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Mesysam Jamali, Ebrahim Moghimi, Zeynolabedin Jafarpour, Parviz Kardovani,
Volume 2, Issue 3 (10-2015)
Abstract

The process of urbanization and development in high-risk areas such as river banks has increased the vulnerability of urban communities to environmental hazards. The banks of Khoshk River in Shiraz is one of these areas. These hazards are two parts : hazards resulted from river and waterways erosion (destruction, transportation and sedimentation) and the hazards resulted from floodings over the surrounding urban areas.

In order to prepare the literature review for this study, the various books, theses and articles were applied. Also, in order to determine the spatial position of this section, the Satellite Images and Google Earth pictures were used. The Global Positioning System (GPS) was also applied for the field observations such as collecting spatial data, extracting the kind of formations, Geological structures and faults. ArcGIS and Global Mapper 16.2 were also used for data processing and mapping.

 The geomorphological hazards in Khoshk River bank were evaluated in two parts:

  1. The evaluation and analysis of the role of river and flooding processes in creating the environmental hazards for Shiraz.
  2. The evaluation and analysis of the role of humans as the intensive factors of riverine and floods hazards in city.

 The evaluation of longitudinal profile in the river indicates that when the stream is entered to plain, the water moves with more speed because of faults and high steepness over the  Drake alluvial fan. One indication of this process is the presence of coarse sands and angled gravels. In this part, the erosion of riverbank is much higher than the erosion of river bed. In this section, the longitudinal profile of the river has a regular trend of concave and convex sections due to the erosion in convex parts and sedimentation in concave parts. In addition, there is a balance between deposition and digging process. The erosion is very intensive in regions where arc meander is close to  the flooding plain of the bank and causing the destruction of all facilities.

 The longitudinal profile in the river indicates that the height and slope of river has been reduced from North West to Maharloo River. The average slope of the river is 2.40%.

         In order to determine the role of flooding in creating risks for Shiraz, the floodwater discharge data were collected from Regional Water Organization. Furthermore, in order to understand the role of maximum discharge values, various experimental relations were used in the basin. The un- ordered development of urban areas especially in the north west, destruction of natural areas intensified the amount of  runoff and reduction of vegetation cover.

 The pick values of maximum discharges in Khoshk river  with the return periods of 50 and 100 years waere estimated 115m3/s to 131.4m3/s respectively which may result in overflowing of water on the streets. The human factors include the construction of bridges on the river, fencing river with stones and construction of beach, construction of bypasses for public transportation and reducing the traffic in the riverbed and trespassing to the river bed in Shiraz caused the overflowing of water from the river. The last floods in Shiraz occurred in 1987 and 2002 that caused major losses to the houses and commercial places close to Khoshk River. In order to analyze parts of river that are close to the town and have more important influences on the hazards and disasters, the satellite images of khoshk river basin in the town were taken and the river was classified in three sections with regard to risks level, river morphology and river classification based on its hazards for close areas as high risk (Maali abad Bridge limits to Fazilat Bridge and Sardkhaneh Bridge to Maharloo River), low risk(Tange sorkh to Maali abad Bridge) and medium risk (Fazilat Bridge to Sardkhaneh Bridge).


Abdolhamid Nazari, Hossein Sadin, Ogholgol Khorrami,
Volume 2, Issue 3 (10-2015)
Abstract

Vulnerability to natural hazards is one of the most important issues of villages in Iran. Iran is listed in the first ten accident-prone countries in the world. It annually imposes many damages on villages through natural disasters such as earthquakes, floods, etc. To tackle the problem, an important attempt was applied during the recent decades is the policy of resettlement. The mentioned policy has been followed in forms of movement, integration and aggregation of villages. As spatial foundation and location of settlements are mostly based on natural environmental factors, then before any attempt, or before any dislocation of the villages, ecological potential of the new place needs to be evaluated. However, as dislocations resulted from unpredicted events such as flood are associated with emergency conditions and would be done very quickly; there is not enough time for evaluation before the action. In result, conducting such plans, unlike their positive impacts on service-delivery, cannot be quite welcomed due to ignoring the ecological and environmental factors which need to be considered before any actions. Therefore, such plans can create some negative consequences and be considered as non-successful plans.

       One of the projects that have been implemented in connection with this issue in Golestan province is dislocating and integrating flooded villages on Kalaleh County during 2001 to 2006. Based on the mentioned plan, twelve villages which were located at higher section of Gorgan Roud and were aggregated and located at a new site named “PishKamar”. These villages were flood-damaged. Such a site was urgently constructed based on a top-down approach, urban-based patterns and without considering the needs and ideas of stakeholders. So, such a plan needs to be evaluated and assessed against some normal and standard criteria. As such mistakes can be repeated elsewhere, recognizing the pros and cons of such plans would be a good guide and experience for the next projects. The present paper aims to evaluate the ecological potential, physical design of the site as well as measuring the levels of PishKamar site resident’s satisfaction.

      This study is a kind of the ex-post facto evaluation and its methodology is descriptive – analytical. To do that, we have considered a four-steps ecological potential of the site using Makhdom’s model. We also have used the 1:50000 topography maps, 1:250000 geological maps, 1:100000 land-use maps and 1:100000 soil fertility and capacity. All layers were transferred into ArcGIS environment, for more analysis. Data collection was based on surveying, interview and questionnaire. The statistical sample include 1350 households heads resided at the studied site, of them 200 persons were randomly selected for data collection purposes(According to Cochran AWT IMAGE  in the formula, standard deviation was 36%, test statistical was 1.96 and α was equal to 0.05). The results of the first stage of our study indicated that based on 330 primary integrated cells and overlaying the maps, there would exist 13 homogenous ecological units. In addition, a significant proportion of the Makhdom indicators used to assess indices was confirmed by chi-square test. Accordingly, 67% of cells in class I with good ecological potential and 8/28% of the cells in the appropriate ecological class II and only 2.4 percent were in class 3 to be inappropriate ecologically. Thus, of total 13 units, 11 units with an area equivalent to 127 hectares were classified as class I and II, and environmental units with an area of three hectares in third class were inappropriate. Therefore, the studied site was evaluated as a good site in terms of ecological conditions.

     In addition, evaluation of residents' satisfaction mapping site in terms of compliance with the ecological conditions and the physical texture design which was based on systemic approach of sustainable development indicators was revealed that the maximum satisfaction of residents was related to house orientation and strength of buildings, road network design and architecture patterns.But the dimensions of environmental issues including soil resistance as a result of landslides, climate harmony with the architecture and the wind direction has not completely been considered. Totally, of 11 evaluated criteria, people were satisfied with 6 of them and disappointed with another 5 criteria. It was confirmed by T-test.


Ali Shammaii, دانشگاه خوارزمی تهران , ,
Volume 2, Issue 3 (10-2015)
Abstract

Human and social crisis and natural hazards are of great importance and urgency in urban development planning. As a result, in order to reduce the loss of life and financial damages, one of the necessities of urban planning and spatial analysis is identification of vulnerable areas. In Piranshahr city due to its sensitive geographical location and zoning the implementation of passive defense in urban planning is of utmost importance. The importance of this study is to examine vulnerabilities in order to operate an optimal crisis management. The main objectives of the study are:

- Identifying the most vulnerable neighborhoods of the city.

- Identification of vulnerable facilities and equipments.

The research method is descriptive - analytical and research space is Piranshahr city limits. In order to identify the characteristics and distribution of facilities and equipment in the border town Piranshahr library and field methods have been used. The results of the last census (1390) of Statistical Center of Iran, observation and interviews with local people and experts was used. The master plan and detailed studies of 1391 and relevant maps of the municipalities, the aggregation and dispersion of urban facilities and equipments were used. To value the passive defense importance in the city sixteen vulnerability variables were defined and measured according to opinions of people and experts. Then the data were analyised with the  Delphi software. The main variables include: Lifeline, crisis management centers, military bases, equipment and support centers. After determining the rating of each factor and sub-sectors, by using AHP and Expert Choice software vulnerability of each of the following criteria were calculated. For mapping the city Piranshahr fuzzy model is used.

The results showed that the variables of vital artery with coefficient of (0.469), crisis management centers and joint support centers with coefficient (0.201), municipal equipment by a factor of (0.086) and military centers coefficient (0.043) are among the most vulnerable facilities and equipments in Piranshahr city. The neighborhood of western, central and south-west of the city, including the Kohneh-Khaneh and Grow of a cultural1 neighborhoods, Ghods, Isargaran, Zrgtn and Mom-Khalil, were the most vulnerable neighborhoods in the city regarding the military attacks. Spatial analysis of vulnerability of the city resulted in three vulnerability regions. The neighborhoods of the West, Central and South West (Kohneh-Khaneh and Grove neighborhoods and part of a cultural1 neighborhoods, Ghods, Isargaran, Zrgtn and Mom-Khalil) are the most vulnerable neighborhoods of the city. The reason for this situation are the physical characteristics of the city such as texture, organic, fine texture and high density residential units, existence of urban infrastructure, core founding of the city (the Kohneh-Khaneh neighborhood) and the secondary core (Zrgtn neighborhood). whereas the neighborhood (Park City and part of Koy-e-Khayyam and new neighborhoods of Mohammadkhan in the north and the south and southeast of the city) due to the preparations made for the perfect skeletal indices as well as the extent of large open spaces are somewhat immune and safe regarding the passive defense.

Keywords: Spatial analysis, vulnerability, Passive defense, city of Piranshahr.


Mahmood Khosravi, Samad Fotohi, Soliman Pirouzzadeh,
Volume 2, Issue 4 (1-2016)
Abstract

Iran is among 10 top potential countries of occurrence of natural hazards in the world and from among 35 natural hazards, so far about 30 hazards have occurred in Iran(Negaresh and Latifi,2009). One of the different types of natural hazards which every year causes a lot of damage particularly in arid and arid regions of the world is the existence of sandy hills(Omidwar,2006); sandy hills are mostly created in coastal regions of most seas and oceans. These hills are the result of mutual effects of waves, marine currents, wind and sediments available in coastal regions. They are implemented with components of the coastal environment and construct the eco-systemic bases in which there are valuable collection flora and fauna(Kidd, 2001). The studied region is among the deserts near Gulf of Oman coasts. Sand on the coast are with marine origins and by getting far from the sea, sandy hills, in addition to having marine origins, have land origins. In some seasons of the year, particularly in summers and falls in which Monsoon winds start blowing up, the range of the movement of running sands is more towards rural regions in such a way that annually, a large part of sands covers residential areas, farmlands, road & building facilities, and infrastructural facilities in the rural areas of the west of Zarabad and left behind heavy damages and losses. The aim of this study is the detection of temporal-spatial changes in sand dunes in the Gulf of Oman coastal region. In addition, trend and severity of this hazard and the effects of climatic and environmental factors that intensified dimensions of risk were considered.

The present study, to achieve the mentioned objective is an applied study and in terms of research, a method is a descriptive-analytical one. To collected data, it uses library-documentary as well as survey studies in the rural areas of the west of Zarabad. After that, to investigate the changes of the degree of displacement in dunes of the studied region in the 23 year time period (1991-2014), GPS and the Enhance Thematic Mapper Plus (ETM+) images of the Landsat Satellite 7 and 8 with the spatial resolution of 15 and 30 m were used. The satellite images were used in this study with time intervals of 10 and 13 years were related to years of 1991, 2001, and 2014 in August respectively and they were extracted from USGS.The ENVI software and Geographic Information System were used for images processing and interpretation. The geometric and radiometric corrections were applied on images according to standard procedures. Finally, classification and related calculation were performed.

The conducted studies in the region based on the interpretation of satellite images and survey studies indicated that changes in the available users in the region, the top increases for dunes occurred in 1991 as 561.25 km2, in 2001 as 568.10 km2, and in 2014 as 575.45 km2. In fact, it has experienced a growth as 17.198 km2. The vegetation whose area covers 32 km2 in 1991, in 2014 has reached an area with 45km2 and increased as 1.6% compared to the previous period. In 1990 to 2014, the area of the user which has been changed in favor of dunes, includes 0.108 km2 vegetation, 10.60 km2 stream sediment, and 264.35 km2 arid lands. Therefore, dunes move with high speed after each storm and during these displacements, a lot of damages are imposed on farmlands, facilities, and rural settlements. Investigating the degree of imposed damages indicates that annually, a large area of regions such as villages, roads, and facilities are influenced by running sands, which this trend can cover more regions in future years. The degree of displacement of dunes, according to the analyses conducted during the research period(1990-2014), has been so great that it has caused the burial of a large number of villages, infrastructure, farmland and roads and resulted in the unemployment of a large number of farmers in the region. Imposed damages to rural settlements have not been less than agricultural sectors and facilities. Therefore, due to the movement of running sands during recent years, 15 villages have been at the exposure of damages in such a way that compensation of these damages has imposed heavy costs, and consumed a lot of time on the shoulder of the society. As a result, the movement of dunes towards studied villages, i.e. Biahi, Mashkouhi, Abd, Rig Mostafa, Kalirak, Kerti, and Gati which are in the coastal regions, and Sohraki, Ganjak, Tanban, Zahrikar, and Kaidar which are located at far distances from the coast suffer from the highest amount of dunes and are considered as the most critical regions in terms of the movement of sand dunes. The results also showed that the important factors on severity and development of these critical regions are: a shortage of precipitation , loose and fine-grained sediments, low slope, no obstructions against the marine winds and high frequencies of winds and storms in this region.On the other hand, the lack of any varieties of vegetation on dunes, as well as the drought of recent years confirms spatial-temporal changes in the sand dunes towards the study area.

In this research, the hazards due to running sands in the West region of Zarabad (Baluchestan) were studied. The results from satellite image interpretation and field works were showed that the greatest change of land cover in recent years was related to sand hills. The total areas of sand dunes in 1990 are 561 km²,in 2001 these area increases to 568 km² and finally in 2014 reached to 578.5 km².The average growth rate is about 0.76 km² per year. The  landcover change from river sediments and barren land to sand dunes, during this period are estimated 10 and 264 km².

The storm and marine winds moving  sand dunes and running sands from coastal regions to rural settlements,farmland,Roads and other Infrastructures of the region. This hazard was just too much damage like  buried villages, the destruction of roads and unemployment and migration of farmers. The number of evacuated villages are 15 cases that some of these villages is located in the coastal region(Biahi,Mashkohi,Abd,Kalirak……..) and others in inland(Soharaki,Ganjak,Tanbalan,…..).

This is the manifestation of crisis and instability in the rural communities that creating important obstacles to development and it is triggered vulnerable rural development was decreased.


Homa Dorostkar Gol Khili, Yadollah Yousefi, Mehdi Ramezanzadeh Lasboyee, Hematollah Roradeh ,
Volume 2, Issue 4 (1-2016)
Abstract

Natural disasters is one of the main challenges for developing countries, which not only cause death and emotional pain and suffering of survivors, but greatly affecting development. Reduction programs and prevention of disasters, including policies that countries to increase community capacity in disaster, are followed to improve the effects of these disasters. One of the risks that affect Iran, is flooding. Iran has a very high risk of flooding, which in most years, about 70% of annual credit plan is paied to reduce the effects of natural disasters. Floods in recent years has left a lot of damage in many parts of Iran. Because the flood event and can not be prevented, but we can assess the resiliency and vulnerability of risks to reduce the effects of flooding greatly. Planning in disaster management process can reduce the risks of accidents and improve the resilience. Thus, how and by what means we can increase the capacity of society to accept a certain level of risk is very important. In recent years, many researches, focused over concept of resilience and disaster risk reduction policy. This research study area is the Nekarud basin in Mazandaran province. Population growth and unethical uses of Nekarud and natural resources, humans and their facilities, infrastructure and natural resources of the basin are vulnerable. The aim of this study was to evaluate the resiliency and identify strengths and weaknesses in the flood affected villages Nekarud margin is based on random sampling of villages (8 villages) have been affected by floods in recent years, were selected. The research method is descriptive and analytical study of its nature. The aforementioned villages to assess the resilience, the four dimensions of economic, social, and institutional infrastructure based on the location of the axis (DROP) provided by Cutter and his colleagues in 2008, was used. According to the surveys and the results obtained, it can be stated that the model DROP, because of the location-based (geographic), and the integrity of the elections aspects and indicators to measure and assess the resilience of settlements is a good model. The dimensions considered to measure resilience include: economic, social, institutional and infrastructure. After determining the dimensions required components and indicators research, scientific references were identified by the study, questionnaires were prepared. Secondly, the need of the rural sample in the form of a questionnaire, collected and analyzed after coding in SPSS. The findings of the study showed that the settlements are in a different situation in terms of resilience in different dimensions. The economic resilience for the total sample is 8.96. The amount of this variable for Zarandin-e Olya, Zarandin-e Sofla, Abelo and Kuhsarkadeh rural settlements is higher than the average whole.


Amir Hossien Halabian, Fereshteh Hossienalipour Jazi,
Volume 2, Issue 4 (1-2016)
Abstract

We can identify the flood not only considering circulation pattern in occurring day but also by studying circulation pattern a few days before fresh event. This subject has mutual approach. In one hand, it indicates  that circulation patterns which were before flood event have important role in determining the conditions and moisture content of studied area and playing the fundamental role in few coefficient of region because it determines the previous moisture. On the other hand, it indicates that we should tracking the rain-genesis synoptic systems from source to end place of their activity for studying floods and their meteorology factors which have created them. By this way, we can acquire more comprehensive recognition about the relationship between circulation pattern and floods. In the other words, the identification of synoptic patterns that have created the flood reveals not only the mechanism of their emergence but also is useful for prognosis and encountering with them. The extensive researches have been accomplished about Inundation in the world and Iran, but Iran haven’t much antiquity about synoptic researches. For foreign researches, we can name researchers such as Hireschboeck (1987), Kutiel et al(1996), Komusce and et al (1998), Krichak  and et al (2000), Rohli and et al (2001), Kahana (2002), Teruyuki Kato(2004), Ziv and et al (2005), Carlalima and et al (2009). The numerous researchers have studied the Inundation climatology in internal of country such as Bagheri (1373), Ghayour (1373), Kaviani and Hojatizadeh (1380), Moradi (1380), moradi (1383), Mofidy (1383), Masoodian (1384), Masoodian (1384), Hejazizadeh et al(1386), Parandeh Khozani and Lashkari (1389). In this research, we considered the heavy precipitation of Azar 1391 in southwestern of Iran that resulted in flood phenomenon in the cause and effect manner so that can do necessary prevention actions before occurring the flood for preventing the probable damages and optimal use of precipitations by forecasting the patterns that have created the flood.

In this synoptic study, we need to two database: one group is variables and atmospheric data consisting of geopotential height of 500 hpa level (in meter geopotential), zonal wind and meridional wind (in m/s) and special humidity (in gr/kg) during this times 00:00, 06:00, 12:00 and 18:00 Greenwich in 0-80° northern and 0-120° eastern with local resolution of 2.5*2.5 Arc that have been borrowed from database of (NCEP/NCAR) dependent to National Atmosphere and Oceanography Institute of USA, and other group is daily precipitation data of region rain gauge stations during 4-8th Azar of 1391 (24th November – 28th November 2012). In continuation. By applying the environment- circulation approach, we took action to drawing circulation pattern maps of 500 hpa level, thickness of atmosphere patterns of 500-1000 hpa and moisture flux convergence function from 4-8th Azar of 1391 (that for calendar, conform with 48 hours before beginning the showery precipitation until ending the storm activity) by using data which obtained from database of NCEP/NCAR and the synoptic conditions of above flood have been studied and interpreted in the region.

Flood is one of the most destructive natural hazards that have imposed and impose many damages to people during the history. Hence, the final aim of this research is to explain the key interactions between atmosphere and surface environment and in other words exploration of the relationship between circulation patterns leading to the flood generating precipitation in the southwestern of Iran for forecasting the time and intensity of showers occurrence that lead to flood. For this purpose, by applying environmental-circulation approach, the circulation patterns identified and studied which resulted in flood generating precipitation. The result of this research indicated that torrential precipitations in the region have formed the deep trough in days 4-8 of Azar on the east of Mediterranean and the studied region placed in the east half of this trough that is the location of atmosphere instability. At same time, thickness patterns, indicate the flux of cold air from northern Europe to lower latitudes and spreading the warm air of north of Africa to latitude 50° northern. As a result we expected the frontal discontinuity in the encountering place of these two air mass. Analysis of the moisture flux convergence patterns also indicated that torrential precipitations were the result of moisture flux from Mediterranean and Persian Gulf; and Red Sea and Arab Sea taken into account as reinforced sources.


Hassan Afrakhteh,
Volume 2, Issue 4 (1-2016)
Abstract

The City-region of Tehran is encountered with various environmental problems, including traffic, air pollution, lack of drinking water and green space, physical texture conflict, flood and earthquake. Capital accumulation has considerable role in shaping spaces which can create and intensify environmental disaster in special socio-economic situation. The second cycle is the conversion of capital to fixed and long-term assets with the aim of further benefits, which in fact produces two types of artificially environment during this process namely the built environment for production, and the built environment for consumption.

The third cycle is aiming to connect science to production and increase production capacity by investment in science and technology. When production of surplus value reduced in the first cycle, surplus value of second cycle increases through speculation and real estate transaction (real estate capital). Therefore, the owners of the lands and buildings are encouraged in production, trade and supply of these type assets.

In the courtiers that are legally and administratively encounter with tax receipt problems,  urban lands ownership is deposited to market system without any control, hosing transaction continues without any limitation, situation is moving forward to personal vested interests, asset value rises rather than production value, the price of land and construction increase severely. In the above mentioned condition, beneficiaries attempt convert the natural resources including park, mountain, river privacy and road privacy to marketable commodity and legally or quasi legally seize them. Therefore, unreasonable construction and population density increases and city-region will encounter with environmental disasters.  

The main objective of this research is to understand the underlying factors of capital accumulation through construction and its impacts on createion and intensification of environmental disasters in the Tehran city-region.

  Five different regions of Tehran were selected for data collection. "Q-methodology" was used for gathering and analyzing data. The society of communication or people whom the study sought to identify their mentality towards the research topic, were 25 experts selected through purposive sampling. To set the concourse of communication, a combination of primary (experts commented in an interview) and secondary (sources of credit) sources have been used and   34 statements have been developed. After sorting the data for analysis, SPSS software data matrix is ​​formed. Factor analysis, as main method of analyzing Q data matrix has been used based on Q logical methodology.

The results of Q analysis depicted four viewpoints with variance of 95.911 percent on the underlying cause of capital accumulation through construction and its contribution on increasing risk of natural hazards in Tehran city-region.

The first viewpoint has devoted 52.800 percent of total variances and can be titled as" Function of real estate transaction and Non-productive economic domination".

The second viewpoint which has received 18.914 percent of total variances is accordance with "commodification of land and housing". The third viewpoint is" management and monitoring of the city-region space" with 15.163 percent of total variances.  The fourth viewpoints under the title of" monitoring and control of natural resources" has assigned 9.034 percent of total variances.

As result of these processes, land and housing business have weakened society's productive capacity by extensive land use change in the urban peripheral area's due to its huge and quick profit. The above process accompany with selling excess density policy created a powerful political and economic stratum which harmed city sustainable development. The mountainous area of north, north east and west of Tehran, have annexed to metropolis as a result of above mentioned regulation and  may gardens have converted to construction by different gropes and institutions.

Q method analysis depicted that the Tehran City-Region has converted from use value to exchange value. It means that values of the city including work, security, education, leisure and welfare have been lost in favor of exchange value. In other words, the city has been converted to a commodity for exchange and selling in pursuit of profit, rising cost of urban land, building and housing. Consequently, the city-region construction site is extended to the river beds, steep slops and surrounding natural environment. This in turn is leading to rapid land use change and violation of environmental and spatial rules and regulations and intensification of environmental hazards.


Tahereh Soltani Gord Faramarzi, Abbas Mofedi, Amir Gandomkar,
Volume 2, Issue 4 (1-2016)
Abstract

For a synoptic analysis of high polluted days in 13 and 14 November 2007, a combinatorial synoptic analysis was used. From methodology prospect, the present study has utilized the "circular environment" synoptic approach and with respect to the restrictions on very high-polluted days in Mashhad city, the subjective synoptic analysis used for data processing and analyzing the prevailing atmospheric conditions.

In the present research, four sets of the data, including the pollution data recorded at the stations monitoring air pollution, digital atmospheric data, data of upper air stations and the outputs of HYSPLIT model were utilized. The data on air pollution obtained from the Department of Environment Protection of Khorasan Razavi were related to Wahdat station located in the center of Mashhad city. The pollutants include CO, NO2, SO2, ozone, and particulate matter (PM10(  prepared and processed on a daily scale for a 7-year statistical period (2005-2012). When studying the quality of air pollution over Mashhad city, it is necessary to indicate that Mashhad city had only one station monitoring air pollution (Wahdat station) until 2010 and unfortunately, out of 10 present stations for monitoring the air pollution, only Wahdat station was involved a suitable statistical period duration to be studied. Accordingly, the present study has been conducted only by using the pollution data recorded in Wahdat station and utilizing the data of other stations ignored due to the shortness of statistical period duration. The reanalyzed data of the National Centers for Atmospheric Prediction (NCEP) and the National Center for Atmospheric Research (NCAR) with a horizontal separation 2.5 × 2.5 were used in order to study the atmospheric conditions. The atmospheric conditions include the sea level pressure, geo-potential height, vertical velocity, and orbit wind (u) & meridian wind (v) components on different atmospheric levels from the past 48 hours and in a 6-hour interval. In addition, upper air data about Mashhad station (Mashhad airport) were used on a similar period. Upper air data have been obtained from the website of Wyoming university (http://weather.uwyo.edu/upperair/sounding.html) on under study days, including air temperature,  dew point, direction, wind intensity and the atmospheric stability and instability conditions (based on Skew-T Curves – logP). These data are only available on Zero Greenwich hour. The outputs of the HYSPLIT model were also used as complementary data for tracing particulate matter in days 10 -15 in November. In this study, the HYSPLIT model, version 4.9 was used. In the present research, the role of regional atmospheric circulation and pressure patterns were investigated on a synoptic scale in very high-polluted days in November 2007 in Mashhad metropolitan. For this purpose, the mechanism dominated on occurring a very high-polluted period in this city was analyzed using a combinatorial method based on synoptic and thermodynamic analyses as well as tracing particulate matter. The results of studies involve the following findings: the days 13 and 14 November 2007 (22 and 23 Aban, 1386) show the highest concentration rates among the polluted days in Mashhad city. The findings of the research show that the synoptic pattern dominated the very high polluted period (13 and 14 November 2007) is a migrant high-pressure pattern. Accordingly, it may be concluded that the incidence of serious pollutions in Mashhad is initially the result of interacting local conditions with air circulation on a regional scale and then the other local factors. In the other words, Mashhad city would experience very high-polluted days only when regional atmospheric circulation provides suitable conditions to increase the concentration of pollutants. What is obvious is that in the winter season the serious pollutions occurred in Mashhad city are mainly as the results of prevailing extra-tropical systems (migrant anticyclone). Studying subjective synoptic analysis, tracing the backtracking of particulate matter and the atmospheric thermodynamic conditions ( combinatorial synoptic analysis) have provided a deeper and more accurate understanding of the conditions prevailing in the occurrence of serious pollutions in the northeast of Iran. Studying the output of the HYSPLIT model indicates that the migrant stack system of western wave together with the subtropical stack would control the air circulation pattern on the northeast of Iran in 13 and 14 November 2007. Tracing the particulates shows an anticyclone system on the zone. Also, studying SKEW-T Curves related to the migrant high-pressure pattern revealed a different structure, so that the day 12 November 2007 faced with a radiation inversion along with an increased temperature, but on day 13 November 2007 an inversion from the sort of subsidence between the interval of level 850 to 700 hpa was appeared and also reached to higher than 700 hpa.


Gelaleh Molodi, Asadolah Khorani, Abbas Moradi,
Volume 3, Issue 1 (4-2016)
Abstract

Climate change is one of the most significant threats facing the world today. One of the most important consequences of climate change is increasing frequency of climate hazards, mainly heat waves. This phenomena has a robust impacts on human and other ecosystems. The aim of this study is investigating changes of heat waves in historical (1980-2014) and projected (2040-2074) data in northern cost of Persian Gulf.

The focus here is on Mean daily maximum temperature and Fujibe index to extract heat waves. For this purpose 6 weather stations locating in north coast of Persian Gulf, Iran, are used (table 1).

Table1: weather stations

Station

Latitude

Longitude

Elevation(m)

Abadan

30° 22' N

48° 20' E

6.6

Boushehr

28° 55' N

50° 55' E

9

Bandarabbas

27° 15' N

56° 15' E

9.8

Bandarlengeh

26° 35' N

54° 58' E

22.7

Kish

26° 54' N

53° 54' E

30

  In addition, 4 model ensemble outputs from the Coupled Model Intercomparison Project Phase 5 (CMIP5) are used to project future occurrence and severity of heat waves (2040 to 2070), under Representative Concentration Pathways 8.5 (RCP8.5), adopted by the Intergovernmental Panel on Climate Change for its Fifth Assessment Report (AR5) (table 2).

Table2: List of the AR5 CMIP5 Used Models

Model

Modeling Cener

Country

CanESM2

Canadian Earth System Model

Canada

MPI-ESM-MR

Max-Planck-Institut für Meteorologie

Germany

CSIRO-Mk3-6-0

Commonwealth Scientific and Industrial Research Organization

Australia

CMCC-CESM        

CMCC Carbon Earth System Model

Italy

The output of models is downscaled using artificial neural network method (ANN). A feed-forward network of multi-layer perceptron with an input layer, a hidden layer and an output layer is used for this purpose. 73 percent (1980 – 2000) of the data is used for training and 27 percent (2000-2005) for testing ANN models. Root Mean Square Error (RMSE) is used as an indicator of the accuracy of Models.

RMSE=AWT IMAGE

Here  AWT IMAGE is the outputs of ANN models (downscaled data) and AWT IMAGEis the observation data.

Fujibe et all (2007) used an index based on Normalized Thermal Deviation (NTD) for extracting long-term changes of temperature extremes and day to day variability using following equations:

AWT IMAGE

Where N is the number of days in the summation except missing values. Then nine-day running average was applied three times in order to filter out day-to-day irregularities.

AWT IMAGE=(i,j,n)=T(i,j,n)-T(I,j)

The departure from the climatic mean is given by

AWT IMAGE=AWT IMAGE

AWT IMAGE

If NTD >2 and at least lasts for 2 days it determine as a heat wave.

Results

Table 3 shows the results of downscaling selected GCM models.

nodes

RMSE

Average RMSE

Sigmoid function

Linear function

Abadan

Bushehr

Bandarabbas

Bandar-e-Lengeh

Kish

CanESM2

5

1

9.6

6.1

4.85

4.7

4.5

5.97

MPI-ESM-MR

5

1

9.3

7.1

3.9

5

4.3

5.9

CSIRO-MK3-6-0

15

1

8.8

5.6

3.6

3.4

3.6

5

CMCC-CESM

10

1

9.2

5.8

3.9

4.7

3.9

5.5

Table 4 compares the frequency of heat waves for GCMs and historical data.

CanESM2

MPI-ESM-MR

CSIRO-Mk3-6-0

CMCC-CESM

Historical data

Abadan

434

401

448

387

430

Bushehr

376

423

420

406

407

Bandarabbas

441

405

457

382

410

Bandar-e-Lengeh

380

414

388

401

400

Kish

421

442

415

442

399

For historical data, heat waves are more frequent in Abadan station than other stations. There is an increasing trend in the occurrence of heat waves in historical data and monthly frequency of heat waves show the highest amounts for summer.

For both historical and future data 2 days listening heat waves are more frequent.

Table 5 shows seasonal changes of heat waves for historical data and GCMs.

season

The ratio of heat waves from total historical data (percent)

The ratio of heat waves from total projected data (percent)

Abadan

Spring

30.43

24.02

Summer

29.19

27.87

Autumn

17.39

22.61

Winter

22.98

25.48

Bushehr

Spring

21.42

24.23

Summer

25

26.21

Autumn

28.57

24.82

Winter

24

25.32

Bandarabbas

Spring

21.73

24.7

Summer

26.81

27.01

Autumn

25.81

25.17

Winter

24.1

24.63

Bandar-e-Lengeh

Spring

23.55

23.74

Summer

23.33

29.82

Autumn

23.74

25.81

Winter

25.17

20.8

Kish

Spring

24.27

24.8

Summer

25.53      

28.32

Autumn

23.35

25.21

Winter

23.1

23.8

In recent years the frequency of heat waves is increasing in all studied stations. Coincide with Russia and Europe, the highest amounts of heat waves is occurred in 2010 in northern coast of Persian Gulf and this is adopted Esmaeilnezhad et all (2013), Gavidel (2015) and Azizi (2011).


Hadi Soltani Fard, Ahmad Zanganeh, Marzih Nodeh, Farzanehsadat Hossini,
Volume 3, Issue 1 (4-2016)
Abstract

As an important factor to be considered, rapid population growth, lack of resources and appropriate management has led the natural hazards threatening human societies increasingly. Although it is impossible to eliminate the effects of natural hazards, however, risk reduction and risk cities against natural phenomena has become the main topics of urban planning and design in recent years. Iran is one of the countries that are faced with numerous natural hazards. With Location and geographical characteristics, Iran is a main country located in earthquake belt; therefore earthquake is one of the main natural hazards in human settlements. Now, more than 70 percentage of Iran are at risk of earthquake. This study investigated spatial effects of urban roads and network on vulnerability in Amirieh neighborhoods. The aim of this study, identification and isolation of factors affecting the vulnerability of urban streets and quantify the effect of each factor is the vulnerability. Amirieh neighborhood with 10 (he) area, located in center of Sabzevar city. Amirieh is part of the detorated urban fabric in Sabzevar, therefore, earthquakes it is one of the main threats of this urban historic neighborhood. As a holistic approach, safety and immunization of the city is in regard with the recognition of constituent elements of urban structure completely. Comprehensive identification is aimed at reducing the vulnerability of urban and urban elements. In order to, one of the most important elements is the road network and impacts on the vulnerability of urban neighborhoods. Neighborhood is smallest unit of urban spatial planning that has the most important role in the planning and reduction at the risks of natural hazards. The spatial relationships between the components of an urban system that can fit through association with the whole city would be reduced environmental hazards, particularly earthquakes.-From planning perspective, any activity be organized in small-scale and size, will increase the possibility of its constituent elements in crisis management. The vulnerability of urban networks in related to spatial structure and impact on other infrastructure directly. The nature of the vulnerability of urban streets can be based on three factors: the structure, origin and traffic. As a structure, form and pattern of urban access associated with the vulnerability that this pattern is in related to urban network movement geometry and topological properties. Road network and access can be analyzed spatially by both composition and configuration. Composition of road network affected by the physical geometry and presented in different scales and defined by location, form, length, angle and direction. While the configuration is sets of the points witch defined by the related lines. Roads determine accessibility to critical points, and are including topological features, displacement, time travel or transport costs.

In analysis process of data and maps, scientific methods and models were used such as geographic information systems (GIS), the Analytic Hierarchy Process and method (AHP) and weighted overlaying map. Research method involves the following steps:

  1. Introduction of indicators: In order to determine the vulnerability of the network in the various aspects needed to be based on the criteria established to determine the vulnerability and damaging. In this study, selected Indicators include: Type of road, the width of road, construction quality, density, population density and age of the buildings.
  2. To determines the importance and ranking criteria: Each of the above criteria has the sub-criteria which based on expert opinions, and comparing them with field studies. The (AHP) was used to weight sub-criteria for the experts and paired comparison.
  3. To weight the criteria: At this stage, the selection criteria are weighted by research. To determine weights, the criteria and sub-criteria, were quantified by which is determined measure the intensity excellence criterion of i to j. At this step, the above criteria and sub-criteria in the form of a questionnaire was given weight by the Group of Experts. Then, weights of each criterion was determined the final weight by Expert Choice software.
  4. Layers integration and production of Vulnerability final map: in order to produce the final map of vulnerability, the command Raster Calculator and weighted overlap method was used in the GIS environment. Density calculation is one of the suitable methods of spatial analysis. we calculated the density to represent the value of points or lines in the form of levels. In this study was used Kernel density equation for converting line to surface value, due to represent of spatial value. Map applying numerical value to each pixel density is formed in the periphery.

In Amirieh neighborhood, Results show that width of streets, land use, population density, quality of construction and age of building will be in the range of medium to high vulnerability. In this study, 50% of the length of passages, more than 73 percent of the quality of the existing structure, 69% of land uses, and more than 40 percent of population density were classified in the range of high to very high vulnerability. The final vulnerability map shows that more than 58% of the total area is in the range of high and very high vulnerability. The areas with moderate vulnerability involve 19 percent of the entire neighborhood approximately. The final map shows that areas with low vulnerability appropriate width placed adjacent to the passages open while the passages the end and low width are critical zone of significant congestion. Too, the results showed that the topological characteristics of the network involved in the formation of critical points. So that in the event of a crisis and then could impair relief and evacuation of the neighborhood. From spatial perspective, vulnerability is influenced by two urban network properties:

  1. Urban network structure: The street network is determined based on geometric features. This communication and spatial distribution of the points and roads in the neighborhood.
  2. Spatial hierarchy: Spatial hierarchy access to the neighborhood of the important points is that the crisis could guarantee public services.

Mostafa Karampour, Mohammad Saligheh, Meysam Toulabi Nejad, Zahra Zarei Choghabaki,
Volume 3, Issue 1 (4-2016)
Abstract

In issues related to air pollution, the thickness of the boundary layer is known as the depth of the mixed layer because the pollution on the ground surface is mixed in this entire layer through turbulence processes. In most cases, the boundary of the area is clearly visible on big industrial cities. The depth of the mixed layer has an important effect in the concentration of air pollution which is dependent on the intensity and duration of solar radiation and wind speed. Usually after 2 to 3 hours from the time of maximum solar radiation, air temperature near the earth's surface reaches its maximum value. At this time convection of heat is formed in the air near the earth surface and transfers the heat from the surface to higher altitudes. These vertical movements will cause atmospheric turbulence and increase in instability. This is when the growth of the mixed layer reaches to its highest level. After sunset, night temperature inversion occurs near the surface. This temperature inversion is due to the rapid cooling of the Earth's surface. In such condition, the cold air layer is near the earth's surface and the warm air layer sits on top of it and air is in a stable condition.  As a result, the accumulation of contamination, if there are sources of pollutants, will increase in the earth's near-surface layer. If the conditions remain steady during the day, the mixed layer will not have much growth and as a result, contamination in the shallow layer near the surface of the Earth reduces solar radiation.

Each year, thousands of gaseous pollutants and particulate matter are emitted in the metropolitan area of Tehran and due to the geographical and climatic conditions of Tehran, temperature inversion phenomenon is not something unexpected. By formation of the inversion layer, these pollutants will remain near the earth's surface for a long time which in turn will be the cause of a lot of heart and respiratory problems. Therefore, identifying the characteristics of this layer on polluted days is of particular importance to the health of the residents of this city.

In this research, the study area is Tehran which is in the foothills of the southern Alborz and between longitudes 51 ° 2 'to 51 degrees 36' east and latitude 35 degrees 34 minutes and 35 degrees 50 minutes northern. The height of the northernmost point of this city is 1800 and up to 1200 meters in the center and 1050 meters in the south.

To conduct this research, inversion data including temperature, wind, atmospheric pressure and humidity and vertical navigation radiosonde data at the Mehrabad weather station from January to 29 December 2013, were taken from the Meteorological Organization of country. Then the statistics of daily vertical scroll of atmosphere above the Mehrabad synoptic station was received from the University of Wyoming. Also, the hourly data of air pollutants including gaseous pollutants CO, N2O, O3, SO2 and particulate matter (PM10) were prepared from the air quality control center (AQCC) for the stations Aghdasiyeh, Geophysics, Poonak, Rey and District 11.

After receiving information about the vertical scroll of the atmosphere in Mehrabad station, in order to have a closer examination of the vertical profiles of potential temperature changes in the lower atmosphere, using daily data from the radiosonde to obtain potential temperature changes in height were measured. Then, in order to identify the days with high pollution levels (the unhealthy condition for sensitive groups) and days with good conditions, so that all stations under study were the same, based on a standard index of air pollution Table 1 was developed. In the end, 4 days with critical inversion of potential temperature, including two polluted days (February 6th and August 16th) and two clean days (9 February and 5 June) were detected. Then according to the proposed method of Hefter, the approximate height of the boundary layer was calculated for these 4 days.

In this study, it was observed that the boundary layer height in contaminated cold season of the year reached 1,200 meters in the morning hours while in the afternoon in the cold samples, it grew to 1900 meters. In the warmer months based on the height of critical inversion layer in the selected days it reached more than 6,000 meters. In pure samples of warm and cold seasons, the boundary layer height had significant growth to the extent that in the cold sample of the year it reached to 2,100 meters in the morning and 2,600 meters in the afternoon. On June 5, which is intended to represent the clean and pure heating season, boundary layer height was of 5300 meters in the morning hours which shows a 4,000-meters increase in comparison to its polluted counterpart. The point to be noted is that since the active track of potential temperature can be considered as a measure of air stability, in the critical inversion, for the case of polluted samples of morning hours that were irradiated with inversion, active track of the potential temperature was very high in them. Thus on days with radiated inversion (polluted days) we can say that border of boundary layer was based on the inverted layer. Also the methods used in these types of inversions are more efficient for the determining height of the boundary layer.


Nasim Hossien Hamzeh, Ebrahim Fattahi, Mjtaba Zoljodi, Parvin Ghaforian, Abbas Ranjbar,
Volume 3, Issue 1 (4-2016)
Abstract

Dust particles consist of important aerosols and resulting in blowing strong winds on the surface of desert areas. These particles enter the atmosphere under the influence of different factors including: weather condition (wind, precipitation and temperature), land surface (topography, humidity level, roughness and vegetation), soil features (texture, density, composition and land use (agriculture).

Today powerful dust storm destroys people lives and causes severe damages to their life and also causes financial problems in most regions of the world especially in west and southwest of Asia. Dust storm is one of the most important natural phenomena and also a kind of severe natural disaster that influence Iran and its west and southwest part. The location of Iran on the desert belt is accompanied by frequent increasing of sand and dust storm. Integral prediction of dust storm phenomena can be useful in decreasing damages caused by these storms. So synoptic-dynamic analysis of dust storms and their simulation play an important role in achieving to this goal.

In this research, we investigate severe dust storm in August 2005 that affected a large area of our country. Select of dusty days were based on minimum visibility and maximum durability of that dust storm. At first, we show the minimum of daily visibility table. These data has been provided by Meteorological Organization in 5 western cities. The synoptic maps were related to these phenomena derived from NOAA website and synoptic and dynamic interpretation has been done. We have got the data with resolution of 2.5 degree from NOAA website.

Then 700 hpa relative vorticity maps were drawn. We investigate MODIS images instrument on Aqua satellite and evaluate the amount of mass concentration of dust particles. Then the Lagrangian Integrated Trajectory Model has been used to determine the backward trajectory of dust particles. We run HYSPLIT model by GDAS data with a resolution of 0.5 degrees. At last we investigate the output of the WRE-CHEM model. This model was run to simulate dust storms in 7-10 August and FNL data with a resolution 1 degree use for initial and boundary conditions. WRF-CHEM is used to simulate dust condition and transmission. As a part of WRF model, its main application is the study of atmosphere chemistry.

At 500 hpa a very strong ridge entered Iran from the southwest. It covered all areas of our country which prevents the transference of dust to high levels of atmosphere. In 700 hpa relative vorticity maps show one day before dust storm reach to Iran a Positive voriticity is located in Iraq and Syria. So dust comes up to higher levels of the atmosphere and in dusty days in our country. There is a negative voriticity located in our country and because of downside movement of the air, dust storm happen in Iran.

Dust loading and friction velocity of outputs of the model has been drawn in dusty days. The time series of dust concentration of output models for Tabriz are compared with the concentration data of Environmental Organization of visibility data. Result show that a low pressure system is located over the Oman sea that its blaze has been extended to the northwest of Iran. On the other hand a high pressure center is located in the Europe that extended to the east of Mediterranean. So strong pressure gradient were in Iraq and Syria and they caused the creation of strong winds in their deserts which caused dust emission.

Friction velocity related to the model outputs show that the velocity of wind is high in dusty days in Iraq and Syria. So conditions are suitable for dust raining. Satellite images showed that WRF/CHEM model is simulated very well in emission, source, diffusion and the extent of the areas covered with dust. Comparing MP10 concentration of the model output with and Environment Organization data of Tabriz city show that WRF/CHEM model forecast daily changes well. But model underestimate significantly in quantity of concentration. This error may be due to a model considering only dust quantity but other pollutants affected on visibility. In general it can be said that in this event, dust concentration has been underestimated by WRF/CHEM model especially in maximum amount of PM10 concentration.


Mehdi Mohammadi Sarin Dizaj, Mohsen Ahadnejad Roshti,
Volume 3, Issue 1 (4-2016)
Abstract

Iran, due to its geographical location and its human and environmental characteristics including those at risk of natural hazards there. In the area northwestern Iran, Zanjan city in three dangerous fault ,Zanjan in the north, fault Soltanieh in south and Byatlar located in West And based on a hazard map for earthquake country, prepared by the International Institute of Earthquake Engineering and Seismology as well as Based on Earthquake Resistant Design of Buildings (Regulations 2800) prepared by the Research Center, Department of Housing and Urban Development and Urban Country, the relative risk of high-grade is zone. A major part of the Physical structures of Zanjan in recent decades regardless of the strength and stability of the regulations, such as Regulations 2800 is applied.On the other hand the lack of required data, including geometric and non-geometric data of the infrastructure and buildings in the city Such as the problems that have not been noted. Accordingly, this study examines the relationship between resilience Zanjan city's Against Earthquake And indicators and factors affecting resilience Physical and infrastructure to identify And will evaluate the resiliency Physical and infrastructure in the city of the study.

The results of scientific and experimental studies in the field of natural hazards and the head of the earthquake, in the last few decades shows That the best way to deal with these risks, is be more resilient settlement in different dimensions. Settlements in risk reduction approach, resilient system that can temporarily or permanently absorb risks And with conditions changing rapidly, adapted without losing its function.

In this study, the analysis and evaluation; the region and evaluation criteria include Quality building, types of structures building, Old building, facade building, building density,  particle size distribution and land use compatibility. With the explanation that in the analysis of the dimensions and physical infrastructure and support multi-criteria decision-making methods (model Todim) and produced for the processing of the above mentioned methods, is used Arc GIS software. This study is applied and in terms of methodology, quantitative comparative and analytical. This study from to goal ,applied and in terms of methodology, quantitative- comparative and analytical.

International :::union::: strategy for disaster risk reduction program titled "Strengthening the resilience of nations and communities to disasters" in the Hyogo Framework for 2005 to 2015 plan adopted, The program, in addition to reducing vulnerability of communities in crisis, will tend to increase and improve the resilience of communities.

Hyogo Framework for Action (HFA) to motivate more active at the global level in the wake of the International Decade for Disaster Reduction natural framework (2000-1990) and Yokohama Strategy adopted in 1994 and the International Strategy on Disaster Reduction (UNISDR) in 1999, was formed. After the Hyogo Framework period (2015-2005) in order to improve the resilience of nations and communities to disaster, Sendai framework (2030-2015) aimed at the Third World Conference of the United Nations Disaster Risk Reduction in Sendai, Japan in dated March 18, 2015 was adopted.

Generally, in this paper, according to the definitions and objectives resilience, resilience include: 1. The destruction and damage that a system can absorb, without being out of equilibrium, 2. The ability of a system to organize and self-renewal in different situations and 3. Create and increasing learning capacity and strengthen the system's ability to cope with the situation.

In this study, the analysis and evaluation; district and Evaluation criteria include the quality, type of structure, building, old building, the facade of the building, building density, particle size distribution and consistent user. With the explanation that in the analysis of the dimensions and physical infrastructure and support multi-criteria decision-making methods (Todim,s model) And for processing materials produced by the above mentioned methods, GIS software ARC GIS, is used. Todim,s technique is one of the techniques used to solve multi-criteria decision making problems. The technique using pairwise comparisons among decision criteria, accidental incompatibilities of this comparisons to remove it. In this study, according to seven criteria affecting the physical dimensions and infrastructure (quality building, building structures, old building, the facade of the building, building density, particle size distribution and consistent user) to assess the resilience of the 24 districts in Zanjan, a matrix of 24 * 7 production was.

After performing calculations according to the formulas described in steps 1 and 2 of this technique, the performance of each supplier to obtain. Finally, according to the formula Step 3 to obtain the minimum and maximum for each criterion to rank the areas according to the values 0 and 1 action. The highest value obtained from the best available option. This study is applied and in terms of methodology, quantitative comparative and analytical.

Our results can be inferred from That regions corresponding to the North and East of Zanjan due to Old low and relatively new texture That neighborhoods Zibashahr, Amirkabir and PayenKoh, Golestan Andishe and Daneshgah alley, Golshahr Kazemieh, poonak, Vahidieh and Ansarieh covered And most have regular access to the local system and network resilience were presented. But the central and southern parts of city, That old and historic neighborhoods such as Hosseinieh and Bazar, Yidde Borogh, Yery mosque and Dbaghlar are included ,Because of Ancient and worn out textur and also Islamabad Neighborhoods, trans and Bisim, Fatmieh as problematic texture, the degree of resilience of poor and very poor were evaluated. Given the discussion above earthquake fault lines that crosses the city from two sides, Strength and high-level security measures should also be implemented in the arteries of infrastructure and structural elements. On the other hand, in the historic old city neighborhoods in the city should strengthen endogenous development based on standard building regulations 2800 and the geographical structure of the region be made available.


Mohamad Salmani, Nasrin Kazemi Sani Ataallah, Badri S. Ali , Sharif Motavaf,
Volume 3, Issue 2 (5-2016)
Abstract

Human communities are affected by hazards, disasters and catastrophic events throughout history, including natural disasters (such as: earthquakes, hurricanes, floods, tornadoes) man-made disasters (such as: nuclear accidents, explosions, socio or political crisis, economic disturbances). Therefore, catastrophic events can have human or natural causes. These conditions show that human communities not only ever been stable, but they are continuously unstable and are exposed to disarranging events. Godschalk knows resiliency an important goal for two reasons. “First, because the vulnerability of technological and social systems cannot be predicted completely, resilience –the ability to accommodate change gracefully and without catastrophic failure- is critical in times of disaster. If we knew exactly when, where, and how disasters would occur in the future, we could engineer our systems to resist them. Since hazard planners must cope with uncertainty, it is necessary to design communities that can cope effectively with contingencies. Second, people and property should fare better in resilient communities struck by disasters than in less flexible and adaptive places faced with uncommon stress. In resilient communities, fewer building should collapse. Fewer power outages should occur. Fewer households and business should be put at risk. Fewer deaths and injuries should occur. Fewer communications and coordination breakdowns should take placeStructural analysis is first of all a tool of structuring the ideas. It gives the possibility to describe a system with the help of a matrix connecting all its components. By studying these relations, the method gives the possibility to reveal the variables essential to the evolution of the system. It is possible to use it alone (as a helps for reflection and/or decision making), or as part of a more complex forecasting activity. This method has 3 phases. Phase 1: considering the variables: The first stage consists in considering all the variables characterizing the studied system (external as well as internal variables); it is good at this point to be the most comprehensive possible and not to exclude, a priori, any possible path of research. Phase 2: description of the relations between the variables: In a systemic vision, a variable doesn’t exist other than as part of the relational web with the other variables. Also, structural analysis allows to connect the variables in a two-entries table (direct relations). Phase 3: identification of the key variables: This last phase consists in identifying the key variables; first, by a direct classification (easy to realize), then by an indirect classification. Direct classification:  The total of the connections in a row indicates the importance of the influence of a variable on the whole system (level of direct motricity). The total in a column indicates the degree of dependence of a variable (level of direct dependence). Indirect classification: One detects the hidden variables thanks to a program of matrix multiplication applied to an indirect classification. The structural analysis method seeks to highlight key variables, hidden or not, in order to ask the right questions and encourage participants to think about counter-intuitive aspects or behavior within the system. The direct influences of each variable on the set of other variables are illustrated in matrix form. Each element of the matrix represents an influence (0 = no direct relationship of influence on the two variables considered; 1 = a direct relationship of influence). We also took into account the level of influence between two variables. The following convention was used: 1 = low relationship; 2 = average; 3 = strong; P = potential relationship.. P levels were also given 0-3 ratings. By reading the matrix, we can classify the variables by their -level of direct influence: importance of influence of a variable on the whole system, obtained through the total of links created per line; - level of direct dependence: degree of dependence of a variable, obtained by the total of links created per column. The direct and indirect influences of the variable represent the system the most realistically. Highlighted are the determining factors (main determinants) of the situation under investigation. The input variables and result or output variables help participants understand the organization and structuring of the system under the microscopeBased on the results of direct influence matrix, social, economic and institutional variables are effectiveness in comparison to others. They have a great impact on system but physical variable effectiveness is much less than its impact. Among of mentioned variables, institutional variable had a significant numerical difference. Indirect cross-impact matrix showed significant differences in the institutional and social variables compared to other variables in the effectiveness and affected. The results indicate the high impact of these two variables on the system. In other words, institutional and social variables were influential factors in their community resilience. According to the results of direct influence matrix, strategic and key factors are including participation, assistance and interactions from social variables, readiness from intuitional variable and in indirect influence matrix; these factors are including participation, social identity, assistance and interactions from social variables and readiness from intuitional variable. Distribution of factors in axis influences of direct and indirect suggests that this system is unstable.


Jalal Karami , Aminah Mohamadi, Mohammad Sharifikia,
Volume 3, Issue 2 (5-2016)
Abstract

Resilience are concepts that are finding increasing currency in several fields of research as well as in various policy and practitioner communities engaged in global environmental change science, climate change, sustainability science, disaster risk-reduction and famine interventions (Vogel, et.al, 2007). Where the risk is a probability of damage, injury, liability, loss, or any other negative occurrence that is caused by external or internal vulnerabilities, and that may be avoided through preemptive action (Benson, et.al, 2004). Among natural disasters, earthquakes, due to the unpredictable nature of these events, are one of the most destructive. Iran is one of the most earthquake-prone countries in the world that its cities most affected by this phenomenon. Among the cities of Iran, Tehran, as the country's first metropolis, due to dense population, poor physical development, structural density, and lack of standards, is potentially facing a serious threat. The purpose of this study is to investigate the spatial flexibility of Tehran over the region 12 after the earthquake incidence.

The present study is dealt with the data preparing and analysis using geospatial methods. The several geospatial data such as Peak Ground Acceleration (AGA) map, urban structure, infrastructure and population collected from Tehran Disaster Management Center were provided and analysis based some GIS known algorithms. In other to urban spatial resilience zonation the AHP (analytical Hierarchy Process) was implemented to generation risk map. Finally OWA (Ordered Weighted Average) method was implemented in order to Production spatial flexibility map of earthquake incidence over the District 12 of Tehran. AHP model uses of priorities straight experts, but OWA provides of control the level of compensation and risk-taking in a decision. Using the conceptual of fuzzy quantifier with OWA makes the qualitative data analysis enter to decision.

    According to flexibility of the final map with fuzzy operator (All) equivalent to the operator MIN, the worst result Was obtained and resulting the highest risk and lowest flexibility respectively (Districts Nos. 2,12,7,8 and 11).By taking all the criteria of a criterion without compensation by other criteria as "non-risk" is obtained .

Map obtained with fuzzy operator (Half) has the high potential to provide suitable options,  because in addition to integration criteria the importance of each parameter based on the weight given to the criteria are considered. In this map Districts Nos.2.6 and 8 (Baharestan, Emamzadeyahya and Sanglajedarkhangah) respectively were most Risk to earthquakes and therefore less flexibility to the earthquake. The map obtained with the fuzzy operator "Atleast one" is equivalent to MAX operator districts Nos. 2,12,7 and 8 (Baharestan ,DarvazehGhar of Shush,Abshardardar and Sanglajedarkhangah)  respectively were most Risk to earthquakes and therefore less flexibility to the earthquake.

The fuzzy conceptual map quantifier showed that districts Nos. 2 and 12 (Baharestan and DarvazehGhar of Shush) were most vulnerable and therefore less flexibility to the earthquake as final results.


Saeed Balyani , Mohammad Saligheh,
Volume 3, Issue 2 (5-2016)
Abstract

The results of this study indicated that the synoptic patterns that lead to heavy rainfall in 22 March 1996, 24 mar 1995 and 17 November 1994 in the northern portion of FARS province includes: the low pressure that located in eastern part of Mediterranean and Black sea and southern part of Caspian Sea that created by trough that located at the middle level of atmosphere. In addition to this low pressure, the bipolar pattern in of Saudi Arabia  having negative vorticity that lead to transporting moisture from (India ocean, Red sea, Arab sea, Persian gulf and Oman Sea )   and also to be alignment with east Mediterranean sea and black sea low pressure as ascending agent lead to precipitate of rainfall in mentioned days . and also we found that in 29feb 1996 as second patterns rainy day, a strong deep trough transporting moisture from Soudan region and east Mediterranean  low pressure, cause alignment of this atmospheric systems. In fifth patterns (21 mar 2001), existing an low pressure and positive vorticity center in east of Pakistan simultaneously with existing negative vorticity center in central part of Iran, lead to high pressure gradient which cause rainfall events in study area. The main founding of this study were that reveals the role of low pressure of east, north and south of Caspean sea in heavy rainfall events in study area.

Pre-warning of natural hazards events such as heavy rainfall has a significant effect in damage reducing. The analysis of synoptic-dynamic condition of atmospheric circulation patterns, has great importance in recognize affective agents in heavy rainfall events. Especially this heavy rainfall could lead to flash floods suddenly. This study's aim is to analysis and extraction of daily heavy Rainfall lead atmospheric patterns in northern portion of Persian gulf (Helle and Mond Subbasin).

The study area, Helle and Mond basins, with about 21,274, 47653 km2 area,respectively are located in the south of Iran. The Helle basin approximately is between 28° 20'N and 30° 10'N latitudes and between 50° E and 52° 20'E longitudes and Mond basin is between 27° 20' and 29° 55' latitudes and between 51° 15' and 30° 27'E longitudes.These basins are located in sides of a massive sources of moisture, Persian Gulf.

In this study we investigate the data of daily rainfall of 37 synoptic and meteorological station of study area during 1991 to 2011(20 years) to extraction the atmospheric patterns lead top heavy rainfall. In this study in order to archiving heavy rainfall days based on 95 percentile in study area, the data of sea level pressure, geopotantial high of 300 and 500 hp and also data of verticit and stream line and omega in the spatial framework of -10 to 100 longitude and 10 to 70 Latitude has been selected. Then we create the sea level pressure matrix as rainfall associated days, based on Lond method of Correlation to classify days.

Our founding indicated that the main synoptic systems that lead to heavy rainfall is related to low pressure in eastern Mediterranean  and southern part of Caspian sea. So that in detected rainfalls patterns shown that the transporting moisture from nearby sea by high pressure of Saudi Arabia by associating eastern Mediterranean low pressure and deep strong trough in east and southern part of Caspian sea  cause heavy rainfall events in study area. So that the low pressure located in eastern and southern portion of Caspian sea could affect the study area.


Alireza Mohammadi, Bahman Javid Moghvan,
Volume 3, Issue 3 (10-2016)
Abstract

Most of the large cities in developing countries have faced with the problem of informal settlements. The formation and growth of these settlements for reasons such as rapid and outside the customs building construction are the threatening issue for their communities. Informal settlements are areas that often shaped and expanded in major and middle cities of the Iran’s cities including the city of Parsabad. During the last decades, the rapid growth of urbanization and the lack of appropriate planning for low-income families housing leads to the formation of the urban informal settlements in most cities of the Iran. In most cases, these settlements have a structural and demographic dense texture. The structural texture of these settlements is often fine aggregate, impermeable, and unstable. In times of crisis, the possibilities of human and material losses to them are high.

Environmental hazards such as earthquakes are a serious threat to these settlements. However, these hazards in most developing countries, due to the unavailability and lack of preventive actions, end to the crisis. We cannot prevent earthquakes. But we can reduce the losses and damages caused by the earthquakes. Remove of the disaster is impossible, but it is possible to reduce the damage caused by the disaster. One of the most important ways to reduce the risk of earthquakes is preparation to deal with earthquakes. Preparation means having previous programs and plans.

     Iran is one of the countries where earthquakes always happen. Because Iran located in the world's earthquake belt, each year on average about 1,000 earthquakes happening in Iran. Ardebil and Pars-Abad city, located in an area that the possibility of earthquakes shakings in these areas, is more. The Zire Nahre Torab Neighborhood is one of the Parsabad city’s informal settlements that located in the northwest of the city. Regarding the possibility of an earthquake in the city of Pars Abad, identification and assessment the vulnerability of the neighborhood during an earthquake, is essential. Therefore, identifying and assessing the vulnerability, especially in the poor neighborhoods to offer strategies for dealing with the injuries, is essential. The aim of this study is assessing vulnerability of the informal settlements during an earthquake by using spatial data and GIS. This study, have been prepared in fifth main parts including: introduction and background, methodology and presentation of case study, theoretical framework, analysis and conclusions.  

This research in terms of the nature is practical and is descriptive and in terms of the method is analytical. Three methods including library, documentary and survey have been used for data collection. In the first phase, data and base maps were extracted from documents and reports of projects such as city comprehensive and detailed plans. Also, in this phase of the study data were updated. In the second phase, the problem, questions and research objectives were defined. In the third phase, the 3 criteria and 12 sub-criteria based on research literature and according to available data were selected. In the fourth phase, after preparation of databases related to each of the criteria in GIS, input layers were prepared for each of them. In the fifth step, the method of network analysis process (ANP) was used to determine the significance of criteria. In the sixth phase, the weighted overlay index (WOI) was used for combining output layers.

The results of this study show that more than 80% of neighborhood buildings are vulnerable against the risk of a possible earthquake. Also, research findings suggest that physical characteristics such as building structure, quality and age of the buildings will have the greatest role in determining the neighborhood buildings vulnerability level. Doing activities such as resisting buildings, improving roads, locating facilities in appropriate places, training and informing citizens to prevent a crisis caused by the possible earthquakes, is essential. Other recommendations are listed in below:

  1. Identifying vulnerable buildings
  2. The use of GIS in the management of settlements
  3. Preparations cities, to deal with urban hazards
  4. Empowering citizens to deal with environmental hazards
  5. Action to reduce earthquake risk
  6. Civil engineering Renovation of buildings
  7. New practices in the urban construction
  8. Equip cities with facilities and relief supplies.
  9. The use of specialists in urban planning.
  10. Conducting workshops on urban resilience.


Khalil Rezaei,
Volume 3, Issue 3 (10-2016)
Abstract

Erosion is one of the most destructive and continuous phenomena that cannot be prevented and only could be controlled by studying the chemical and physical properties of soil. Marls are one of the most important sedimentary units in Iran which have high rate in sediment production and erodibility because of their Physico-chemical characteristics. These properties caused large environmental and civil damages and so, the study of erosion and erodibility of the marl units is essential. One of the most important points about marls is grain size nature and elements in them and their effects on amount of erosion. The physical and chemical proprieties of soil are very important in the development of badlands. This study deals with Physico-chemical properties of Marl and its impact on various land forms of erosion in Lotshur-Pakdasht region. Badlands are a typical landform of greatly dissected fine-grained materials in arid or semi-arid environments like Lotshour, although they are also found in different climatic conditions. Climate and geology are several factors determining the tendency to badland formation. Runoff, rain splash, marl and loose formations together with massive wasting processes such as creep, sliding and flow, become the dominant factors determining landform genesis, resulting in the formation of badlands in Clayey-silt slopes.

In this research, in addition to sampling the soil and sediments, rain simulated (using rain simulators) in two marl, two conglomerates and two alluvium  units, in area with different forms of erosion and runoff and produced sediment amounts in each point were measured in laboratory. Also, at the same time, soil samples were taken from adjacent plot and the amount of runoff and sediment produced in the laboratory, separated and measured in the lab for all points. parameters such as Ph, electrical conductivity, content of sodium, potassium, calcium, magnesium, gypsum, chlore, carbonate, solfate, nitrate, organic carbon, CEC was measured. In analyzing the data, analysis of correlations and Pearson and Spearman comparison of means method were used in SPSS software. Also, grain size and Aterberg limits for all samples were determined in lab.

Mineralogical, geochemical and grain-size composition of soil and pore-water chemistry parameters was characterized on both eroded (south-facing) and non-eroded (north-facing). Only a few grain-size parameters and mineralogy discriminate eroded from non-eroded slope substrates. Erosion occurs where the fine fraction is abundant. This may be due to reduced permeability in the eroded soil, whereas the non-eroded one is more stable with respect to weathering, as it is more permeable. The abundance of clay minerals is affected by pedogenetic processes in the non-eroded slope, which increases in mixed layers and indirectly reduces the amounts of other minerals, making clay mineralogy a discriminating parameter in the two different types. Chemical data enable discrimination between eroded and non-eroded slopes. pH, SAR (sodium adsorption ratio), TDS (total dissolved salts), mineralogy and PS (percentage of sodium) are distinctive parameters for both eroded and non-eroded slopes. TDS increases in depth in the non-eroded slope, whereas the maximum TDS is just below the crust in the eroded one. On average, eroded substrates are higher in pH, SAR and PS than non-eroded ones. The ESP (exchangeable sodium percentage) of the eroded slope has a higher value than the non-eroded one. Crusts are less dispersive than eroded substrates, and non-eroded substrates behave as crusts. This suggests that the portion of the slope most severely exposed to weathering tends to stabilize, due to strong decreases in SAR, PS and ESP. Several diagrams reported in the literature show similarly anomalous crust samples on eroded slopes, compared with other samples coming from greater depths on eroded slopes. In the present case study, the exchangeable form of Na characterizes crusts more than the soluble form. The meaning of maximum SAR and TDS (and covariant parameters) is interpreted as the effect of decreased permeability, as suggested by a local increase in the fine-grained fraction, which coincides with maximum TDS. Variations in SAR values are of primary importance for soil erosion, because many authors have used solution chemistry (i.e., SAR, PS, TDS, EC) as a descriptor of dispersity.

            Based on results of analysis of variance in various forms of erosion are significantly different in the sodium ion, sodium absorption ratio and the percentage of clay. The average amount of sodium ion and sodium absorption ratio in marl samples of region, increase from sheet to gully erosion forms while average clay percentage decreases in this trend. Finally, three variables of sodium ions, sodium absorption ratio and clay percentage of marl samples can be significant factors in erosion and related forms in this region. This study describes the erosional mechanism, which involves morphological and geographic exposure and climatic elements, as well as grain size, mineralogy, chemistry and exchangeable processes of soils.

In analyzing the data, correlation analysis and comparison of averages by the SPSS software has been used. As well as a brief comparison between north and south facing slopes that are different in terms of erosion, was also performed. Based on statistical analysis of in various land forms of erosion are significantly different in the sodium ion, sodium absorption ratio and the percentage of silt and clay. The average of sodium ion value and sodium absorption ratio increase from surface to gully erosion form and average silt percent reduced from surface to Gully erosion in marls outcrops in this area. Also, three variables of sodium ions, sodium absorption ratio and clay percent factors can be seen in the erosion of marl and create various land forms of erosion in the region.


Meisam Moharrami, Ali Akbar Rasuly, Hashem Rostamzadeh,
Volume 3, Issue 3 (10-2016)
Abstract

Urmia Lake is one of the largest hyper saline lakes in the world and largest inland lake in Iran which located in the north west of Iran, between the provinces of East Azerbaijan and West Azerbaijan. The lake basin is one of the most influential and valuable aquatic ecosystems in the country and registered as UNESCO Biosphere Reserve. In addition, it is very important in terms of water resources, environmental and economic. Unfortunately, lake water level has dramatically decreased in recent years, due to various reasons. This issue has created some problems for Local people, especially people living in rural area in east of the Lake. The results of this research are of great importance for regional authorities and decision-makers in strategic planning for people of inhabits in east coast village.

The present paper is an attempt to integrate a semi-automated Object-Based Image Analysis (OBIA) classification framework and a CA-Markov model to show impacts of Urmia Lake Retrogression On eastern coastal villages. OBIA present novel methods for image processing by means of integration remote sensing and GIS. Process and outcome of this methodology can be divided in three step including: Segmentation, Classification and Accuracy assessment.in the process of segmentation aims to create of homogeneous objects by considering shape, texture and spectral information. A necessary prerequisite for object oriented image processing is successful image segmentation. In our research the segmentation step was performed by applying multi-resolution segmentation and considering 0.2 for shape and 0.4 for the compactness. The scale of segmentation is also an important option which leads to determine the relative size of each object. Having great values for scale leads to create large objects while smaller value would result small objects respectively. In this study the scale parameter of 100 has been selected based on the size of objects in Scale of study area as well as spatial resolution of the satellite images were used for segmentation. In doing so, we employed spectral and visual parameters contains: texture, shape, color tone and etc. for developing object based rule-sets.  To determine the characteristics of the spectral data and geometric features classes the fuzzy based classification was performed by employing fuzzy operators including: or (max) operator with the maximum value of the return of the fuzzy, the arithmetic mean value of fuzzy and the geometric mean value of fuzzy, and (min). After this step, the validation process was performed by using overall accuracy and Kappa coefficient. Then, using the CA-Markov Model The trend of changes was predicted in the future (For 2020). Another way to predict changes in land use and cover, used the CA-Markov model. Markov chain analysis is a useful tool for modeling land use changes. Markov chain model consists of three step: First step Calculating the probability conversion using Markov chain analysis, second step, Calculating the Cover and land use maps competently on the basis of multi-criteria evaluation, third step, assign locations cover and land use simulation based on the CA position operator.

Results of Satellite image processing indicate that the area of garden, Farmland, Zones of muddy-salty (Saline soils), moist salt and newly formed salt have increased while area of Urmia lake has rapidly dropped between 1984 and 2015. The area of Urmia lake declined from 4904.51 square kilometers in 1984 to 676.79 square kilometers in 2015. The farmland area increased from 177.72 square kilometers in 1984 to 542.37 square kilometers in 2015. The garden area increased from 83.71 square kilometers in 1984 to 227.28 square kilometers in 2015. The moist salt area increased from 111.89 square kilometers in 1984 to 945 square kilometers in 2015. Zones of muddy-salty (Saline soils) area increased from 859.01 square kilometers in 1984 to 2986.5 square kilometers in 2015. The newly formed salt increased from 171.27 square kilometers in 1984 to 921.99 square kilometers in 2015. Markov chain model results indicate in 2020 the garden area will be 638 square kilometers, the moist salt area will be 717 square kilometers, Zones of muddy-salty (Saline soils) area will be 4127 square kilometers, the farmland area will be 644 square kilometers, the newly formed salt area will be 363 square kilometers and the Urmia lake area will be 118 square kilometers.


Said Balyani, Yones Khosravi, Alireza Abbasi Semnani,
Volume 3, Issue 4 (1-2017)
Abstract

Hazard is potential source of harm or a situation to create a damage. So identification of zones exposed to hazards is necessary for planning or land use planning. But this situation becomes more critical when they appear at the population centers. So applying the principle of passive defense based on environmental capabilities is unarmed action that caused the reduction of human resources vulnerability, buildings, equipment, documents and arteries of the country against the crisis by natural factors such as drought, flood, earthquake, etc. Considering the possible occurrence of such risks in population centers, ready to deal with what is known unpleasant and undesirable consequences is necessary. On this basis and given the importance of population centers in Helle and Mond basins, in this study, the authors tried to analyze the Rain hazards of drought and flood.

The study area,Helle and Mond basins, with about 21,274, 47653 km2 area, respectively are located in the south of Iran. The Helle basin approximately is between 28° 20'N and 30° 10'N latitudes and between 50° E and 52° 20'E longitudes and Mond basin is between 27° 20' and 29° 55' latitudes and between 51° 15' and 30° 27'E longitudes.These basins are located in sides of a massive sources of moisture, Persian Gulf.

In this study, data from 23meteorological and synoptic stationsstations, during aperiod of20 years (1992-2011)in northern region of the Persian Gulf (Mond and helle basins)were used to calculate Standardized Precipitation Index (SPI). The data were collected by the Iranian Meteorological data website (http://www.weather.ir). The SPI is primarily a tool for defining and monitoring drought events. This index may be computed with different time steps (e.g. 1 month, 3months, 24 months). The SPI is defined for each of the above time scales as the difference between monthly precipitation (xi) and the mean value ( ), divided by the standard deviation. To assess flood risk zones, the flood, annual evapotranspiration, cities and populations centers layers were collected in Helle and Mond basins position. The annual precipitations and the SPI maps were drawn by Geostatistics, Kriging. It also the flood and annual evapotranspiration layers were weighted by Euclidian distance method, separately. Finally, all layers are weighted by AHP and fuzzy-linear methods (descending and ascending linear function) into vulnerable layers. The final map of vulnerable areas with flood and drought high risk was drawn based on the algorithm of linear-Fuzzy in a raster format.

According to the results, eastern, north eastern and south eastern part of Mond basin had high annual precipitation. Based on this result, it said that these parts of study area were known the least dangerous areas of vulnerability. The results also showed that with passing of the western regions and going to the center of the study area the annual rainfall have been added over the years. Kazeron, Chenar Shahijan, Firouz Abad, Borm plains and some parts of Khane Zenyan and Dash Arzhan are cities located in this regions. Low latitude, Proximity to the warm waters of the Persian Gulf, low annual precipitation and high temperature causing evaporation and inappropriate environmental conditions in Boushehr province and some coastal cities such as Genaveh, Deilam, Boushehr, Baghan, Lar and Khonj. Accordingly, west, north west, south and south west regions in Helle basin were located in extreme vulnerability zone with a loss of annual rainfall for drinking and agricultural production and poor nutrition underground aquifers.



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