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Parviz Rezai, Khosrov Tajdari, Seyed Esmaeil Mirghasemi,
Volume 1, Issue 2 (7-2014)

Flood pron areas of rivers are generally hazardous. Regionalizing these hazardous areas in terms of the degree of hazard they produce is very important for regional flood management, insurance companies and land users. Therefore, this research has tried to regionalize the potential hazard of the flood prone areas of the Morghak River using HEC-GeoRAS model as an example for all flood plains of Gillan province.

    In order to develop the hydrolic model of the river, the following data were prepared.

  • The river profile, roughness index of the river channel and flood plain and river bank conditions were obtained from 1:2000 TIN maps.
  • The data were entered into the HEC-RAS model.
  • Then the data of the river banks and flood discharge amounts were entered and hydraulic computations were carried out.
  • The model results were entered into the GIS. After the requested processing in the extension of HEC-GeoRas431, the final maps of depth of river, water movement velocity, shear velocity and the flow intensity along the river channel were produced.
  • The maps were moved into the Google Earth and the flood area with different return periods were plotted.

    The results showed the areal expansion of the 25-year return period floods of the river basin. This plain is narrow in the upper areas of the river and widens in the lower areas of the area. In the areas that there are constructions, the basin gets wider and its higher discharges causes severe hazards in the settlements around the river. The widest part of the flood plain is over the lowlands around Anzali swamp. In these lowlands the flood spreads over the vast area and making problems for the farmers and dwellers.

    According to the results of this research some adaptation measures are needed in the areas where people have moved to the river channel and have built some structures. Some of these measures include vegetation planting, cement and rocky barriers and cleaning all extra wastes. The results of the study also indicate that in most of the branches the building of the channel has narrowed the channel and caused flood in the settled areas. The physiographic parameters of the river have seriously been changed and caused the severe floods in the river especially in the lower areas. The flow speed of the river changes from 4.1 m/s in the maximum discharge to .2 m/s in the very low discharge. The width of the channel has also changed from 281 meters in the maximum to 11 meters at the low discharge period. The discharge stress was between .3 to 357 newtons the overall results of the research indicate that the human interference in the river basin has caused all these hazards. And the only solution is that the humans should go out of the risky areas of the river basin. The continuation of this process in this river or in the other rivers will worsen the present hazards,

Omosalameh Babai Fini, Elahe Ghasemi, Ebrahim Fattahi,
Volume 1, Issue 3 (10-2014)

Global changes in extremes of the climatic variables that have been observed in recent decades can only be accounted anthropogenic, as well as natural changes. Factors are considered, and under enhanced greenhouse gas forcing the frequency of some of these extreme events is likely to change (IPCC, 2007 Alexander et al., 2007). Folland et al. (2001) showed that in some regions both temperature and precipitation extremes have already shown amplified responses to changes in mean values. Extreme climatic events, such as heat waves, floods and droughts, can have strong impact on society and ecosystems and are thus important to study (Moberg and Jones, 2005). Climate change is characterized by variations of climatic variables both in mean and extremes values, as well as in the shape of their statistical distribution (Toreti and Desiato, 2008) and knowledge of climate extremes is important for everyday life and plays a critical role in the development and in the management of emergency situations. Studying climate change using climate extremes is rather complex, and can be tackled using a set of suitable indices describing the extremes of the climatic variables.    The Expert Team on climate change detection, monitoring and indices, sponsored by WMO (World Meteorological Organization) Commission for Climatology (CCL) and the Climate Variability and Predictability project (CLIVAR), an international research program started in 1995 in the framework of the World Climate Research Programme, has developed a set of indices (Peterson et al., 2001) that represents a common guideline for regional analysis of climate.    It is widely conceived that with the increase of temperature, the water cycling process will be accelerated, which will possibly result in the increase of precipitation amount and intensity. Wang et al. (2008), show that many outputs from Global Climate Models (GCMs) indicate the possibility of substantial increases in the frequency and magnitude of extreme daily precipitation.     eneral circulation models (GCMs) are three-dimensional mathematical models based on principles of fluid dynamics, thermodynamics and radiative heat transfer. These are easily capable of simulating or forecasting present-future values of various climatic parameters. Output of GCMs can be used to analyze Extreme climate. For this study high quality time series data of key climate variables (daily rainfall totals and Maximum and minimum temperature) of 27 Synoptic stations were used across Iran from a network of meteorological stations in the country. In order to get a downscaled time series using a weather generator (LARS-WG), the daily precipitation output of HadCM3 GCM, SRES A2 and A1B scenario for 2011-2040 are estimated.     The Nine selected precipitation indices of ETCCDMI[1] core climate indices are used to assess changes in precipitation extremes and monitor their trends in Iran in the standard-normal period 1961–1990 and future (2011-2030).    Due to the purpose of this study, at first changes in extreme precipitation indices in the standard-normal period is evaluated and its results show annual maximum 1-day precipitation increased in many regions in the East of Iran. Simple measure of daily rainfall intensity (SDII), annual maximum consecutive 5-day precipitation, annual count of days with daily precipitation greater than 10mm (R10mm), annual count of days when rainfall is equal to or greater than 20 mm (R20mm) have increased in the central areas, regions in the north , north east and southern parts of Iran. Similar results are obtained for the R25mm index.    The consecutive dry days (CDD) index has generally increased across the west areas, southwest, north, northwest and southeast of Iran and indices of consecutive wet days (CWD) decreased in these areas.    Trends of extreme precipitation indices simulated by HadCM3 SRES A2 showing increases RX1Day in North West expect west Azerbaijan Province, central, southwest, north east and coasts of Caspian Sea. Similar results are obtained for the R5mm index expects northeast. There are mixed changes in R10mm across Iran, increasing in west, southwest, coasts of Caspian Sea, Hormozgan and Ardebil provinces, East Azerbaijan, Zanjan and Qazvin  provinces. Similar results are obtained for the R20, 25 mm index in northeast, south of Caspian Sea, and some parts in western and central areas. Same as HadCM3 SRES A2 pattern there are mixed changes in R10mm across the region. Positive trends are seen in part of the Isfahan, Markazi, Kuhkilue , Lorestan, Ilam, Chaharmahaland Khozestan provinces and some part of Hormozgan and Kerman and some areas in north west. Similar results are obtained for the R20mm and R25mm index and in west of Yazd to north of Khozestan provinces have increased.    Consecutive wet days (CWD) have increased over most of the west of Iran, Khorasn Razavi and Southern Khorasn provinces, In contrast consecutive dry days (CDD) index has generally increased in many parts of the region.  
[1]. Expert Team on Climate Change Detection and Monitoring Indices

Elham Ghasemifar, Somayeh Naserpour, Lyli Arezomandi,
Volume 4, Issue 2 (7-2017)

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.

Reza Reza Borna, Shahla Shahla Ghasemi, Farideh Farideh Asadian,
Volume 6, Issue 3 (9-2019)

Today, the impact of climate is considered on the life, health, comfort, activity and behavior in a form of the branch of science   such as human biology. Due to difference of frequency people with each other, the sensibility of every one from weather can be different from the other one that's why the climate can’t be totally undesirable or the climate can be totally desirable for all the people, so we can say that all of climatic elements are affected on human comfort but the effect of some of them is quite cleared and the effect of the others is mild and sometimes invisible. The greatest effect on comfort and discomfort can be included temperature, humidity and solar radiation. The aim of this research is to investigate and determine    the area risk of climatic comfort. For this purpose, the temperature, precipitation and humidity data have been extracted for Khuzestan province form Esfarazi database. In this approach, first different properties of the temperature, precipitation and humidity for the area with climatic discomfort   have discussed   based on the conditional probability distribution. This study has been identified the areas of climatic comfort in Khuestan province using multivariate analysis (Cluster analysis and Discriminant analysis) and spatial autocorrelation pattern (Hot Spot index and Moran index) with an emphasis on architecture. The results showed that the risk area of climate comfort is included mostly  of  the western parts of  Khuzestan province namely the border areas with Iraq and some parts of  southern  of  province .On the other hand ,trend analysis the  range of this area to climatic discomfort indicated that it has increased significantly  in  recent periods .The results also  showed that  the local distribution of   precipitation  in all periods in the areas of climatic discomfort  has  been   a high  the coefficient of  variations.
Mousa Kamanroodi, Moohamad Solemani, Mohamad Ghasemi,
Volume 6, Issue 4 (2-2020)


Ecologically-based Management Factors and criteria of River-Valleys in Tehran metropolis-Case Study: River-Valleys of Kan
Iran has seasonal rivers because of dry climate, low rainfall and different topography. These river- valleys have main role in forming, genesis, and sustainability of human settlements and provide different ecological services. The main services include beauty, store of green spaces, water supply, reduce and create temperature differences, local air flow and natural ventilation which are part of the functions. Tehran is roughly the same area as 730 square kilometers and its population is 8.7 million people. It is located in51° and 17´ to 51° and 33´ east longitude and 35° and 36´ to 35° and 44´ north latitude. The height of this city is 900 to 1800 meters. The north and north east of this city are located in peculiarity range of the southern part of the middle Alborz. This city includes 7 river valleys to the names Darabad, Golabdareh, Darband, Velenjak, Darakeh, Farahzad and Kan. The ecological role of these river valleys is reduced because of non- ecological axis developmental interventions by urban management and citizens. These interventions have changed river valleys to high risk space of skirt movements and flood. Kan is the most important river valley because of the breadth of the basin and permanent water discharge rate. The part of this river valley has changed to park (Javanmardan) by municipality. The purpose of this research is that to provide factors and criteria of ecosystem based management to organize this river valley.
ANP has been used in this research. To use this method for analyzing   factors and criteria of ecosystem based management to organize this river valley, firstly, these factors have been identified by library studies and scrolling. These factors include 4 criteria (natural: 15 sub criteria, social: 3, management:  6, economic: 2). the books, journals, reports, maps, aerial photos, satellite images and internet sites have been studied in library studies. In site studies, some information from library studies have been edited. After that, the findings of these two methods in form of questionnaire called factors and criteria of ecosystem based management to organize Kan River valley, was in charge academics and professionals. They were elected among pundits of urban management science, urban planning, geography and environment in Tehran. At first the number of them was 30 people came to agreement in two process about 4 factors and 18 criteria and determined importance and priority by Delphy method. Findings in Delphy method were analyzed through ANP and SUPER DECISIONS. In this process, firstly, a conceptual model and relation inter and intra clusters and nodes determined. These relations in this process are very important because paired comparison depends on this process. Assumption of equality of effects and similar relations in these factors is illogical because there are the grading of effects and relations in this research. Second, the factors have been compared to each other to create a super matrix based on paired comparison. Generally, in this process decision makers compare two different factors to each other and paired comparisons have grading of between1to9. In double- sided valuation, each factor is used to show initial inverse comparison. Inconsistent rate in paired comparison must be less than 0.1 like AHP. Third initial super matrix is created. It is the weights created from paired comparison and identified the importance of each factor in each cluster. Forth, the weighted super matrix was created. The weights of clusters was calculated in this process to identify the weight of final super matrix. Fifth, limited super matrix was created. The weighted super matrix reached for infinity band each row convergenced to a number and that number was the weight of factor. By this way limited super matrix was reached.
Based on ANP and table 1, management: 46%, natural – ecological: 26% and economic and social factors: 14% are important respectively in ecosystem based management to organize Kan River valley. Based on reached results, inconsistent rate is 0.003 and it shows that the weight is valid and review is not necessary. Among sub criteria in management factor, organizational pattern: 32%, method of management: 23% and policies: 21% are the most important respectively in ecosystem based management to organize Kan River valley. Among sub criteria in natural- ecological factor, flood, domain movements and building and texture of soil are the most important respectively 23%, 18% and 11.5% also in social factor, participation, security and public trust have the importance respectively equal to 49% 31% 19%. In economic factor, environmental assets and stakeholder’s economic participation have the same importance.
Based on this research, management factor (organizational pattern and the method of management) is the most important in ecosystem based management. But this approach, the management pattern and intervention to organize this river valley, need comprehensiveness and integrity of the subject (nature, society, management and economic), purpose (protection, resuscitation and use), factors (government, city council, municipality, private sector and people), duties (policy making, planning, designing and perform), method (collaborative), tools (knowledge, skill, rule, program, budget, machinery and materials) and management domain. Use of these factors and criteria need some infrastructure and reforms. The most important reform is reform of management structure, production of subject matter and topical program special to organize river valleys by ecological approach to release Kan of loading and contradictory this management can follow protection, resuscitation, sustainable use and continuity of ecological services.
Key words: ecosystem, ecosystem based management, analytic network process, river valley of Kan

Iraj Ghasemi, Fatemeh Razzzaghi Borkhani, Mohammad Ali Mohammadi Gharehghani, ,
Volume 7, Issue 2 (8-2020)

 Natural disasters and rural displacement: contexts and consequences in Balouch Abad village
Every year, a number of rural settlements are affected by natural disasters or human factors, in such a way that life in these settlements is dangerous, and even, in some cases impossible. Thus, displacement programs in the form of leaving the main settlement and creating new settlements in another place will be considered by planners and managers. These programs are not without consequences and affect different aspects of the residents' lives. Identifying these consequences can provide sufficient experience and evidence for managing other displacement projects. Accordingly, the current study focuses on displacement phenomenon in Balouch Abad village in order to identify the consequences of displacement by discovering the contexts of displacement and explaining the residents' perception about the causes of this phenomenon. In general, empirical literature on the topic shows that the consequences of displacement, both positive and negative, occur in all dimensions of human life, and that a change in any dimension can change other aspects of the life of the target community. Investigating all dimensions of displacement has been considered in a few studies, in which less attention has been paid to the existing contexts, perceptions and planning and management structures. Therefore, this study contributes to the relevant literature by querying these contexts and providing solutions for displacement programs in the future.
The aim of this study is to understand the perception of the residents of Baloch Abad village about the causes and consequences of residential displacement using a critical ethnographic approach. This approach is suitable for studying phenomena such as residential relocation, which are the result of the decisions of the planning system and in most cases is faced with the unwillingness and lack of interest of stakeholders (residents). In fact, the critical ethnographic approach seeks to examine inequality, conflict, and power in a subculture. Thus, the process of displacement due to integration with a kind of conflict between residents’ willingness and the planning system, can be well explained using this approach. Data was collected using in-depth interviewing, non-participant observation, and focus group techniques.
The experience of displacement in Balouch Abad village indicated that the consequences of displacement do not occur independently and are correlated with each other. In other words, the negative consequences in terms of social and economic are rooted in the physical- consequences, and on the other hand, the social consequences are also rooted in economic consequences. On this basis, the lack of attention to the proportion of housing based on social relations has been the prelude to occur other negative consequences. The mismatch between the structure and size of dwellings and their occupational requirements (animal husbandry) has led to the collapse of subsistence foundations. Evidence also showed that maintaining neighborly relations in the village was influenced by the physical structure and system of land transfer. As a result, it can be stated that the various consequences of residential displacement can occur through planning and physical management. This study is based solely on the evidence, contexts and perceptions of key stakeholders who are residents of Balouch Abad village; however, the part of the challenges of displacement in this village is due to managerial actions that were not considered in this study. Therefore, it seems that mere focus on the view of stakeholders is one of the main limitations of this study, which is necessary to pay attention to this limitation. In this regard, it has been tried to provide sufficient evidence on manures of management the displacement process through the technique of triangulation. Future studies may take into account the views of both experts and stakeholders at the same time.
Keywords: Residential displacement, Balouch Abad village, natural disaster, contexts and consequences of displacement.
Iraj Ghasemi, Sheida Ebrahimi Salimi,
Volume 7, Issue 4 (2-2021)

The development of the tourism industry, in addition to paying attention to the infrastructure of this industry, requires comprehensive planning of persuasive factors, as well as reducing the environmental and natural risks of tourism destinations. According to research, tourists are affected by four types of risks, including health, cultural, political and economic, but among the natural hazards that endanger the health of tourists is of particular importance.
 Among the tourist destinations, ecotourism has a significant success, which causes many hazards in these areas. Maranjab desert for the relative temperament of temperature, tourist attractions, diversity of animal species and vegetation, and the existence of typical and prominent forms of desert is one of the most visited areas of desert ecotourism. Therefore, many problems and dangers are threatening. In this research, an attempt has been made to identify and analyze the main natural and environmental hazards of the Maranjab desert with a descriptive-analytical method based on library and field studies.
The general approach of mixed-method with the priority of quantitative method is based on qualitative studies. For this purpose, after identifying the risks, a questionnaire for prioritization was collected through interviews with experts and then evaluated and analyzed through the FMEA technique. The method of FMEA is one of the tools for continuous improvement of product and service quality. The purpose of the FMEA is to identify the risks and risks of the product and process that may be latent or obvious. Once identified, the next step is to make decisions that can be addressed. This method is used in medicine, manufacturing and services industries. In recent years, the use of this model for risk assessment in the humanities and tourism has also become popular. This method is based on three key components of probability of occurrence, severity of occurrence and probability of discovery.
 After returning the questionnaires and evaluating the quality of response, a random sample of 100 questionnaires was selected and analyzed based on the method of analysis of failure factors and its effects. According to the purpose of the study, half of the audience had an individual trip and half of them traveled to the area with the group. Audiences were asked to assign a score between 1 and 10 for each component of the method. Accordingly, each factor will have a score in each case, which is obtained from the average score of the audience and has been between 1 and 10. After identifying and evaluating the risk perceived by the audience, in an interview with professors and

Iraj Ghasemi, Mohammad Ghasemi Siani,
Volume 8, Issue 1 (5-2021)

Spatial analysis of natural resilience in border areas
Case study: Zahak county
problem statement
Occurrence of natural disasters such as drought, floods and earthquakes in geographical areas, especially in rural areas, often have devastating effects. Hence, resilience has become doubly important, especially in special areas that are of special importance and sensitivity. On the other hand, border areas have a special place in policy-making and planning is important in this areas. One of these areas is Zahak county in Sistan and Balochestan province, which due to the instability and reduction of the inflow of river water resources, as well as climatic conditions and drought in combination with other factors, the traditional employment opportunities of the often rural population face serious challenges and therefore the county5b is deprived. Increasingly, the sustainability of livelihoods is facing problems. The question is, how do the spatial zones and the villages located in these zones react to the change of internal and external natural factors? Which areas and villages are more resilient?
Method of research
This article deals with the spatial analysis of environmental resilience in Zahak county and its purpose is to investigate the differences in resilience in different areas of the county. The general approach to the study is integrated and descriptive-analytical in terms of method. Data were collected using documentary and field methods with observation tools and questionnaires and findings of a specialized panel. The statistical population of this research is the villages of more than 20 households in Zahak city that have had governor of a rural district or village council.
Description and interpretation of results
The villages of Zahak county are threatened by the threat of these resources due to their dependence on natural resources. The results show that none of the defined geographical areas in the rural area is sustainable and three rural areas are semi-sustainable and one rural is unstable. Assessment of sustainability in micro zones also shows that naturally unstable villages are often sparsely populated, which means that activity has not developed either. After qualitative and quantitative evaluation of various natural and environmental indicators in the county and their impact on the resilience of places and settlements in the county, settlements and places in terms of resilience were classified into three levels of high, medium and low resilience. In total, 46.7% of settlements and places are at high level of resilience, 37% at medium level and 16.3% at low level of resilience. After matching the settlements and places with the geographical area of ​​the village, three of the four geographical areas are in transition and one is unstable. This study shows that the resilience of individual villages cannot perform well when it is located in areas surrounded by villages with low resilience and the whole area becomes unstable. Thus, in special areas such as Zahak county, crisis management should focus on providing natural resources and preventing vulnerability to natural crises, and it is expected that with natural stability, housing and activity will be sustainable.
Key word
Resilience, special areas, Zahak county, border areas, geographic zoning

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