over 60 years period of time (1951 to 2010). Goals, the Pearson correlation method for detecting relationships between data's, linear and polynomial regression for trend analysis time series data , To illustrate the correlation between the spatial distribution of temperature data with global warming stations nationwide Geostatistical model Finally, non-parametric test for detecting significant temperature change Man - Kendall were used. According to the results impact of global warming on the maximum temperature in the cold months like January, December and November should be much lower, and the highest in spring and summer season in the southern stations such as Abadan, Ahwaz and Shiraz seen. The above process is also evident in periods of hot and cold temperatures and the influence of the stations temperature of the warm period of global warming were higher than cold period and represent an increase in the temperature of the warm period of years. In between, the number of stations as well as Anzali, Urmia and Khorramabad stations in some months had the opposite influence of global warming and seen drop in the maximum temperatures of them. It is also observed in the results obtained from the analysis period. Station's maximum temperature trend change is represents significant in the summer month. Changes trend in the months of July, August and September, is significant that the process is more pronounced in the southern stations. Significant analysis trend changes have been taken in periods (cold and hot) in studied stations indicative of its significance in warm period.
Majid Vazifedoust, Nima Fayaz, Shahab Araghinejad,
Volume 15, Issue 37 (9-2015)
Abstract

Variation of snow cover area (SCA) in small to large scale catchment can be studied using MODIS snow products on daily to montly time step since the year 2000. However, one of the major problems in applying the MODIS snow products is cloud obscuration which limits the utilization of these products. In the current study, variation of SCA was investigated in Karoun basin, western part of Iran, using MODIS 8-day snow cover product (MOD10A2). More over in order to overcome the cloud barrier in application of snow cover products, a simultaneous employment of the images from both MODIS optical sensor and AMSR-E microwave sensor was recommended. Meeting our target, the combination of MODIS and AMSR-E daily images was exercised to accomplish snow cover area in daily interval and afterwards, a comparison was made between the result and those which had been obtained by the sole utilization of either of them while the weather had been either cloudy and not been overcast. Validation of snow cover gained by combined images was additionally compared with the discharge of one of the catchments existing in Karoun basin. The results demonstrate that regardless of the fact that microwave data, featuring a coarse spatial resolution, can penetrate the cloud cover, on average, AMSR-E images approximately show 16% more snow cover in comparison to MODIS images. The results also illustrate that the correlation existing between snow cover rate of AMSR-E and MODIS images during cloudless days, the difference of average snow cover area decreases from 16% to 5%. Moreover, the upshot of validation by the exercise of daily discharge data indicates that by possessing a correlation coefficient of 0.66, the correlation of snow cover and discharge in combined images features a higher accuracy in comparison to MODIS images with a correlation coefficient of 0.55.
Faramarz Khoshakhlagh, Mohammad Amin Heydary,
Volume 15, Issue 37 (9-2015)
Abstract

  Climate control centers in each area are diverse and understanding how they relate to the atmospheric components of the Earth's surface contribute to prediction of climate fluctuations.   In this study, by using Pearson's correlation and multivariate regression in a thirty-year period (1961-2010), the relationship between widespread rainfall anomalies in entire of Iran west with temperature and pressure of atmospheric centers in East and West of Mediterranean Sea in 5 atmospheric levels (SLP, 850, 500 and 300 Hpa) were analyzed and modeled. Based on the results, the correlation of atmospheric control centers in the East and West Mediterranean Sea with anomalies of rainfall in West of Iran is inverse and meaningful in 95% level. In this study, statistical indicators such as temperature differences and standardized  pressure between West and East Mediterranean sea were identified as the most important indicators in relation to changes of rainfall in the study area.   Based on the designed indicators, whenever indicators DT and DH is positive, this means higher temperature and higher atmospheric standardized pressure in the Western parts of Mediterranean sea in compare with its East and therefore the wet spells (Monthly) occur in the study area, and If the above mentioned index is negative, means that the occurrence of drought in West Iran. As for the indicators introduced for lower levels of the atmosphere, especially in the case of temperature, meaningful strong and direct correlation is seen with rainfall abnormalities in entire West of Iran. Modeling provided some indicator for Mediterranean region using multivariate regression that they showed a relatively strong correlation in this regard of the selected components that include the pressure difference in sea level, the temperature difference in 925 and 850 hPa level in the West (Compared to its East) Mediterranean sea. Also check the regression model using real data confirm the accuracy of the relative performance of the model.  
Arash Shrbi, Soheyla Beygi,
Volume 16, Issue 40 (6-2016)
Abstract

Morphotectonic is one of the new reconition methods of tectonic movements and earthquakes knowledge. Study and measurement of landscapes and forms which made by active tectonics are important objects in morphology science. Active tectonic movements have recorded in the morphology of rivers, drainages, alluvial fans and mountain fronts in a region. Research area is located between 55° 30' -57° 00' E and 32° 00' -33° 00' N in Central Iran structural zone. In this paper, we have studied geological map of Abdoughi and processed satellite images, digital elevation model (DEM), geomorphic and morphotectonic indices along the main faults. Also tectonic activities were measured in this area. The results of mountain- front sinuosity (Smf), ratio of valley-floor width to valley height (Vf) and ratio of valley width to valley height (V) indicate respectively: 1/15, 0/94 and 9/88 values. The displacement of the rivers, alluvial fans and triangular facets indicate tectonic activity during Quaternary along the faults. The morphotectonic evidences and seismicity data show which Abdoughi area is an active region.


Yousouf Ghavidel Rahimi, Manochehr Farajzadeh Asl, Solmaz Motalebizad,
Volume 16, Issue 40 (6-2016)
Abstract

This study tries to identify, classify, and analyze synoptic cold wave in North West region of Iran. This study applies standardized (z scores) index of Minimum Temperature in the period of 1951-2010.as such cold waves were classified based on the intensity of occurance. Out of occured cold wave in North West of the coldest identified wave pertaingt each class for synoptic analyzes were selected. This study suggests that the prevailing pressure pattern during the relevant wave indicates high pressure over the earth surface as well as deep trough in upper layer. From the continuing cold standpoint, the role of changing position from pavallel wind in to meridional corresponel to blocking is very offective. Blocking in turn leads to reduction in speed of cold air masses which are originating from higher latitude. They were assouclated with cold waves. More precipitation as so ciated with higher latitude as well as low speed flows will lead to strong and continious waves.


, , ,
Volume 16, Issue 42 (12-2016)
Abstract

An AO is an example of teleconnection pattern in the northern hemisphere’s winter. In this study, the effect of AO on the monthly minimum temperatures in the North-East region of Iran is investigated. The required statistics, including statistics monthly minimum temperatures for 17 synoptic stations of the under study area was provided from Iran Meteorological Organization’s (IRMO). Pearson correlation analysis as the main method used in this study Show an inverse relationship between minimum temperatures and most selected stations and AO index.The results of this study shows that there is a significant relationship between the AO teleconnection pattern and minimum temperatures of north-east of Iran during the cold season of the year. This shows decrease of temperature in positive phase of the AO and rise of temperature is negative phase. In terms of time correlation coefficients were calculated showed a significant negative correlation between the temperature of stations and the AO Among the studied stations, the relationship between the minimum and average monthly temperatures in Birjand and Bojnoord station more than other stations, affected by the AO pattern, has been fluctuated and significant correlation coefficients between the minimum and average temperature of Birjand and Bojnoord Stations with AO has been calculated. The effect of Arctic oscillation on mean temperature of the studied area, north-east of Iran, during the three months, January to march, and ,two months, January to February, is very distinctive against any other periods of time.


, , , ,
Volume 16, Issue 42 (12-2016)
Abstract

In Iran the issue of occurring natural disasters, particularly mesoscale convective systems. They are important on one hand, because of their increasing intimidations and causing damages and on the other hand, because of their increasing abundance, time of duration, and happening. Therefore life cycle, constituton condition and mesoscale convective systems features in west of Iran using satellite and extention area index and thresholds of brightness temperature 221 and 243 K have been studied. After their statistic analysis, based on mesoscale convective system importance, life and daily cycle, behavior parameters, and synoptic conditions of this system life cycle were analysed. Most of the systems have been formed in southeastern Iraq and in western Zagros hillsides. Wile puberty stages (the maturity) and their expandings were increased with the height increase; in turn, declining of the systems began by passing Zagros chain mountains. The system extention area at the system life cycle starting increases with a smooth process; whereas the reduction process of the system extention area at the declining stage was severe and sudden.


Kamal Omidvar, Reza Ebrahimi, Mohammad Kykhsrvy Kayani, Ghasem Lkzashkoor,
Volume 16, Issue 43 (12-2016)
Abstract

The aim of this study was to investigate the effects of global warming on where the slope changes when the monthly temperature in Iranian territory over the coming decades (2050-2015). The simulated temperature dynamic model EH5OM subset Hybrid Models atmospheric circulations (GCM) selection and data model of the Center for Theoretical Physics Salam (Italy) were derived from emission scenarios A1B scenario was chosen given the scenario of 2100 -2001 found that from 2050 to 2015 were used in this study data is then output the data in the fourth edition of the regional climate model (RegCM4) Linux environment was fine scale output data Downscaling model with dimensions of 27/0 * 27 / Degrees latitude is where the dimensions of 30 x 30 km area of ​​approximately cover the average temperature of the matrix deals 13140 2140 * was extracted. Finally, the slope of the average monthly temperature during the period under study by Mann-Kendall slope age and matrix computation in MATLAB software 13140 * 12 respectively. Results show rising temperatures in March and April to June, more than 90% of the country, that it will be spring's warmer. Increasing the temperature in the winter months and spring mountainous parts of the western half of the country is warming the cold regions of Iran. Temperature negative trend in October and November in the northern part of the eastern half of the region's countries could be indicative of colder temperatures in the northern West.



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