Land use Planning
Hasan Masoudi; Davood Amini; Hamed Ebrahimi
Abstract
Governments and societies have historically divided their territories into different regions and areas to better manage their land and preserve the territorial integrity of their country. This practice is now related to the concept of spatial planning, particularly "Territorial Zoning". Territorial ...
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Governments and societies have historically divided their territories into different regions and areas to better manage their land and preserve the territorial integrity of their country. This practice is now related to the concept of spatial planning, particularly "Territorial Zoning". Territorial Zoning aims to achieve cohesive management and the National Division of Labor, as well as utilize the potential of different regions to reduce territorial inequalities and imbalances. In Iran, Territorial Zoning has been implemented by various organizations over the past decades, with the most recent division into nine major regions in 2017. In this descriptive-analytical research, the extensive literature on Spatial planning and Territorial Zoning plans in Iran is reviewed, providing a comprehensive history of these programs. The research then critiques and analyzes these programs. The most important criteria influencing land zoning are identified and prioritized using the Analytic Hierarchy Process (AHP) method and the opinions of experts. According to the findings, the most important criteria for Territorial Zoning are "cultural-social", "defense-military", and "political-administrative". The sub-criteria of "environmental issues", "level of regional development", "population distribution", "government pattern and type", and "threats and security issues" are also deemed important. Based on the findings and results of the research, the authors propose their own Territorial Zoning plan in the form of ten major regions. This research contributes to the understanding of the history and current state of territorial Zoning in Iran and provides valuable insights for policymakers and practitioners in the field of Territorial Zoning and spatial planning.
Climatology
vahid safarian; Ahmad Fatahi Ardakani
Abstract
The aim of the present study was to estimate Iran's climate change based on the CMIP6 report with the approach of satellite data using climatic elements (minimum temperature, maximum temperature and precipitation) until the year 2100.The tools used in this research included innovative algorithm ...
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The aim of the present study was to estimate Iran's climate change based on the CMIP6 report with the approach of satellite data using climatic elements (minimum temperature, maximum temperature and precipitation) until the year 2100.The tools used in this research included innovative algorithm methods, coding and NASA data. In order to evaluate and predict the climate elements, the moderate scenario (SSP2_4.5) and the very pessimistic scenario (SSP5_8.5) of the Canadian CanESM5 model based on greenhouse gas emissions, which were common socio-economic paths (SSPs), were used. For better analyze, investigate and compare Iran's future climate changes, the studied period of 80 years was divided into the two periods the near future (2021-2060) and the distant future (2061-2100). The results showed that in the first 40-year period (2021-2060), based on the SSP2-4.5 scenario, the change of climatic elements was reported as minimum temperature of 1.91 °C, maximum temperature of 1.41 °C, and maximum amount of precipitation of 15.22 mm for the coming years. Also, for the second 40-year period (2061-2100), based on the SSP2-4.5 scenario, the process of changing climate elements with minimum temperature of 1.71 °C, maximum temperature of 1.17 °C and maximum amount of precipitation of 22.25 mm for the coming years were predicted. According to the findings obtained from CMIP6 and using SSP2_4.5 and SSP5_8.5 scenarios in forecasting climatic elements, the results showed that the amount of minimum and maximum temperature climatic elements was associated with an increasing scale and this increase in SSP5_8.5 scenario was greater than in the SSP2_4.5 scenario. Also, the forecast amount of precipitation based on the SSP2-4.5 scenario in the near future period (2021-2060) will be less than the far future period (2061-2100) and the amount of precipitation in the SSP5-8.5 scenario will decrease compared to the SSP2-4.5 scenario.
Climatology
Hassan Rezaei; Gholamabbas Fallah Ghalhari
Abstract
Understanding the climatic potentials of the regions is very important for the diversity and talent of agricultural products. Barberry, one of the products of Iran, suffers from climate change and anomalies. In the present study, the phonological stages of barberry tree without any basis of field observations ...
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Understanding the climatic potentials of the regions is very important for the diversity and talent of agricultural products. Barberry, one of the products of Iran, suffers from climate change and anomalies. In the present study, the phonological stages of barberry tree without any basis of field observations in Ghaen synoptic meteorological station were determined. To measure the accumulation of cooling needs based on the cold clock model and the Utah unit, the statistics of 18 valid meteorological stations from 1987 to 2017 on an hourly and daily time scale were used. The results showed that barberry needs six phonological stages to complete the growth period from early April to late November. The highest temperature requirement occurs in the ripening stage until fruit development. The cooling requirement of barberry tree in different stations varies from 1050 to 1960 hours depending on climatic conditions. Field observations showed that seedless barberry does not take on a full and commercial color if it does not meet the need for sufficient cooling. The study area was zoned according to the models of the cold clock and the Utah unit, based on which Ghaen and Zahedan stations have the highest cooling needs. Based on the validation indices of different models estimating the need for cooling, the root mean square criterion was used and the results show that the cold hour (CH) model has a higher performance due to the fact that the root mean square (RMSE) is less than the other model.
Climatology
Fatemeh Taghavi nia; Batool Zeinali; Abbasali Dadashi Roudbari
Abstract
Climate change is a key factor in most weather-related disasters worldwide. Regarding its distinctive geographical location and diverse climate, Iran has the most variable climate in the world. The present study aims to investigate the effectiveness of the MPI-ESM-LR model from the CMIP5 model series ...
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Climate change is a key factor in most weather-related disasters worldwide. Regarding its distinctive geographical location and diverse climate, Iran has the most variable climate in the world. The present study aims to investigate the effectiveness of the MPI-ESM-LR model from the CMIP5 model series in predicting the monthly temperature of Iran under representative concentration pathway scenarios (RCPs) with the CORDEX-WAS project. In this research, for the historical period of 1980-2005, the daily air temperature data of 49 synoptic stations of the country and the MPI-ESM-LR model under the CORDEX project were used. Likewise, for the future period, from the predicted temperature data of RCP 8.5, RCP 4.5, and RCP 2.6 scenarios of the mentioned model in three periods of the near-future (2021-2050), mid-future (2051-2075) and far-future (2076-2100) was used. Validation of the model was done with three statistical indices: r, RMSE, and MBE. The results revealed that the model has a good performance. The slope of the temperature trend in station data and model data has been increasing in the historical period and the future period in RCP8.5 and RCP4.5 in all months, the temperature trend slope has been observed in every decade. In all months, the maximum anomaly of temperature under the scenarios studied in all three future periods can be seen in the northwest and western highlands. The eastern and southeastern regions of Iran have indicated minimum temperature anomalies, except in RCP 2.6 and RCP 8.5, respectively, the southern coasts and the northeastern heights of the country also show minimum temperature anomalies. In the cold half of the year, the minimum area of temperature anomaly has been extended to the north-western heights and low-altitude interior regions of the country.
Yousef Zarei; Ali Mohammad Khorshiddoust; Majid Rezaeebanafshe; Hashem Rostamzadeh
Abstract
Climate change is one of the main problems on Earth today, so predicting these changes in the future and their impacts on water resources, the natural environment, agriculture, and environmental, economic and social impacts is of particular importance. Therefore, in the present study, the effects of ...
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Climate change is one of the main problems on Earth today, so predicting these changes in the future and their impacts on water resources, the natural environment, agriculture, and environmental, economic and social impacts is of particular importance. Therefore, in the present study, the effects of global climate change on different climatic regions of the country were studied in 12 climatic regions. In this study, NCEP data and climatic elements of precipitation, maximum and minimum temperature were used for statistical downscaling with SDSM model. And using the CanEMS2 model output under RCP scenarios for the three statistical periods of 2011-2040, 2041-2070, and 2071-2099 annual climate change data were obtained. Correlation coefficient, determination coefficient and error indexes of RMSE, MSE and MAD were used to evaluate the performance of the model. However, the results showed that the accuracy of the model was different at different stations. In this way, each model performs better than rainfall in simulating minimum and maximum temperatures. The annual long-run results also show that precipitation will decrease in all climates studied in the coming decades, with the largest decrease occurring in semi-warm (35%) and very humid and temperate (32%) desert areas. But minimum and maximum temperature variations will be different in different climatic regions so that under RCP scenarios during all statistical periods at Sabzevar and Tabas stations minimum temperature changes will decrease but in other climatic regions the trend of minimum and maximum temperatures will be incremental. The highest minimum and maximum temperature increases based on RCP scenarios under RCP8.5 scenario during the period 2071-2099 in the cold mountain climatic region will be 3.03, 4.27 ° C, respectively.
Climatology
Behrooz Sarisarraf; Hashem Rostamzadeh; Mohamad Darand; Omid Eskandari
Abstract
Precipitation is one of the most important and variable climatic elements that changes in time and place. Critical rainfall at various time scales, especially daily, causes severe damage to human communities in densely populated urban areas and natural ecosystems and affects many arid economies. Earth ...
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Precipitation is one of the most important and variable climatic elements that changes in time and place. Critical rainfall at various time scales, especially daily, causes severe damage to human communities in densely populated urban areas and natural ecosystems and affects many arid economies. Earth outgoing long-wave radiation is studied as a significant parameter to detect clouds and estimate this type of precipitation. The current study aims to examine the relationship and analysis of outgoing long-wave radiation variables and precipitation values in Arc GIS software environment for the four cold months 17 statistical years in Iran using AIRS sensor products of Aqua satellite and GPM satellite. Correlation and regression models and confidence interval estimation were used to measure the correlation of long-wave radiation output in predicting precipitation patterns and their changes. According to the results obtained in all months studied, In the whole country, except Caspian Sea basin in January, parts of the central and eastern plateau of eastern Iran, there is a negative correlation of 10 to 92%, Which indicates that the country's atmosphere is humid and prevents the release of outgoing long-wave radiation. In the western rainfall areas of the Zagros Mountains, negative correlations above 70% and outgoing long-wave radiation is less than 260 W⋅m−2 which is due to cloudy and humid atmosphere with precipitation.In December and February, the rainfall areas north of the Caspian Sea basin range have negative correlations of above 50% and OLR less than 235 W⋅m−2 of rainfall and the reason for the lower numerical value north of the Alborz mountain range to predict is the existence of high relative humidity in the region, which is the cause of less outgoing long-wave radiation output of the earth.
All other Geographic fields of studies , Interdisciplinary
Mostafa Karimi; Sousan Heidari; Morteza sharif
Abstract
IntroductionIncrease temperatures and decrease rainfall can lead to the drying up of wetlands, lakes and rivers, the formation of aerosol centers, which directly and indirectly change the structure of society and the ecological conditions of lakes around the world; As a result, it leads to changes in ...
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IntroductionIncrease temperatures and decrease rainfall can lead to the drying up of wetlands, lakes and rivers, the formation of aerosol centers, which directly and indirectly change the structure of society and the ecological conditions of lakes around the world; As a result, it leads to changes in the distribution of animal and plant species, ecological diversity, changes in the plant phonological cycle, factors, growth and organisms, and ecological metabolism. These changes also severely affect vegetation in arid and semi-arid climates. Finally, changes in surface conditions caused by human activities may also affect various hydrological processes. Thus, the twenty-first century is facing many environmental problems, one of the most important of which is the variability of environmental and climatic parameters. Lake Urmia is one of the most important water areas in Iran and one of the largest salt lakes on earth. The lake plays an important role in the climatic, environmental and economic situation and a national and international natural heritage in the northwest of Iran.variability of environmental and climatic parameters is one of the most important challenges for human specific in arid and semiarid environment such as Iran. The purpose of this study is to investigate the changes in environmental and climatic parameters in the catchment of Lake Urmia in the last two decades. The purpose of the above was to answer the question of how the changes in environmental and climatic parameters in the basin and the relationship between these changes in the current conditions of the basin Lake Urmia.Data and methodsResearch data includes six categories: 1) TOPEX and Jason 1 to 3 satellites data to study of changes in altitude level of Lake Urmia, 2) Landsat 7 satellite images of 2000 and Landsat 8 of 2019 for extract lake water area changes and 3) Precipitation data from GPM[1] satellite product (IMERG[2]) 4) Vegetation index products of Modis sensor (Mod13A3 v006) to identify vegetation changes, 5) LST Night and daytime of Modis sensor (MOD11A2 v006) and finally 6) gridded reanalysis data (ERA5) to detect of trend air temperature, were used.First, the changes in the water level of the lake were extracted using the data of TOPEX and Jason 1 to 3 satellites, and in the next step, the trend of changes in its was calculated. Landsat 7 images of 2000 and Landsat 8 of 2019 using the Normalized Differential Water Index (MNDWI) were used to achieve changes in the lake's water area. Then LST (day and night) of MOD11A2 v006 products were converted into monthly data using MATLAB software. Finally, the trend changes in precipitation data, 2 m air temperature, LST (day and night) and vegetation (NDVI) were investigated using Mann-Kendall test (Mann, 1945; Kendall, 1975).ResultsThe highest changes in water level in the last two decades are from 2000 to 2010. The decrease in level is evident from the year 2000, from that year to 2010, the water level of the lake decreased by 4 meters and the highest slope of the decrease in it observed in the same period. The change in the area obtained from the MNDWI index is 2740 km2, which has caused the lake to decrease from 5143km2 to 2400km2 in 2019. The decrease of the lake level in its southern and eastern part has been more than the western and northern part. The trend of monthly precipitation changes shows two different temporal and spatial patterns. It is important to note that there is a monthly decreasing trend every three months in January, August and December in the central and southern parts of the basin. In contrast, in May and July, a marked increasing trend is observed in the eastern and southern half of the basin. Spatial displacement of incremental changes in air temperature indicates a clockwise movement from north to east and then south and west from May to August. The trend of day of the LST changes indicates a spatial contrast between the Lake and around it. This behavioral contradiction is more pronounced with the increase of the lake surface temperature and the decreasing trend in the southern and western regions corresponding to the agricultural areas in August, September and October. Changes in LST at the basin level from November to February, in which scattered and small incremental zones are observed, can also be due to reduced vegetation in the cold period of the year. In contrast to the daytime LST, at night what is most noticeable is large zones of temperature rise, especially from June to September throughout the basin. NDVI in the period 2019-2000 has had an increasing trend in all months, but with varying intensity and extent. Three temporal patterns are understandable in the process of basin vegetation change. Increased from January to May, then start decreasing trend from June to August and again increasing trend that continued until December. The lowest increasing trend is observed during the summer months from June to August.DiscussionLake Urmia has experienced a continuous decrease in water level since 2000, so that during the last twenty years, the water level has decreased by more than seven meters. The results of the present study also showed that there was a significant increasing trend in the NDVI index at the basin, especially with the southern of the basin. However, at the basin level, the trend of rainfall changes in this period (2000-2000) is not generally significant and also due to the occurrence of numerous droughts in the basin, which has also had an increasing trend and the expansion of irrigated lands, Demand for groundwater has increased. Therefore, this issue indicates various reasons other than changes in climatic parameters, especially precipitation in reducing the water level of Lake Urmia. In addition to the above, daytime and nighttime LST have increased during the warm period of the year as well as the air temperature on the lake. This increase increment evaporation, especially during periods when recharge is reduced due to seasonal dry. Although precipitation has increased at the end of spring, but with increasing temperature, precipitation increases with increasing evapotranspiration and water requirement of plants is neutralized. Therefore, the simultaneous change of environmental and atmospheric parameters can be considered as aggravating the conditions of hazardous events in this basin.ConclusionBased on the evaluation done in this study, it can be concluded that the basin of Lake Urmia is vulnerable. Therefore, the three main and significant effects of environmental variability in these areas are increasing ground temperature, vegetation and reducing water resources. The result of these conditions on the one hand and the increase of water needs of plants on the other hand will increase the stress on water resources, especially groundwater. Decreasing the lake surface and increasing consumption and reducing water resources can lead to the spread of bare surfaces and the occurrence of dust.
Urban Planning
Rasoul Ghorbani; Hamid Hodjati
Abstract
IntroductionIn Iran, a comprehensive urban plan has been prepared and implemented for almost 5 decades. The most prominent plan that has completely dominated the country's urban planning system from the early 1960s to the late 1990s and until now (2019) relatively absolutely. Gradually, with the revelation ...
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IntroductionIn Iran, a comprehensive urban plan has been prepared and implemented for almost 5 decades. The most prominent plan that has completely dominated the country's urban planning system from the early 1960s to the late 1990s and until now (2019) relatively absolutely. Gradually, with the revelation of many weaknesses of this plan, which in combination with the structural weaknesses of the country's urban planning system became more obvious and prominent, the grounds for changes in the system of urban development plans emerged and based on a review of urban development plan services, and its concepts were revised. The inability of traditional management and thus traditional urban development plans to meet the needs of cities had revealed that urban management needed new patterns. Specifically, with the proposal of preparing structural-Strategic urban plans instead of comprehensive urban plans and preparing detailed basic, local and thematic plans instead of traditional detailed plans in the middle of the 1990s, a serious step was taken to change the old trend and prepare and implement so-called new plans. Specifically, after the evaluation of the Ministry of Urban Development of comprehensive urban plans in 1999, it was suggested that Structural-Strategic plans be prepared as a pattern for some metropolises, and based on this proposal, two research plans were defined to investigate the issue: one called process revision, and the content of urban plans and others called global experiences in structural and strategic planning.Data and MethodThe present article is a kind of basic-applied and developmental research and has considered descriptive and comparative-analytical methods to achieve its goals. Specifically, the research in the form of an analytical and descriptive approach, first begins with the study of urban development plans in Iran and the world, and with a detailed documentary study, the foundations of the idea are formed. Then, by analytical study of the plan (content analysis) and in a comparative study with urban development plans of developed countries, indicators and data as well as the main principles and objectives of the extracted plan are compared.Results and DiscussionStructural-Strategic plans of Iran, as its title shows, have a two-part structure (structural and strategic), but according to the authors, they have three parts: strategic part, structural part and comprehensive part. Identifying some of the essential weaknesses of this hybrid plan, roughly indicates that the plan is not able to fully and optimally achieve its goals. In addition, the managerial dilemma has dominated the plan from the beginning. The Supreme Council of Urban Planning and Architecture has not reached a complete conclusion and has not fully accepted the Structural-Strategic plan or the name given among the experts, that is, the Comprehensive Strategic Structural plan. Some parts are not approved and some are not approved, and in this situation, consulting engineers and municipalities are naturally confused, and to avoid this situation, the general tendency of the urban planning system to devise and prepare the previous pattern, i.e. Comprehensive, is diverted. Examination of some internal samples clearly showed that this combination has led to a kind of substantial rupture and avoidance of feasibility. It can be said with negligence that only the structural part has been prepared in a way that has more excitability. The existing studies section has many similarities with this section in the comprehensive pattern and unfortunately has the same problems. The strategic part of the plan is not well developed and in accordance with the principles of Western strategic plans (the purpose is not to hide localization, but the issue of not paying attention to the basic principles), and it is enough to plan general slogans at all levels. The structural part also plays a significant role in marginalizing it with a complete break from the strategic part. Of course, the original planners of this hybrid plan do not claim that this hybrid plan. But it is not clear on what argument this should be accepted!ConclusionThe Structural-Strategic plan emerged from the mid-1990s in response to the many weaknesses of the Comprehensive plan in the Iran's urban planning system. However, the studies of the present article reveal the construction of an incomplete combination of different plans with a clear and hidden focus on the Comprehensive plan and is not able to lead cities to the necessary utility. However, even in this situation, tips and suggestions can be made to correct things. Although it will not be the final solution. Suggestions such as simultaneous preparation of theoretical and operational parts of the structural-strategic plan to avoid inconsistencies and problems due to the time interval between the preparation of the two plans -the gap between the preparation of the structural-strategic and detailed (local) plan-. To achieve this goal, general and detailed studies of the plan can be done in parallel; A general overview of the so-called structural-strategic plan, by measures such as increasing the relationship between the strategic and structural sectors in the Structural-Strategic plan and if Inability to do so, removing the strategic part from the structural part or vice versa and focusing on only one part; Return of this Plan to the basic principles of the structural plan (the structural part of the plan in Iran is not faithful to the original pattern); More detailed presentation of thematic and local plans with further investigation, Establish laws to delegate more authority to local authorities to prepare and approve urban development plans, and beyond these proposals, propose a plan to replace the structural-strategic plan until the country is ready to prepare and implement the optimal strategic pattern, can well fill the gap between the current situation and the desired situation. Based on this, a proposed plan with the title of comprehensive strategic plan or comprehensive-strategic plan was compiled by Hamid Hodjati (one of the authors of this article), which is specifically based on his studies on various urban development plans in Iran, studies on global examples of strategic pattern and his opinions and views from this studies.
Climatology
Hossein asakereh; Seyed Abolfazl Masoodian; Fatemeh Tarkarani
Abstract
Introduction
According to previous investigation and examining climatic elements, the hypotheses of global warming and consequently, global climate change is confirmed by majority of climatologists society around the world. The global changes probably continue for the next decades. The changes in climatic ...
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Introduction
According to previous investigation and examining climatic elements, the hypotheses of global warming and consequently, global climate change is confirmed by majority of climatologists society around the world. The global changes probably continue for the next decades. The changes in climatic elements, by and large, categorized into two types; trends and variation. The trends refer to long term changes, whiles variations indicate vary time interval changes including oscillation, phase, jump (sift), and persistence.
Precipitation is one of climatic elements which can properly reflect chaotic behavior of climate system, and illustrate the nature of changes in the system. Trends, Oscillation, and persistence in this element are investigated in national and international scale, whilst the decadal variations as an index of climate variation can contribute to the current literature. In current study we attempted to illustrate an objective feature of precipitation characteristics and its anomalies over four recent decades by using Asfezari National Dataset (AND).
Data and Methods
In the present study, the gridded precipitation data of the third version of AND with spatial resolution of 10×10 km during the time period of 1970/3/21 to 2016/3/19 (46 years including 16801 days) is used. This dataset adopted from 2188 synoptic, climatology, and rain gauge stations and subjected to interpolation by using Kriging interpolation method. The dataset covers an area from N and E. Accordingly, a pixels cover the area for 16203 days. Consequently, the dataset includes dimensions.
General spatial features of Iran precipitation for the whole under investigation period was studied based on climatological annual precipitation. Next, the same characteristics calculated for four decades ending up to 2016/3/19. Finally, for every decade the anomalies of precipitation in compare with the whole understudy period and its previous decades calculated in order to discover the spatial pattern of decadal fluctuation in precipitation.
Discussion
General characteristics of annual precipitation
Annual mean of precipitation over Iran is 250.5 mm. Due to decline in temperature contrast and strength of fronts in the Mediterranean cyclones, as a main source of precipitation in Iran, the annual precipitation over Iran decreases from west to east, and from north to south.
The annual precipitation in 63.2% of Iran is lower than the climatic annual mean. The annual mean of precipitation in this area which generally located in east and south of the country is approximately 150.5 mm. Thus, the total precipitation in this area is equal to the total precipitation in the rest 36.8% of the country which its annual precipitation is more than the annual precipitation in the country, 422 mm. The spatial variation of precipitation is confirm by other statistics, for instance, skewness, kurtosis, the extreme threshold indices. For instance, a large part of Iran (26.73%) includes 100-150 mm annual precipitation, whiles the precipitation in 15.8% of the country reaches to 150-200 mm. Parts of northeast of Iran, and the coast of Persian Gulf and Oman Sea in the south, in addition to southern slops of Alborz mountain chain experience a precipitation amount of lower than 100 mm. In contrast to the above-mentioned dry regions, the (approximately) wet regions include limited areas for each precipitation class. For example, only 9.1% of the country characterized with 500 mm of precipitation, while the classes of 200-300, 300-400, and 400-500 comprise 20.62, 12.64, and 6.11 percents of the country, respectively.
Decadal variation of precipitation
In current section the spatial distribution and statistical features of precipitation in each decades was illustrated. The following list includes our finding of statistical - graphical analysis of precipitation in four successive decades:
1) The difference between spatial mean and median of annual precipitation increased from the first to the last decades. The increasing in this characteristic refers to increase in spatial asymmetrical distribution of precipitation over the country.
2) A comparison between spatial distribution of precipitation maps showed that generally, the areas experienced precipitation above the decadal and whole period average are decreased from the first and last decades.
3) The increase in spatial skewness from the first decade to the last decade is another evidence of increasing in precipitation spatial differences.
4) The last but not the least finding is the changes in the extreme threshold indices. From the first to the last decade, the range of 10th and 90th percentiles have increased.
Conclusion
Previous studies depicted that the amount of Iran precipitation has decreased over recent decades. In order to investigate the role of each decade in the decreasing values, the gridded precipitation data of the third version of AND with spatial resolution of 10×10 km during the time period of 1970/3/21 to 2016/3/19 (16801 days) is used. General spatial features of Iran precipitation for the whole under investigation period was investigated based on climatological annual precipitation. Next, the same characteristics calculated for four decades ending up to 2016/3/19. Finally, anomalies of precipitation in compare with the whole understudy period and previous decades calculated in order to discover the spatial pattern of decadal fluctuation in precipitation.
Our finding showed that by and large, precipitation has decreased over recent decades. The changes has been more pronounced in southern and northern coastal area, western slopes of Zagros mountain chain, and northern slopes of Alborz mountain chains. Previous researchers attribute these changes to changes in humidity advections in recent years.
Climatology
mehdi asadi; Ali Mohammad Khorshiddoust; Abbas Ali Dadashi Roudbari
Abstract
Introduction As the stations measuring precipitation continuously are not regularly available, the best solution should be to investigate the points without statistics using optimal methods. Among these methods, we can mention geostatistical methods. Geostatistical methods have been approved as appropriate ...
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Introduction As the stations measuring precipitation continuously are not regularly available, the best solution should be to investigate the points without statistics using optimal methods. Among these methods, we can mention geostatistical methods. Geostatistical methods have been approved as appropriate ways for studying precipitation data and estimating precipitation regions. Results of many studies have shown that geostatistical techniques are more accurate than conventional interpolation methods. Statistical context can also be used for precipitation variability. Accurate estimation of the spatial distribution of precipitation requires a dense and regular cell network. The spatio-temporal variation of precipitation is one of the most important issues of applied climatology, so the main purpose of this study is to monitor the spatio-temporal variation of precipitation in Iran in seasonal context by the application of the mentioned techniques. Data and Methods In this study, the common statistics of 125 synoptic stations in the country with the statistical period of 30 years (1980-2010) have been used. Also, the station data were generalized to the 15 km cell spaces using the Kriging interpolation method in ArcGIS 10.2.2 software. To speed up the computational process, the capabilities of GS + software were used to fit the variogram, and ArcGIS software was used to map the precipitation regions of the country. In order to study the pattern of precipitation, spatial autocorrelation techniques (local Moran and global Moran) were used. Also, the skewness coefficient (G1) and the peak degree coefficient (G2) were calculated separately for each of the months studied. Cluster and non-cluster analyses and hot spot method were used to study the patterns and spatio-temporal variations of precipitation. Cluster and non-cluster analysis, also known as Moran local Anselin index is an optimal model for showing the statistical distribution of phenomena in space (Anselin et al, 2009: 74). For cluster and non-cluster analyses for each complication in the layer, the value of the local Moran index score, which represents the significance of the calculated index, was also calculated. Results and Discussion The value of the global Moran index for all 4 studied seasons and the annual total is above 0.95, which indicates the pattern of high clusters of precipitation in the country at the level of 95 and 99%. However, the highest Moran index in the world with a value of 0.970356 is related to the winter. Statistics for each of the five decades studied are high, between 255 and 261. Therefore, based on global trends, it can be inferred that the annual changes in precipitation in the country follow a very high cluster pattern. Consequently, due to the high value and low value, the hypothesis of no spatial autocorrelation between data in each of the five decades can be rejected. If precipitation were to be normally distributed in space for different seasons in the country, the global Moran index would be -0.000139. Moran's spatial autocorrelation only determines the type of pattern. For this reason, to show the spatial distribution of the pattern governing the distribution of precipitation in Iran, local Moran has been used during the studied periods. In winter (36.56%) there was no pattern or in other words it lacked spatial autocorrelation. This amount increased by 1.14% for spring and reached 37.70. This amount has increased significantly in summer, so that it has increased by 47.04% compared to spring. It has reached areas with no spatial autocorrelation in autumn (41.92) and winter (36.56). LL precipitation patterns have been distributed in the five studied periods with values of 36.53, 0, 34.64, 35.31 and 38.29% in the country, respectively, and in the form of nationwide spots in the eastern, southeastern and central regions. Precipitation values with negative spatial correlation in summer had the highest value (84.74%) and the lowest annual average (35.06%). However, values with high rate or positive spatial autocorrelation in all five studied periods were limited to the northern regions of the country, the highlands of Alborz, Zagros and had significant fluctuations in some parts of the country. Local Moran Anselin statistics have been able to well determine the process of precipitation (Masoudian, 1390: 97) and the era of windbreak slopes as well as adjacent areas with climatic contrasts such as north-south slopes of Alborz and slopes of east-west Zagros. Due to the complexity of precipitation patterns in the country, spatial statistics can well explain precipitation patterns. The general results of this statistic (local Anselin Moran) indicate that the amount of rainy areas in the country has been reduced during five study periods. It should be noted that most of these reductions were related to the Zagros region, the southeast of the country and the northern regions of Khorasan. Conclusions Iran has special conditions in terms of precipitation due to its vastness with respect to latitude and longitude, the configuration of unevenness and exposure to air masses. The general structure of precipitation in Iran is affected by latitude, altitude and air masses, so that with the change of any of these factors, precipitation will also change. In other words, the general conditions of precipitation are a function of latitude and altitude, and other factors such as water areas and land cover, which are referred to as local factors, play a role in the formation of Iranian precipitation. In the present study, spatio-temporal analysis of Iranian precipitation has been done using a new method of spatial statistics. For this purpose, high and low clustering methods, local and global Moran, hot spots and cluster and non-cluster analyses have been used. The present study focuses on the assumption that precipitation in Iran follows a cluster pattern and the pattern of precipitation distribution is itself a function of internal and external conditions. To achieve this goal, the average seasonal and annual precipitation statistics of 125 synoptic stations in the country during the statistical period of 1980-2010 were used. Then, to apply the methods used in this research, the capabilities of GIS were used. The results of the global Moran method and the K-function of some distances showed that the annual changes in precipitation in Iran follow the pattern of high clusters. According to spatial autocorrelation analyses, the areas with negative spatial autocorrelation in all studied periods are related to the southeast, the coasts of the Oman Sea to Abadan and parts of the northeast of the country. Areas with positive spatial autocorrelation were often located on the southern shores of the Caspian Sea and the Zagros strip. In all the studied periods, less than one quarter of the country's area lacked a significant spatial autocorrelation pattern. Spatial analyses showed that Iran's precipitation patterns are divided into two precipitation spots of southern tabs (low precipitation spot LL), and Caspian coasts west and northwest (precipitation spot HH). The results also indicated that during the period under study, low precipitation spots (negative spatial autocorrelation) had much more frequency than precipitation spots.
All other Geographic fields of studies , Interdisciplinary
Firouz Jafari; afshar hatami; sonya karami
Abstract
Introduction Economic growth is one of the goals pursued by every country, and this is because of the many benefits that come with the growth process. According to World Bank reports, more than 80 percent of people live in developing areas. Unfortunately, in developing countries such as Iran, balanced ...
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Introduction Economic growth is one of the goals pursued by every country, and this is because of the many benefits that come with the growth process. According to World Bank reports, more than 80 percent of people live in developing areas. Unfortunately, in developing countries such as Iran, balanced development has not taken place, which has created regional inequalities and economic divisions between regions. The increasing inequalities between different regions of a country indicate that part of the country's population is not benefiting from the consequences of economic growth and development. Theoretical framework The discussion of development and underdevelopment is one of the most challenging issues in today's world that is influenced by various spatial, temporal factors, and the varying value of different criteria in measuring development. The expansion of development concepts and policies has led the past decades called the era of development. This era has begun in the mid-20th century. Many indicators have been provided for measuring development and underdevelopment; however, based on most thinkers, especially thinkers of the 20th century, economics is a significant development factor. Moreover, there is a close relationship between human and the economy; as economic development cause the development and improvement of human living conditions, humans are the main factor of economic growth and development. Nevertheless, economic development happens when all regions of a country benefit from that. Therefore, to achieve comprehensive economic development, economic policymakers must create a kind of economic balance and cohesion in different regions and provinces so that with coordinated economic growth, the economic development differences can be solved in provinces of Iran. Methodology A descriptive-analytical approach was used in the present study. The required data from the statistical yearbook of 1395 have been collected in the form of 30 indices. Shannon entropy, coefficient of variation, and Vikor were used for weighting, distribution analysis, and developmental level determination, respectively. ArcGIS software was also used to display the map. Results and Discussion The coefficient of variation was used to determine the status of the distribution of indicators in the provinces. According to the results, about 11 indices have a coefficient of variation above 1, and two indices have a coefficient of variation above 0.9, indicating a lack of balanced distribution of economic indices in the provinces. There are the highest inequalities between the indicators of incoming tourists, durable housing, and mining workers with 2.00, 1.55, and 1.54 scores, respectively. In contrast, there are the lowest inequality levels between the indicators of male economic participation, economic participation, and working population with 0.6, 0.7, and 0.7 scores, respectively. Overall, 36.67% of the indices scored above 0.9 indicate inequality between more than two-thirds of the indices studied in the provinces. Based on economic indicators, the Q average for 31 provinces was 0.76, which is above average. Isfahan province with Q equal to 0.253 is at the highest level, and Tehran and Khorasan Razavi provinces are in second and third place with Q equal to 0.322 and 0.434, respectively. In contrast, Ilam province is at the lowest level, with Q equal to 0.996. Chaharmahal and Bakhtiari and Ardabil provinces are ranked second and third most economically deprived, with Q equal to 0.977 and 0.964, respectively. Conclusion The results of this study showed that mainly central and populated provinces, including Isfahan, Khorasan Razavi, Tehran, Kerman, Fars, East Azarbaijan provinces had a higher level of development, and the rest of Iran provinces had medium and lower economic development level. Among the 11 provinces with low development level are Gilan, Zanjan, Kurdistan, Alborz, Lorestan, Hamadan, Golestan, North Khorasan, Bushehr, Hormozgan, Sistan and Baluchestan and 7 provinces with lower development including Ardebil, Qazvin, Qom, Kermanshah, Ilam, Chaharmahal and Bakhtiari, Kohgiluyeh and Boyer Ahmad require special attention and efficient policies and programs for faster and more effective economic development. Overall, 19.35% of provinces were at the highest economic development level, about 22.58% at a medium level, 35.48% at a low level, and 22.58% at a lower level. The interesting point is that the absence of any of the provinces in Iran at a high level of economic development. This point clearly indicates the inefficiency and hierarchy of economic development and other aspects of the imbalance of economic development in Iran.
Climatology
Mostafa Karimi; Faramarz Khoshakhlagh; ali akbar shamsi por; fahimeh noruzi
Volume 23, Issue 69 , December 2019, , Pages 233-255
Abstract
Large-scale circulation patterns are controlling climatic conditions and especially precipitation of the area. The purpose of the study is investigating the relationship between circulation patterns of Arabian subtropical anticyclone and Iran precipitation. For this reason, was used re-analysis data ...
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Large-scale circulation patterns are controlling climatic conditions and especially precipitation of the area. The purpose of the study is investigating the relationship between circulation patterns of Arabian subtropical anticyclone and Iran precipitation. For this reason, was used re-analysis data of geo-potential height form European Center for Medium-Range Weather forecasts (ECMWF), with spatial resolution of 1*1 degree and correlation distance cluster analysis. Circulation patterns at 30 to 80 degrees the East longitudes and5 to 30degrees north latitudes and the period of11years (2000- 2010) was calculated. The results showed that the patterns in terms of occurrence were divided the patterns of the cold period, the warm period and the transition period. During the cold period anticyclone is located at down latitudes on the Arabian sea and Gulf of Aden and have precipitation more areas of Iran that maximum amount of precipitation is related to the second pattern. In the patterns of transition period Arabian anticyclone sent a southwest clockwise current in to the trough East Mediterranean is effective in the occurrence of precipitation in the area of North and Northwest of the country. In the patterns warm period the anticyclone caused the anticyclone conditions on country and has been as a barrier to entry precipitation systems.
Climatology
Behrooz Sari Sarraf; Shoaieb Abkharabat
Volume 23, Issue 68 , September 2019, , Pages 179-193
Abstract
As a core of wind speed, Low Level Jet (LLJ) of the Persian Gulf is made on the Persian Gulf and its surrounding in the low levels of the atmosphere during the hot period of the year. Known as north wind, this jet appears in the body of a more extensive current of wind with the northern, northwestern, ...
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As a core of wind speed, Low Level Jet (LLJ) of the Persian Gulf is made on the Persian Gulf and its surrounding in the low levels of the atmosphere during the hot period of the year. Known as north wind, this jet appears in the body of a more extensive current of wind with the northern, northwestern, southern, southeastern direction. North wind often blows from the mountainous regions of Turkey and Iran to the southern regions. Except for topographic reasons, the formation of this wind is influenced by hollow topography of low regions of Mesopotamia and Khouzestan appearing as a corridor. Reaching the Persian Gulf, this phenomenon is intensified as the water area of the Persian Gulf is besieged as a low hollow by Zagros Mountains and Arabic Peninsula aggravating the wind.
Climatology
abdolreza kashki; sayed mohammad hosseini; farahnaz khoramabadi
Volume 23, Issue 67 , April 2019, , Pages 263-286
Abstract
Global warming is one of the current and future challenges for humankind which can have an impact on agriculture, transportation, water resources, energy production, architecture, heating and cooling needs of the building, plant phenology, etc. In this research, for the spatio-temporal analysis, the ...
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Global warming is one of the current and future challenges for humankind which can have an impact on agriculture, transportation, water resources, energy production, architecture, heating and cooling needs of the building, plant phenology, etc. In this research, for the spatio-temporal analysis, the need for cooling day was used from daily data of minimum temperature and maximum temperature of 16 stations in the north east of the Iran during the period of 20 years (1996-2015). First, data matrices were created in the MATLAB software with an S-dimensional array (7035*16), where are the rows, representing time (day) and columns, representing the locations (stations). Finally, it was calculated of cooling degree day per month and plotted spatial mapping in ArcGIS. The results showed that significant and reverse correlation between altitude and latitude with cooling day requirements in all warm months of the year, also according to the need for cooling degree day, the Khorasan area can be divided into six climatic groups. The most need for cooling with more than 500 degrees of day is in the southern and lowlands of the area and the least need for cooling are located in the northern and highlands part. So that the highest percentage of need for cooling day degrees in April and May white %27.5, related to the semi-cold climate group; In June with %24.5; in July %23.7; in august %22.4 and in September whit %22.5, Belongs to the cold climate group. Also, the study of the process of cooling needs suggests that in April most of the stations lack a significant trend, and only stations in the north and south of the region have a declining trajectory. In September, there is also a drop in cooling needs at most stations.
Climatology
Hossein Asakereh; Ali shahbaee kotenaee
Volume 22, Issue 64 , September 2018, , Pages 211-228
Abstract
Pervasive cold days are one of the abnormal continental events that have a lot of effects on environment and human activity. These events are created as a result of formation of complex atmospheric patterns. In these patterns, knowledge of how these atmospheric systems interact can be very useful in ...
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Pervasive cold days are one of the abnormal continental events that have a lot of effects on environment and human activity. These events are created as a result of formation of complex atmospheric patterns. In these patterns, knowledge of how these atmospheric systems interact can be very useful in prediction of the similar conditions and reduction the contingency damages. On this basis in this present research, it has been tried to analyze the earth's temperature conditions and dynamic and synoptic conditions of different levels of atmosphere on 21 January 1964 as pervasive cold day in Iran by using data from minimum temperature gained in different parts of the country and also the atmospheric data from 1960 to 2010. In this day 98.4 % of the area has been affected by the cold. The results of synoptic and dynamic analysis of atmospheric systems that creating the cold of this day showed that created a blocking system in west and center of Europe and establishment a low height system in north of Russia and the opposite movements of these two systems to each other has caused that cold polar air from northern Scandinavia have moved to Iran. It has also been recognized that height factor has performed an important role in cold extremity in this day across the country.
Climatology
Golam Abbas Fallah Galharei; mehdi asadi
Volume 22, Issue 64 , September 2018, , Pages 229-246
Abstract
This study aims to identify the spatial autocorrelation and spatial variation of sunshine hours in Iran. For this purpose, the sunshine hours to form a network database have been made in Iran. The data from the base of a 30-year period, the daily period from 1/01/1982 to 12/31/2012 AD to the present ...
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This study aims to identify the spatial autocorrelation and spatial variation of sunshine hours in Iran. For this purpose, the sunshine hours to form a network database have been made in Iran. The data from the base of a 30-year period, the daily period from 1/01/1982 to 12/31/2012 AD to the present study, and intercellular dimensions of 15 × 15 km area stretching is studied. In order to achieve the sunshine hourly changes within a year, the sunshine of the Iran of spatial statistical methods, such as spatial autocorrelation global Moran, Moran's index of local Insulin, and hot spots was used by using the programming environment GIS. The results of this study showed that the spatial and temporal variation in sunshine hours in Iran is High-cluster pattern. In the meantime, based on local Moran and hot spots, South, South East and Central synoptic stations representing the provinces of Sistan and Baluchistan, Kerman, Shiraz, Isfahan and Yazd have positive spatial autocorrelation pattern, full sun pattern, and parts of North, North East and North West representing synoptic stations in Tabriz, Mazandaran, Mashhad and Semnan have a negative spatial autocorrelation, low sun pattern. In the study period, in most cases, a large part of the Iran, almost half of the total area, has had no significant pattern or spatial autocorrelation
Climatology
amanollah fathnia; hamid rahimi; Shoaieb Abkharabat
Abstract
Siberian high pressure (SHP) is synoptic system that during the autumn and winter seasons on Asia is religious (Msaudian and Kaviani, 2009: 15). In the cold term of the year, the vast Siberian territory due to the clear sky and away from water sources, the more energy through the long wave radiation ...
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Siberian high pressure (SHP) is synoptic system that during the autumn and winter seasons on Asia is religious (Msaudian and Kaviani, 2009: 15). In the cold term of the year, the vast Siberian territory due to the clear sky and away from water sources, the more energy through the long wave radiation loses, thereupon the around air of land gradually adjacent to becomes cold high-pressure center.
Climatology
Yousef Ghavidel Rahimi; Manuchehr Farajzadeh; masood salehian
Abstract
Nowadays, Climate change is a hot topic engaging the scientists around the world as a cause for future human and environmental crises. It has been generally accepted that the main cause for climate change should be increases in the content of atmospheric carbon dioxide due to excessive burning of fossil ...
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Nowadays, Climate change is a hot topic engaging the scientists around the world as a cause for future human and environmental crises. It has been generally accepted that the main cause for climate change should be increases in the content of atmospheric carbon dioxide due to excessive burning of fossil fuels, esp. in industrial countries. In the 19th century, scientists realized that gases in the atmosphere cause a "greenhouse effect" which affects the planet's temperature. These scientists were interested chiefly in the possibility that a lower level of carbon dioxide gas might explain the ice ages of the distant past. At the turn of the century, Svante Arrhenius calculated that emissions from human industry might someday bring a global warming. Other scientists dismissed his idea as faulty. In 1938, G.S. Callendar argued that the level of carbon dioxide was climbing and raising global temperature, but most scientists found his arguments implausible. It was almost by chance that a few researchers in the 1950s discovered that global warming truly was possible. In the early 1960s, C.D. Keeling measured the level of carbon dioxide in the atmosphere: it was rising fast. Researchers began to take an interest, struggling to understand how the level of carbon dioxide had changed in the past, and how the level was influenced by chemical and biological forces. They found that the gas plays a crucial role in climate change, so that the rising level could gravely affect our future.
Climatology
Reza Mokarian; Hossein Sedghi; Samira Nemati; Hossein Babazadeh
Abstract
Evaporation is the important factor that affects temperature, drought severity and water storage in the hydrological cycle and plays an important role on managing the water resources projects such as agricultural irrigation. Classification of datasets is useful for concisely system modeling purposes. ...
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Evaporation is the important factor that affects temperature, drought severity and water storage in the hydrological cycle and plays an important role on managing the water resources projects such as agricultural irrigation. Classification of datasets is useful for concisely system modeling purposes. By classification, a large number of datasets is reduced to a small number of groups. In the field of hydrological systems, classification of meteorological stations into homogeneous groups will be useful to consider a different scale of measure, which is suitable to each group. Such classification can lead to choice methods appropriate for each group for management of water resources in various regions. Classification will also be useful for prediction of events such as droughts. Moreover, in the case of estimating missing data, the corresponding data of the representative station determined using a classification technique can be successfully substituted (Raju and Kumar 2007). stations. Dikbas et al. (2011) applied the FCM method to classify the precipitation series and identify the hydrologically homogeneous groups in Turkish. Regional homogeneity test results showed that regions determined by the FCM approach are sufficiently homogeneous for regional frequency analysis. In the present study, the practical applicability of two classification methods, namely fuzzy c-means (FCM) cluster analysis and Kohonen artificial neural networks (KANN), is examined for grouping 97 evaporation stations in Iran into homogeneous groups. The rest of the paper is organized as follows. First, a description of the case study is presented. After introducing the applied methods, results obtained are presented and discussed and conclusion drawn.
Urban Planning
Iman Ghalandarian; Hashem Dadashpoor
Abstract
Spatial patterns of migration in different periods to take a different spatial forms, in a particular time and place so that cities can immigration / high transmittable experience. Unbalanced patterns of immigration and settlement concentrated around particular it usually has important economic, social ...
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Spatial patterns of migration in different periods to take a different spatial forms, in a particular time and place so that cities can immigration / high transmittable experience. Unbalanced patterns of immigration and settlement concentrated around particular it usually has important economic, social and political activities are leading to the formation of the spatial arrangement is different from other areas. This paper aims to identify spatial patterns of migration between city and country in 1385 and 1390 and to identify the characteristics and spatial patterns of dominant done. The research method used is descriptive analysis and data on population and housing census used different techniques have been used for analysis.The results show that the municipalities located in the border areas that are geographically on the periphery of the country has a high origin and the majority of the host city at the center of the country. The area is also the largest area of the country (61 percent of the country) in the city that have high immigration (95 city). 80 city high that only 3% of the area of origin into account. Other city had the lowest dynamics of immigration (78 city). These findings suggest that the center-periphery relations in the country is still in need of policy to achieve regional balance in the country''s planning system.
Yousef Gavidelrahimi; Manochehr Farajzadehasl; Mehdi Alijahan
Abstract
Today, global warming effects on various aspects of the Earth are no secret to anyone. Because of this, the research ahead is done for the detection of global warming on minimum temperatures, monthly and periodic (hot and cold) as well. For this study, two groups of data, temperature data of 17 synoptic ...
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Today, global warming effects on various aspects of the Earth are no secret to anyone. Because of this, the research ahead is done for the detection of global warming on minimum temperatures, monthly and periodic (hot and cold) as well. For this study, two groups of data, temperature data of 17 synoptic stations and corresponding amounts of data in global temperature anomalies were figured out over 60 years period of time (1951 to 2010). Goals, the Pearson correlation method for detecting relationships between data, linear and polynomial regression for trend analysis time series data , To illustrate the correlation between the spatial distribution of temperature data with global warming stations nationwide Geostatistical model Finally, non-parametric test for detecting significant temperature change Man - Kendall were used. Based on the results, apart from Khorramabad and urmia stations that have negative relation with global warming and Hamadan and Kerman stations that do not show any significant relationship with global warming, global warming is seen as a positive influence on the other stations. Caspian Bank stations than any other stations in the cold months of global warming have much more influence. Checking the changes of minimum temperature trend showed a significant change in several months. In the warm months the maximum temperature variability is seen in the southern stations of Ahwaz, Abadan, Bushehr and Shiraz. Results obtained from the survey period (hot and cold) minimum temperature, indicate a greater influence global temperature anomaly on the minimum temperatures are warm period of year. During the warm period, southern stations have had the highest influence on the station and during the cold period Caspian Bank stations have had the highest relationship with it. The changes were made based on both periods the obtained results are clarity significant.
Climatology
Hosein Asakereh; Mehdi Doostkamian
Abstract
The purpose of this study was to climate regionalization precipitation water atmospheric Iran. Therefore, the pressure data and specific humidity of the NCEP / NCAR database during 1950-2010 dependent of the United States National Atmospheric and oceanographic organization was extracted and analyzed. ...
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The purpose of this study was to climate regionalization precipitation water atmospheric Iran. Therefore, the pressure data and specific humidity of the NCEP / NCAR database during 1950-2010 dependent of the United States National Atmospheric and oceanographic organization was extracted and analyzed. For the calculation used software programming environment of Matlab and Grads software and Surfer software used to perform graphics operations. In the study for the perceptible water climate regionalization use from cluster analysis and in order evaluate the results, used of discriminant analysis. In the data archive mean and Coefficient of Variation precipitation water month review and analysis the method cluster analysis ward composition, than dendrogram graph recognized three regionalization climates: a) climate regionalization whit high precipitation water, b) climate regionalization whit median precipitation water. b) Climate regionalization whit low precipitation water. The result archives from discriminant analysis indict that 98.24% from of pixels doing so as true in relative group.
Geotourism
maryam bayati khatibi; shahram maleki; dorna ghafari; soraya hadi
Abstract
Climate as a Geographical phenomenon, have a strong interrelationship With Tourism and development Purposes and goals Tourism. Photo Tourism as a main subbranchs of Tourism, is attended case for countries with suitable climate and with long shine time at all Seasons. Unequal distribution of sun radiation ...
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Climate as a Geographical phenomenon, have a strong interrelationship With Tourism and development Purposes and goals Tourism. Photo Tourism as a main subbranchs of Tourism, is attended case for countries with suitable climate and with long shine time at all Seasons. Unequal distribution of sun radiation on surface of the world is main reason that people travel from high latitude with low shine time to low latitude with long shine time. In this paper is study tourism climate comfort for all seasons of years, by use of TCI index then, is calculated of shine time for all seasons .In this Research in order to zoning of suitable photo Tourism regions of Iran, and also assessment climate comfort tourism at during all seasons at different time of year, is used fuzzy methods and fuzzy Gamma. The suitable climate condition or comport climate is determined by using of fuzzy methods. The results of this study are show that is five regions in maximum and four regions in minimum is exist in suitable photo Tourism of Iran. These regions is represented same property of comfort climate respect and shine time in during time of year. In other term, these regions have very suitable photo Tourism aspect at many time of year.
Climatology
Bohlul Alijani; Ali Bayat; Mehdi Doostkamian; yadollah Balyani
Abstract
Precipitation is one of the most essential and variable climate components whose understanding has long been a concern for climatologists. The main objective of the current paper is to investigate and analyze the precipitation cycles in Iran. In order to realize this objective, the annual precipitation ...
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Precipitation is one of the most essential and variable climate components whose understanding has long been a concern for climatologists. The main objective of the current paper is to investigate and analyze the precipitation cycles in Iran. In order to realize this objective, the annual precipitation data of isometric station of Iran were extracted. These data have been collected by the country’s meteorological organization since the establishment of the station until 2008 which adds up to more than 40 years of statistics. Then, in order to investigate and analyze the precipitation cycles, spectral analysis (co-structural analysis) was utilized. Regarding the calculations, the programming utilities of Matlab were used and the Surfer software application was exploited for drawing operations. The results obtained from analyzing the cycles show that there are significant 2 to 3 year cycles, 3 to 5-year cycles, 2 to 6 year cycles and sometimes 11 or more- year cycles governing Iran’s precipitation patterns. Hence, in east and southeast of Iran, 3 to 5-year cycles are prevailing and in west and northwest 2 to 3-year cycles are dominant and finally in north east 2 to 6-year cycles are customary. The most numerous and the most variable cycles happen in south and south east, mainly due to the mountainous regions of Zagros as well as the proximity to Persian Gulf. The north western regions, much like the southwestern regions, indicate variable cycles due to the mammoth mountains of Sabalan and Sahand. Moreover, the presence of those cycles which have a return period equal to the statistical period has been seen in various parts of Iran, which indicates a precipitation trend in this country.
Climatology
Yousef Ghavidel Rahimi; Manochehr Farajzadeh Asl; Daryoush Hatami Zarneh
Volume 20, Issue 56 , August 2016, , Pages 239-255
Abstract
The NCP as one of the effective teleconnection patterns in level of 500 hpa have an important role in thermal and hydro-climatic variability in East Mediterranean region. In this study to investigate the correlation between the NCP and maximum temperature fluctuations Iran for a 60 years period (1950-2010) ...
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The NCP as one of the effective teleconnection patterns in level of 500 hpa have an important role in thermal and hydro-climatic variability in East Mediterranean region. In this study to investigate the correlation between the NCP and maximum temperature fluctuations Iran for a 60 years period (1950-2010) have been studied. Pearson correlation analysis as the main method used in this study show an inverse relationship between maximum temperatures and selected stations and NCP index. This shows decrease of temperature in positive phase of the NCP and rise of temperature in negative phase. In terms of time correlation coefficients were calculated and showed a significant negative correlation between the temperature of stations and the NCP in months of January, February, March and almost direct relation most stations in August. At monthly interval in the monthly correlation between stations with 0.342 were computed in January. Seasonal correlation of shows a significant correlation of maximum temperatures in winter to be -0.212. In terms of period, the results indicate a strong correlation between cold period in most stations and mentioned index. Atmospheric circulation in 500 hpa at positive and negative phases showed in positive phase, settlement of deep trough on the Caspian Sea, Iraq, Turkey and Iran, and also the location of Iran in the eastern part of the trough axis on the other hand, indicates establishment of a ridge on the North Sea and Europe which leads to transfer of cold temperatures of northern Europe and its adjacence of polar section to Iran. But on the negative phase placement of Iran beneath the ridge axis leads to the creation of a barotropic atmosphere with weak zonal wind and warm temperatures to Iran. So with blowing warm air from Africa, Arabia and low latitude Iran's temperature rises.
