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Bohloul Alijani,
Volume 1, Issue 1 (4-2014)

Environmental hazards include all kinds of hazards in the environment such as natural and technological or natural and man-made. The natural phenomena such as rains or floods are the normal behaviors of the nature which only when they cause damage to the human life, are considered as hazard. The technological events such as road accidents, air pollution and chemical pesticides are always dangerous to human life. Both kinds of two hazards are produced in the context of human- nature relation. For example if human beings avoid flood prone areas there will be no harm or damage. And if human beings control their waste in the urban areas they will never pollute the city. Thus, this is the human who causes risk and damage to his life. The relation between human and the nature is governed by the thoughts and beliefs of human or in general terms his world perspective and philosophy. It is the human perspective and belief which controls his action at any circumstances. A person who believes in the nature as his mother and supporter of life differs from the one who thinks of nature as a sole source to use and enjoy. The first one gets only his basic needs from the environment, but the second person tries his best to exploit the nature for his benefits. Therefore to understand the intensity and frequency of environmental hazards, we should investigate the mental beliefs of people living in different places. A brief discussion of the historical development of hazards will help us to have a better understanding of the philosophical basis of the environmental hazards. From the ancient times up to around nineteenth century life was very simple and man had been using nature only for his basic needs, there was no consideration of environmental hazards. Hazards were considered only as diseases threatening the human life. But later, especially after the industrial revolution, due to the increase of human population and demands, the use of natural resources was exponentially increased far above the production and recovery of the nature. This process triggered the occurrence and expansion of environmental hazards.  The human- nature relation is studied by different scientific fields such ecology, anthropology, and geography from different aspects. The ecologists mostly emphasize on the relationship of individuals with his environment, as the characteristics of environment controls his life. While geography studies the spatial relations between human population and environmental assets. As a result, the philosophical stances of these fields differ substantially. Ecologists want to see whether this relation is dominated by the needs and intentions of man or by the capacity and potentials of the nature. From this point of view three kinds of philosophies were developed including anthropocentrism, biocentrism and ecocentrism. On the other side, geography emphasizes on the spatial distribution of human population on the basis of environmental resources. This spatial relation between human and natural resources is believed to be controlled by the nature or human conducing to the development of two philosophies of environmental determinism and possiblism. Ecological philosophy of anthropocentrism was dominated in the earlier centuries, focusing on the will of human to use and enjoy the nature. In this view, the nature has the instrumental value for human. The result of this philosophy was depletion and destruction of the environment in favor of the human development. But during the twentieth century some philosophers stated that the human does not have the right to harm and damage all living creatures including animals and plants. This view ended with the biocentrism approach.  During the second half of the 20th century due to the over exploitation of nature by human, the philosophers and ecologists realized that the human kind in order to possess a sustainable living should not harm any members of the environmental system including even rocks, rivers, soil and etc. This approach developed the ecocentrism philosophy. The main controlling force in these philosophies is the ethical stance of humans. On the other hand, the older geographers believed that it is the nature that controls the human distribution and living conditions. The humans cannot change the natural arrangement of the environment and should limit their activities to the natural allowances. The development of the technology after the Second World War changed this view. Some geographers believed that human can change the environment by his techniques and developed the possiblism. The adoption of this philosophy and the growth of industrial development ended with the deployment and damage of the natural resources. It is clear from the aforementioned discussion that in all cases, the main reason for the depletion and destroy of the environment was lack of ethical considerations in human behavior toward the nature. If the ecologists have come with the ecocentrism, geographers developed the geocentrism philosophy. That is, to save the nature and prevent environmental hazards we, as human beings, should preserve the natural arrangement of resources. We should not disrupt the spatial order of any resources, because it will cause harmful results in the environment. For example eroding the soil will deteriorate the vegetation and cause floods and other hazards. The alteration of spatial order of surface temperature has caused the thermal imbalance and hence global disorder and warming. There is no doubt that the relation of each human should be controlled and put in the moral contexts, but to prevent the environmental hazards an overall effort is needed over the environment which is possible only through the preservation of spatial order of natural resources. Spatial management of land resources is the outstanding example of this philosophy and ethic.

Bohloul Alijani, Bahram Molazadeh, Mohammad Saligheh, Mohammad Hossein Nassrzadeh,
Volume 1, Issue 4 (1-2015)

Climate is one of the important natural factors that affect all stages of life, particularly human exploitation. Selection of the type of clothing, housing, cultures, architecture, civil engineering, and settlements are influenced by climatic factors. It can be said that the climatic circumstances of the surface of the earth and atmospheric circulation patterns have an important role in shaping and organizing the environment (Alijani, 2009). In some cases, the normal weather conditions become abnormal and cause many damages, which are mostly catastrophes rooted in climatic changes, such as hail, frost, heat and cold waves, floods, storms and so on. Blizzard is one of the atmospheric phenomena, which happens as the result of snow combined with wind (15 meters per second), and low temperatures (below zero°C), and it causes severe losses.

Due to its special geographical location, Iran is placed in the transition region of the large-scale patterns of common tropospheric circulation, and is the intersectional place of the of extra-tropical and tropical circulation system. This feature along with its complex topography caused the land to have a considerable climatic diversity. The climatic diversity makes the various climatic phenomena to be observed with intensity, energy, and different frequencies, therefore, the climatic phenomena with high intensity always causes damage to natural resources and the human civilization. This undesirable phenomenon is called climatic risks. Since the West Azerbaijan Province is located in mountainous areas and high latitudes, the feature is triggered many climatic risks such as flood, hail, snow, snow storm, and so on. Therefore, snowstorm is one of such phenomena that have occurred every year or every few years due to the specific characteristics of the region and have caused damages in the fields of transportation, energy, livestock, closeness of schools and offices.

The purpose of this study is the statistical and synoptic analysis of snowstorm in west Azerbaijan province. Therefore, the data related to the present weather codes were collected during the period 1986 to 2009 from the National Meteorological Agency. The data related to the weather codes entered in Excel, and data related to the snowstorm were selected through Filter tool and isolation of codes related to the strong snowstorms (codes 37and39) and weak snowstorms (codes 36 and 38). Then the data related to the snowstorm was entered in SPSS, and the statistical analysis was performed. In the next step, three cases of the strong and common snowstorm (code 37 and 39) were selected for synoptic analysis. Then, the synoptic maps of the different layers of the atmosphere were selected as the samples for strong snowstorm for the days before the event of the phenomenon, the day of event, and the day after the event of the phenomenon by the using of the accuracy of 2.5 degrees from website. The study area has been selected in 10 to 80 degrees north latitude, and 15 to 90 degrees east longitude for identifying the patterns that affect West Azerbaijan Province. The data was received on wind speed and direction in digits from the National Center for Environmental Prediction. Then, the maps of the wind direction and speed were provided in Grads. Finally, the daily analysis and interpretation of pressure (500hPa at sea level), instability (700hPa level and the ground level), Earth's surface temperature, wind speed and direction maps for 700hPa level, and identification of patterns that have caused snowstorm in West Azerbaijan province were carried out. Statistical and synoptic analysis of snowstorm phenomenon in West Azerbaijan province during was performed in the period 1986 to 2009. To do this, using codes 36 to 39, which represent a variety of snowstorm (weak and strong), the frequency of snowstorm days on monthly and annual average, distribution of the snowstorm in the extracted stations, the frequency of strong snowstorms (codes 37and39), weak snowstorms (codes 36 and 38), all types of snowstorms (codes 36 to 39), and the frequency of storms in the station level were compared. Out of 322 snowstorms occurred during the period 1986 to 2009 in seven synoptic stations 108 have been determined as strong snowstorm and 214 as weak snowstorm. In order to analyze the synoptic snowstorm in West Azerbaijan province, in the first place, the strong snowstorms were identified, and then five of the strong and comprehensive storms were selected for the synoptic analysis. The snowstorms of choice are as follows: On 18 January 1986, on January 19, 2000, on February 7, 1992, on February 5, 1997, and on December 25, 1990.

For applying the study, pressure maps, Omega (700hp level at ground level), Earth's surface temperature, and wind speed and direction at 700hPa were analyzed, and patterns and conditions that are causing this phenomenon in the West Azerbaijan province were identified.

      In this study, to perform statistical and synoptic analysis of snowstorm in Western Azerbaijan province, the statistical data were examined during the period 1986 to 2009 from 7 stations, and the results of the statistical analysis showed that:

• Out of a total 322 snowstorm event days of 7 synoptic stations during the period 1986 to 2009, 108 and 214 days were strong and weak snowstorms, respectively.

• Review the annual and monthly snowstorm during the study period showed that the 1992, 1997, and 1989 with a total of 69, 29, and 25 days, as well as the 1999, 2006 and 2007 with 0, 1, and 1 day have the most and the fewest days of snowstorm, respectively. The statistical analysis showed that the snowstorm phenomena happened in January, February, March, April, November, and December. January had the most and April had the fewest snowstorms with 119 and 3 days, respectively. February with 39 days, and April and November, with the number 0 and 1 had the most and the fewest days of strong and constant snowstorms.

• Distribution of the snowstorms in the stations indicated that out of the studied seven synoptic stations, which had a great impact on the synoptic situation of the region, topography, and height, Sardasht-Maku station had the most, and stations of Khoy, Mahabad, and Orumiyeh by having no snowstorms had the fewest days of snowstorm.

• The results of the maps of the different levels of the atmosphere and Earth’s surface in the days before the storm, event day and the day after the snowstorm were selected for the snowstorm pattern, which indicated that the snowstorm in the winter due to low compliance pressure formed in the earth's surface with synoptic patterns of middle levels of the atmosphere have provided the conditions for the event, in a way that among the sample cases of the strong snowstorms occurred in the West Azerbaijan Province two circulation patterns were involved in the formation of natural hazards: The Caspian Sea low pressure pattern- Eastern Europe high pressure pattern and the north of the Black Sea low pressure pattern.

Fatemeh Sotodeh, Bohloul Alijani,
Volume 2, Issue 1 (4-2015)

Precipitation is one of the important aspects of the Earth’s climate that has both spatial and temporal variations. Understanding the behavior of this element and analyzing its spatial and temporal variation is importantwhich can lead to a comprehensive and detailed planning for water resource management and agriculture. Geostatistical techniques and spatial autocorrelation analysis are the most widely used techniques in the field of the spatial continuity. Spatial autocorrelation analysis is applied to help researchers understand the spatial patterns in the area.

      The purpose of this study is to identify the heavy precipitation spatial patterns in Guilan Province. For this purpose, the 6- hourly sea level pressure of the network from  0 to 120 Easter longitude and 0 to 80 Northern latitude with 2.5×2.5 degrees spatial resolution were obtained from the National Center for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) for the period 1979-2010. The daily precipitation data of 21 stations were obtained from the Islamic Republic of Iran Meteorological Organization and Ministry of Energy.

      Guilan province is one of the most humid regions in the country. The heavy rain days were selected as days when more than 30 percent of the all stations had daily rain amount more the 95th percentile. As a result, 321 days were selected as heavy and widespread rainy days. By using principal component analysis these 321 days were reduced to 9 factors. These factors then were subject to cluster analysis with Ward method and resulted in three surface pressure patterns of heavy rainy days. Within the resulted pressure patterns by using local geostatistical techniques we identified the heavy rain spots and their spatial orientation. These spatial methods include Kriging,  Geostatistical Analysis, and Anselin local Moran index.

According to the results of this research, the first pattern was characterized with a high pressure over northern part of the Black Sea causing the highest Variance of heavy rainfalls. The second pattern is identified as a low pressure on the Black Sea. But the third pattern showed a precipitation distribution with low variation caused by the Siberian high-pressure. The results of Spatial Statistics techniques indicated that heavy rains were clustered in all there patterns. The clusters of heavy rains were localized mostly over the coastal areas and some over the central regions. The clusters of the western high-pressure patterns penetrated somewhat inside the province, while clusters of the Siberian high pressures was located on the shoreline of the province. The precipitation of western migratory high-pressures was heavier than of the Siberian high-pressure. The results of the standard deviation ellipse showed that heavy rain clusters were oriented in the east-west direction and were nonhomogeneous. While the ones oriented in the south east direction were more homogeneous and clustered. Because of this arrangement, the entry of moisture from the Caspian Sea is relatively concentrated on the East or North East. Because of the concentration of heavy rains in the central areas of the coast, the risks of floods and soil erosion is very high in these areas. This study showed that contrary to the popular belief, the heavy rains of Guilan were produced by western systems and the role of the Siberian high pressure is less important and is limited only to the coastline.

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

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.

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

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.

Tofigh Saadi, Bohloul Alijani, Ali Reza Massah Bavani, Mehry Akbary,
Volume 3, Issue 3 (10-2016)

Understanding the changes in extreme precipitation over a region is very important for adaptation strategies to climate change. One of the most important topics in this field is detection and attribution of climate change. Over the past two decades, there has been an increasing interest for scientists, engineers and policy makers to study about the effects of external forcing to the climatic variables and associated natural resources and human systems and whether such effects have surpassed the influence of the climate’s natural internal variability. The definitions used in the 5th assessment report were taken from the IPCC guidance paper on detection and attribution, and were stated as follows: “Detection of change is defined as the process of demonstrating that climate or a system affected by climate has changed in some defined statistical sense without providing a reason for that change. An identified change is detected in observations if its likelihood of occurrence by chance due to internal variability alone is determined to be small.  Attribution is defined as the process of evaluating the relative contributions of multiple causal factors to a change or event with an assignment of statistical confidence”. Detection and attribution of human-induced climate change provide a formal tool to decipher the complex causes of climate change. In this study the optimal fingerprinting detection and attribution have been attempted to investigate the changes in the annual maximum of daily precipitation and the annual maximum of 5-day consecutive precipitation amount over the southwest of Iran.

This is achieved through the use of the Asian Precipitation—Highly Resolved Observational Data Integration Towards Evaluation of Water Resources Project(APHRODITE) dataset as observation, a climate model runs and the standard optimal fingerprint method. To evaluate the response of climate to external forcing and to estimate the internal variability of the climate system from pre-industrial runs, the Norwegian Climate Center’s Earth System Model- NorESM1-M was used. We used up scaling to remap both grid data of observations and simulations to a large pixel. This remapped pixel coverages the area of the southwest of Iran. The optimal finger printing method needs standardized values like probability index(PI) or anomalies as input data, since the magnitude of precipitation varied highly from one region to another. The General Extreme Value distribution (GEV) is used to convert time series of the Rx1day and Rx5day into corresponding time series of PI.  Then we calculated non-overlapping 5-year mean PI time series over the area study. In this research, we applied optimal fingerprinting method by using empirical orthogonal functions.  The implementation of optimal fingerprinting often involves projecting onto k leading EOFs in order to decrease the dimension of the data and improve the estimate of internal climate variability. A residual consistency test used to check if the estimated residuals in regression algorithm are consistent with the assumed internal climate variability. Indeed, as the covariance matrix of internal variability is assumed to be known in these statistical models, it is important to check whether the inferred residuals are consistent with it; such that they are a typical realization of such variability. If this test is passed, the overall statistical model can be considered suitable.

Results obtained for response to anthropogenic and natural forcing combined forcing (ALL) for Rx1day and Rx5day show that scaling factors are significantly greater than zero and consistent with unit. These results indicate that the simulated ALL response is consistent with Rx1day observed changes. Also, it is found that the changes in observed extreme precipitation during 1951-2005 lie outside the range that is expected from natural internal variability of climate alone and greenhouse gasses alone, based on NorESM1-M climate model. Such changes are consistent with those expected from anthropogenic forcing alone. The detection results are sensitive to EOFs. We estimate the anthropogenic and natural forcing combined attributable change in PI over 1951–2005 to be 1.64% [0.18%, 3.1%, >90% confidence interval] for RX1day and 2.5% [1%,4%] for RX5day.

Morteza Esmailnejad, Bohlol Alijani,
Volume 4, Issue 1 (4-2017)

Climate change is one of the crucial factors, which threaten many sector such as agriculture, water resource for decades, and the sector is more sensitive to climatic conditions.  Communities are the most vulnerable to the adverse impacts of climate change and variability because of their low adaptive capacity. One of the challenges of climate change and human spatial dimensions of climate change in international borders where climate change, and creates special challenges. Populated places in the East where rapid urbanization, industrialization and agricultural intensification result in vulnerability to climate change, water shortages as the main concern arises.

 Adaptation to climate change is the adjustment of a natural or human system to moderate the impacts of climate change, to take advantage of new opportunities or to cope with the consequences. Trying to identify the attitudes of people and their mental models of climate change can provide application to manage the post-change. Culture and engineering modeling approaches minds of scientists for climate risk management and climate change consequences have adopted. The review focused on farmers’ perceptions on changes in temperature, precipitation (rainfall), adaptation measures taken by farmers, barriers inhibiting these adaptation measures and the socioeconomic determinants of adaptations to climate change in Sistan plain.

The aim of this study is to provide mental system model, and understanding of climate change is to adapt these areas. To carry out this study to develop a theoretical framework for the model to adapt to climate change was discussed in Helmand. The field study was to assess the views of people on climate change action. The review found out that most farmers in this region are aware that the continent is getting warmer, and precipitation or rainfall patterns have changed. People with new changes and features adaptive approach to the challenges ahead were investigated. This data is based on knowledge (awareness) of water and climate change adaptation and mitigation strategies and be ready. So how compliance action is preventive in nature and to reduce the repercussions of climate change and the potential benefits of a region in the face of these side effects are formed. Most respondents aged over twenty years are at least a decade to climate change are felt to be most frequent subjects 30 to 40 years old. The data collected were processed using statistical techniques and modeling for ranking and evaluation of adaptation strategies were created and ASI index. The results for the insights, policy makers and service providers for local development is important, and can be targeted measures used and the promotion and adoption of coping mechanisms with the potential to build resilience and adapt to climate change and the resulting effects environmental prepare.

The results showed that most people in the region following the election of climate change is adaptive behavior. In total, there are 15 strategies in the region. The ASI index rating of strategies to change the pattern of cultivation, selection of resistant strains, reducing the amount of land-cultivated variety is the pattern of adaptation to environmental changes. Ensuring awareness of and adaptation to climate variability call was conducted with the cooperation of the people. Therefore, variability of climate and natural features of the area was measured by various options. The results show that already sampled respondents in the community are aware of climate change. 60% of respondents strongly observed signs of climate change and the dry season and low rainfall and warmer temperatures to believe. The main adjustment options adopted by farmers to temperature in the region include change of product types and number of ships that 61.6 percent of the farmers that their efforts. Another priority is that 39 percent of them tend to change sowing dates and planting varieties resistant to drought. The main recommendations for adapting to new circumstances in this region to stimulate the economy and livelihood of local people can be to diversify crop production (food for example, and cash crops, annual and permanent crops greenhouse) and the use of foreign income from farm sources (ecotourism, rural tourism) can be cited.

Bohlole Alijani, Meysam Toulabi Nejad, Fariba Sayadi,
Volume 4, Issue 3 (9-2017)

Urban climate is strongly influenced by the processes of urban work and life. Expansion of cities and consequently increased human constructions causes to changes in urban climate. The rising temperature of cities rather than the surroundings is one of the effects linked to direct human intervention.
Building heating, air pollution and the use of inappropriate materials in the flooring streets (like asphalt streets due to dark colors in energy-absorption) are effective in phenomenon of urban heat islands that makes unfavorable environment for citizens. Paying attention to the urban surfaces like sidewalk, streets and rooftops has a great role in decreasing effect of this phenomenon. Due to growing urbanization and subsequently cities development, urban heat islands have taken a growing trend in big cities.
In general, the urban heat-island is a result of urbanity features, air pollution, human warmth, presence of impervious surfaces in the city, thermal properties of materials and geometry of urban areas. Heat island phenomenon is a result of many factors that are summarized below: (1) urban Geometry (morphometry) (2) thermal properties of materials which increase the sensible heat storage in the urban texture (3) released human heat as a result of fuel combustion and animal metabolism (4) urban greenhouse gases, leading to an increase in long wave radiation, atmospheric contamination and therefore warmer atmosphere (5) reduction of evaporation levels in cities, which means that energy will be released more as tangible rather than latent heat (6) reduction of turbulence and heat transfer through the streets.
This study aimed to simulate and calculate the maximum amount of heat island (UHI max) according to the conditions of urban geometry in the   region of Kucheh bagh in Tabriz that is a pioneer study in Iran.
The study area is located in Kuche bagh region at the intersection of the streets of Ghods and Farvardin in the city of Tabriz.
The Oke’s numerical-theoretical equation was used for this study. First, the geometry of the target area using the radius of 15 meters from the axis of the road was divided into separate blocks. The ratio of street width (W) and height of buildings (H) was calculated in GIS software and at the end, the intensity of UHImax was calculated and simulated using Oke equation.
The urban geometry including building height and street width is calculated using Equation 1.
The theoretical- numerical basis of this equation shows that simulation of H/W ratio is an appropriate ways to describe urban geometry. Increasing the value of this ratio could lead to an increase in urban heat-island through modeling. This model has many advantages compared to other methods used to estimate the urban heat island. So, the selected parameter to calculate urban geometry and the model used to estimate the maximum intensity of heat island is the ratio of H / W and OKE model, respectively. In addition, the average height of buildings located within a radius of 15 meters and an average width of passages were calculated from the equation 2 and 3, respectively.
After calculating the geometry of the study area, the results showed that the blocks E, G and D in terms of height of the buildings have a heterogeneous distribution, but the distribution of blocks C, I and J is illustrative of their standard configuration. Although the blocks E, F and J in terms of street width are less diverse compared to other blocks, but in terms of height of buildings (8.6, 7 and 5 meters) have a different pattern that  maximum values of  their UHI are 8.3, 7.5 and 6.3 degrees, respectively. Three blocks B, H and I, in addition to their similarity according to street width and height of the buildings, in terms of the ratio of H / W and heat island intensity with the values of 9.6, 9.8 and 10.2 degrees are homogeneous.
It was also found that the greatest difference between the H / W ratio is related to block A (0.54) and block H (1.98); this difference has caused that greatest difference between the maximum intensity of UHI would calculated between the two blocks equal to 5.2 degree.
Misconfiguration causes that energy leaving from city surface deal with the problem due to narrow passages and high buildings. Therefore, consideration appropriate width of passages  and streets and height of buildings are necessary to ease heat leaving and reduce intensity of UHI.
These simulations showed that high buildings and narrow streets intensify the heat islands. While in the presence of short buildings and wide streets, the UHI max is lowered. When the ratio H / W in the studied urban area is between 0.54 to 0.81, UHI max remains between 5 to 6.6 C˚, when this ratio increases to 1.01 to 1.98, UHI max will be between 7.5 and 10.2 C˚. The result also revealed that block A and H with 5 and 10.2 C˚ have the minimum and maximum value of UHI intensity, respectively. So can be concluded that block A and H have the most standard and non-standard urban configuration in the region. The estimates from regression model showed that the street width (91.6%) is more effective than the height of the buildings (6.6%) in changing UHI max.


Fardin Saberi Louyeh, Bohlol Alijani, Shahriar Khaledi,
Volume 6, Issue 1 (5-2019)

. Caspian Sea south coast future climate change estimations through regional climate model
many physical of the procedures related to climate change are not perceived thoroughly. Scientific knowledge used to show those procedures completely, and to analyses forecasts is so complex, since most current studies about climate physical model have been done through semi experimental and random models and most of the current analysis techniques are still going through early stages. One of the important aspects of this study is modeling physical procedures of sea level rise geographical pattern, which is used practically for SLR threat evaluation of special geographical location, meaning Caspian basin. Since Caspian basin is a closed sea, it is heavily influenced by climate change and meanwhile is changing due to physical level and environmental change. It is necessary to define Caspian coast climate change possibility with specific focus on climatology and meteorology fine data, also to define the scale of sea level fluctuations for the sake of exact planning in different fields. This study aims at presenting a new dynamic method, via using an integrated model system named SIMCLIM, which can clarify SLR satellite changes well.
According to scientific examination existing in this study, based on scatter scenario 4.5 RCP and 8.5 RCP for the following years, until 2100, temperature and precipitation change proposal have been presented. On one hand, Caspian coastal climate change analysis and estimation were based on climate patterns and water flows in the form of regional climate statistical model in order to simulate and forecast, on the other hand surveying chronological changes of Caspian sea coast slope with satellite height measurement was done to measure sea surface height fluctuations The present study has used SIMCLIM model for the first time in order to clarify Caspian sea level changes, elements, and effective climate reasons, all simultaneously in one project. The project base is according to coastal systems and procedures. Coast line shore change simulations are based in Bruun law.
In future the frequency and intensity of extreme events temperature and precipitation will increase. Extreme events illustrate changes in extreme temperature and precipitation measures, in comparison with the base period of 1981-2010 which convey precipitation sum or the temperature beyond 95 percentile of base period. Temperature and precipitation coefficient of variation for the whole Caspian basin is positive and it varies from 25 to 88 percent. A disordered pattern is dominating south basin of the sea. Sea level changes, considering vertical earth movements, which is 2 mm in a year, resulted from subsidence of Caspian pit seabed have been obtained for both scenarios. In general, annual sea level average while ignoring seasonal changes, is increasing consistently and it was calculated 1.22 cm each year according to high estimation procedure in scenario 8.5 RCP and it was 0.93 cm based on scenario 4.5 RCP. Predicted results were compared with real results of base20-year period from 1995-2015. Base period results in three levels of sensitivity of low, mid, high shows 8.4, 10.1, and 11.8 cm rise; after comparing them with model forecast results, meaningful coordination at the level of 95 percent was found out. In both scenarios, all over the Caspian shoreline water advance and destruction will exist. In the worst case scenario of 8.5 RCP of 2030, current coast will decrease about 23 meters and in 2060 it will be about 53 and in 2100, there will be 117 meters advance towards land.
Precipitation and temperature percent for 2030, 2060, 2100 will change increasingly. Spatial variability and annul coefficient of variation are various in different regions. North, western north, eastern north and east will include the least temperature fluctuations, and the highest percent of precipitation with the highest coefficient of variation all convey chronological period precipitation distribution with disordered accumulation and more local difference in this region in comparison with other regions. Then Caucasus mountainous region will have the highest increase in precipitation with a suitable scatteredness, during a year. The southern part of Caspian Sea will be with the highest increase in temperature and the least amount of increase in precipitation in percent. High coefficient of variation in this area illustrates abnormal and disordered pattern on the threshold of precipitation for both scenarios.
 fluctuations in sea level based on subsidence of Caspian pit seabed was calculated.In general, average annual sea level is increasing which will be 1.22 cm, per year for scenario RCP 8.5 and 0.93 cm for scenario 4.5. Due to incapability of world community in decreasing releasing greenhouse gases, it is expected scenario that 8.5 RCP to come to reality.
 Caspian Sea shoreline is influenced by water advance and destruction. The difference between two scenarios in 2060 will be 3 meters and in 2100 will be 12 meters. Instinctually, such advances in coasts with less depth and less slope will be more. This study suggests that coastal changes are inevitable. However, this region inhabitant owns no systems or no systems have not yet developed to aid them be able to adopt with the climate changes.
Keywords: Sea level rise, South Caspian basin, Extreme event, Coefficient of variations, shoreline.
Ahmad Porahmad, Hossein Hataminezhad, Keramatollah Ziyari, Seaideh Alijani,
Volume 6, Issue 2 (9-2019)

A new Approach to Urban livability, Thermal Comfort as the Primitive Condition to enhance the livability: Case study, District 22 of Tehran.
Ahmad Porahmad: Professor of Urban Geography and Planning, University of Tehran
Hossain Hataminezhad: Professor of Urban Geography and Planning, University of Tehran
keramatollah Ziyari: Professor of Urban Geography and Planning, University of Tehran
Saeideh Alijani*: PhD candidate of Urban Geography and Planning, University of Tehran
The concept of urban livability is defined as the quality of life and wellbeing of urban residents. That is the interaction of people, environment and built environment. The residents can achieve happy life and well-being only when the nature surrounding them is happy and healthy. According to the range of welfare concept there is a spectrum of quantitative indicators that directly measure (human body temperature, heart rate, air temperature, wind speed ...) and qualitative indicators such as quality of life, pleasure and joy. The comfort and ease of environment are in the middle of the spectrum, in other words, the intrinsic concept of ambient comfort is environment. The inadequacy of natural environment will affect both indicators in the spectrum and lead to citizens' dissatisfaction and decline in social welfare and threaten the health of humans. Living in a salty marsh or very dry hot climate is never happy and satisfied. Accordingly, many concepts such as living quality, living environment, and quality of place, quality of life and sustainability are often used interchangeably with livability).
         This research is trying to weight the natural environment at least equal to the other two components of the sustainable development triangle. Among the components of natural environment, climate is playing the most important and significant role. Urban climate affects all aspects of city including building interiors, city architecture and open spaces. Thermal comfort of open spaces promote the social life and interrelations of residents. Therefore, in order to promote the social relations and economic activities especial consideration should be paid to open spaces. Accordingly, two types of data were measured for calculating the thermal comfort in the district 22. Subjective and objective evaluations which present qualitative and quantitative data. Objective data includes micrometeorological measurements with mobile instruments. Subjective data evaluated actual sensation vote or perception vote of thermal comfort by people using the urban open spaces. To this goal, questionnaires were prepared and scattered through space users simultaneously with micrometeorological measurements. Subjective data evaluated perceptual sensation vote of thermal comfort by people using the urban open spaces in three hot days of August 2018. Nine points are selected for site measuring and field survey which are representative of two types of urban open spaces in this research:1) Urban park and 2) street. Four cardinal points were chosen adjacent to the Shohadaye Khalije Fars Lake inside the park located in sidewalk pathway around the Lake.  Other five points were selected in streets with different orientation and aspect ratio through the district. The physiologically equivalent temperature (PET), mean radiant temperature (Tmrt), sky view factor (SVF) and aspect ratio (H/W) are the most important indicators in this research which were calculated for evaluating comfort in the district.
      Results showed that urban open spaces in the district are discomfort and expose people to the extreme heat stress; over 40°C. This determines that, the natural environment especially around the Shohadaye Khalije Fars is not comfort. The questionnaire also indicated that people felt warm and dissatisfied.
        There is a high linear correlation between thermal comfort and mean radiant temperature and globe temperature. Therefore, it is concluded that thermal comfort in the district, is directly affected by urban areas.  Also in the streets with low SVF and high aspect ratio, PET were calculated more comfortable than other streets. Point 5 at Naghibzade street, confirmed the effect of urban geometry on thermal comfort. Otherwise, the lack of tremendous trees for creating shade is visible especially around the lake. The high linear correlation between Tmrt and SVF around the lake confirmed the openness of the area and the high amount of solar radiation. Therefore, planting more trees for creating the shade effect is necessary. 
        The perceptual analysis of thermal comfort indicated that by increasing of PET, people felt warmer. However, in a city like Tehran, people are more resistance to the heat stress. In addition, the characteristics of human body strongly depends on psychology and individual features and is a hard issue to predict. Otherwise, the people who felt warm were more than those felt slightly warm which indicates dissatisfaction of people. To be noticed that, thermal comfort of above 40 °C in summer is an alarm to urban planner and designers to rethink about climate consideration and global warming as a most important urban challenge in the district seriously. Besides, the consideration of thermal comfort and urban geometry should be imbedded into the comprehensive plan. This research proved that the climatic consideration for improving the quality of life and livability is important and urban designers and planners should rethink and review the comprehensive plan of Tehran to make a livable and sustainable city in the future.
Keywords: urban livability, climate comfort, sustainable development, urban sustainability, urban geometry, physiologically equivalent temperature, district 22 of Tehran.
Nima Sohrabnia, Dr Bohlol Alijani, Dr Mehry Akbari,
Volume 7, Issue 2 (8-2020)

Modeling the discharge of rivers in selected watersheds of Guilan province during climate change
   In this essay, we investigated the effects of climate change on the rivers of selected basins of Guilan province, one of the northern provinces of Iran for the period 2020 to 2050 under three climate scenarios: RCP2.6, RCP4.5, RCP8.5. For this purpose, rainfall and temperature data from 45 climate data stations and 20 hydrometric stations from 1983 to 2013 were used. The average precipitation and temperature at basin level were calculated by drawing both Isohyet and Isothermal lines by usage Kriging method. Mann-Kendall and Sen’s slope estimator tests were used to determine the significance of the data trends and their slope, respectively. The results showed that temperature has increased in all catchments during the study period and this trend was significant in most of them but no significant trend was observed for precipitation. Discharge has also decreased in most basins and this trend was significant in Shafarood, Navrood and Chafrood basins. However, for future periods, precipitation is not significant in any of the climate scenarios, but the temperature is increasing in all scenarios except for the RCP2.6 scenario. Rivers discharge in the RCP2.6 scenario is not significant in any of the basins, but in the RCP4.5 scenario the Shafarood and Ghasht-Roodkan catchments have a significant reduction in the 95% confidence level. In the RCP8.5 scenario, the Chafrood and Shafarood basins have a 99% confidence reduction trend.
Population and technology growth, increased water consumption and climate change have led many researchers to study and model water resources in the present and future periods. Especially in areas like Iran that are facing a lot of water stresses. The purpose of the present study, which was carried out in the Guilan province, is to provide information on the present and future status of surface water resources, and to prepare them for facing the problems of potential water resources exploitation.
In this study 45 synoptic, evaporative and rain gauge stations and 20 hydrometric stations data with sufficient statistics were used. The period of study is also between 1983 and 2013. In this regard, after calculating the average precipitation and temperature values of each basin using Kriging model, first, the annual average of precipitation and temperature values ​​of each basin were calculated. Then, multivariate regression was used to obtain the regression equations between precipitation, temperature and discharge data, then by using SDSM model and climate scenarios (RCP2.6, RCP4.5, RCP8.5) future temperature and precipitation data were generated. By placing these generated data in the Created regression equations, the discharge of the rivers was calculated for the period 2020 to 2050. The trend of time series and their slope were analyzed respectively by Mann-Kendall and Sense tests.
   The study of the annual average precipitation trend of the selected catchments during the study period showed that all the basins had no significant trend at any of the confidence levels (95% and 99%). However, for the temperature there is an increasing trend. In Chafrood, Zilaki, Chalvand, Lavandevil, Tutkabon, Chubar, Lamir, Hawigh, Dissam, Shirabad, Ponel, Samoosh, and Polrood basins there is significant trend at 95% confidence level. For the Hawigh River basin there is significant trend at 99% confidence level. Also in most of the basins there is a downward trend of rivers discharge. In addition, in the three basins of Chafrood, Navrood and Shafarood, there is a significant decreasing trend at 95% confidence level, which is also significant at 99% confidence level for Navrood and Shafarood rivers.
Analysis of future data showed that precipitation is not significant in any of the climate scenarios, but the temperature is increasing in all scenarios except for the RCP2.6 scenario in RCP2.6 scenario. For rivers discharge there was no significant trend in any of the basins, but in RCP4.5 scenario there is a significant decrease in 95% confidence level in Shafarood and Ghasht-Roodkan. Also in the RCP8.5 scenario, a significant decreasing trend of flow discharge at 99% confidence level is observed for Chafrood and Shafarood basins. Finally, the catchments were grouped according to the level of risk involved with decreasing discharge. The results of grouping showed that most of the basins in the three scenarios were in the medium risk group but Shafarood, Chafrood and Ghasht-roodkhan watersheds have higher risk than the other watersheds, respectively.
Investigation of river discharge trends for the period 2020 to 2050 in different scenarios showed that the basins of Ghasht-roodkhan, Chafrood and Shafarood are more sensitive to climate change than other basins. Overall, escalating temperature trends in future and precipitation irregularities can create very difficult conditions in future to use these resources. Especially, this study's concordance with other studies in Iran and the study area confirms that such crises are more likely to occur..
Keywords: Climate Change Scenarios, Rivers Discharge, Man-Kendall, Sen’s Slope estimator, Guilan Province

Bohloul Alijani,
Volume 7, Issue 4 (2-2021)

Corona Virus pandemic outbreak is the counter act and warning of the natural environment for the destructive activities of man in the nature. Many researchers and specialists believe that  a risk free and sustainable life is possible if we correct our behavior toward the nature. This research was carried out to substantiate this hypothesis and offer a reasonable and rationale solution. It is believed that the best way to solve this problem is the environmental ethics. Many other ways such as technology have been proposed, but until the mind and thought of man has not changed to good relation with the nature, it is not possible to reach a viable solution. For this end, the integrated system of earth was analyzed to understand mechanism of the relation between nature and human. Two supportive theories of Markov Blanket and Gaia were addressed here to explain the relation between nature and society. According to these theories the system of earth and society is live and any change in one will mirror itself on the other. As a result, the society models itself to the nature in long run. This means that to have a healthy society we should have a healthy nature and environment. Thus, the UNEP has suggested the integrated One Health program to save nature, humans and animals at the same time.
       The distortions of the earth during the past 70 years were sampled and described as the footprints of mankind. Some examples of environmental disorders such as climate change, droughts, floods and diseases were analyzed and their impacts on the society were displayd.   In order to demonstrate the environmental ethics as the only solution to the current crises, first the ethics in general were discussed and then the environmental ethics were given a thorough explanation. Different underpinning philosophies are presented and accordingly different approaches to the nature such as development, preservation and conservation were discussed. A new philosophy, geocentrism, was suggested as the suitable and efficient thought. According to this philosophy it is the distributions which are in the forefront of human destruction. Therefore, we should try not to disturb the distributions of any kind. These include all ecosystems of any scale; because emphasizing on the ecosystems is not sufficient. The geocentrism philosophy covers all non - anthropocentrism philosophies such as biocentrism and ecocentrism. Of the different approaches, the conservation was selected as it assumes intrinsic value for the nature and sustainability of resources for ever. 
        To solve the problem and bring the earth system to sustainable state, the environmental ethics should be implemented. In terms of moral values, these include truth, good, duty and justice. The mankind should characterize himself with these genuine characters. He should do his duty as not making problem to the life of any creature; this being human, plant, animal or rock and soil and etc. He should do the good and justice. On the objective side, he should give intrinsic value for every creature on the earth including the environment and its components. In this way, we treat the environment with respect and dignity and not let ourselves to destroy or damage it. However, to achieve these goals we should use resources only as much as we need biologically, consider the long run benefits instead of short term benefits, treat the nature as having intrinsic value, implement the environmental distance from wild life, using vegetarian diet.
      One important notice is the nature of human who we are asking to do these mandatories. Are we sure that what we are ordering human will be done by him. If he does not do then none of these comments is valuable. Therefore, we first should understand the humans and educate them to accept our orders. This is why that the ethics become important. We should train moral humans and then ask them to do. He will do only when he gets overarching and believed knowledge   about the subjects we are offering. The main reason for the distortion of the nature is that the humans are not aware of the value of nature and the long run results of their actions. This is possible only through the good and responsible training of man. We are now missing this education. In brief, we understand that the main solution for the destruction of nature is empowering the humans with morals, especially environmental ethics. But to implement this objective, at the first point we need a wise and understandable human. Therefore, first we should train people and ask them to act as a moral and generous person and care for the nature and all creatures of the universe.
Key words: Corona Virus, Covid-19, sustainability, environmental ethics, human-nature relation, Markov Blanket, natural resources, UNEP One Health program, Gaia, Anthroposcene.
Professor Bohloul Alijani,
Volume 8, Issue 3 (12-2021)

Geography and the Paradigm of Sustainable Development
Extended Abstract
Geography and sustainable development
The relation between society and environment has gone through different phases. During the years before the World War II, the environmental determinism controlled this relation. However, after the 1950’s the anthropocentrism replaced the environmental determinism and humans began to overuse the nature in such a way that nature lost its sustainability and many hazards and crises occurred. These destructions were so intense and widespread that some researchers compared with the episodes of geologic time and named the era beginning from 1970’s the Anthropocene epoch. During this period, the planetary boundaries were crossed in some areas such climate change, nitrogen cycle and biodiversity. Climate change has created most of other hazards.
To overcome these problems in 1978 the Brandtland report   announced the sustainable development as not to spend resources more than the nature’s production capacity and not to pollute the nature more than it can assimilate. In other words, the nature should remain in its sustainable state so that the future generations can live with no limitations. The principles of the sustainable development were defined in the earth summit of Rio in 1992 such as social equity, economic viability, and environmental sustainability. These principles were broken down in 17 goals. The Rio conference asked all countries to achieve the sustainable development goals by 2030. 
Methodologically the sustainable development requires integrated multidisciplinary approach to investigate the complex system of human- environment in different temporal and spatial scales to achieve the social equity, economic viability, and environmental sustainability. For this reason, many disciplines such as natural resources, environmental sciences, ecology and geography have contributed to the field. Different data from natural resources, human needs and drivers and environmental changes are required to process in very complicated models. In addition to different variables, the hazards are very important component of the sustainable development research, which also requires multi-aspect complicated approach and models. Spatial dependency is another aspect of sustainable development as it differs from place to place in many characteristics. In brief, from the spatial perspective the sustainable development is an integrated multi-approach research about the human-environment system to establish the sustainability on the earth. All of the related fields should study the sustainable development in collaboration with each other. However, the geography due to its long history of studying the relation between human and environment and its spatial dependency is the best single scientific field which can afford studying the sustainable development. Since the earliest times geography has developed quantitative methods, spatial techniques such as geostatistics, and environmental ethics to conserve the nature and human prosperity. The multi approach and systematic works are the main characteristics of Geography. On the other hand, Geography’s vision of defining the location for human’s activities while saving the nature’s sustainability covers the sustainable development completely. Therefore, geography is the overarching field for the sustainable development and it is the main intention of geographers to research and implement the sustainable development to reduce the environmental hazards and develop the sustainable environment for all the human beings at present and in the future. Geography studies the sustainable development through three steps including spatial analysis, spatial planning, and spatial management. In addition, geographers should learn different skills such remote sensing, multivariate statistics and above all develop a common language between different branches of geography.
Keywords: geography, sustainable development, environmental ethics, human nature relationship, Anthropocene, planetary boundaries, sustainability.
Mrs Fatemeh Falahati, Dr Bohlol Alijani, Dr Mohammad Saligheh,
Volume 8, Issue 4 (1-2021)

In many areas, snow cover in the mountains is a major source of surface and underground water supply. Due to climate change and its effect on the time of melting ,it  is very important for environmental planning to predict the arrival time of water from snow melt to water consumption cycle. The purpose of this study is to investigate the volumetric changes and time distribution of snow flood flows in future by integrating remote sensing , GIS and climatic models.The studied area is the Upper Basin of Amir Kabir Dam, which is located on the southern slopes of Alborz Mountains. In this study, digital elevation maps (DEM) and GIS software were used to estimate parameters such as area, environment, main length, highest and lowest elevation points. In order to complete the snow cover data, MODIS products (MOD10A100) were extracted and the snow cover was extracted in the Upper Basin of Amir Kabir Dam. Next, runoff and snow melting models were simulated using SRM software. Calibration and validation of the model's acceptable performance were estimated. Then, in order to investigate the effects of climate change on the future of snowmelt runoff production in the basin of Amir Kabir Dam, the latest CMIP5 climatic models were used under four scenarios RCP2.6, RCP4.5, RCP6.0 and RCP8.5. A survey on the relationship between snow cover area , temperature and precipitation was used to predict snow cover in the future. The increase in temperature in the autumn and winter season has led to a reduction in the shape of precipitation in the form of snow, and as a result, the amount of snow storm is reduced. The results show that the amount of runoff in the autumn and winter increases due to increased rainfall in the form of rain, and it will be  increased late winter and spring due to the increase in the amount of water resulting from snow melting. The results of this study are based on the increase of snow melt as a result of increased runoff volume, reduction of snow reserves and maximum flow transmission to earlier than normal conditions due to early snow melting due to temperature rise. Generally, in the future, the average annual runoff will be decreased about 1.1 cubic meters per second, and the average annual melting share will be about 13.9%
- Mahmoud Roshani, - Mohammad Saligheh, - Bohlol Alijani, - Zahra Begum Hejazizadeh,
Volume 8, Issue 4 (1-2021)

In this study, the synoptic patterns of the warm period of the year that lead to the cessation of rainfall and the creation of short to long dry spells were identified and analyzed. For this purpose, the rainfall data of 8 synoptic stations were used to identify the dry spells of the warm season for 30 years (1986 to 2015). The average daily rainfall of each station was used as the threshold value to distinguish between wet and dry spells. Then, according to the effects of dry spells, they were defined subjectively and objectively with different durations. Thus, 5 numerical periods of 12 to 15, 15 to 30, 30 to 45, 45 to 60 and more than 60 days were identified. By factor analysis of Geopotential height data at 500 hPa, 4 components were identified for each period and a total of 20 components for 5 dry spells. Therefore, 5 common patterns control the stable weather conditions of dry spells. Most dry days are caused by subtropical high-pressure nuclei, which have a wide, even, dual-core, triple-core arrangement. The effect of subtropical high pressure on the dryness of the southern coast of the Caspian Sea is quite evident. Other dry days were caused by southerly currents, weakening of northern currents, and the trough Anticyclones’ area. Also, the anomaly map of the components days at the 500 hPa level showed that the anticyclones and cyclones correspond to the positive and negative phases of the anomalies, respectively.

Ms Mahsa Sepasian, Dr. Bohloul Alijani, Dr. Mohammad Salighe, Dr. Mehry Akbary,
Volume 8, Issue 4 (1-2021)

Tehran metropolitan with its large population, daily migrant workforce and many students, needs to planning and designing watch/warning system to reduce the climatic problems for human health.for this purpose, we need to study the climate accurately and Since the factors affecting the climate of warm and cold periods in Iran are different, in this study , the meteorological variables of Tehran warm period (May to September 2002) turned into 4 components in Temporal Synoptic Index (TSI) using PCA Method and using P-Array and Varimax rotation.By the scores of components for each day, the clustering method (in ward method) were used and, the warm days of the year was divided into two cluster named favorable and oppressive airmasses. The average maximum air temperature that is more effective in mortality, was 36.13 ° C. Days with temperatures above  34 ° C, less pressure, mild winds , dryness and more sunshine resulted in more adverse weather conditions, which resulted in a 34% increasing in mortality compare with favorable weather. The total number of deaths from cardiovascular disease during the study period was 154046 that about  67%of deaths have been simultaneous with oppressive airmass.The epidemiological study of mortality also confirms the results of previous research in this area and shows that the incidence of mortality is higher in older people as well as in men. It is clear that not all mortality can be attributed to the effects of climate, but results show that change in climatic conditions will affect on mortality and also for study the effect of climatic hazards on human health, it is better that we study the effect of all variables together on humans.

Fatemeh Arsalani, Bohloul Alijani, Sabereh Arsalani,
Volume 8, Issue 4 (1-2021)

Dust fall means the dust that in the air fall down on the ground (Hai et al, 2008). it is important to study the extent of heavy metal contamination of dust fall due to their threats that could affect human health. Due to the fact that the metropolis of Tehran has a population of over eight million people and One of the major cities in the world is currently facing a severe air pollution problem. The purpose of the present study was to determine  the level of pollution and health risk of heavy metals such as Cd, Cr, Cu, Ni, Pb in the dust falling of Tehran city. the Dust fallout samples were collected using Marble Dust Collector (MDCO) from 28 different locations across Tehran during the statistical period (2018/03/21- 2018/06/21). We used XRF analysis To identify and determine the concentration of heavy metals (Cd,Cr,Cu,Ni,Pb,Fe) in the collected dust. we used to spatial analysis to  determine Dispersion of pollution levels and health risk in different Zone of Tehran  city. In order to determine the level of pollution and Health Risk Assessment we used the pollution index (PI), integrated pollution index (IPI), Non-Carcinogenic Risk and Carcinogenic Risk. Based on the results of the calculations performed in the statistical period studied, the values of pollution index (PI) and integrated pollution index (IPI) are Pb> Cd> Cu> Cr> Ni, respectively. Accordingly, the regional trend of pollution from west to east is increasing. Therefore, Tehran's pollution index is high level of pollution in the most zone and and extremely high level of pollution in the eastern zone, which is a more worrying situation. Probably one of the reasons is the western winds, which are faster in the west than in the east. Also, Tehran's topographic pattern plays a role in this issue. Health risk assessment (HQ, HI, CR) showed that the contamination of the heavy elements studied was lower than the acceptable threshold for carcinogenic and non-carcinogenic risks. Therefore, it is not dangerous in terms of carcinogenicity. The risk of carcinogenicity and non-carcinogenicity in children and adults is higher in the southern and eastern zone of Tehran. Probably one of the reasons is the establishment of metal industries, cement production, sand mines and combustion processes in the south and west of Tehran metropolis.
Ms Vahideh Sayad, Doctor Bohloul Alijani, Doctor Zahra Hejazizadeh,
Volume 8, Issue 4 (1-2021)

Iran is a country with low rainfall and high-intensity rainfall that is affected by various synoptic systems, the most important of these systems is Sudan low pressure, Therefore, recognizing the low pressures of the Sudan region is of particular importance, The purpose of this study is to gather a complete and comprehensive knowledge of the set of studies conducted about this low pressure, structure and formation and its effects on the surrounding climate. The present study was conducted using the library method and a search for authoritative scientific and research sources in connection with research on low pressure in Sudan and no data processing was performed in it. Thus, it has studied and analyzed the temporal and spatial changes of Sudan's low pressure over several years and its effect on the climate of the surrounding areas, especially Iran. In general, the results of this study can be divided into several categories, including studies on the recognition and study of Sudan low pressure, its structure and formation over time, pressure patterns affecting it at different atmospheric levels, and its effects on the climate of surrounding areas, especially Iran. Has been studied, The effect of this low pressure on seasonal and spring rainfall in Iran, snow and hail, floods, thunderstorms and also the effect of remote connection patterns on this low-pressure system have been studied, and finally, the analysis of these findings has been studied. It can be concluded that the Sudanese low-pressure system is a Low-pressure reverse in the region of Northeast Africa and southwest of the Middle East, which is strengthened and displaced in the upper levels of the Mediterranean and Subtropical jet stream and in the lower surface moisture injection from the Arabian Sea and Oman through high pressure. Saudi Arabia is inwardly the cause of severe instability in Iran and a major cause of heavy rainfall in various parts of the country.
Mrs Masoumeh Alidadi, Professor Bohlol Alijani, Dr Mohammadhossein Nasserzadeh, Professor Zahra Hejazizadeh,
Volume 9, Issue 1 (5-2022)

Comparative analysis of snowfall events in Iran with emphasis on the location of the polar plateau and remote connection patterns

Extream snowfall event that may occur at any time during the cold season, has significant social and economic implications. Therefore, the economic and social consequences of these events reveal the importance of identifying the synoptical mechanisms associated with the extream snowfall events. In order to achieve this goal, using daily precipitation and temperature data during the statistical period of 1951-1 2016 and based on multiple criteria, the two three-days extream snowfall events were identified during February 7-9, 1972 and February 2-4, 1988. After selecting samples, a statistical analysis of the teleconnection indices was done and then, using the NCEP-NCAR reanalysis data, the combined patterns of surface and lower, middle and lower troposphere were plotted in the form of three-days mean. Results obtained from analysis of teleconnection indices and their correspondence to the synoptic patterns indicate the weakening of the tropospheric polar vortex and its division into multi-centers in the periods of extream snowfall events. In the event of February 7-9, 1972, though the centers were moved to mid-latitudes, but they are not completely out of the Arctic and to some extent maintain their position in this area. In February 2-4, 1988, the vortex centers have shown a more equatorwards displacement towards the mid-latitudes that the emergence of negative phases of the NAM and AO represent such a situation. However, in both events, the strong and main center of the polar vortex is located in the eastern hemisphere and therefore in a state close to Iran. The weakening of the sub-tropical jetstream in the eastern hemisphere, especially in the Mediterranean, has resulted in the transmission of potential vorticity tabs to mid-latitudes. The equatorwards progress of these tabs has led to the formation of the trough in the western and eastern Mediterranean regions that accompany with a ridge between them, led to the formation of omega bundle patterns and split flow, respectively, in the events of February 1972 and 1988 in this geographical area. The southern boundary of the progress of the troughs has specified by index contour of the edge of the vortex by 552 gpdam, that extends to the southern part of Iran and in the February 1972, event compared with the pattern of the February 1988, had the more-equatorwards progress toward the middle latitudes, and as a result, over Iran.
Keywords: extream snowfall event, teleconnection, polar vortex, the edge of the vortex, blocking patterns.


Rasool Nooriara, Seysd Jamalaldin Daryabari, Bohlol Alijani, Reza Borna,
Volume 9, Issue 3 (12-2022)

Synoptic analysis of the torrential on Day 21, 1398 (Case study: Zahedan and Qeshm)

Rainfall is the most important phenomenon or feature of the environment and so far many studies have been done about its causes. In any place, rainfall occurs when humid air and climbing cause are provided. Both of these conditions are provided by the circulation pattern. The study area is affected by some severe and sudden weather phenomena such as low annual rainfall, short rainfall period and rainfall in the form of heavy showers. Thus, it is possible that the limited and pervasive precipitation of the area is due to a different synoptic pattern. Because the relationship between circulation patterns and precipitation is significant, achieving acceptable results in the field of the relationship between these patterns with the limit and total rainfall of the studying area requires the analysis of synoptic maps. Therefore, the most important purpose of the present study is the synoptic analysis of heavy cloud rainfall of the studying area on Day 1398.
Two sets of data were required for this study: A: Daily precipitation data of study stations on the day of heavy cloud rainfall on 21 Day (January 11, 2020) along with daily precipitation data in the days before the flood (96 hours before the flood) which was received from the main Meteorological Organization of the country.
B: atmosphere data levels including: sea level (SLP), 850 and 500 hPa levels, vertical atmospheric velocity and wind flow levels of 1000, 850 and 500 hPa, specific humidity of 1000 and 700 hPa levels and 250 hPa surface flow winds for study days from the US National Center for Environmental Forecasting / National Atmospheric Research Center (NCEP/NCAR) were provided in the range of 0 to 60 degrees at north latitude and 0 to 80 degrees at east longitude, and finally, maps were drawn and prepared in Gardes software to provide the ability to interpret.
The synoptic analysis of sea level showed that: on the day of the heavy cloud, a low-height closed center with a central core of 1,010 hPa in the northeast-southwest direction covered the entire study area. Then, the high-height with a central core equal to 1030 hPa is located at northwest of Iran, northwest of Europe and on Tibet. According to the location of high-pressure dams around Iran and the location of low-pressure centers on the study area and water resources in the south, a strong pressure has been created. Subsequently, with height increasing, low-height with central core equal to 1440 geopotential meters is located at northeast-southwest direction of entire study area. And the low height of northern Russia extends to the Persian Gulf and provides the conditions for severe ascent and instability in a very large area. The rear dams of Nave transferred the cold air of the high latitudes into the bottom of the Nave located on the study area and have intensified the instability. Also, the geopotential height of 500 hPa level of deep descent is located at the northeast-southwest direction of Iran and core of the Nave covers the Persian Gulf completely, that is the study area in the best condition and in front of the Nave, which is diverged by hot and humid weather. This deepening of the rotation and the penetration of the Nave to the lower latitudes caused the cold air to fall. 
The analysis of the 250-hectopascal-level flow-wind shows that the flow-wind with a core speed of 65 meters per second has covered the entire study area by crossing above the Persian Gulf, and compared to the previous days, the flow-wind is completely meridional.
Synoptic analysis of the vertical velocity at the level of 1000 hPa shows that the maximum negative omega -0.2 to -0.15 Pascal per second in the northwest-southeast direction has covered the study area. The presence of negative omega index values ​​indicates the role of convection in intensifying precipitation in mentioned area and the dynamic ascent of air. The study map shows that compared to other countries in the study map, the maximum of negative omega is located on Iran, which is reduced along to the west of Iran. With increasing altitude, the maximum negative omega has increased to -0.3 Pascal per second and the core of the maximum negative omega is completely located on the study stations (Zahedan and Qeshm). Then, at the level of 500 hPa, the maximum negative omega has reached -0.6 Pascal per second and its value has doubled compared to the level of 850 hPa, which covers the northeast-southwest direction from Zahedan to the Strait of Hormuz. Cold air fall has increased with increasing of omega levels in the middle levels of the atmosphere.In other words, in the middle levels of the atmosphere, with increasing temperature difference between the earth's surface and the level of 500 hPa, the amount of precipitation has increased.
Synoptic analysis of specific moisture level of 1000 hPa shows that the most moisture deposition was from south water sources to the study area, and the amount of moisture equal to 14 grams per kilogram has entered the study area from the Oman Sea and then its amount has been reduced crossing to other regions of Iran. Furthermore, at the level of 700 hPa, the maximum advection of hot and humid air is in front of the upper atmosphere of Nave from the Red Sea over the study area. There is a moisture strip from the southeast to the whole area under analysis. These suitable humidity conditions with the depth of the western wave have been able to cause heavy cloud rainfall. The maximum amount of moisture in the study area is equal to 7 grams per kilogram, which is a large amount compared to heavy rainfalls.

Keywords: heavy rainfall, flood, synoptic, Zahedan, Qeshm

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