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Showing 344 results for Type of Study: Research

Manijeh Ghahroudi Tali, Khabat Derafshi,
Volume 2, Issue 2 (7-2015)
Abstract

Flood as a natural disaster follows certain erratic patterns which was made confounding factor. Flood risk is variable and complex that depends on very phenomena such as rainfall, runoff concentration and high exposure of the flooding downstream areas.

    This are changes over time and from regions due to natural conditions, human activities, and damage culture of the community at risk. Occurrence of chaos at flood risk changes the trend of predictable processes. In the other words, although flood is a disaster, the occurred irregularities in its patterns can reveal its complicated nature. Flood pattern irregularities are the incident evidence of chaos in the system which can be studied by fractal geometry. The occurred events in spatial variability of floods in the last 50 years show they can be occur as unusual urban flood in Tehran.

    Tehran city may experiences the difference life and property damages because the high varieties in the socio-economic and the life quality level in regions, also structural varieties in the city fabric??. Ignoring the natural factors in spatial planning, overrun and destruction of natural morphology as a result of urban activities and subsequently disturbing urban drainage system lead to unpredictable and destructive floods in Tehran.

    The Tehran precipitation layer was prepared based on 27 weather stations data in the period of 10 years (1998-2009) and Kriging model with a Gaussian function. The runoff is calculated by Soil Conservation Service Curve Number (SCS-CN) and precipitation layer. The flood hazard potential map has been created by 8 variables and Analytic Hierarchy Process (AHP). This map as an index to define the said complexity was prepared in 5 categories of risk by combination of Tehran metropolis flood hazard and vulnerability maps. Then it was divided into hydrological basins and 12 basins were selected randomly. The Perimeter-Area Fractal and Number-Area Model were used to study the chaos and turbulence in the Tehran’s flood pattern.

     Explanation of locational changes of risk between the basins needs to calculate the weighted average risk and the independent variables in 12 basins that obtained by zonal statistics. Based on these average values the factor analysis used to determine the Varifactors or main components of the variability in flood risk between the basins. Finally, fractal geometry models (perimeter-area and cumulative number-area) were used to demonstrate the chaos of the flood risk value in 5 categories of risk.

    In this research the Tehran flood zoning map was calculated at 5 hazard categories. The fractal of sample basins had increased by increasing in the level of hazard map. Generally, the higher DAP values from 1 represented increasing in the chaos or irregularities of Tehran floodhazard. The obtained DAP from very low to very high risk levels are 1.206, 1.216, 1.23, 1.263 and 1.293 respectively. The increasing of DA indicated that turbulence hazard increases based on Perimeter-Area fractal model, thus, with the increase in hazard the DAP and DP values were greater. Also, the results of Number-Area Model showed turbulence floods in the five classes of hazard. The area cumulative number of risk levels are 0.74, 0.79, 0.85, 0.86 and 0.88 respectively; this trend showed the less size of flood risk polygons from very low to very high risk levels. In the other words, by increasing the risk level the polygons gets smaller and indicates the increase the flood risk chaos.

    The occurrence pattern of natural phenomena and even natural hazards have a regularity type in normally condition; if this regularity disrupts for any reason, irregularities or chaos happens. In present study, the results of fractal analysis in sample basins presented the chaos pattern in Tehran floods. Also the heavy rainfall can be predicted in Tehran but the prediction of the flooding distribution was not provided. According to the recorded floods in Tehran the flooding begins always in the northern valleys of Tehran, like Darband, Kan or Golabdareh basins,  are not similar to damage pattern. As a result, despite several studies and projects which have been implemented about flood phenomenon in Tehran, this is unpredictable and uncontrollable in the city.


Mahmoud Ahmadi, Hassan Lashkari, Parasto Azimi,
Volume 2, Issue 2 (7-2015)
Abstract

Understanding the climate of a region as a first step and most immediate action is considered research for development projects Climatic phenomena such as floods every year irreparable damage to the soil, pastures, forests, urban and rural facilities, human and animal import Climatic phenomena such as floods every year irreparable damage to the soil, pastures, forests, urban and rural facilities, human and animal import. The first factor in causing flood is rainfall intensity that occurs at a certain time. Therefore necessary infrastructure projects, and one of the main issues in hydrological and hydro-climate is awareness of the occurrence and amount of rainfall, most likely for different periods.

     In order to implement the model of Synoptic convergent in this research and estimated probable maximum precipitation in the South West region of the Caspian

   1: The 1:50,000-scale Digital Mapping the location of all stations in the study area, Climatology, rainfall and hydrometric surveys in selected were identified on the map.

   2: The maximum instantaneous discharge rate of the highest daily rainfall stations selected surveys (1976-2011) are also studied.

   3: collection of the highest daily rainfall statistics selected stations, monthly and annual precipitation data for the period (1986-200),Facts about the daily atmospheric phenomena (cloud, wind speed, dew point temperature, air pressure) with an interval of 3 hours to 3 hours, Statistics continuing 12-hour maximum dew point of the surface (in degrees Celsius) and wind speed times (NAT) for the stations of Anzali, Rasht, Astara, Ramsar, Ardabil, Pars Abad For the first 10-day period, 10-day and 10-day return period for calculating the 50-year-old third, 80-year and 100-year and monthly statistics on the average pressure of the selected stations establishment station.

   4: Select the desired storm rainfall in 24 hours and 48 hours to obtain a return period of 50 years, 80-year and 100-year 12-hour maximum dew point and wind speed persistence for long periods, the separation of each month, and the resolution of each decade, through software SMADA and HYFA.

   5: Purvay of Rain maps and DAD chart is also the main stages of this work.

   6: Finally, weather maps, humidity maps and omega air maps at ground level, 700 level and 850 hp prepared from

    Days prior to completion until the day of rain showers in the stormy period from the NCEP / NCAR site and was ready in GRADS software environment.

     In order to realize the adiabatic saturation warmest period of the most intense storms in 1355-1390The maximum instantaneous rate of discharge and daily rainfall statistics, the most comprehensive and stations on their occurrence in the previous chapter, was studied.So the four pervasive  hurricane was  selected. Then, rain storms map were plotted in the GIS software environment and use of IDW method and Using data from the windy days selected on rainfall stations in the study area. In order to obtain the rainfall in the whole region,were regressed  between the two parameters: precipitation and elevation; and was estimated average of rainfall in the cumulative area and rainfall amount in during of the storm days. Based on the height - area tables of ​​each storm separately, DAD curves was drawn based on average rainfall in columns cumulative and cumulative area. Then we reviewed and interpreted weather maps at ground level, elevation Maps, humidity maps and omega maps at 850 hPa level. Survey maps showed Tongue of immigrant anticyclons in North West Europe that usually is deployed on the Black Sea will advection cold air from the above widths on the Caspian sea and is transmited very wet weather to the south and West south Caspian Sea. After analyzing weather maps, the next step is obtain  to water for showers.To calculate the rain water the best way is getting the hottest adiabatic saturation that occurs with the maximize the dew point temperature and wind speed. After obtaining the maximum dew point and wind speed factor, we would like to calculate the coeffcient storm. After obtaining the coefficients of the storm,obtained its P.M.P by multiplying the amount of rainfall for each storm.

     According to the obtained PMP,was adopted rainfall continued for 24 hours with the numbers 276/95. PMP obtained showed that the storm dated 2/10/2001 of 24-hour duration, has been most intense and pervasive from the two other samples.


Javad Sadidi, Hamed Ahmadi,
Volume 2, Issue 3 (10-2015)
Abstract

The term "Game GIS” implies to real spatially enabled games in which a special part of the world is virtually simulated, represented and managed. In fact, game GIS is an integrated system consists of video games and geographical information systems, aimed to simulate and representing spatially enabled environment. The achieved result of implementing a game GIS service can be exploited before a crisis for wise designing of a city and diminution of the aftermath casualties. As the decision making process plays the key role to reduce the losses, the need arises for using the models as much as close to the reality. By this, it is possible to use the virtual world in in the form of a game rather than experiencing the real world with real wounded and killed persons in. This enables us to recognize and manage a test environment for promoting the managing the real environment of a city during and before a natural hazard disaster like an earthquake. The game GIS may be counted as a service for sharing and dissemination of spatial information as well as online GIS to have a visual and synoptic management of the earth plant facing various disasters. The current research is aimed to design and implement a software architecture for an earthquake game in Tabriz city (Iran).

The study area is district 10 of Tabriz located within a fault zone. According to field surveys, 82.1 percent of buildings in the study area may be vulnerable against earthquake in terms of the quality of building construction.

Methodology of the research to design, program and implement the game GIS service are undertaken as the following processes: data collection, database creation and software production.

The collected data includes master plan maps of the district 10, building quality, number of floors, building façade materials, age of building, street network (adopted from the master plan of Tabriz) and population of each parcel.  Also, some regions are assumed as hospital, relief-rescue center and treasury money.

To design the software, 2D environment of MapControl and for implementing the game into the 2D environment, ArcEngine of ArcGIS have been exploited. The mentioned engine gives us possibility to use of analysis and modelling capabilities as much as closer to the ground reality which are compatible with available geometry of the terrain (Amirian, 2013, 17-19). The MapControl is a framework in which the map and game area are displayed. Symbology is used to show the persons as well as equipments. Briefly, the stages undertaken during the current research can be explained as the following:

  • Data collection based on available sources via field surveying.
  • Data processing and creating a database from street networks and building owned the age, materials, floors fields.
  • Calculation of vulnerability rate for each building separately as well as the amount of deconstruction damage per Richter.
  • Drawing the street and alley network to prepare network analysis dataset.
  • Preparing special network analysis database and evaluation in various situations.
  • Using the gained layers and implementation of the scenario.

After that, the conceptual architecture of the software has been designed based on the scenario.

The game GIS services has been designed with 6 different classes offer numerous functionalities responsible for displaying program commands and different views of the game. Finally, the service is designed and implemented in a real schema for crisis management application. The resulted game is played in 4 stages. In the first stage, the player starts with a 5 Richter magnitude earthquake and ends while the player gets to 8 Richter. The designed software simulates the destruction rate of buildings based on the influential factors, wounded transfer routing and rescue operation. The game player gains credit according to his quickness and agility. The player would go to the next stage with one Richter magnitude higher, if gains enough credits during each stage. The result of the current research as a Game GIS service, can be used in earthquake simulation happens in various magnitudes for management of decreasing the effects of earthquake, quick reaction, maneuver and education. Considering the achieved results, designing and performing the game GIS service over the web based on open source technologies rather than being desktop and commercial service, can be suggested as a new research frontier for the future researchers.


Bohloul Alijani,
Volume 2, Issue 3 (10-2015)
Abstract

Spatial analysis as the main approach of geography was reviewed and searched through its historical development. The results of this exploratory research showed that this approach was born after the Second World War due to the overall interest of geographers to develop universal theories and laws. The advocators of this field believed that the old regional geography was not able to develop a scientific and applied knowledge. The main motivation of the development of the spatial analysis was the quantitative revolution of the 1960’s which was triggered by the article published by Shaeffer in 1953. This was followed by some prominent geographers such as Bungeh, Ulman, Barry, Hagget, Chorley and others. Bungeh and Harvey strengthened the philosophical foundation of spatial analysis and others such as Hagget , Chorley and Hajestrand published important books in the field of quantitative geography. The main objective of spatial analysis is to analyze the distributions through the identification of their global and local structures and reasoning these structures by their spatial relationship with other distributions. In this regard it uses quantitative data and mathematical language to achieve the spatial theories and laws.

     The spatial analysis studies the spatial distributions and structures. These are the entities that are not subject to the human interpretation and thinking. This approach is true in the both physical and human geography. The knowledge it tries to achieve is the theories and laws about the spatial distributions. The methodology of spatial analysis is the quantitative methods such as experiment and survey. Thus in terms of ontology the entities of spatial analysis are independent of human mind and objective. The spatial characteristics of distributions are not constructed but discovered. The methodology used in spatial analysis is quantitative and objective including some methods such as experiment and survey. In 1980 and onward, human geography tried to move toward qualitative methods such hermeneutics but during 21st century all branches of geography are using quantitative methods more frequently than qualitative ones; but the use of the combined version of quantitative and qualitative methods is becoming more frequent day by day.

  The introduction of Geographic Information System as the operational environment for spatial analysis works the approach has become more widespread and dominant. Geographers are now able to analyze more spatial data and discover more spatial theories to solve the spatial problems. GIS is the main tool for spatial analysis and by introducing the science of geostatistics has improved the scientific and applied power of spatial analysis. The application of quantitative geography including geostatistics and GIS requires improved knowledge of mathematics, geometry and statistics; the main language of today geography. The spatial analysis covers the important topics of geography including spatial distributions, regions, spatial relations especially the relation between human and environment, spatial structures, spatial reasoning, interpolation, and the most important topic of spatial planning. The spatial analysis is the only scientific field to define and develop spatial planning. With correct and logic spatial planning there won’t be any environmental hazards. Because in any region all human settlements and activities are planned according the potentials of the region.


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.


Mohamad Saligheh,
Volume 2, Issue 3 (10-2015)
Abstract

Tehran, in the south of Alborz Mountains, is faced with three types of weather risk, weather risk caused by geography, climatic risks caused by air resistance and weather risk due to global warming. The aim of this study is to examine the three types of risk in Tehran. The method of this study was to evaluate the changes of synoptic factors that affect global warming and urban development. In order to detect the height changes of 500 hPa two 5-year periods including 1948 to 1952 and 2010 to 2014, were studied.

     The results showed that changes in heights of 500 geopotential, there was an increased risk in the city of Tehran. The effect of climate change in recent decades,  increased the stability of  air in Tehran. Human factors in the formation of heat islands, increase LCL height and density of the air balance is transferred to a higher altitude. Changing urban wind field, atmospheric turbulence intensified, exacerbated thermodynamic gradient, fat and refugee cyclones, heat island effect of the city.

Thermal stability in the warm period will appear. The thermal stability of all levels of lower, middle and upper troposphere was intensified. Thermal stability couraged the  development of subtropical high pressure in the area. With the arrival of the atmospheric pressure during calm and humid days the stability and pollution were increased. Negative vorticity from early June  developed the intensive high pressure over the region. Compare the conditions of the two study periods  showed that  : the height of the high pressure was 100 meters higher than the second period. The number of days of intensified subtropical high increased during the second period.  The high pressure has moved to the northern areas during the second period. This change in the subtropical high pressure increased the dry periods motivating the loss of vegetation. Heat island effect was increased as well. More than 90% of the  temperature inversions occurred  at an altitude of less than 500 meters in both warm and cold periods of year. Wind direction at both stations has shown that the establishment of any pollutant source in the West of Tehran will increase the pollution.


Manuchehr Farajzadeh, Yousef Ghavidel Rahimi, Sahel Mokri,
Volume 2, Issue 3 (10-2015)
Abstract

Forest fire is one of the important problems in Iran which is caused by different factors such as human and natural factors. One of these factors is climate conditions that can be created by heat wave and special circulation of atmospheric phenomena. Occurrence of forest fire in north of Iran have different impacts on environment such as destruction of natural. According to the position of Iran in the dry climate zone provides required conditions for this hazard. Unfortunately,every year thousands of hectares of precious green cover is burned. Forest fires have harmful effects on human life directly,or in directly and lead to environmental destruction and pollution, global warming, loss of vegetation, and dry soil erosion. As a result, research on forest fires will become necessary. The study region is Mazandaran province forests located  in north of Iran with area of  23756.4 square Kilometers.The main object of this study is to detect the forest fires using satellite data and associated analysis with synoptic approach based on weather maps.

To detect fire in the study area different satellite data such as  synchronized and geostationary satellite data were used. In this study, MODIS satellite imagery and global algorithm detection of fire to detect fire in the forest and meadows of Mazandaran province were used. The climate data including weather station data and weather map were used. Other data include data of LST and vegetation products of MODIS. In order to downscale the global data an appropriate threshold was defined. In the proposed method,  After geometric correction and radiometric the cloud mask was removed, And then fire potential was identified with different thresholds and tests. Three fire episodes of  Savadkooh 2006, Noor , 2009 , and Behshahr, 2010 were selected for study.

Results showed  a threshold value of 310 ° K for MODIS sensor band 22 is good for a global scale. Cold and small fires are not detected, Therefore Local threshold was used. In addition, surface temperature and vegetation mapping , chlorophyll amount of vegetation were used before and after the fire episode.It became apparent that the amount of chlorophyll was reduced and the temperature was increased after the fire.

   The synoptic maps of the fire day showed a low pressure over the region and mid level systems indicated the advection of warm air over the area. Surface stations showed the increase of temperature and reduction of moisture during the fire days over the long period mean values.

According to the results of the study the ground level data accompanied the upper level images and pressure patterns.

Universal high performance of fire detection algorithm was used  to identify areas of forest fires Using MODIS satellite images and global algorithm modified to suit the characteristics of the study area fire detection. Then three of the fires were identified with this method. The algorithms with MODIS images and weather data together indicated the validity of the study and performance of this algorithm to identify the location of fire in the study region. Therefore the method of this study can be used in other areas to detect forest fires.


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.


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.


Farhad Azizpour, Mohammed Saeed Hamidi, Jamshid Chabok,
Volume 2, Issue 4 (1-2016)
Abstract

Among the various environmental hazards, flood is the greatest and most important climate crisis which takes every year the lives of thousands people and impose severe damages on human society and environment. Today, it is clear that controlling all hazards, including floods is not possible. Suitable management can only minimize the damages. The literature on natural disasters management indicated that in the process of natural disaster management and their vulnerability mitigation, there are two dominant paradigm: technic-based approach and community-based approach.

Community-based approach welcome the local cooperation and participation in disaster management process and calls for strengthening local capacity through the participation of all individuals and groups at the local level. This approach is not only appropriate to provide solutions for disaster reduction, but build disaster preparedness. Because disaster preparedness planning requires special attention to local participation. In the geographic area of Bashar River Basin, due to the lack of suitable agricultural land and greater quantity of water for rice crop, villages have been built at rivers edge. So that, most of the houses and farms in the villages are located very close to the river. However, these locations are extremely vulnerable to flooding. This study reviews the status of local participation and its impact on reducing flood risks. Also, this research focuses on factors influencing local community trends and choices in the participation rate.

This study is applied research in terms of purpose and uses descriptive-analytical method. According to the nature of the study, data were collected through fieldwork and library research methods using observation, interview, questionnaire and evaluation card techniques. To understand different characteristics of community, Likert scale and one-sample t-test were used and measurement scale for data was ordinal. Also. The method of selective experimental approach based on profit was taken to evaluate the level of different trends in Community's financial participation for reducing detrimental effects of flood. To recognize the community awareness and perception toward flood risk and the probability of its occurrence in the future, the willingness level to participation and to explore the effective factors on villager’s decisions and to utilize modern management techniques the selective experimental approach based on evaluation card and logit model were employed.

The results of statistical analysis showed that in the study area, 86.5% of the community have experienced the damages caused by flooding and forecasted the likelihood of heightened chance of flooding in the future. Finding showed that although the people use traditional methods for managing flood, but they tend to employ modern methods such as dam building for reducing flood risk. This help them to increase the safety factor for their locations and farm lands. In spite of the fact that the villagers expressed the higher safety factor for new management methods such as (dam building, river broadening and preventing the destruction of forest and environment), but it seems that improper functioning, adverse consequences (environmental and socio-economic) of projects implementation (dam building) as well as the inability of villager's financial participation (high cost of this kind of methods), are barriers to using them for lowering the flood risks and damages.

The review of the possible role of some intervening variables to predict local communities' participation in decision-making processes showed that low-income, old age of the samples with high average (47.61) and education with lower average (3.16) are the most important factors influencing community decision making. The results of binominal logit model showed that the proposed variables is significant at the 5% level. If the offer price increase, the chance of residents' acceptance of participation will decrease and vice versa.


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.


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.


Hasan Mostafaii, Bohloul Alijani , Mohammad Saligheh,
Volume 2, Issue 4 (1-2016)
Abstract

Heavy and torrential rains are one of the hazardous phenomena of atmosphere which always cause several severe damages over Iran. For this reason in every developmental program their intensity and frequency should be understood and predicted. The main factor to their development and intensification are the atmospheric pressure patterns and motions. Therefore, in order to predict their occurrence, in this study we extracted the   highest daily precipitation of days with 90th percentile and above of the year for the 40 selected stations during the 1980- 2009 period. Of these days we selected the days in which at least 25 percent of the stations had the highest daily precipitation. For the selected days we extracted the 500 hPa and sea level pressure maps. Then we clustered the sea level

maps through the use of factor analysis and cluster analysis. We extracted five pressure patterns for the whole country explaining 77.63 percent of the total variation. In each pressure pattern we divided the daily rainfall intensity of its days by the daily intensity of all selected rainy days. In this way we developed an index which measures the share of each pressure pattern in the hazardous capacity of the country,s torrential rain days. 

   The results showed that during all of the torrential rain days there was a deep trough in the region between the Mediterranean Sea and Iran at the 500 hPa level which is accompanied with a low pressure center over Iran. The upper level trough brought the atmospheric instability and the low level pressure system brought the moisture from the western and southern water bodies and intensified the upper level instability. But the variations of their location and intensity caused different pressure patterns and rainfall intensities. Thus predicting the position and intensity of these pressure patterns are very important to monitor the torrential rainfall episodes of the country.

   The CP3 pattern with 30 percent of the days showed the highest during this pattern the western trough was bifurcated to the west of Iran but merged to the east. Thus tow maxima of intensive rain days were developed over the south and northwest of the country. The surface low center was deepened up to the northeast of the country bringing moister from the southern water bodies to the country. This pattern was dominant through the fall and winter seasons. The CP4 pattern with 12 percent frequency was the least occurring pattern. This pattern caused the heavy rains of the western parts of the country. The very deep trough to the west of Iran cause very heavy rains in the region. The CP1 pattern was strong in the north and northeast of the country where as the CP2 and CP5 patterns were dominated the southern parts of the country.


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).


Neda Kazemi, Maryam Sharifzadeh,
Volume 3, Issue 1 (4-2016)
Abstract

Frost is one of the sources of risk in agriculture which threatens the orchardists' performance and their security of products. The protection of cold-sensitive species of fruits against frost damage is an annual challenge in many growing regions of the world. Frost protection managerial behavior is the the first way to avoid or reduce the effects of frost damage to walnut trees. Application of active and passive methods of frost protection is effective under conditions of strong thermal inversions. However, most of studies on the adoption of managerial behaviors to environmental hazards usually ignore underlying psychological constructs that affect farmers’ decisions and behavior. Sepidan county is one the well-known regions of Fars province which is subjected to frost damage for its climatic nature. The amount of frost damage to walnut orchards of Komehr township, which is located in Northwest of Sepidan county is significantly substantial in recent years. The region is well-known for its walnuts and this product is the most important source of velliagers’ income. This research aims at investigating frost management behavior of walnut orchardists of Sepidan county, Fars province, Iran. The managerial behavior is composed of active and passive methods of protecting walnut trees to frost damage.

This applied study was based on descriptive correlational method. Data collection tools were structured questionnaires. The sample of this survey study was consisted of 90 orchardists of Komehr township. The sample orchardists were selected based on their vulnerability against frost. Structured questionnaires were used to collect information from a random sample of walnut orchardists that were interviewed. Face validity was confirmed by a panel of experts. And the reliability was confirmed by conducting a pilot study in Bardzard region. The calculated Cronbach’s alpha for the measures of the instrument were 0.53-0.82. Statistical package for social science (SPSS) in WINDOWS context was used for analyzing data. Coefficient of variation and cluster analysis was the most important analysis methods applied in this research.

Results revealed that active methods of frost protection includes burning fuel, tires etc., were the most common methods of controlling frost in walnut gardens. While using energy intensive practices (heaters, sprinklers) were shown the lowest rate of interest. However, orchardists' "perceived effectiveness", "perceived ease of use" and "perceived usefulness" of their active and passie controlling behavior was investigated. As it was shown by the results, orchardists' perception of effectiveness of the method of controlling frosts was in a low position. On the other words, they were not belived in the effectiveness of the methods. This was whilst, orchardists belived in ease of using the active and passive measures of controlling frost. They were noted that these methods had the potential of controlling damage to their gardens. Performing frost controlling methods was not easily applicable and garden's context was known as the most important barrier to performing the frost controlling behavior. To better understand orchardists' profile regarding to their frost protection behavior, cluter analysis was used. By means of this method, orchardists were categorized to two clusters: orchardists with convergent behavior with respect of frost protection protocol and divergent ones. Convergent group of orchardists (n=23, 25.5 %) were those who invested more on their gardens, used crop insurance supports, and more importantly they used lower levels of chemical products (poisons, fertilizers, etc.) on their gardens. On the other hand, divergent system of gardening regarding to frost protection pointed to the system of negative orientation towards rational thinking and behavior of gardening protection. These group of orchardist (n=67, 74.5%) were those who were performed eclologically dangerous methods of gardening regarding to use of pesticides, fertilizers and other chemical inputs. Low level of orientation towards crop insurance organizations and investment for the gardens were the most differtation factors for this group. However, results shed light on the difference of these two groups of orchardists regarding to their percievd effectiveness, ease of use and usefulness of frost protection methods. As it was shown by the results, frost protection- conevergent group of crchardists was significantly different from their divergent counterparts regarding their frost protection behavior and perception of ease of use and usefulness of frost protection methods. The aforementioned group of orchardists perceived frost protection methods easy to perform. From their viewpoints, these methods were useful in increasing crop yield, promoting its quality and controlling damge.      


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.



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