دانشگاه فردوسی مشهدجغرافیا و مخاطرات محیطی2322-16822120130522Thermodynamic analysis of heavy rains caused by the phenomenon cut-off low central and South-West of Iran (Case Study: Event precipitation Persian date December 1, 2008)واکاوی ترمودینامیکی بارش های شدید ناشی از پدیده سردچال نواحی مرکزی و جنوب غرب ایران(مطالعه موردی: رخداد بارش 11 آذر 1387)1202616010.22067/geo.v2i1.16881FAکمال امیدواردانشگاه یزدسعید الفتیدانشگاه یزدفریبا اقبالی بابادیدانشگاه یزدخدیجه مرادیدانشگاه اصفهانJournal Article20121112Introduction <br />Occurrence of heavy and rainstorm events is among the characteristics of arid and semi-arid regions all over the world and particularly in Iran which is causing large floods and debris town. How ever, they can be used to supply and store water by controlling and exploiting the run off water floods. Indexes of atmospheric instability are very useful scientific instruments to understand the nature and predict atmospheric hazards of these kinds of precipitations. In this study, one of the heaviest precipitations of south-west and central regions of Iran (1 December 2008) is been for analysing of the studied within the periods at (2008 to2011) effective mechanisms on the occurrence of such precipitations. The main objective of this study is the thermodynamic analysis of the heavy rains in south west religion of Iran . <br />Study Area <br />The study area is located in Central and South- West regions of Iran, including Kerman, Yazd, Fars, Bushehr, Chahar Mahal and Bakhtiari as well as Kohkiluieh and Boyer Ahmad provinces. These areas are affected by climatic systems originated from sudan and red sea areas. <br />Material and Methods <br />The climatic and topographic conditions of the study area were evaluated first. In order to have a fairly complete coverage of Spatial distribution of precipitation over the study area and more detail information, the properties of most synoptic and rain gauge stations were provided.Given that the reason for the heavy rain on December 1st, 2008 was the presence of a low cut off system, heavy precipitation caused by this phenomenon were detected within the last 4 years and the statistics of precipitation rate of the selected dates were obtained from Iran’s meteorological organisation website. the amount of precipitation on December 15/2008, Recorded as the highest amount during the years, there are it has been chosen as a case study for this paper chosen as a case study. In addition, to achieve to a clear vision of the structure of precipitation, the pressure maps of 500 Hpa level and sea level were drown for the day of precipitation in GPADS soft were. Thermodynamic diagrams known as Skew-T were obtained from the website of the University of Wyoming for the selected date. for analysing the amount of instability, 8 indexes of instability (SI, KI, TTI, LI, CAPE, PW, SOI, SWEAT) were used from Shiraz and Ahvaz stations in the study area. Also to show the amount of vorticity, its relative vorticity map was drawn. In addition, specific humidity map and Holf - Moller diagrams were drawn to illustrate the vertical profiles of horizontal advection of specific humidity. <br />Results and Discussion <br />The results carried out using 8 thermodynamic indexes including Skew-T diagram, specific humidity maps, Holf- Moller diagram, relative vorticity map, sea level maps and 500 hPa level indicate that the heavy precipitations somehow depend on the occurrence of vertical convection motions lower than 500 hPa. The results further demonstrated that there has been a quite strong positive floating power in the process of this dominant precipitation .The cause of this strong instability may be falling of cold air from the high latitude and formation a deep trough, separating the main system and turning into a cut - off low. This process has been increased the temperature of air mass than the surrounding environment and causes to up to 500 hPa level. Regarding the considerable rate of humidity and 24.1 and 19.54 mm of precipitable water in the atmosphere of region, the grounds for the condensation and humidity discharge were provided. The investigating relative vorticity of 500 hPa level concerning the studied precipitation shows that the maximum of this quantity during the precipitation has been on the south-west parts of Iran. Furthermore, combining the flows of wind with specific maximum of humidity cores over Sudan and the south of Red Sea has provided the required humidity for the occurrence of such precipitations which have been drawn to the south and southwestern regions of Iran through anticyclone formation over the Saudi Arabia peninsula. <br />Conclusion <br />The results obtained from the instability indexes show that the instability rate has been a considerable factor for the heavy precipitations. The cause of this strong instability can be attributed to the downfall of cold air in lower latitudes, creating a deep trough separated from the main system and turning into a cut - off low. the specific humidity indicates a high humidity amounts during the days with heavy precipitations, map are which is injected on the south west and central areas of Iran through anticyclones located over the Saudi Arabia, Red Sea, Arabian Sea and the Gulf of Adan. The significant amount of relative vorticity is indicated the adjustment of the trough axis with, Its locating in the southern parts of Saudi Arabia and Persian gulf.در این تحقیق یکی از سنگین ترین بارش های نواحی جنوب غرب و مرکز ایران (11/9/87) طی چهار سال اخیر (1387 تا 1390) که دلیل رخداد آن پدیدۀ سردچال بوده است، مورد بررسی قرارگرفته و نیز به واکاوی ترمودینامیکی این بارش های چشمگیر و کم سابقه پرداخته شده است. ابتدا آمار بارش روزهای بارندگی از سازمان هواشناسی اخذ و سپس نقشه پهنه-بندی بارش تهیه گردید. جهت تحلیل ترمودینامیکی این رویداد، با استفاده از 8 شاخص ناپایداری به محاسبه میزان ناپایداری برای دو ایستگاه شاخص شیراز و اهواز اقدام شد. سپس نقشه های سطح دریا، سطح 500 هکتوپاسکال، نقشه نم ویژه، نمودار هاف-مولر و تاوایی نسبی برای روزهای مورد مطالعه ترسیم گردید. نتایج حاصل از محاسبه شاخص ها نشان می دهد میزان ناپایداری در حد قابل توجهی برای ایجاد بارش سنگین بوده است. همچنین نقشه نم ویژه بیانگر آن بود که در روز بارش شدید، نم ویژه از میزان بالایی برخوردار بوده است که از طریق واچرخند مستقر بر روی عربستان، رطوبت دریای سرخ، دریای عرب و خلیج عدن به جنوب غرب و نواحی مرکزی ایران، تزریق و رطوبت این بارش ها را تامین کرده است. میزان قابل توجه تاوایی نسبی نیز حاکی از آن است که موقعیت قرارگیری محور ناوه بر روی خلیج فارس و جنوب عربستان و مقادیر کمیت تاوایی نسبی با یکدیگر منطبق هستند.https://geoeh.um.ac.ir/article_26160_b7d2ba49a27d547afe966255e217a8c0.pdfدانشگاه فردوسی مشهدجغرافیا و مخاطرات محیطی2322-16822120130522Zoning of Cities Level of Vulnerability toEarthquake Danger (Case Study: Tabrizپهنه بندی میزان آسیب پذیری شهرها در مقابل خطر زمین لرزه (نمونه موردی: شهر تبریز)21362617210.22067/geo.v2i1.15617FAابوالفضل قنبریدانشگاه تبرز0000-0001-6225-0433محمد علی سالکی ملکیدانشگاه تبریزمعصومه قاسمیدانشگاه تبریزJournal Article20121126Introduction <br />One of the important problems that most of the metropolitans encounter with is natural disasters. Earthquake is a main natural disaster. Annually 27 sever earthquakes are happened by nineteen thousands killed and twenty six homeless. In recent report of United Nations planning office in 2003, Iran has had the first position in number of earthquakes with severity higher than 5.5 Richter annually and resulted damages and number of killed people. According to the researches of the ministry of dwelling and urban building in national physical plan, fifty percent of the urban residents live in areas with high risks of earthquake. Tabriz is one of the metropolitans of Iran located on region with high probability of earthquake. Adjacency of Tabriz fault and population involving 1378935 individuals and significant industrial cultural and historical capitals introduce Tabriz as a risky zone. So Tabriz fault is the hazardous fault in Iran. Such conditions predict occurrence of human disaster in Tabriz in future. Tabriz earthquake zoning plan conducted by Tehran Padir Company has predicted four hundred twenty six thousands killed in maximum level. According to such earthquake potential, the main goal of this research is identification and zoning of vulnerability in Tabriz in earthquake. <br />Study Area <br />The study area involved Tabriz district. Tabriz is located in North West of Iran and it is Center of east Azerbaijan. This city is the biggest metropolitan of North West by area of 25231 hectare in geographical situation of 46,11,46,23 east longitude and 38, 1,38,9 north latitude by average length of 1340 meter in Tabriz plain. The geographical situation, settlement of city in alleys intersects and mild slopes and economic and human factors and especially political and cultural boundaries, domestic and transit communication roads and neighbourhood of Russia, Turkey and Iraq have been led to outstanding and strategic situation of Tabriz. The mentioned factors have created cross road position in this city. The population of the city was estimated 1378935 in 2006 according to census and dwelling statistics. <br />Material and Methods <br />This research is applied and development and it is descriptive and analytical research. The method is based on analysis and envelopment of information layers in ArcGIS and combination of scale weighting models like AHP and envelopment indicator. At first, by using opinions of experts concerning to earthquake issues like geomorphology, geology, earthquake engineering, urban planning and designing and also previous researches the effective criteria in city vulnerability against earthquake were obtained. According to the comprehensive and systemic approach of this research relative to earthquake, the natural and human made criteria were studied. Finally 15 criteria were selected and each criterion was divided into related criterion based on the analyses. In next step by using data and map provided by road and urban building organisation and municipality and also field study, information layers were prepared in software ARC GIS 9.3 based on the selected criteria. After data analysis they were converted into appropriate RASTER format. Finally by using combination of the layers based on the mentioned models, the final map indicating Tabriz vulnerable zones against earthquake was prepared. <br />Results and Discussion <br />In this research the city was divided into five zones of highest vulnerability, high vulnerability, middle vulnerability, low vulnerability and very low vulnerability. The results of AHP show that most of the north areas except limited areas in west and east with very low population density are in high risk zone. The north marginal quarters and new constructed towns adjacent to fault like Baghmisheh, Roshdiyeh and etc are in risky zone. By distance from north fault the vulnerability level is reduced. Middle parts and some parts of south west and north east are in high risk zone. At the end of south west and west and east part of city the vulnerability is average and by moving toward south east the level of vulnerability is reduced and these parts are in low and very low vulnerability zone. <br /> The results of Overlay Index indicator model are similar to AHP by this difference that frequency of very high vulnerability is less that AHP and most part of the city is located in middle vulnerability zone and most of the city areas are in middle zone. In this model marginal quarters are located in high vulnerable zone and central, economical and historical centers are in high vulnerability zones. <br />Conclusion <br />In a general conclusion and comparison of two models of AHP and Overlay Index, it can be said that Tabriz is not in optimal conditions according to vulnerability against earthquake. Based on statistics of 2006, more than half of Tabriz population lives in very high and high vulnerable zones. In addition most of important land uses and establishments like airport, administrative, political canters, hospitals and historical and cultural monuments are in these zones. It can be referred to development of towns constructed on fault and surrounding areasهدف اصلی این مقاله شناسایی و پهنه بندی محدوده شهر تبریز از نظر میزان آسیب پذیری در مقابل خطر زمین لرزه است. تحقیق حاضر از نظر نوع جز تحقیقات کاربردی- توسعه ای و از نظر روش جز تحقیقات توصیفی- تحلیلی است. در این راستا ابتدا با استفاده از نظریات کارشناسان رشته های مرتبط با زلزله و رویکردی جامع و سیستمی 15 معیار طبیعی و انسان ساخت مؤثر در میزان آسیب پذیری شهر در مقابل خطر زمین لرزه شناسایی شد. سپس با استفاده از توابع تحلیلی نرم افزار AacGIS و مدلهای وزن دهی معیار، تحلیل سلسله مراتبی (AHP) و شاخص همپوشانی (OI) و تلفیق این دو مدل و همپوشانی لایههایی که منتج از معیارهای مؤثر در میزان آسیب پذیری بودهاند، نقشه نهایی پهنه بندی آسیب پذیری شهر در مقابل خطر زمین لرزه بر اساس دو مدل ذکر شده استخراج شد. نتایج دو مدل، شباهت زیادی با هم داشتند؛ با این تفاوت که نواحی با خطر بسیار بالا در مدل تحلیل سلسله مراتبی پراکندگی بیشتری نسبت به مدل شاخص همپوشانی داشته و بیشتر قسمتهای شهر در مدل شاخص همپوشانی در پهنه های خطر متوسط قرار گرفتند. در یک نتیجه گیری کلی میتوان گفت شهر تبریز از نظر خطر زمین لرزه وضعیت مطلوبی نداشته و بیشتر قسمتهای پر تراکم شهری، بخصوص قسمتهای شمالی و مرکزی شهر، در پهنه های آسیب پذیری و خطر بسیار بالا و بالا قرار دارند.https://geoeh.um.ac.ir/article_26172_b0306d5489424e70cbf464379fb120de.pdfدانشگاه فردوسی مشهدجغرافیا و مخاطرات محیطی2322-16822120130522Synoptic Analysis of Khorasan Razavi Droughtsتحلیل همدیدی خشکسالی های استان خراسان رضوی37542619710.22067/geo.v2i1.17464FAعزت نامنیدانشگاه فردوسی مشهدسلیمان صادقیفردوسی مشهدرضا دوستانفردوسی مشهدJournal Article20121204Introduction <br />Drought is one of the climate risks that has made Iran to be one of the 10 countries subject to drought. Scientific knowledge about this phenomenon is necessary in order to plan, manage and confront with problems resulting from drought. Considering the spatial extent and climate variability of Iran, all climates of this country are prone to drought. Due to the fact that Khorasan Razavi province is located in dry and half-dry climate region, and due to frequent droughts in recent years, as well as the dire condition of water resources, this province has been chosen as the studied region. <br />Precipitation less than average annual precipitation and unequal distribution of rainfall in a region is called drought. This natural phenomena roots in inherent variability of climate system and general cycle of weather. Extent and frequency of drought during the time shows distinct patterns , to recognise these patterns is the purpose of this paper. <br />Materials and Methods <br />The objective of this study is to identify synoptic patterns of occurrence of drought in Khorasan Razavi province. For this reason, from all of the synoptic aerology stations in this province, 10 stations from those which had enough statistical data were chosen and for the sake of performing this research, statistical data of precipitation for 9 months of a year up to 2007 has been studied. In order to have statistical analysis of data, we used Excel, SPSS software and SPI index, Also for drawing maps we utilized GIS, Surfer and Grads software. <br />In this study for identifying droughts ,SPI index in a three dry specified months-period was used. Among dry months , pervasive drought in the region 17 drought phenomena was identified in Khorasn razavi. <br />In order to identify synoptical patterns that leads to drought and to reach these patterns for each dry month in different years data of 17 months of high level of geo-potential meter of earth surface and voracity of this period was extracted from NCEP/NCAR site. For recognising and making Matrix ,the area between degree of 10 to 70 northern latitude and degree of -10 to 80 eastern longitude was studied. <br />This matrix consists of 925 cells that for the sake of reducing and coherence of the data, and also for identifying causes of drought, we used principal component analysis. Therefore, for the sake of categorising atmospheric circulation patterns, we got use of S array. Results showed that 5 principal components were covering more than 95 percent of the variance. The first element includes 44 percent of the variance. <br />Table 1: Distribution of total variance and non total variance factors. <br />Elements Variance Total Variance <br />1 44/426 44/426 <br />2 24/186 68/612 <br />3 10/037 78/648 <br />4 9/910 88/559 <br />5 6/730 95/288 <br />Results and Discussion <br />Considering the spatial extent and climate variability of Iran, all climates of this country are prone to drought. Widespread droughts are controlled by four pressure patterns in Khorasan razavi. These main centers which have been identified are as the following: high pressure Subtropical, hood on the Mediterranean Sea, Siberian High-Pressure, North Ridge of the Caspian Sea. <br />Whenever High pressure of subtropical increases especially in cold period of the year, North Atlantic Oscillation (NAO) will occur in positive phase and this high pressure will be stretching towards upper orbit of 38˚. Due to the fact that it encompasses Iran territories such as Khorasan razavi, mild winter with a Trolley weather which creates Virulence air flow in Khorasan Razavi, provides drought in this region. <br /> Findings of this study showed that high-pressure behaviour of subtropical, no formation of west winds' hood on the Mediterranean Sea, as well as formation of Polar Front in Upward circuit has led to air stability and no transfer of humidity to the studied region and has provided suitable conditions for drought to occur in mentioned months. This study can be used to identify atmospheric circulation patterns and to forecast those patterns that help face this climatic event (drought) in a better way. <br />Conclusion <br /> The findings of this research indicated that western wind manner and (North Atlantic Oscillation) NAO performance, no formation of Mediterranean hood and also formation of polar front in high latitude have caused no transportation of humidity and weather stability in study area. When in cold period of the year high pressure Subtropical advances, it increases the temperature of the normal and enhances the humidity capacity to which finally may lead to drought due to decrease in humidityخشکسالی، بارش کمتر از متوسط ریزشهای جوّی سالانه و توزیع ناموزون بارندگی است. این پدیده طبیعی، ریشه در نوسانات اقلیمی وگردش عمومی هوا دارد. بزرگی و فراوانی خشکسالی ها در طول زمان، الگوهای مشخصی را نشان میدهند. هدف این پژوهش، شناخت الگوهای سینوپتیکی رخداد خشکسالی ها در استان خراسان رضوی است. از میان ایستگاههای هواشناسی سینوپتیک استان، ده ایستگاه انتخاب گردید و دادههای بارش 9 ماه از سال تا پایان سال 2007مورد استفاده قرارگرفت. با شاخص SPI دورههای 3 ماهه خشک مشخص شد و از بین ماه های خشک، خشکسالیهای فراگیر در منطقه درمجموع17مورد پدیده خشکسالی تعیین گردید. به منظور شناسایی الگوهای سینوپتیکی دادههای ژئوپتانسیل متر، سطح زمین وتاوایی از سایت NCEP/NCAR استخراج شد و برای ایجاد ماتریس در محدوده بین عرض 10تا 70درجه شمالی و طول 10- تا 80 درجه شرقی مورد استفاده قرار گرفت. به منظور کاهش و انسجام داده ها و مشخص کردن عاملهای خشکسالی از روش تحلیل مؤلفههای اصلی استفاده گردید. تعداد پنج مولفه اصلی، که بیش از 95 درصد کل واریانس داده ها را توجیه کرده، انتخاب شد. یافته ها نشان داد رفتار پرفشار جنب حاره، عدم تشکیل ناوه بادهای غربی بر روی دریای مدیترانه و تشکیل جبهه قطبی در مدار بالا سبب عدم انتقال رطوبت و پایداری هوا در منطقه بوده و شرایط خشکسالی را فراهم کرده است.https://geoeh.um.ac.ir/article_26197_c751eae6f555d052e8f22cd65d25d7cc.pdfدانشگاه فردوسی مشهدجغرافیا و مخاطرات محیطی2322-16822120130522The Effects of Water level Decline on Agriculture of Rural areas around Urumia Lake. Case Study:Northern Marhamatabad County ,Miyandoab Townshipاثرات کاهش سطح آب دریاچه اورمیّه در اقتصاد کشاورزی روستاهای پیرامون55722621310.22067/geo.v2i1.18068FAبهروز محمدی یگانهدانشگاه زنجانمحمد ولائیدانشگاه زنجانمهدی چراغیدانشگاه زنجانJournal Article20121226Introduction <br />One of the most important Environmental hazards that is happening in recent years in Iran is the sudden reduction of water level of Oromiye lake. because of different reasons such as civil Projects, repetitive droughts, an increase in the average temperature in the region, and the resulted inhancement in the evaporation of the lake’s water, it has been susceptible to going dryand has strongly influenced the rural area around the lake, especially the southern parts of the lake. The reduction of the lake's water and the transition of salt to Agricultural landin the region can cause an efficiency fall and even a decrease in the agricultural land and at the end can lead to some serious damages such as the decrease of rural money-making in the region and the province, generating employment, and regression in minor, transferable, and agriculture-dependent industries. Therefore it forces the people of the county to immigrate to cities and causes problems in the cities afterwards. <br /> Being adjacent to Oromiye lake, Rural County of northern Marhamatabad has faced salty agricultural fields and a reduction in the agricultural areas in recent years. Concerning the reduction of the water level of Oromiye lake during recent decades, this research is aimed to investigate the effects of this reduction on rural economy of adjacent rural areas and to find a relationship between the reduction of Oromiye lake's water level and the agricultural economy of rural areas under study. <br /> Study Area <br />Township of Miandoab has been located in the south of Oromiye lake and southeast of Azarbayejan Gharbi province. The area of this township is 2694 square kilometres, its geographical lengths is 46 degrees and 6 minutes of the west and width is 36 degree and 58 minutes to the north of the equator, and exactly in the middle of plains leading to Oromiye lake with the height of 1314 meters from sea level. The governmental parts of this township, according to the statistical results of census in 1385 are County, city, township and rural. Marhamatabad is of the rural County of this township and the district has been divided to northern Marhamatabad and southern Marhamatabad. According to the demographics of Iran's central census bureau, their population in 1385 was 23828. rural County of northern Marhamatabad has been located in the northwest of Miandoab township and includes 8 rural parts. <br />Material and Methods <br /> <br />This is an applied research and from methodological point of view is descriptive and analytical. To collect information literature review and field studies (observation, interview and questionnaire) has been used. The location of this study is rural County of northern Marhamatabad of Miandoab Township and the population under study is the farmers of this rural County. According to the demographic data about agriculture in 1382, the profit-making farmers of the year have been 1437 people out of which 264 were selected as our sample volume based on kokran formula. Choosing households at the level of rural areaways on simple random method so that equal opportunity principle would be considered. Based on this same idea and to reach desirable results, a questionnaire has been designed to investigate economic conditions of rural households of the district from 5 points of view and 37 Reagents relating to economic conditions of agriculture. Then to analyse the gathered information, factor analysis and in a method of analysing the main components has been used. <br />Results and Discussion <br />Of the most important effects of the lake's water reduction in this County that based on results of factor analysis has been incorporated into the analysis as the first factor and has allocated a considerable amount of variance to itself, is the factor of income and Production practices. This is because of the effects of income on the decrease of providing-ability and unit-purchasing capabilities among farmers, and because of a decrease in opportunity and amount of banking system facilities to develop agriculture and the improvement of managing methods of the fields. Second factor that allocated 14.275 percent of the variance to itself is income, facilities and Production practices. One Of it’s most important effects are the decrease of people’s trust on facilities system and the loss of eagerness to use facilities in groups among farmers, the reduction of none agricultural opportunities and the decrease of farmers’ access to farms. The parameter prioritised as the third one is production method, units and income. Some of the included items of this factor is the increase in the costs of use of agricultural machinery and absence of new Production practices that has leaded to a decrease of employment in agriculture. The fourth factor is management and Production practices. in this, advices of Extension Agent on choosing the kind of plants and cultivation has had the most important influence on economic agriculture. <br />Conclusion <br />The Decrease of Oromiye lake's water has had different effects on the development of economic agriculture of northern Marhamatabad rural County (the County of the study). Based on the results of factor analysis , these effects are categorised into eight groups (income and Production practices- income, facilities and Production practices- Production practices, units and income- management and Production practices- income, Production practices and units- units and income- Production practices and income- Production practices) and 80.28 percent of variance has Explained the effects of decrease in Oromiye lake's water level on rural economy of the County. the Results of the research shows that Oromiye lake because of famine, decrease of rainfalls and snowfalls, human factors, and overuse of underground Ground Water, has started to be arid in recent years. Droughts’ extension and the reduction of the lake's water level are serious dangers against farmers which are the biggest source of income for rural people in northwest of Iran. Hurricanes and strong winds gradually transfer salt to agricultural fields in the region and it causes the reduction of cultivation area, rural income, production in the region, generating employment, Lower the boom of industries, transferable industries and agriculture-dependent ones, Salinization of agricultural lands, the destruction of pastures, a decrease in underground water, the destruction of fruit trees and grains and finally the seasonal immigration of rural youth.زلزله، سیل، خشکسالی و کم آبی، آفات طبیعی، آتشفشان، و آتش سوزی جنگل ها را می توان به عنوان مخاطرات محیطی نام برد که دارای اثرات منفی بوده و در آسیب پذیری بخش کشاورزی نقش اساسی ایفا می کنند. از جمله مخاطره محیطی که در ایران در حال رخ دادن است، کاهش آب دریاچه اورمیه در دهههای اخیر است که باعث آسیب پذیری و تخریب بخشی از اراضی کشاورزی در نواحی پیرامون خود شده است. هدف تحقیق حاضر، بررسی اثرات کاهش سطح آب دریاچه اورمیّه در اقتصاد کشاورزی روستاهای دهستان مرحمت آباد شمالی شهرستان میاندوآب می باشد. نوع تحقیق کاربردی، روش تحقیق توصیفی- تحلیلی، روش گردآوری اطلاعات کتابخانه ای و میدانی بوده و جهت تجزیه و تحلیل اطلاعات از تحلیل عاملی و به شیوه تحلیل مولفه های اصلی استفاده شده است. جامعه آماری تحقیق، کشاورزان بهره بردار دهستان مرحمت آباد شمالی بوده است. بنا بر سرشماری عمومی کشاورزی در سال 1382، کشاورزان بهره بردار این دهستان در این سال برابر با 1437 بهره بردار کشاورز بوده که تعداد 264 کشاورز از طریق فرمول کوکران به عنوان حجم نمونه انتخاب شده است. یافته-های تحقیق نشان می دهد، با کاهش سطح آب دریاچه اورمیه و به دنبال آن وزش توفان و بادهای شدید، موجب انتقال نمک به مزارع کشاورزی دهستان شده و این امر کاهش سطح زیرکشت محصولات کشاورزی، کاهش تولید و در نتیجه کاهش درآمد کشاورزان و عدم تنوع شیوه های تولید را به همراه داشته است. همین طور درآمد و شیوه های تولید مهم ترین عامل برای کاهش توانایی تأمین و خرید بموقع نهاده ها و کاهش فرصت و میزان استفاده از اعتبارات بانکی برای توسعه کشاورزی، عدم بهبود شیوه های مدیریت اراضی و قطعات زمین و کاهش اشتغال در بخش کشاورزی در سطح دهستان شناخته شده است.https://geoeh.um.ac.ir/article_26213_89405398e17dfc283bd4a055ad5ce7c2.pdfدانشگاه فردوسی مشهدجغرافیا و مخاطرات محیطی2322-16822120130522Synoptic Analysis of Climatic Hazards in Yasouj Municipality: a case study of an episode of heavy rain on 11th March 2011تحلیل سینوپتیک مخاطرات اقلیمی شهرستان یاسوج، مطالعه موردی: بارش سنگین 20 اسفند 138973902625610.22067/geo.v2i1.18679FAبرومند صلاحیدانشگاه محقق اردبیلی0000-0003-4826-6185مهدی عالی جهاندانشگاه تربیت مدرسJournal Article20130116Introduction <br />Precipitation, an intrinsic part of nature, is essential not only for the survival of human but also for that of plants and animals. Yet, this valuable natural phenomenon can also jeopardise human life, flora and fauna. Torrential rains are sudden events that wreak havoc in Iran and other parts of the world. In recent years, due to man's abuse of nature and disruption of environmental potentials, this phenomenon has become one of the biggest environmental hazards. Yasouj is an area of heavy rainfall in Iran, with semi-heavy and heavy precipitation occurring every year. In this research, an attempt was made to identify the causes of the heavy precipitation in Yasouj on 11th March 2011. The data at 8 isobaric levels 250, 300, 500, 600, 700, 850, 925 & 1000 hPa were analysed. <br />Study area <br />Yasouj is located at the latitude of 30º 28′ N and the longitude of 51º 36′ E from the Prime Meridian. The capital of the Kohgiluyeh and Boyer-Ahmad province in the southwest of Iran, Yasouj is surrounded by the Bashar and Mehrian rivers in the south and west, and the Dena Mountains in the north and east. Yasouj urban areas are located in the high and folded Zagros Mountains. This area is surrounded by steep and complex topography zones. On account of its geographical position, this city has always been exposed to southwest and west air masses, thereby experiencing heavy and semi heavy rainfalls in abundance every year. <br />Materials and Method <br /> the heavy rainfall analysing of Yasouj, data from ground stations as well as from upper atmospheric levels were used. The ground station rainfall data consisted of the daily observations recorded at Yasouj station in the Kohgiluyeh and Boyerahmad province. Data from the atmospheric levels used to analyse the 99.5 mm precipitation of Yasouj were the Geopotential Height, Omega, Zonal Wind, Meridional Wind, Specific Humidity, Relative Humidity and sea level pressure which were obtained from the National Canter for Environmental Prediction website (NCEP) (www.esrl.noaa.gov / psd / data / gridded / data.NCEP reanalysis). <br />Results and Discussion <br />The analysis of the atmospheric maps showed that during this heavy rainfall, intense high pressure developed on West and Central China, North East Pakistan and Siberia. This strong high pressure contrasted with the low pressures on Sudan, South East Asia and Iceland, and the pressure gradient resulted in unstable air. At the upper levels of the atmosphere, Omega-shaped blocking developed on Siberia and with Iran located in the South East of this blocking, the intensity of the instability increased. During the Yasouj heavy rainfall, a huge and thick polar front jet stream was deployed on Iran and the thickness of the atmosphere over the area was significant. At all levels of 500, 600, 700, 850, 925 and 1000 hPa, eddy values were negative, resulting in severe unstable conditions. Vertical movement of air at levels of 500, 600 & 700 hPa in the southern and southwestern parts was negative. This condition resulted in increased convergence and rising air which, coupled with moisture from the Mediterranean Sea, the Red Sea and the Persian Gulf, provided the necessary conditions for heavy rainfall. <br />Conclusion <br />In this research, the heavy rainfall episode of 11th March 2011 in Yasouj was studied from a synoptic and dynamic viewpoint. This heavy rainfall commenced on 10th March 2011 and continued until 14 March 2011, the highest precipitation occurring on 11th March 2011. The findings of this study reveal the strong influence of Sudanese low pressure systems in this heavy rainfall. The findings also indicate that the Mediterranean Sea, the Red Sea and the Persian Gulf were the moisture source regions for this heavy rainfall. This study provides researchers useful information regarding the production of heavy rainfall and its hazards.بارش های سنگین، همه ساله در ایران و جهان خسارت های شدید جانی و مالی را به بار می آورند. پژوهش حاضر، به منظور بررسی سینوپتیک بارش سنگین 5/99 میلی متری یاسوج در روز 20 اسفند سال 1389 به انجام رسیده است. این پژوهش، با دیدگاه محیطی به گردش جوّ صورت گرفته که در آن، ابتدا مقدار بارش رخ داده، توسط ایستگاه های زمینی شناسایی شده و سپس با دریافت داده های سطوح فوقانی جو و تحلیل آنها، علل ریزش این بارش سنگین مشخص گردید. نقشه های مورد استفاده در این پژوهش، نقشه های فشار سطح دریا، ارتفاع ژئوپتانسیل، ضخامت، جت استریم، تاوایی، پیچانه، وزش رطوبتی و امگا بوده اند. تحلیل نقشه های جوّی نشان دادند که در زمان وقوع بارش سنگین مذکور، پرفشارهای قوی بر روی غرب و مرکز چین، شمال شرقی پاکستان و سیبری مستقر شده و با کم فشارهای واقع بر روی سودان، جنوب شرق آسیا و ایسلند شیو شدید پیدا کرده که این اختلاف فشار شدید، باعث ناپایداری هوا شده است. در سطوح فوقانی جوّ، تشکیل یک بلوکینگ امگایی شکل بر روی سیبری و قرار داشتن ایران در جنوب شرق آن که محل حداکثر جریان چرخندی می باشد، بر شدت ناپایداری ها افزوده است. در زمان رخداد بارش سنگین یاسوج، رودباد جبهه قطبی بسیار بزرگی با ضخامت زیاد بر روی ایران استقرار داشته و ضخامت جوّ نیزبر روی منطقه مورد مطالعه، زیاد بوده است. در تمامی ترازهای 500 ،600 ، 700 ، 850 ، 925 و 1000 هکتوپاسکال، مقدار پیچانه نیز منفی بوده که سبب ایجاد شرایط کژ فشاری شدیدی شده است. حرکات قائم هوا در ترازهای 500 ، 600 ، 700 هکتوپاسکال در بخش-های جنوب و جنوب غربی منفی بوده و ضمن تقویت همگرایی و صعود هوا، با تغذیه ی رطوبتی مدیترانه ، دریای سرخ و خلیج فارس، مقدار رطوبت لازم برای تولید بارش سنگین را فراهم نموده است.https://geoeh.um.ac.ir/article_26256_2cf50361f12b028ef5f2b312abdebcc9.pdfدانشگاه فردوسی مشهدجغرافیا و مخاطرات محیطی2322-16822120130522Settlement vulnerability assessment due to land subsidence Geomorphological hazard in part of South Tehranسنجش آسیب پذیری سکونت گاهها و تأسیسات از مخاطره مورفولوژیکی فرونشست در بخشی از جنوب شهر تهران911062629610.22067/geo.v2i1.21020FAمحمد شریفی کیاتربیت مدرسنعمت مال امیریتربیت مدرسسیاوش شایانتربیت مدرسJournal Article20130423Introduction <br />Vulnerability is a logical effect outcome from risk of living over the hazardous regions as well as the resiliency capacity of people for recovers the damages of hazard events. <br /> Vulnerability is a complex phenomenon which can effect and observe in from of environmental, political and c-social-economical vulnerability. <br />According to land subsidence hazard affected over the residential area of south and risk of settlements and infrastructures due to this morphological hazard, the vulnerability appeared as important and necessary task to study area in form of extortion and spatial analysis. <br /> Unfortunately, the wide angle of vulnerability in from of environmental and socio- economical have been effect to the area. It is mainly due to hidden form of hazard (land subsidence) as well as lake of knowledge about this phenomena and ability to manage. Based on this situation of study area, the present study where dell with vulnerability assessment over the settlements and infrastructures in part of south Tehran. <br />Study area <br />This work incorporates investigation of land subsidence vulnerability assessment in part of south Tehran. It is covered an area of 64 Sq km2 between Latitudes 35.3522 N to 35.3939 N and Longitudes 51.1819 E to 51.2292 E. The study area lied in all or part of 17,18,19 and 20th Tehran’s urban areas. <br />Material and Methods <br />The set of several following data set was applied in this study: <br />- Time series of ENVISAT Satellite radar images of ASAR sensor from ESA with time differential of 45-day in period of spring to summer 2011 <br />- Optical satellite images from Landsat TM sensor patch 164 Row 35 on date of 18/07/2010 <br />- The field survey data collected from D-GPS <br />- Documental and reports data as well as library resources <br />In other to extract and measure the rat and area of land subsidence, the set of radar data were analysed for inter fog ram generated using D-InSAR techniques. The outcome map (rat and area of land subsidence) were analysed over the GIS platform to generate risk assessment map and classified it based on pixel involved over the land subsidence hazard area. This map was overlaid with spatial settlement and population maps at last step for vulnerability assessment and analysis. <br />Results and discussion, Conclusion <br />Risk map analysis over the study area was shown that more than 50 percent (57%) of study area lied in low risk area where observed the 12.7 % of area in vary high risk , 14.7% in a high risk and 15.5% in a moderate high risk zone. The result of vulnerability assessment analysis was shown 53 percent of area population and 29 percent of settlement area with high and very high degree of vulnerability. More over nearly of 50 percent of infrastructure include building; highway, metro and road are lied over the valuable area. Furthermore, it is observed that most of area residents include people and government mangers are not inform about risk prone to the area. Which, can increase the social vulnerability and convert the phenomena to disaster.شناخت آسیب پذیری جمعیت و گروه های انسانی به عنوان اقدامی ابزاری در راستای پیشگیری از زایش فاجعه مبتنی بر زیستن در نواحی پر خطر مطرح است. تحلیل آسیب پذیری کانونهای جمعیتی واقع در عرصه های خطر اقدامی علمی برای فراهم سازی زیر ساخت اطلاعاتی مناسب از درجه و میزان خطرپذیری از رخداد مخاطره است. بر اساس چنین دیدگاهی مسئله تحلیل آسیب پذیری ناشی از مخاطرات ژئومورفولوژیک فرونشست در جنوب شهر تهران مورد توجه قرار گرفته است. بدین منظور در ابتدا با استفاده از تکنیک تداخل سنجی راداری نرخ و دامنه فرونشست در محدوده مورد مطالعه استخراج گردید. سپس برای تولید نقشه فضایی عرصه های پر مخاطره نرخ و دامنه فرونشست به عنوان فاکتور عامل در زایش مخاطره به تحلیل گر سیستم در محیط GIS وارد گردید. نقشه خروجی معرف سلولهای واجد ارزش متفاوت از فاکتور زایش مخاطره است. استخراج عرصه متعلق پهنه در معرض مخاطره نشان داد که از مجموع مساحت محدوده 7/12 درصد در پهنه های بسیار پرخطر، 7/14 در عرصه پرخطر،5/15 در عرصه نسبتاً پرخطر بیش از نیمی از محدوده (57درصد) در عرصه نسبتاً کم خطر قرار گرفتهاند. برای ارزیابی میزان خطرپذیری، الگوی توزیع فضایی تأسیسات و ساختوساز های موجود با نقشه عرصه های در معرض خطر هم نهاد گردید. مبتنی بر این اطلاعات و با استفاده از پیمایش میدانی اقدام به بررسی آسیب پذیری جمعیت ،مساکن و تأسیسات موجود در محدوده مورد مطالعه صورت پذیرفت. یافته های تحقیق موید آسیب پذیر بودن اکثر سکونت گاهها و جمعیت ساکن درآنهاو تأسیسات موجود در محدوده میباشد. همچنین بر اساس پایش های میدانی صورت گرفته مشخص گردید که اکثر ساخت و سازهای موجود در منطقه غیر اصولی بوده که این امر باعث فراهم آوری زیرساخت آسیب پذیری برای مستحدثات در شرایط خطرپذیر است.https://geoeh.um.ac.ir/article_26296_0b7e8451b9cd18d91fa6670e079585a1.pdfدانشگاه فردوسی مشهدجغرافیا و مخاطرات محیطی2322-16822120130522Analysis of Environmental and Natural Hazards and Risk Management of Lorestan Provinceتحلیل مدیریت ریسک و بحران مخاطرات محیطی و محیط زیست استان لرستان1071262630010.22067/geo.v2i1.21240FAحسین نگارشدانشگاه سیستان و بلوچستانیاسمن یاریدانشگاه سیستان و بلوچستانJournal Article20130429Introduction <br /> Geographically Risk of an area determines the nature of disasters, their magnitude and spatial distribution. Geographically risk is been controlled by several environmental variables such as geographical situation, climatic characteristics, topography, landform processes, land changing and human impacts. in many countries environmental crises generally is under influences of inability in sustainable development, disturbance of the balance of environment capabilities and development rate. Considering that one of the most important indexes of the countries is the rate of their community's preparedness against various types of natural disasters. In the most of countries is been paid low attention to emergencies and crises among their development plans. development and crisis planners work separately and this led to imbalances in the planning of the development and crisis .Only a few countries have comprehensive plans for risk and disaster management in their development plans which has been given more attention to preparation phase and the most attention is given to phase for coping with crisis. Lorestan geographical location is in the way that it is receptive to diversity of climate, precipitation, temperature, humidity, mountains, plains and etc. In the same ratio the variety of plant and animal habitat is compatible to fertility status. Larestan area is appeared by many environment hazard which is located in a high risk zones in the country. therefore, in this study, environmental and Natural Hazards and risk management are analysed by SOWT technique. For evaluating and managing environmental risks many researchers have tried to study and using different methods. <br />Study Area <br />Lorestan Province, with 28064 square kilometres included 7.1 percent of total area of Iran. This province is one of the western provinces that is located Between 32 ◦40' and 34◦ 23' north latitudes and between 46◦ 50' and 50◦ 01' east longitude? Many years ago Lorestan was the habitat of the people that has been known as Asia Nikos or Aztec from descendants of this grope of people and we can mention Guti and Casey tribes that they have settled in Kordestan, Lorestan and Bakhtiari. <br />Material and Methods <br />Considering the purpose of this study, it is applied-developmental and the research's method of this is descriptive-analytical. For collecting required data and information, library studies and field studies such as interviews, observations, and visits has been done and according to obtained information the environmental and ecological hazards of Lorestan province were analysed. In the next step for data analysing and providing risk management strategies in the next steep SWOT technique was used was used for data analysing and risk management strategies providing. For this purpose the list of strengths, weaknesses, opportunities and threats were identified and according to the four factors of SWOT such as -SO ,-ST ,-WO and -WT were presented. The factors of strengths, weaknesses, opportunities and threats were ranked by authorities and finally with respect to the formation of the strategies by four factors rank of each factor were determined. <br />Result and discussions <br />Table 1: Analysis of Environmental and Natural Hazards and Risk Management of Lorestan Province <br /> <br />External environment Internal environment <br />Opportunities <br />O1. Possibility of using torrents for development of Watershed projects <br />O2. using the environmental standards by managers <br />O3. Promoting the culture of protecting the natural resources <br />O4. Introducing international standards of limit pollutants to officials and managers <br />O5. Possibility of geotourism development <br />O6. Ability to develop and diversify agricultural production according to climate variability <br />O7. Possibility of development and proper utilization of water resources in many areas as a prerequisite for development in all sectors of industry, agriculture and urban <br />O8. Potential of cold water aquaculture development in 7/1501 hectares of plains in the province <br />O9. Preventing migration to outside of the province <br /> Strengths <br />S1. Climate variability <br />S2.Existence water with high quality because of locating upstream of areas <br />S3 .Having plains with high potential for groundwater <br />S4.Existence of all kinds of stone's construction <br />S5. Existence of numerous springs and waterfalls <br />S6. Having a pond and lake <br />S7.Existence of the intact and virginal nature <br />S8 - 768,924 hectares of arable agricultural land resources <br />S9. Progress of seismology and earthquake engineering that enabled man to records the past earthquakes and analyses them accurately <br />S10. Existence of different specific species of plants and animals <br />S11. Special attractions <br />S12. Existence of the vast spaces of greenhouse vegetables and flowers, ornamental and medicinal <br />s13. Existence graduates in various fields of science <br />Threats <br />T1. Risk of the destruction of lakes and wetlands <br />T2. Risk of the destruction of protected areas <br />T3. High seismic potential of province <br />T4. Severe soil erosion <br />T5. Climate fluctuations and the risk of dehydration period <br />T6. Risk of converting the land application to developing physical and non-agricultural one <br />T7. Risk of the destruction of province's glaciers <br />T8. Risk of destruction of the forests, vegetation and genetic reservoirs <br />T9. Reduction of surface water and groundwater caused by factors within and outside of the province <br />T10. Drought and migration to cities <br />T11. Drought and degradation of agricultural land and decrease in diversity of plants and animals. <br />T12. Decrease the role of agriculture in the province's economy. <br />T13. Increase the range of damages of pests diseases and reduction of Rural animal nutrition resources <br />T14. Reduction in quality of agricultural products <br />T15. Infestations a lot of pests and diseases because of the wrong fight against them. <br />T16. Compromising quality of social-physical life of the city because of environmental pollution Weaknesses <br />W1. Existence of many faults in province <br />W2. Existence of eroded areas devoid of vegetation <br />W3. Fight inaccurately and generally rely on chemical methods by the farmers who are beneficiaries <br />W4. Illegal dry farming in the high Dips <br />W5. Distribution of villages of the cities (Noorabad, Selseleh, Boroujerd, Khorramabad, Doroud and Boroujerd) in earthquake-prone areas of Lorestan <br />W6. Changing the natural applications like forests and Grasslands to dry land farm. <br />W7.Grazing too much in grasslands <br />W8. Mountain barriers and lack of continuity of man-made structures and organic relationship between them. <br />W9.Lack of a proper wastewater collection system and its purification <br />W10. Poor distribution of rainfall during the year (the maximum February( the Persian month Esfand) - the lowest in August (the Persian Shahrivar) <br />W11 .Poor quality of installations and equipments in earthquake-prone areas <br />W12. Loss of the proper buildings for controlling the torrents in flood-prone areas of the province <br />W13. Weakness of trees and gardens affected by climatic phenomena (frost and drought) <br />W14. Consuming too much fossil fuels in villages <br />W15. Loss of suitable sites for waste landfills <br />W16. forest fires <br />W17.Destruction of nature by tourists <br />Prioritisation of strategies <br />By comparing internal and external factors in SWOT matrix the acceptable strategies were chosen from the primary strategies. The process of risk management strategies' and environmental hazards crisis prioritization of Lorestan province was performed in two following steps: <br />Step One: Prioritize of the four factors of SWOT (strengths, weaknesses, opportunities and threats) <br />at this stage, the average opinions of the officials about the four factors are considered. The weaknesses with an average of 3.68 are in the first place, strengths with an average of 3.45 are in second place, threats with an average of 3.32 in third place and opportunities with an average of 3.18 are in fourth place. <br />Step Two: Prioritise of the acceptable strategies <br />Strategies and operational priorities determine acceptable strategies to improve risk management and environmental hazards crisis of Lorestan province. Acceptable strategies according to diagram (1) are obtained from combination of four factors. According to this average chart the factors have added together two by two. WT strategies with an average of 7.18 are in the first place, WO strategies with an average of 7.14 are in second place, ST strategies averaging 6.77 are in third place and at last SO strategies averaging 63/6 are in last place. <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br />Figure 1.ranking strategies <br /> <br />Conclusion <br />Analysis of environmental and natural hazards and risk management is the result of the increase in opportunities and reduction of threats. If an opportunity is identified and that opportunity have been used it will become profit and also if the threat have not been avoided it will cause costs. No benefit from the strengths and opportunities of a region achieved automatically and randomly because success depends on good planning and control. The results of the investigation shows that the risks are in terms of the threats and weaknesses of the province but according to strengths and opportunities that facing the province by using an accurate planning and appropriate risk and crisis management and reduce the hazards that caused by threats. In this regard, 17 weakness, 16 threats, 13 strengths and 9 opportunities were identified that weaknesses and threats are environmental and biological risks, the strengths and the opportunities are for moderating the threats and weaknesses and according to the SWOT matrix, 17 aggressive strategies, 12 contingency strategies, 13 adaptive strategies and 8 defensive strategies were presented and according to the officials of the province the strategies ranked as follow: <br />WT strategies with an average of 7.18 are in the first place, WO strategies with an average of 7.14 are in second place, ST strategies averaging 6.77 are in third place and at last SO strategies averaging 63/6 are in last place.مدیریت در حوادث غیر منتظره با محور دانایی ترکیبی از علم و هنر و عمل است و برنامه ریزی ابزاری است که ما را از وضعیت موجود به وضعیت مطلوب می رساند. لذا اولین قدم برای برنامه ریزی صحیح تبیین و شناخت وضعیت موجود می باشد که نیاز به واقع بینی دارد تا خوشبینی، آنچه که امروزه بعنوان مخاطرات طبیعی از آن یاد می شود در برنامه ریزی استان لرستان در کنار توانمندیها جای میگیرد، عموماً نتیجه عملکرد نادرست و ارتباط نامتعادل انسان با طبیعت است، از این رو به کمک مطالعات کتابخانه ای و مشاهدات میدانی مخاطرات محیطی و زیستی در سطح استان شناسایی شد و با بهر ه گیری از تکنیک SOWT نقاط ضعف ، نقاط قوت، تهدیدات و فرصتهای مخاطرات در قالب ماتریس SOWT طراحی شد و با نظرسنجی از 30 نفر از مسئولین عوامل و استراتژیها رتبه بندی شد. با ترکیب عوامل چهارگانه در تولید استراتژیهای (ST،SO،WT،WO)، استراتژیها بدین شکل رتبه بندی شدند: استراتژیهای WTبا میانگین 18/7در رتبه اول، استراتژیهای WOبا میانگین 04/7 در رتبه دوم، استراتژیهای ST با میانگین 77/6 در رتبه سوم و استراتژیهای SO با میانگین 63/6 در رتبه چهارم قرار دارند. نتایج این تحقیق را می توان در مدیریت ریسک و بحران مخاطرات محیطی و زیستی مورد استفاده قرار داد.https://geoeh.um.ac.ir/article_26300_9feafb90d0e17d77efccc5bb65370ad0.pdfدانشگاه فردوسی مشهدجغرافیا و مخاطرات محیطی2322-16822120130522Evaluation of seismic vulnerability spectrum of cities based on various intensity scenarios using µd, TOPSIS, and GIS Models (Case study of Yazd)ارزیابی طیف آسیب پذیری لرزه ای در شهرها بر اساس سناریوهای شدت مختلف با استفاده از مدل هایµd ، TOPSIS و GIS (نمونة موردی شهر یزد)1271422631710.22067/geo.v2i1.21220FAسعید ملکیشهید چمران اهواز0000-0001-6884-4259الیاس مودتدانشگاه شهید چمران اهواز0000-0002-0837-1223Journal Article20130429Introduction <br />Vulnerability is a term used to show the amount and extent of damage and the losses caused by natural disasters in different communities (social, formal-physical, etc.). Vulnerabilities is identified as the sensitivity of the environment against the hazards. From among natural disasters, earthquakes can have a vast scope of losses for desert regions. Therefore, in order to reduce and prevent further damage, it is necessary to study its different aspects. The present study which is a developmental-practical using descriptive-analytic method examines the issue in Yazd. Since the seismic predictions based on statistical methods can provide satisfactory results, this study uses quantitative models µd, TOPSIS and GIS models, and Excel and SPSS Software to address the problem. Also, in order to reduce the error rate and to provide more accurate forecasts, 50 social-formal indicators variables were involved in the analysis and evaluation of data. The results of the µd model show that building damage from the earthquakes of up to 5 Merkali almost have no or very little damage. However, if earthquake intensity is more than 7 on the Richter scale, more than 50% of buildings are earthquake-vulnerable in the zone 2. And in the TOPSIS model, Social Vulnerability average in districts 0.412% which zone 2 and 1 with respective TOPSIS of 0.642 and 0.183 had the highest and lowest social vulnerability against earthquake in Yazd. <br /> Earthquakes have long been among the most dangerous natural disasters and always have the highest risks. Earthquake risk is the expected loss through which environmental damages are incurred to the society and environment. In other words, risk is a combination of danger and vulnerability; and since vulnerability may be as diverse as human, functional, social, financial vulnerability or a combination of these, to estimate the risk requires a comprehensive approach. Accordingly, the present research by focusing on the vulnerability of the city against earthquake and using statistical and quantitive models investigate the issue to help organisations involved in preventing and controlling social and natural disasters have the ability to reduce and manage such possible dangers. <br />Material and Methods <br /> This study is a developmental-practical investigation. It employs combination of descriptive, documentary and analytic documents. Statistical population comprises 50 neighbourhoods in 3 districts of Yazd. 50 variables, including social-physical indicators have been used utilising quantitative and statistical models to rank seismic vulnerability of the districts. <br />Study Area <br /> Yazd with geographic coordinates 54 degrees, 22 minutes east longitude and 31 degrees, 53 minutes north latitude is the largest historical unit and the administrative Center in the province of Yazd. The average altitude of the city is 1230 meters above sea level. The population growth in Yazd has always been faster than other areas of the province. This has made the population be more than other townships and the whole province. In a single 60 year period (1946-2006), the population grew from 63502 to 194000. <br /> Within the city there is only one known fault. 3 km North East of Yazd, there are deposits of marl and chalk and salt Neogene sandstones and conglomerates with northwest-southeast orientation along the fault. The fault is 47 km of pressure kind. Located in the central position of Iran's regional tectonic, it inherits most tectonic features of other sites. <br />Geographical location of the area has made the region one of the focal points of tectonic activity one the one hand, and various tectonic quakes with various severity of erosion and sedimentation processes on the other hand. <br />Results and Discussion <br /> According to the logic of TOPSIS Model provided calculations, district 2 had the second lowest distance with the positive ideal and the maximum distance with the negative ideal. And district one had the farthest distance to the positive ideal and the lowest distance with the negative ideal. <br /> According to the model which determines the average seismic injuries and damage: <br /> District 2 with the highest density of 50% and district 3 with 32% have the lowest population density. Therefore, for this indicator, district 2 is the most vulnerable in terms of social damage. In the case of the socially vulnerable earthquake zone, the area between the city of Yazd. <br /> In low-risk group that is group aged less than 14 years, district 3 with 29% had the highest and district 1 with the lowest rate, about 23%, had the lowest risk. <br /> Regarding road network vulnerability index, district 2 with about 46and district 1 with 18%, had the maximum and minimum vulnerability, respectively. <br /> In addition, building damage in the earthquake of up to 5 Merkali had almost no or very little damage. However, if earthquake intensity is more than 7 on the Richter scale, more than 50% of buildings are earthquake-vulnerable in the zone 2. And in the TOPSIS model, Social Vulnerability average in districts 0.412% which zone 2 and 1 with respective TOPSIS of 0.642 and 0.183 had the highest and lowest social vulnerability against earthquake in Yazd. <br /> Conclusion <br /> Due to the necessity of the issue and regarding the conducted investigations, it was determined that structural damage in the earthquake of up to 5 Merkali are almost no or very little. And even if reached to a seismic intensity of 6 Merkali only about two percent of district 2 are damaged. However, if earthquake intensity is more than 7 on the Richter scale, more than 50% of buildings are earthquake-vulnerable in the zone 2. Therefore, this area of the city has the highest vulnerability to earthquakes. Also Structural damage is district 3 is less than 40% and less than 20% in district one. Statistically, the obtained TOPSIS in the district 1 is 0.183%, in district 2 is 0.642%, and in district 3 is 0.411%. Thus, district 1 and 2 in Yazd are the most vulnerable and the most resistant, respectively, against earthquake in terms of social damage.آسیب پذیری اصطلاحی است جهت نشان دادن میزان و وسعت آسیب و خساراتی که در اثر سوانح طبیعی به جوامع در ابعاد مختلف(اجتماعی، کالبدی-فیزیکی و غیره) وارد آمده است. بنابراین میزان حساسیت محیط در مقابل سوانح، آسیب پذیری آنرا مشخص می کند. در بین سوانح طبیعی زلزله می تواند دامنة وسیعی از خسارات را به خصوص برای مناطق کویری داشته باشد. بنابراین جهت هرجه بیشتر کاهش و جلوگیری از خسارات آن نیازمند مطالعه و بررسی در ابعاد متفاوت می باشد. پژوهش حاضر با ماهیت توسعه ای- کاربردی و روش توصیفی- تحلیلی به بررسی موضوع در شهر یزد پرداخته است. و از آنجا که پیش بینی لرزه ای بر پایه روش های آماری می تواند نتایج قابل قبولی ارائه دهد؛ این پژوهش با بهره گیری از مدل های کمی ، TOPSIS و GIS، نرم افزارهای Excel و SPSS به بررسی موضوع پرداخته است. همچنین به منظور کاهش ضریب خطا و تعیین دقیق تر پیش بینی ها، 50 متغیر از شاخص های اجتماعی-کالبدی در تجزیه و تحلیل ها دخیل و مورد ارزیابی قرار داده است. نتایج حاصل از مدل نشان می دهد خسارت ساختمانی در اثر زلزله تا شدت 5 مرکالی تقریباً آسیبی ندارند و یا خیلی ناچیز است. اما اگر میزان شدت زلزله بیشتر از 7 ریشتر باشد بیش از 50 درصد ساختمان های منطقه 2 در معرض آسیب زلزله قرار دارند. و در مدل TOPSIS میانگین آسیب پذیری اجتماعی در مناطق برابر 412/0 درصد بوده که منطقه 2 و 1 به ترتیب با میزان TOPSIS، 642/0 و 183/0 درصد بیشترین و کمترین آسیب پذیری اجتماعی شهر را در در برابر زلزله در مناطق شهر یزد دارا می باشند.https://geoeh.um.ac.ir/article_26317_423b8e971b4527119177867ee2a7d863.pdf