جستجوی مقالات مرتبط با کلیدواژه « میناب » در نشریات گروه « فیزیک »

Today, the existence of numerous sources of dust production is one of the environmental challenges of Hormozgan province. Remote sensing and using MODIS data is one of the effective methods for the detection and mapping of dust storms. At first, meteorological data of all synoptic stations in the study area were collected and analyzed. According to the results, the highest frequency of dust occurrence is related to the three months of July, August, and May, which are in spring and summer. October, December and November have the lowest occurrence of dust storms in the study area. Also, autumn with 12.5% has the lowest occurrence of dust storms in all stations in the study area, and spring with 34.4%, and then summer with 33.6% has been recorded as the highest occurrence of the dust storms. This research monitors and evaluates four detecting algorithms for identification of plume and dust source and dust storm emission in the Kostak- Bandar Abbas area in the Hormozgan Province using MODIS satellite data and the HYSPLIT model. Ackerman’s model, Normalized Difference Dust Index (NDDI), Thermal-infrared Dust Index (TDI), and thermal Infrared Integrated Dust Index (TIIDI) were four Algorithm methods for dust source and plume identification using MODIS Level 1B and MODIS Level 2 data. The results show that all of the algorithms except NDDI were successful in detecting dust plumes, but the most effective algorithm for plumes identification varied from event to event. In addition, TDI is the best algorithm comparing its results with those of other three algorithms. The results show that there are a lot of dust sources in the study area that have many negative effects on other populated areas in the Hormozgan province and its neighboring areas. The results indicate that the Flood Plains Deposits (Qal3), Natural Levee Deposits (Qal2), and Coastal Dunes (Qdune) play the most important role in dust production in the study area. The HYSPLIT (Hybrid Single-Particle Lagrangian Integrated Trajectory) model was used to trace wind flow backward and forward to the study area. The results of the HYSPLIT model show that the dust particles are mainly transported to the study area from three main paths, namely, Northeastern, the West, and the Southwestern part of the study area. The results also, show that dust plumes lifted and dispersed towards different directions including the north and northeast with 30%, the south with 25%, and the east with 20% of the total events in the study period 2000 to 2018. In addition, the results show that the study area has a high potential for the occurrence of dust storms during the year as many dust hotspots have been identified in this area. Also, the occurrence of more than a decade of drought, the presence of erosion-sensitive formations, and the presence of erosion-sensitive sedimentary units in the study area and its surrounding areas, especially in the seasonal wetland Jazmourian has provided conditions to aggravate this situation. Due to the economic and tourism importance of cities such as Bandar Abbas, Qeshm, and Minab, and especially the industrial and economic region west of Bandar Abbas and the existence of active dust sources around this region, the need for executive operations and watershed management activities is highly recommended.

Solar radiation, a renewable energy, is the most effective, economical and the safest source of energy which has the potential to be the major source of energy in near future. As a result optimum use of solar energy needs precise siting of solar site. The most accurate way of measuring solar radiation is using pyranometer which is not so popular around the world because of its high charge and lack of facilities. Therefore, nowadays the researchers use climatic and environmental parameters to estimate solar radiation (Belcher and DeGaetano, 2007: 10). Although meteorological parameters, namely relative humidity, cloudiness percentage, temperature and hours of sunshine affect the amount of earth received radiation, research has proved that hours of sunshine is the most effective factor on receiving radiation; it has been proved in the model of linear regression of Angstrom in the way of FAO- penman-Monteith method. Approximately 1445"> of Iran area, having 240-250 sunny days yearly is capable of producing a lot of solar energy. Angstrom model (1924) was made based on the relationship between received radiation and sunshine hours (Angstrom, 1924: 122). It was revised in 1940 (Prescott, 1940: 115). Sabziparvar (2008: 1002) believed that out of various studies, aiming at presenting a simple equation to estimate solar radiation in central arid region of Iran, Sabagh method has the least number of errors. This study aimed at finding the effect of climatic parameters, especially relative humidity on the amount of total received radiation between Minab and Bandarabas stations. In the present research daily data of synoptic meteorology stations of Minab and Bandarabas during the temporal period of 2006-2009 were studied in order to estimate not only the amount of received radiation but also the effect of relative humidity on radiation decrease in real standard mode. The aforesaid stations were chosen due to their similar features like the height difference less than 20m altitude, 4◦ latitude while different distance from the source of moist; Oman sea and Persian gulf. The amounts of solar radiation was estimated, using Bird and Hulstrom model, by considering both locative features (altitude, latitude and longitude) and climatic features (relative humidity, temperature, pressure, sunshine hours, sun height, atmosphere albedo, particle absorbing, earth albedo, atmosphere mass, ozone absorption and Rayleigh distribution). Moreover in order to estimate the effect of relative humidity on total received radiation decrease the values of climatic variables were supposed stable in standard mode. Finally daily and monthly values were presented as tables and graphs. Discussion and The findings of this study showed that the maximum amount of total received radiation of Minab station was in June, 14.48 MJ/m-2/ d-1, while for Bandarabas station was in May, 13.97 MJ/m-2/ d-1. In fact this difference during a month is due to the difference in the amount of relative humidity. In other words, high radiation of Bandarabas station in May is the result of both its less relative humidity than warm months and high solar height. As summer comes radiation decreases, for the amount of moist in atmosphere increases. The lowest amount of total received radiation of Bandarabas is in cold months in which slight angle of sun are the major reason for low received radiation. Besides total received radiation of Minab during winter is less than Bandarabas which is the result of more moist in June. Minab station received maximum amount of solar radiation coinciding with highest height of sun. In addition, sunshine hour decrease leads to minimum total received radiation during cold month. The most considerable point is total received radiation of Minab which is less than Bandarabas, for relative humidity of Minab is more than Bandarabas. Studying the effect of relative humidity on standard atmosphere showed that the amounts of total received radiation of the stations are not stable: it varies both in January form maximum amount, 6.4 MJ/ m-2/ d-1, with relative humidity of 10% to minimum amount, 5.6 MJ/ m-2/ d-1 with relative humidity of 90%, and in June from maximum amount, 18.4 MJ/m-2/ d-1 with relative humidity of 10% to minimum amount, 15.8 MJ/ m-2/ d-1, with relative humidity of 90%. As a matter of fact the amount of relative humidity in average mode has more effect on total received radiation compared with its low or high mode. Moreover it is necessary to say that the amount of total received radiation in different hours is 4 MJ/ m-2/ d-1, minimum, and 16 MJ/m-2/ d-1, maximum, considering the effect of relative humidity. Totally, it seems that Minab than BandarAbas station has more potential for energy production to Set Solar Sites because Minab station recive more radiation.