Zohreh Maryanaji; Sayyed Akbar Hosseini; Hamed Abbasi
Abstract
Extended Abstract Introduction Growing demands for energy, increasing living standards and increasing use of electrical energy along with the overheating of planet Earth, as well as environmental problems and threats to human health are among the issues that attract the world’s attention to the ...
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Extended Abstract Introduction Growing demands for energy, increasing living standards and increasing use of electrical energy along with the overheating of planet Earth, as well as environmental problems and threats to human health are among the issues that attract the world’s attention to the use of renewable energies. So, new energy resources, including wind energy, account for one third of the energy needed for countries in the annual planning. Since Hamadan is one of the provinces in Iran with severe winds with relatively good continuity, the use of this energy in wind turbines is indispensable for generating electricity at the provincial level, especially in impassable areas. Today, many dangers, including the threat of climate, change the Earth’s environment. This controls the methods that can reduce the use of renewable energies such as solar, geothermal, wind, etc. Strong and frequent winds are very important energy sources for many parts of the country. In this study, the average and maximum wind speed yearly energy (annually and seasonally) and its energy based on the data from nine synoptic stations in Hamadan province in the climate period of 2000-2014 have been analyzed and spatial velocity of wind speed and its energy in this region were studied. Materials & Methods: The length of the statistical period in the present study was 10 years. After checking the accuracy of the data, the mean and maximum of the seasonal and annual wind speed were calculated and drawn. Then wind energy was calculated using wind power density (watts per square meter), air density (g / cm3), wind speed (m/s). To investigate the spatial distribution of wind energy potential in Hamadan province based on the obtained information, the values were zoned using Kriging method in GIS. Finally, the probability of occurrence and the prediction of the return period of wind were calculated using the Log Pearson type 3 method. Results & Discussion According to the zoning plan, the maximum annual wind speed in the Hamadan is related to the southern parts of the province. Some parts of the province in Kabudrahang are accompanied by intense storms. In winter, maximum wind speed is determined by the instability of air and weather in areas of Hamadan province. The Average annual wind speed zoning pattern indicates that the east parts of Hamadan and some parts of Malayer and Razan have the highest average wind speed (above 3 meters per second), while in other parts of the province it is less than 3 meters per second. The Eastern part of Hamadan province (from the South east to the North east), are the windiest region of the province, and in most of the times of a year these parts have the potential of wind power production. Some regions of the Southwest are also capable of producing wind power during the year. Conclusion The role of topography on wind speed in Hamadan province is noteworthy. The mountainous regions of the province such as Hamadan, Nahavand and Asadabad are more exposed to the winds of the plains - mountains. Hot wind is also one of the meteorological phenomena due to the mountain effects, which is often found in the city of Hamadan. The East and parts of the city of Malayer, and especially in the Northern areas of the province with the highest average wind speed (above three meters per second) and the West and Southwest shown with minimum wind speed during the period specified. Most of the year, the most windy areas, Eastern and Northern regions of the province, have the ability to produce electricity from wind energy. Kabodarahang plain areas of the city of Razan have the highest wind energy potential in watts per square meter and the greatest potential for energy production from wind in Hamadan is in spring and autumn. In the studied area, Nojeh station (North of the province) with more than 18%, and then Malayer station (Southeast of the province) with more than 17%, have the priority for establishing wind turbines due to wind speed persistence. By studying the occurrence of wind speed in the meteorological stations of Hamadan province, some areas of the Razan plain and Kabudrahang are suitable for planning wind power usage.
Zohreh Maryanaji; Hamed Abbasi
Abstract
Abstract
Two important characteristics of Hamedan climate are irregular precipitation time and maximum 24-hour precipitation in the months of March (20th) and April (20th). This factor, namely severe rainfall, has increased the risk of flood in this province. The precipitation is snowy in the winter ...
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Abstract
Two important characteristics of Hamedan climate are irregular precipitation time and maximum 24-hour precipitation in the months of March (20th) and April (20th). This factor, namely severe rainfall, has increased the risk of flood in this province. The precipitation is snowy in the winter season, and the melting time accompanied by the rain, causes rivers to flood. The land’s lack of the crop and vegetation cover in other months of the year and the dryness of the soil and ..., increase the flood. Flooding factors are diverse in Hamadan province. Some of the most important factors influencing the flooding of an area are climate, inequalities of vegetation, etc. In this paper, maximum daily rainfall has been investigated in order to predict the amount of water that can be extracted from floods and to plan for management of the region’s water resources. For this purpose, on the basis of maximum 24-hour precipitation, the map of the elevation and rainfall gradient model and the rain map of the region for the return period of 2,10,25,50 with the ‘best statistical distribution’ method for the region (Gamble distribution) are estimated and zoned in the GIS environment (by Kriging method) and the probable daily precipitation decreases by the reduction in the return period.Accordingly, during the aforementioned return periods, the southeast and northwest regions of Hamadan province (Dasht-e-KaboodarAhang) have the most probable daily precipitation.The abundance of the number of floods in the province reflects the fact that the aforementioned regions have the highest numbers and the (the most terrible floods in the province (1987 flood in KaboodarAhang region). According to these maps, the eastern parts of the province have the least probable daily precipitation. The results of this study can be used in flood zoning and forecasting as well as planning and management of water resources in the region.
Zohreh Maryanaji; Hossein Karimi Javid; Yusof Sheykholmoluki
Volume 22, SEPEHR , July 2013, , Pages 12-16
Abstract
In the present article, Isfahan annual temperature parameters were analyzed to determine long-term time trend and its potential changes in 1976 to 2005 time period. To do so, any of the temperature data series received from the five weather stations (Isfahan, East Isfahan, Kashan, Kabutar Abad, Khor) ...
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In the present article, Isfahan annual temperature parameters were analyzed to determine long-term time trend and its potential changes in 1976 to 2005 time period. To do so, any of the temperature data series received from the five weather stations (Isfahan, East Isfahan, Kashan, Kabutar Abad, Khor) were investigated based on Mann-Kendall statistical tests and normal residuals cumulative curve. Based on the non-parametric Mann-Kendall method, maximum temperature in Kabutar Abad and Khor stations had increased significantly, while other stations lack a trend. Minimum annual changes also shows a relative increase in eastern stations and average temperature in East Isfahan and Kabutar abad stations have an increasing trend. Normal residuals cumulative curve which divide data into two domains has similar results. According to this method, temperature in kabutar Abad and East Isfahan stations have increased significantly. The results which indicate temperature increase in most provincial stations (especially central ones) can be applied to zoning and predicting future droughts along with planning and managing water resources in the area.
Zohreh Merianji; Hamed Abbasi
Volume 14, Issue 54 , August 2005, , Pages 47-50
Abstract
The phenomenon of flood in its current state in our country is caused more by the effects of interrupting the balance of natural ecosystems in the country than by the occurrence of low-probability precipitation. In the form that we can observe today, the occurrence of ordinary rainfall in most watersheds ...
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The phenomenon of flood in its current state in our country is caused more by the effects of interrupting the balance of natural ecosystems in the country than by the occurrence of low-probability precipitation. In the form that we can observe today, the occurrence of ordinary rainfall in most watersheds of the country causes flood. According to available statistics, in parts of the world, especially in Asia and the Pacific, flood damage accounts for the highest proportion of damages caused by natural disasters. Despite the fact that no comparative statistics on flood and earthquake damage in our country have been published so far, Iran is nevertheless considered a flood-prone country, having arid and semi-arid climatic conditions. The province of Hamedan is among the flood-prone areas of Iran due to natural and human factors contributing to the occurrence of flood. The occurrence of historic floods such as floods in 1987 and 1992 in this province illustrates this fact. Flood factors fall into two categories: natural factors including climatic conditions (repeated rainfall, snow melting, high temperatures ...), land features (slope, soil texture, etc.) and poor vegetation, and human factors. In Hamadan province, the above factors have in mutual cooperation caused conditions favorable to flood which are mentioned in this study.
Ali Akbar Sabzi Parvar; Zohreh Merianji; Abbas Karami
Volume 14, Issue 53 , May 2005, , Pages 48-52
Abstract
In order to study the temporal and spatial distribution of drought in Hamadan province, statistics of eleven of province stations for a period of 27 years was used, and after performing validation and homogeneity tests, it was normalized with drought by the Gibbs and Mohr method, and SPI index for years ...
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In order to study the temporal and spatial distribution of drought in Hamadan province, statistics of eleven of province stations for a period of 27 years was used, and after performing validation and homogeneity tests, it was normalized with drought by the Gibbs and Mohr method, and SPI index for years of drought occurrence in the province was determined. According to this, in the years 1996 and 1999 the most severe drought has occurred. After the dry years were determined based on the Gibbs and Mohr method, the related maps were drawn up to determine its dispersion across the province, and finally, using the ranking of these indices, the final map was drawn according to which the intensity of droughts decreases from east to west, namely, the eastern and central regions have been more susceptible to drought in comparison with other parts of the province.
Zohreh Merianji; Reza Borhani
Volume 12, Issue 47 , November 2003, , Pages 61-64
Abstract
Climate change is a general term that describes climatic discontinuity and rupture. In order to study temperature changes in Hamadan, temperature fluctuations in a statistical period of fifty years (1952-2002) have been investigated. According to a survey conducted in 1973, a sudden drop in the minimum, ...
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Climate change is a general term that describes climatic discontinuity and rupture. In order to study temperature changes in Hamadan, temperature fluctuations in a statistical period of fifty years (1952-2002) have been investigated. According to a survey conducted in 1973, a sudden drop in the minimum, and a sudden rise in the maximum, temperature were observed. According to the Mann Kendall test, there are significant changes in the three parameters of minimum, maximum and average temperature, including the decreasing trend observed in 1962, and this negative trend continued until 1992, and this year thereafter, an increasing trend of temperature can be observed. It should be noted that the maximum spring temperature is an exception, since in the year 1992 it is the beginning of cooling season. On the minimum temperature chart, the falling trend starts from 1957 and continues until 1974. The result is that the year 1992 is the beginning of a period of increasing temperature and climate change in Hamedan, and the temperature rise is 0.55 degrees averagely, 0.79 ° C at minimum temperature and 0.3 ° C at maximum temperature.
Ali Baratian; Zohreh Merianji
Volume 10, Issue 40 , February 2001, , Pages 61-64
Abstract
Evaporation is the process of change of water into steam in which water molecules leave the surface of water by receiving 600 Calories. This process can be carried out either from the surface of open water or soil or by plants. The amount of water that plants release into the atmosphere is called transpiration.The ...
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Evaporation is the process of change of water into steam in which water molecules leave the surface of water by receiving 600 Calories. This process can be carried out either from the surface of open water or soil or by plants. The amount of water that plants release into the atmosphere is called transpiration.The amount of evaporation from soil and plant surfaces cannot be separated, so the sum of the two is called evapotranspiration. The significance of evapotranspiration can be witnessed by considering the fact that 57% of the water which falls on lands all over the world is directly evaporated.The factors affecting evaporation are many, including: solar radiation, moisture content in nature, wind and its speed. The sun's radiation provides the energy needed for evaporation; hence during the day and in the summer there is more energy for evaporation due to more radiation, and evaporation is at its peak at this time.
The same is true about northern latitudes. The humidity or degree of air saturation is also effective in evaporation, as evaporation in dry air is more than humid air; furthermore, wind intensifies evaporation by removing the saturation layer and replacing dry air. Measurement of evapotranspiration in different regions is important in several respects: First, it controls the humidity of the region through evaporation, and therefore its measurement can be effective in determining the type of the region’s climate. Secondly, evaporation from the surface of rivers, lakes and various reservoirs causes water losses that need to be calculated. Thirdly, evapotranspiration from the vegetation within the basin area, which is also considered as water loss, is regarded as an important component of water cycle.
Fourthly, the amount of water used in irrigation schemes for agriculture and trees is also based on evapotranspiration, and determination of dimensions of irrigation networks is directly related to the amount and time of the loss of water entered into atmosphere through evapotranspiration. Since the province of Hamedan is considered as one of the agricultural regions of the country, it is necessary to study evapotranspiration and its amount in this province in order to estimate the actual needs of plant to water and also further the economic development of the region. Measurement of evapotranspiration is carried out in two ways: the direct method, which is measured by the lysimeter and evaporation pan, etc., and the second method, which is an experimental measurement in which practical formulas and equations are used to estimate the evapotranspiration rate.
