Mrs Fatemeh Vatanparast Galeh Juq, Dr Bromand Salahi, Batoul Zeinali,
Volume 0, Issue 0 (3-1921)
Abstract
In this research, the effect of two indicators OMI and RMM of Maden Julian fluctuation on the frequency of dust storms in Abadan, Ahvaz, Bostan, Bandar Mahshahr, Dezful, Ramhormoz and Masjed Soleyman located in Khuzestan province during six months (April to September) of the statistical period (1987 - 2021) was reviewed. Pearson's correlation coefficients between dust data and indicators were investigated and its results were calculated in the form of income zoning maps and the frequency percentage of each indicator for positive and negative phases. The results of the research findings indicate that there is a direct and significant relationship between the positive and negative phases of both indicators with dust, except for Dezful station in the positive phase of OMI and the negative phase of RMM and the highest correlation coefficient for Bandar Mahshahr and Dezful station is between -0.7-20.77 is in the positive phase of the RMM index. The relationship between the Madden Julian Oscillation and dust showed that between 51 and 59 percent of dust storms occurred in the negative phase of the OMI index and 40 to 49 percent in its positive phase. In the RMM index, 56 to 63 percent of dust storms occur in its negative phase and 37 to 50 percent in its positive phase. In fact, the negative phase of the RMM index has a higher percentage of dust storms than the negative phase of the OMI index. According to the results of the Monte Carlo test, the displacement of the positive and negative phases of the RMM index significantly leads to the occurrence of dust storms for most of the stations in Khuzestan province. Tracking the paths of dust entering Khuzestan province with the HYSPLIT model shows the movement of particles from Iraq, Arabia and the eastern parts of Syria towards the studied area.
Ph.d Elnaz Piroozi, Ph.d Sayyad Asghari Saraskanrood, Ph.d Batool Zeinali,
Volume 0, Issue 0 (3-1921)
Abstract
Landslides are among the most common and destructive natural hazards that change the shape of the earth's surface, and reviewing the damages caused by landslides, the need to investigate the factors influencing the occurrence of this phenomenon and predict its occurrence. proves that Khalkhal City, due to its special geological, climatic, and geomorphological characteristics and human activities, has been affected by the risk of landslides for a long time. Therefore, considering the importance of the issue; The purpose of this research is to produce a landslide risk map in this city. In this regard, first, the distribution map of landslides and influencing variables, including; DEM, slope, aspect, land use, lithology, distance from fault, distance from river, distance from road, and rainfall were provided. Next, after the fuzzy membership and determining the weight values of each factor using the CRITIC method, the landslide susceptibility map was prepared using the MARCOS multi-criteria decision-making method. The results of the study showed, respectively; that The factors of slope, land use, and lithology with weight coefficients of 0.148, 0.139, and 0.132 have the greatest influence on the occurrence of landslides in the region. According to the results of the research, respectively; 707.14 and 512.87 square kilometers of the area of the city are in high-risk and very high-risk categories, and these areas are areas that need management work and the implementation of protection projects. Also, considering the use of the ROC curve method the area under the curve (0.89), and the correlation of 0.83% between the final map obtained from the research and the distribution of sliding surfaces, the accuracy of the MARCOS method in identifying and zoning prone areas The risk of landslides in Khalkhal city is great.
Dr Batool Zeinali, Sima Khalili, Saideh Eiyni,
Volume 19, Issue 53 (7-2019)
Abstract
The aim of current research is atmospheric hazards climate zoning in Iran Northwest. So meteorological organization data were used in cases such as mean temperature , minimum temperature , maximum temperature, precipitation in monthly and daily scale for 13 synoptic stations in range of East Azerbaijan province, West Azerbaijan province) and Ardebil province during 26 years. (1990-2015) in this research , it was investigated 10 main atmospheric hazards such as famine or drought , hailstone,, heavy snow , thunder storm, severe precipitation, margin precipitation , blizzard , fogging , dust storm in range of Northwest bound. Then happening frequency maps were prepared with separating form for hazards by using Geographic information system. (GIS) Also spatial zoning maps were prepared for every class. Finally by combining all of hazards investigation; it was prepared Northwest region atmospheric hazards extensive map. Results show that, East, Southeast, center and West parts in Northwest region are located among most hazard zones based on happening frequency. But Northeast parts and zones have the least hazards. Also results express that blizzard and dust storm are main atmospheric hazards at Northwest regionThe highest hazard frequency in Northwest region relate to blizzard with 4148 hazards during 1990-2015 study period. The highest blizzard frequency in Ahar station is observed with 514 hazards. The second hazard in Northwest relate to dust phenomenon with 1948 cases. The highest frequency of mentioned case was observed in Maragheh station with 410 hazards. The third case in Northwest relate to thunder storm phenomenon with 1773 hazards. The sixth case relate to icing phenomenon with 1315 hazards meaning. The highest icing frequency is observed in Khalkhal station with 144 hazards. The seventh case relate to hailstone phenomenon at Northwest with 341 hazards. The highest of hailstone frequency is observed in Maragheh station with 56 hazards. The eighth case relate to fogging phenomenon with 333 hazards. The highest of fogging is observe in Ahar station with 135 hazards. The ninth case relate to famine or drought phenomenon at Northwest with 168 hazards. The highest of famine or drought frequency is observed in Urmia and Ardebil stations with 16 hazards totally. The highest margin precipitation is observed in Parsabad station with 19 hazards. The lowest frequency of margin precipitation relate to Makou and Khalkhal stations with 4 hazards totally.
