Showing 3 results for Greenhouse Gases
, , ,
Volume 19, Issue 52 (3-2019)
Abstract
The heat waves today are one of the most important climatic hazards in the world. According to many scientists, the Severe and frequent occurrence of heat waves in recent years has been due to the emission of greenhouse gases and consequent increased global warming. The purpose of this study is to investigate changes in the frequency and intensity of heat waves As well as their relationship with Global land-ocean temperature anomalies and greenhouse gases in the north-west of Iran. At First, maximum temperature of two meters of the surface during the period from 1851 to 2014 for 164 years was obtained from NASA’s website, then the maps of heat waves was drawn and extracted. Then, we analyzed and evaluated the frequency and severity of the heat waves, as well as changes in the annual, decade, fifty years old fluctuations and their centenary were analyzed. To achieve the research objectives, Pearson and Spearman correlation methods, linear and polynomial regression and non-parametric Mann-Kendall test were used. The results showed that the frequency of occurrence of heat waves in the considered period interval is incremental and relevant, and the most frequency of occurrence was in decades. Also the intensity of the heat waves is associated with a relatively significant increase, and the most intense heat waves occurred in the decades of the late 20th and early 21st century until the present period. The results of the correlation coefficients indicated that the intensity and frequency of the heat wave incidence have a positive and significant correlation with the Global land-ocean temperature anomalies. The results of investigating the relationship between frequency and intensity of heat waves with 4 important greenhouse gases, including: (CO2, CH4, N2O, SF6), showed that, except for the positive and significant correlation of carbon dioxide gas with the most severe heat waves in June, There was no meaningful relationship between them. The results of the Mann-Kendall test indicate an incremental and significant increase in the frequency and intensity of heat wave events in the North-West region of Iran.
Dr Mohamad Zaheri, Mr Ali Majnouni-Toutakhane,
Volume 19, Issue 53 (6-2019)
Abstract
The increased use of thermal power plants has led to the spread of greenhouse gases in the air and has caused psychological problems for humans. Accordingly, the present study was conducted to measure the pollutants released by Sahand Bonab thermal power plant and to investigate the effects of this pollution on the psychological and psychological pressure of rural residents. The GWP100 method was used to measure the pollutants of the power plant and to measure the mental and emotional pressures of the citizens, a questionnaire was used to assess the psychological stress of Markham. The statistical population of this study is 10254 people over 15 years of age in 7 villages located in the greenhouse of the power plant. Using formulas and simple random sampling, 375 subjects were selected as sample size. The results showed that the most pollutants released are CO2 and NOx, which is 4.17 times the warm seasons in the seasons. Also, analysis of the results by using a Pearson test showed that six variables including neurological and disturbing variables p= 0.272, stress and psychological stress p= 0.325, feeling of energy decrease, p= 0.287, feeling of despair and disappointment in life p = 0.142, feeling Depression in life of p= 0.211 and change in behavior patterns in everyday life p= 0.269 had the most effect on air pollution. Also, mental and psychological stress in nearby villages was higher than in remote villages, more women than young men than older men and elderly people. The results of multivariate regression and path analysis showed that in general, the air pollution caused by the power plant has the ability to explain R2 = 37.42 percent of the changes related to the psychological and psychological pressure of the villagers. Finally, it can be said that thermal power plants have negative mental and psychological effects according to type of activity, type of age and gender of the villagers, which should be considered in the studies of the construction of power plants.
Mojtaba Shahnazari, Zahra Hejazizadeh, Mohammad Saligheh,
Volume 20, Issue 59 (12-2020)
Abstract
Abstract
In this research, while studying climate conditions in the current period and analyzing changes in temperature, precipitation level, and the sunlight received, current conditions were also analyzed based on daily data from synoptic stations in the region, which had meteorological data recorded for at least 30 years. Given the environmental conditions necessary for the growth of rice, the availability of its phenological data, its high-low temperature thresholds, the Degree Day systems needed for the completion of its life cycle, and the phenological processes related to its economic production, a suitable agricultural calendar was specified. During the March-July period, this calendar showed variations in different provinces. Based on the current temperature conditions and the probable continued warming trend of the planet in the decades to come, nwoDscale was applied to the output from the atmospheric general circulation model MCdaH3 under scenario using LARS-WG5 model. In this study, years between 1969 and 1990 were used as the base period, while years between 2046 and 2065 were studied as the future period. Temperature and precipitation conditions for the future period were simulated. Obtained output was then studied and compared with temperature conditions that were suitable for the plant to grow in the region. With some differences, results showed that the agricultural calendar for rice in Gilan and Mazandaran provinces will shift to winter. Given the different temperature conditions of Golestan province, its agricultural calendar will shift to spring.
