Mehrdad Hoseini; Naser Maleki; Farrokh Matlabifar
Volume 19, Issue 74 , August 2010, , Pages 86-90
Abstract
One of the basic and most fundamental factors in the structure of the planet is the climate. There is no doubt that humans, living things and manifestations of life on the Earth are affected by climatic conditions and atmospheric phenomena. Inappropriate distribution of dry land and water, different ...
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One of the basic and most fundamental factors in the structure of the planet is the climate. There is no doubt that humans, living things and manifestations of life on the Earth are affected by climatic conditions and atmospheric phenomena. Inappropriate distribution of dry land and water, different latitudes, passage of atmospheric systems, heights and elevations covered by snow and ice, dry desert without water and grass, forests covered by trees,... In different regions of the planet, has created different climatic conditions, in such a way that in the broad geography of the world, atmospheric and hydrological hazards such as floods, storms, thunder and lightning, fatal cold, overwhelming heat, etc., annihilate thousands of humans and living organisms annually, or bring about many financial and environmental losses. In this regard, today's civilized human is releasing into the atmosphere millions of tons of carbon dioxide and toxic pollutants annually in order to gain industrial agriculture, so that greenhouse gases have formed a dark blanket on the ozone layer, and this harsh and fatal contamination has seriously threatened the lives of humans and living beings. Therefore, today's violent climate and humans have caused climatic changes in micro and macro climatic levels. Therefore, it is desirable and imperative to identify and investigate climatic changes and to prepare research plans in order to overcome the hydrological atmospheric hazards and to reduce and control pollution and human industrial toxicants.
Mehrdad Hosseini; Abbas Shamsollahii
Volume 17, Issue 65 , May 2008, , Pages 28-29
Abstract
Flood forecasting and warning is one of the tasks that is in the first place of importance from the point of view of preserving life and the second place in terms of maintaining property. Flood is one of the natural disasters that occurs abruptly due to excessive precipitation in an area. The causes ...
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Flood forecasting and warning is one of the tasks that is in the first place of importance from the point of view of preserving life and the second place in terms of maintaining property. Flood is one of the natural disasters that occurs abruptly due to excessive precipitation in an area. The causes of flood can be attributed to physical and human factors. The mountainous nature of the country and the presence of numerous flood-prone areas, as well as the devastating floods of recent years and position of residential areas in the course of floods, indicate the magnitude and importance of the subject. Nowadays, the necessity of using modern methods and creating a center for flood forecasting and warning, and the use of radar and satellite information is seriously felt. To control flood and reduce its effects, measures such as improving buildings’ resistance, environmental control and construction of barriers are effective. This paper examines the simple definition of flood and the role of meteorology in prediction of floods and its methods.
Mehrdad Hosseini; Farrokh Matlabifar
Volume 16, Issue 63 , November 2007, , Pages 35-38
Abstract
Undoubtedly, floods are known as one of the most important natural disasters. In practice, the flood is considered to be the most enormous disaster in terms of mortality and financial losses. In a ten-year period in the world (1988-1988), about 390000 people were killed by natural disasters, 58% of which ...
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Undoubtedly, floods are known as one of the most important natural disasters. In practice, the flood is considered to be the most enormous disaster in terms of mortality and financial losses. In a ten-year period in the world (1988-1988), about 390000 people were killed by natural disasters, 58% of which were flood casualties, 26% related to earthquakes, and 16% were caused by storms and other disasters. The related financial losses in this short period were about $ 700 billion, 33% of which caused by flood, 29% by earthquake and 28% were related to the storm. Throughout history, humans have been attracted to the fertile lands that are located on the course of previous floods, and have made their lives easier by settling close to rich sources of water and food in these lands. The same river or water flow that provides people with livelihood will make them more vulnerable to flooding. Flood can be caused by heavy rainfall, accumulation of heavy and abnormal sediment behind dams or dams’ failure, rapid melting of snow, blockage of the course of rivers due to landslides, or explosions of water reservoirs.
Mehrdad Hosseini; Reza Borhani; Maryam Khattar
Volume 15, Issue 58 , August 2006, , Pages 22-27
Abstract
In this research, in order to investigate the frosts occurred at Ekbatan station (Hamedan), the minimum daily temperatures of this station were studied. In general, the frosts were divided into three weak (mild), moderate, and severe categories. Next, the range of changes in the time of occurrence of ...
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In this research, in order to investigate the frosts occurred at Ekbatan station (Hamedan), the minimum daily temperatures of this station were studied. In general, the frosts were divided into three weak (mild), moderate, and severe categories. Next, the range of changes in the time of occurrence of these frosts was determined and the frequency of their occurrence was calculated. It was also attempted to obtain an experimental formula for the first autumn frost in a particular year based on the date of the last frosts of the spring of that year, and to determine the probability of occurrence of temperature thresholds between 0 and -15 ° C in different months of year by calculating different statistical parameters. In addition, it has been tried by dividing the the year into 36 distinct decades (ten days) to calculate the temperatures that are possible to occur with different percentages of probability.
Mehrdad Hoseini
Volume 14, Issue 54 , August 2005, , Pages 32-35
Abstract
Precipitation is a climatic element that changes year by year, and in fact precipitation is a random variable over time. If long-term precipitation data are available, the probability of occurrence of precipitation can be determined by statistical methods. In this study, the city of Semnan has ...
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Precipitation is a climatic element that changes year by year, and in fact precipitation is a random variable over time. If long-term precipitation data are available, the probability of occurrence of precipitation can be determined by statistical methods. In this study, the city of Semnan has been selected in order to determine the probability of annual, seasonal and monthly precipitation. Precipitation data in this city have been analyzed using computer software and statistical methods. Wet and dry periods, seasonal and monthly variations in precipitation and the probability of occurrence of seasonal and monthly precipitation have been determined.
Mehrdad Hoseini
Volume 13, Issue 51 , November 2004, , Pages 15-17
Abstract
Climate change in Iran and the world is considered by most scientists to be due to the emergence of “greenhouse” state that will have adverse effects on the Planet from different viewpoints. Due to human interference in climate change, undeniable climate change has been asserted in various ...
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Climate change in Iran and the world is considered by most scientists to be due to the emergence of “greenhouse” state that will have adverse effects on the Planet from different viewpoints. Due to human interference in climate change, undeniable climate change has been asserted in various world reports and the latest statements by the International Community, but scientific doubts also exist on reasoning behind climate change reported by “CHANGEINTERGOVERNMENTALPANELONCLIMATE”. As BRYSON (1977) states, surge from one pattern to another might change the climate of some of the mid-range-latitude areas drastically, and it is very likely to create a “drought-or-flood” pattern. The increase in temperature in some of Iran's meteorological stations indicates a tendency towards arid climate, and probably the period of climate change has begun in the country of Iran. The country, according to the research, has a pattern of a number of years of droughts alternated by a number of rainy years. Environmental problems such as global warming, frequent occurrence of droughts, expansion of deserts and the increasing trend of desertification, increasing number of forbidden areas for the extraction of water and occurrence of destructive floods have caused ecological instability in the country and have increased the vulnerability of the country's natural resources.
Mehrdad Hoseini
Volume 12, Issue 48 , February 2003, , Pages 58-61
Abstract
Rainfall is a climatic element that changes year by year, and in fact rainfall is a random variable over time. If the long-term rainfall data are available, the probability of occurrence of precipitation can be determined by statistical methods.In this study, the city of Semnan has been selected in order ...
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Rainfall is a climatic element that changes year by year, and in fact rainfall is a random variable over time. If the long-term rainfall data are available, the probability of occurrence of precipitation can be determined by statistical methods.In this study, the city of Semnan has been selected in order to determine the probability of annual, seasonal and monthly precipitation. Precipitation data in this city have been analyzed using computer software and statistical methods. Wet and dry periods, seasonal and monthly variations in precipitation and the probability of occurrence of seasonal and monthly precipitation have been determined.
