نشریه تحلیل فضایی مخاطرات محیطی
سال چهارم شماره 2 (تابستان 1396)

Cyclones as the most important factor in the turbulence of mid-latitude regions are low pressure centers that have one or more closed Isobaric curves. Mid-latitude cyclones are responsible for transfer of the heat and moisture between the tropics and the polar regions. Mediterranean cyclones have the most important role in Iran's rainfalls and get from different tracks to the country and affect Northwest, West and South West of Iran in the cold period of the year. Cyclones are the prevailing weather phenomenon in Mid-latitude region and studying the characteristics and effects of these phenomena has always been of interest to climatologists and meteorologists. Iran which is located in mid-latitude region, actually is located in the path of one of the world's largest cyclone formation and the Mediterranean Sea has a main impact on the rainfall occurrence in Iran. Regarding the importance of cyclones in rainfall occurrence in Iran, especially in cold season, studying this atmospheric event seems very necessary.
The aim of this study, is to identify, tracking and analysis of the winter season (December, January and February or DJF) rain producing cyclones using special database and algorithm during three recently decades (1979-2009).
In this study, in order to specify, tracking and statistical analysis of the DJF rain producing cyclones, relative Vorticity of 700 hPa were received from ECMWF data center with AWT IMAGE spatial resolution and temporal resolutions of 6-hourly for a 30 years period (1979-2009). The study domain includes Mediterranean and Middle East, from AWT IMAGE E to AWT IMAGE E and AWT IMAGE N to AWT IMAGE N.
Cyclone identification will follow the approach presented in Blender et al. (1997) and Flaounas et al. (2014), including two important points and conditions: 1- A cyclone is considered to be a relative Vorticity extrema, thus the aim will be to look for the maximum value of relative Vorticity at the 700 hPa level in a box of AWT IMAGE grid points. 2. For the intensity of the cyclone, the threshold of relative Vorticity, is considered equal or greater than AWT IMAGE. Then by 6-hour tracking the maximum amount points of Vorticity and connecting them to each other, identification and routing of cyclone is implemented. The track AWT IMAGE can be written as AWT IMAGE, where AWT IMAGE describes the cyclone position in sequential time steps t = 0, … , T, which are given at 00, 06, 12 and 18 GMT. The initial position is considered the first detected maximum of relative Vorticity. During the cyclone detection and tracking method, different threshold values are commonly applied to eliminate, for instance, the weakest centers and short living systems. For this reason, the threshold of equal or greater than 8 time steps (3 days and more) is considered based on Alijani (1366) to eliminate short living cyclones.
In this study, climatology of cyclones such as genesis and lysis centers, tracks and frequencies in the Mediterranean Basin and Middle East were analyzed. The results showed that, center and eastern part of the Mediterranean region include Aegean Sea, Cyprus, and northern borders of Mediterranean Sea, Adriatic Sea and also Red Sea, Sudan and Iraq, are most important cyclogenesis centers in winter season.
These cyclones which form in these cyclogenesis centers, move to the east with two eastward and northeastward distinguished directions. In northwest of Iran, the cyclones by passing over West and East Azerbaijan and Ardebil provinces in eastward and northeastward directions, move into western and southern shores of Caspian Sea. In southwest of the country, the cyclones are entered into Iran over Khozestan, Chaharmahal and Kohkilouyeh provinces. Part the cyclones are moved into center and northeast of the country with northeastward direction and other part by crossing over southern shores of the country move to the southeast of the country. In mid-west of the country, the cyclones are arrived into Iran in three different tracks. The most important path is Kordestan's path which the cyclones in the origin of Mediterranean are entered eastward into Iran by crossing over Zanjan and Hamadan provinces, under the Alborz ranges are moved into east and northeast of the country. Two other paths are observed in Ilam and Kermanshah Provinces which in these tracks also the cyclones are approximately moved eastward into center and northeast of the country. The results also showed that eastern part of the Mediterranean region specially Cyprus, Aegean sea, Adriatic sea, Red sea and Sudan and also Iraq are most important wintertime cyclogenesis centers of Iran. The main entrance paths of the cyclones includes northwest, mid- west and southwest. The averages cyclones lifetime are 4.5 days, movement speed is about 20 km/h and also travelling length is about 1700 km. Of the other notable results we can refer to decreasing of the rain producing cyclones during 3 last decades.

Sustainable livelihoods approach as one of the new sustainable rural development approaches is one way of thinking and attempting to achieve development which arose in the late 1980s with the aim of progress and poverty alleviation in rural communities (Sojasi Ghidari et al.,2016).
Five critical concepts to understand sustainable livelihoods framework include the concept of vulnerability, livelihood assets, transforming structures and processes, livelihood strategies and livelihood outcomes (Motiee Langroodi et al,2012). According to the sustainable livelihoods framework, vulnerability is one of the fundamental concepts based on the vulnerability context (Forouzani et al.,2017). The vulnerability context forms the people's external environment. It comprises shocks (such as human, livestock or crop health shocks; natural hazards, like floods or earthquakes; economic shocks; conflicts in form of national or international wars) trends (such as demographic trends; resource trends; trends in governance), and seasonality (such as seasonality of prices, products or employment opportunities) and represents the part of the framework that is outside stakeholder’s control (Kollmair and Gamper, .(2002
Various research explored the factors influencing vulnerability and its dimensions and less research investigated to assess the vulnerability of rural households. Therefore, the purpose of this study is to investigate rural household's vulnerability in the Central District of Dena County. Accordingly, this research is to answer the following questions:What is the status of rural household's vulnerability to shocks?
What is the status of rural household's vulnerability to trends?
What is the status of rural household's vulnerability to seasonality?
The research method is applied in terms of purpose and non-experimental survey in terms of data collection. The statistical population of the study consisted of 2500 rural households in the Central District of Dena County, which according to Krejcie and Morgan table 300 households were selected using cluster random sampling.
The research tool for data collection was a structured and research-made questionnaire. Face validity was used in order to determine the validity of the questionnaire and the face validity of the research tool was confirmed by a panel of experts. A pre-test study was carried out in order to determine the reliability of the various sections of the questionnaire, Cronbach's alpha was calculated and reliability of the questionnaire was confirmed.
Vulnerability was measured using 20 questions and in three sections including shocks (8 items), trends (6 items) and seasonality (6 items) with a three-point Likert scale (low, medium and high) and SPSS software was used to analyze data.
The results of calculated vulnerability showed that the rural households had the most vulnerability to shocks including "causing damage to crops due to frost", "causing damage to crops due to drought" and "plant pests and diseases". In contrast, rural households had the lowest vulnerability to shocks including "family fights and ethnic conflict", "animal disease" and "illness of family members".
The respondents had the most vulnerability to the trends including "the rise in food prices and other life necessities" and "the rise in the price of energy carriers such as diesel, gasoline, etc.". In contrast, the respondents had the least vulnerability in trends including "gradual air pollution" and "increase in household's population".
The respondents had the most vulnerability to the seasonality including "lack of funds and capital in low working seasons" and "fluctuations in the prices of agricultural products". In contrast, the respondents had the least vulnerability to seasonality including "the impossibility of growing crops in different seasons" and "decrease and increase in the amount of agricultural production in different seasons".
The results showed that generally respondents’ vulnerability to shocks, trends and seasonality and the total vulnerability was at a medium level for the majority of the respondents (over 40%), at a high level for about 25 percent of the respondents, at a very high level for about 15 percent of the respondents and at a very low level for only about 10 percent of the respondents. Therefore, it could be concluded that more than half of the respondent's vulnerabilities was at a low and medium level.
Furthermore, in two groups with low and medium vulnerability, the average vulnerability to shocks, trends and seasonality are almost the same, whereas in two groups with high and very high vulnerability, the most vulnerability referred to seasonality, trends and shocks, respectively.
According to the research findings, the following suggestions are offered in order to reduce the vulnerability of rural households.
In order to reduce the vulnerability of rural households to shocks including "causing damage to crops due to frost", "causing damage to crops due to drought" and "plant pests and diseases", it is suggested that educational courses are held by the relevant organizations such as Agriculture Jihad in order to get familiar with ways to deal with damages caused by frost, drought and plant pests and disease. In addition, the use of heating system before the frost, the use of drought resistant varieties, the use of such techniques as land fallowing in order to reduce the need for water, the use of integrated pests management are offered as well in order to reduce the vulnerability of rural households.
Considering that the respondents had the most vulnerability to the trends including "the rise in food prices and other life necessities" and "the rise in the price of energy carriers such as diesel, gasoline, etc.", the rise in food prices as well as energy carriers in rural areas should be cautiously.
Founding loan fund in order to give loan and credit to households in low working seasons as well as determining a guaranteed price for agricultural products by the relevant authorities to reduce the volatility of agricultural prices are recommended.

Thunderstorms are among the first meteorological phenomena, which have attracted human attention. Thunderstorms with rain showers and storms accompanied by hail and their role in causing sudden floods, both in terms of agriculture and human and financial losses, have been noticed by researchers. Rain hail of bullets or pieces of ice ascends very high in elevation due to the weather conditions along with electrical features occurrence. Hail grains or pieces of ice with diameters of 5 to 50 mm occasionally take longer time to be made up. Strong growth of hail through severe and repeated vertical movements of air in cumulonimbus clouds freezes the absorbed water droplets around hailstones. Few thunderstorm hails arrive on land many of which even contain no hail even in the most suitable parts of the clouds. The creation and hail falling, despite being warm and humid in the lower atmosphere and the ascending of clouds condensed with respect to the altitude and cold weather are coupled with the continuing maximum air instability. Because of the importance of hail event, studies on the formation and growth of hail in different countries are conducted for its prediction. In connection with hail and hail storms extensive research work has been carried out in including: Costa et al. (2001), Simonov and Gergiev (2003), Whiteman (2003) and Sterling (2003).
To investigate the thunderstorm and hails occurred in the region, we examined weather conditions. Initially the values of pressure, temperature and dew point temperature by the radiosonde measurements in different layers of the atmosphere were studied and the plotted graphs were obtained from NOAA. In the next stage for a closer look at weather conditions parameters like air temperature (Air), sea level pressure (SLP), geo-potential height (Hgt), specific humidity (Shum), vertical velocity (Omega) orbital wind component (Uwnd) and meridional wind component (Vwnd) were analyzed. The data records were collected from the website of the National Center for Environmental Prediction and National Climate Science (NCEP/NCAR). Instability investigation in the atmosphere for different levels of instability indices was applied.
Investigation on instability indices showed that on the first day the ascending index values (LI) were at 2-, which are the values added in the next two days. These conditions prove that the atmospheric turbulence is intensified in the days after the first day. By examining the thickness of the atmosphere it is seen on the Azerbaijan area On 16 July that on 5785 geo-potential meters the next day was associated with reduced 51 meter geo-potential added value at the third day. The results also revealed that the atmospheric precipitation of water values is calculated on a three-day index value of 17, 18 and more than 23 mm per day. To check the status of stormy weather index (SWEA) and K we found that the occurrence of thunderstorms in that area started on 16 July, approaching the end of high value added indicators that show strengthening of storms and their destructive mechanism in the day after the end of the other.
Investigation of thermodynamic charts showed that rapid convective ascent of available potential energy depending on the weather in the region has been so high and caused the weather to approach three days in advance to the upper layers of the atmosphere and atmospheric turbulence was created for the region. Examining the rainfall map of geo-potential height and vortices in 500 hPa on the first day exhibited that tthunderstorms were the result of interactions of the atmosphere, so that in middle levels the strong condensation of location with a range of more than 25 degrees of latitude on Caspian Sea was created and polar latitudes spread to nearby areas. On the second day, high-altitude thunderstorm in the core atmospheric cut-off formed on the Caspian Sea on the East of Turkey, northern Iraq and North West of Iran created the geo-potential height of the center of the 5750 geopotential meter. On the third day, atmospheric cut-off core to cut area of low pressure was made on the maximum positive vortices in the climate system. Conditions over the surface in the first day of the storm in the region indicated very strong contour of low pressure formed in the North East to West and North West of Saudi Arabia. In front of the two sides one of on Mediterranean Sea and other northern Russia, the contour of the pressure was imported into the Middle East.

In the recent years there has been attention on the management of dangerous wastes because of their incremental growth, since ignorance toward this problem will result in numerous environmental, social and economical problems. Finding an optimized place for the urban and rural waste burial, with least environmental danger and economical optimality is one of the main objectives of this paper. In the presented study, the research method and the type of practical research is description-analysis and for data gathering, we used the library and athletic studies. The data analysis has been done by a scoring method (5-0) and the web analysis method which is a multi-objective decision-making method. Since in the ANP method the qualitative and quantitative factors and the correlation of the factors have been taken into account, we used social, economical and environmental factors for evaluation of the waste burial centers and their impacts on the towns and villages of the Zanjan province. The process of evaluation of the optimal waste burial centers is done in some stages including preparation of distance maps, prioritizing from the importance point of view using the geographical information system technologies (GIS), determination of the weights and at last, merging the resulted maps using the ANP method. The research results show that the prioritized regions in the map are based on the waste burial places. Based on this method, the 5th priority in the maps and especially in the final map shows the most suitable place and the 1th priority shows the least value and the 0 priority has no value for the waste burial places.

Precipitation is not only a critical process in global hydrologic cycle but also an important indicator of climate change (Fu et al.,2016). Precipitation is a key factor of the global water cycle and affects all aspects of human life. Because of its great importance and its high spatial and temporal variability (Thies and Bendix.,2011). Climate change is caused many extreme climatic occurrences in recent decades. One of most important extreme events is extreme precipitation. The changes of temporal-spatial patterns of precipitation may potentially cause severe droughts or flood hazards (Jiang et al., 2008). There are many environmental damages which are related to these events. Precipitation events were examined and studied by many researchers. The purpose of the study is evaluating of the structure and origin of the events in the west of Iran. Studies about extereme precipitation is somewhat strong. Robert, 1993 evaluated many flashflood in United States which is related to short wave at 500 hgt level. Many researchers also studied this type of precipitation such as Kumar, 2008 and etc. Trend analysis is another approach is related to this scope. Globally, precipitation increases in equatorial rain bands; decreases in subtropics as greater tropical convection in the rising branch of the Hadley circulation will lead to enhanced subsidence in the subtropics; and increases in high-latitudes due to increase in moisture transport (Huang et al., 2013). Synoptic analysis of the events is required due to increseing trend of this events and tremendous socioeconomic impacts on many places. First, a 99 percentile for recognition of extereme precipitation is applied for daily precipitation during 2000-2015 at seven weather stations in the west of Iran. Then principal component analysis carried out in order to reduce correlated data (SLP, hgt at 500and 850level) which is associated to synoptic patterns. Two extereme precipitations are selected for synoptic analyses. In order to better perspective of these patterns analyses are performed using sea level pressure, 500 and 800 hgt level, omega, u-wind, V-wind, relative humidity, and TRMM precipitation Radar data. TRMM data is used due to satellite systems provide a unique opportunity to monitor Earth-atmosphere system processes and parameters continuously and the correct spatio-temporal detection and quantification of precipitation has been one of the main goals of meteorological satellite missions (Thies and Bendix.,2011).
The results of precipitation data showed extereme precipitation dates based on 99 percentile are as fallows during 2000-2015 time period: 29 Jan 2013, 30 Nov 2008 , 3 and 4 feb 2006, 25 Dec 2004, 13 jan 2004, 1 dec 2001, 24 mar 2000, 2 may 2010, 29 and 30 Oct 2015. After identitying extereme precipitations, PCA (principal component analysis) applied for SLP data, Geopotential hight at 500 and 850 levels data in oredr to recognition the synoptic patterns. The results indicate that there is only one component which explains 99 percent of variances of data. Therefore the one synoptic pattern incorporated in formation of extereme precipitation in the west of Iran. Then for better understanding of this pattern, we are selected two extereme precipitation reanalysis data (29 oct 2015) and (13 Jan 2004) and evaluated sea level pressure, 500 and 800 hgt level, omega, u-wind, V-wind, relative humidity, and TRMM precipitation Radar data in these dates. The purpose of this proccess was monitoring different parameter in two dates. The results illustrated interesting conditions which is related only to providing appropraite condition for extereme precipitation formation. Many conditions required to the events as fallows: SLP lower than 1000 hpa over the west of Iran, surface relative humidity larger than 70 percent, negative omega lower than -0.3, positive vortices which indicate cyclogenesis. Another most important factor which caused extereme precipitation is location of trough. In all cases, the western of Iran located in front of trough at 500 and 850 hpa. The Precipitation Radar of TRMM satellite also determined same precipitation patterns which are specific for the west of Iran. This is only one part of the heavy precipitation studies at west of Iran the authours sugesst climate change studies such as trend analysis in a long time period, simulation with regional models as Regcm and WRF, appling ERA-interim data which can provide fine spatial resolution up to 0.25 degree over study area which need to be done in order to completion of the results.

Human settlements as local -spatial systems are subject to continuous dynamism and transformation. In the meantime, rural settlements including; in Iran, as the most important establishment of population and activity, are exposed to the deepest environmental, ecological, social, economic and cultural changes. It is evident that in these developments, a variety of different and different forms of internal and external interactions Are creative However, most of these factors are somehow influenced by the management system that plays a role in the rural areas. This system, having different patterns, has a different effect on spatial systems.
The issue of drought has recently been the major concern all over the country and particularly in Urmia Basin. This is considered as a key factor in Urmia Lake crisis. Urmia's rural settlements are also affected by the management factor in a variety of spatial dimensions. The crisis of the dramatic decrease in Urmia Lake water and its management (decisions making) has posed a serious challenge to rural areas. This article to pursue to base management as a foreign factor on the basis of a good governance approach to the analysis and analysis of the role It focuses on the transformation of rural settlements in Urmia.
This research is applied in terms of its purpose and based on descriptive-analytical method. The statistical population of the study was the experts in the institutions related to the county crisis management. Experts from sample target communities were 70 people who were identified by a sample size determination method with an unknown community. A sample sampling method was used to select the samples. Data and information was collected using library and information technology. The questionnaire was used to assess the role of the management system in the framework of the components of a good governance approach and Referring to related research backgrounds, they were identified. To measure the normal distribution of data and appropriate regression selection, Kolmogorov-Smirnov and Dorbin Watson's tests were used. Also, for measuring the direct and indirect effects and the correlation between the components, Pearson's path analysis and Pearson correlation tests were used in SPSS software.
The findings of the research shows that the villages affected by the disaster management system in facing the risk of drying the Lake Urmia have encountered inappropriate environmental, social, economic and physical changes. These changes are influenced by the military mechanism that It is not due to being state-owned, focused, and open-minded; they are not accountable, legitimate, and efficient. In the meantime, the weakness of the legitimacy of failure in effective performance has had a direct impact on the disaster management inefficiency. Of course, other components such as weakness of pivotal justice, weakness of accountability, weakness of orientation affect the components of the weakness of legitimacy and weakness of the role Effectiveness has doubled disaster management inefficiencies.
The assessment of the disaster management system of Lake Urmia, based on the governance framework, indicates that the management system has not been efficient. This ineffectiveness, however, is heavily influenced by the weakness of legitimacy. But, indirectly influenced by other factors, including weakness of orientation, weakness of justice, and weakness of accountability. The important thing in this regard is the impact of the indirect factors on the legitimacy factor. By considering the nature of their direct and indirect factors, it is clear that the weak role of the villagers and the means to participate in disaster management, the cause of all problems In the countryside. Restoring Lake Urmia without paying attention to the villagers living around the Lake Urmia will be difficult. Therefore, giving villagers the role of the main beneficiaries of Lake Urmia Basin can help restore Lake Urmia.infact,Communities are the first responders in case of a disaster. Therefore, community-based disaster risk management should be the core of any risk reduction approach. community based Disaster risk management focuses more on community participation and reducing underlying risk, encouraging preventive action before a disaster. and focuses on participation on design, decision and performance for better management of disasters.

Natural hazards are basically the changes that occur in environmental conditions, causing a disruption of the natural life of the people and their exposure to hazardous and degradable elements and elements. Establishing cities and residential areas on landforms has created new perspectives. The development of these areas has altered the geostationary balance of many landforms, and the response of geosystems is an expression of geomorphological hazards such as land subsidence, fault activity, flood, and the like that threatens residents of urban areas. The trend of population growth in the urban areas of Lorestan province in western Iran has also caused the physical expansion of the provincial cities in the periphery. This development has resulted in landslides and areas that, in many cases, have not been studied in environmental and environmental sustainability. The consequence of this is to increase the risk factor of these areas against a variety of hazards. In this regard, the aim of this study is to analyze the geomorphic hazards of earthquake, flood, landslide and liquefaction in the 9 major cities of the province and zonation of areas based on the degree of risk, in order to identify the high risk areas, urban management, necessary measures to increase environmental capabilities. And reduce vulnerabilities
In this research, effective factors were first identified in the occurrence of each of the flood geomorphic hazards, landslide, earthquake and fluidization. Then, maps were prepared for each of the factors, topographic maps, geology, geological data, seismicity, etc. from different organizations and maps were prepared. After preparing the maps, the fuzzy standardization method (decreasing and incremental functions) was used to determine the effective impact of each of the effective information layers in the occurrence of each of the hazards. In the final stage, considering the factors affecting the occurrence of any geomorphic hazards, weighing to layers based on their degree of importance was carried out using (AHP) method. At this stage, the final weight of each layer was multiplied in the corresponding layer, and then together and the final map of each of the geomorphic hazards was prepared. After mapping each of the geomorphic hazards of the studied cities, weighing and combining earthquake, flood, landslide and fluidization layers, maps of geomorphic maps of the cities were prepared.
The study of the geomorphic hazards of the city of Poldokhtar in the south of the province suggests that flood occurrence is considered as the most important threat to the geomorphic city of Poldokhtar. There is also a possibility of liquefaction due to the high groundwater level, especially in the north of the city. In the city of Kohdasht, in the west of the province, the risk of flood events is higher than the other hazards due to the river passing as a drainage of the catchment from the city. Geomorphic hazards in the northern city of northern Lorestan indicate that the central part of the city is at risk of landslide and liquefaction and parts of the north, west and south are exposed to flood. The probability of occurrence of geomorphic hazards in the area of Alshatr in the north of Lorestan province is low. So that the northwest and eastern parts of the city are risk free and in other parts, the risk of geomorphic hazards is moderate and low. Surveying the risks of Boroujerd city indicates that parts of the West of the city that are in high risk of flood, landslide and liquefaction are known as high risk areas and southern regions as low risk areas. Also, among the threats of Borujerd city, the probability of an earthquake due to the crossing of the young Zagros fault from the Silakhor plain is more than the other geomorphic hazards. In the city of Azna, the risk of flooding is considered to be the most significant danger to the city, although there is a likelihood of landslide and fluidization. The study of geomorphic hazards in the city of Aligudarz shows that rivers in the west of the city are exposed to geomorphic hazards, especially flood. In the city of Dorood, the flood event seems more likely than other hazards. The flood event in the central part of the city, which crosses the main rivers, has the highest potential. But in general, the risk of an earthquake is the most important geopolitical risk in the city of Dorood. In the city of Khorramabad as the capital of Lorestan province, the southern parts of the city have the highest geomorphic risk due to the high potential of flood and liquefaction. Also, the flood risk is considered to be the most important geomorphic risk in the city.
The study of geomorphic hazards in the major cities of Lorestan province suggests that there is a probability of occurrence of hazards in urban areas, but the types of hazards are different in cities located in the west and east of the province. Studies show that there is a potential for flood events in many cities, especially in southern cities and Khorramabad, in the capital of the province. Cities located in the east of the province (Doroud, Azna and Boroujerd) have a high density of earthquake occurrence due to the fact that they are located in the zone of the young Zagros fault and the Seychelles seismic quake. Nevertheless, according to geological formations, there is a possibility of landslide occurrence in the cities of Khorramabad and Aligudarz. The likelihood of occurrence of liquefaction occurrence in the studied cities is higher, especially in the eastern province of the province, because the urban areas are mainly located in plains with high groundwater and alluvial soils. The final results show that the risk of flood in the western regions of Lorestan province and the earthquake in the eastern provinces of the province are the most important threats to geomorphic cities.