پايش طوفان گردوغبار در نيمه غربي ايران مطالعه موردي: طوفان گردوغبار 16 تا 19 ژوئن 2015

Monitoring of Dust Storm in the Midwest of Iran Case Study: Dust Storm June 16-19, 2015

اين تحقيق باهدف شناسايي كانون و عوامل همديد موج طوفان گردوغبار 16 تا 19 ژوئن 2015 در غرب ايران انجام گرفت. جهت بررسي شرايط همديدي علل وقوع اين پديده، از مجموعه داده هاي پيش بيني ميان مدت جوي مركز اروپائي (ecmwf) باقدرت تفكيك 0/125درجه قوسي شامل، ارتفاع ژئوپتانسيل، امگا، فشار تراز دريا، مولفه هاي مداري و نصف النهاري، رطوبت ويژه، رطوبت خاك تا عمق 10 سانتي متري و عمق اپتيكي گردوغبار استفاده گرديد. جهت مسيريابي منشا ذرات گردوغبار مدل حداقل پارامترهاي هواشناسي (hysplit) مورد استفاده قرار گرفت. نتايج تحقيق نشان داد كه ناپايداري هاي ايجادشده توسط كم فشارهاي حرارتي سطح زمين و تحركات پرفشار عربستان، همراه با استقرار يك بريده كم فشار در سطوح مياني جو در شرق خزر در رخداد اين مخاطره موثر بوده است. بررسي نقشه هاي رديابي حاصل از hysplit نشان مي دهد كه دو مسير كلي براي انتقال گردوغبار به منطقه موردمطالعه قابل تشخيص است. 1 مسير شمال غربي جنوب شرقي در ارتفاع 1500 متري: كه با عبور از روي هسته هاي گردوغبار شكل گرفته در غرب عراق و شرق سوريه عمل انتقال به نيمه غربي ايران را انجام مي دهند؛ بطوريكه اين جريانات توانسته اند گردوغبار را تا جنوب غرب ايران نيز انتقال دهند.2 مسير غربي شرقي در ارتفاع 500 تا 1000 متري: منبع ذرات اين مسير داخل كشور (اطراف هورالعظيم) است كه منشا اصلي گردوغبار روزهاي 18 و 19 ژوئن در لرستان بوده است. با توجه به اينكه رطوبت خاك بيابان هاي عراق و سوريه تا عمق 10 سانتي متري كم تر از 15 درصد بوده است، با عبور جريانات از روي اين مناطق، ذرات ريز خاك به راحتي توسط سامانه هاي همديد به سمت غرب ايران منتقل شده است

This research was conducted to identify the dust storms in the Midwest of Iran from June 16 to 19, 2015. To investigate the synoptic conditions of the causes of this phenomenon, the ECMWF has an array of 0.125 degrees, including geopotential, omega, and sea level pressure, orbital and meridian components of the wind, specific humidity Soil moisture was applied to a depth of 10 cm. Similarly, for the purpose of routing the source of dust particles, the model of the Minimum Meteorological Parameters (HYSPLIT) Marv was used. The results of this study showed that in Lorestan province, non-ditches created by low-pressure thermal springs and high-altitude movements in Saudi Arabia caused the convergence and sucking of flows to the west of the country, as well as the establishment of a low-pressure cut at the middle levels of the atmosphere in the east of the Caspian. In the event of this risk, it has been effective. According to the average soil moisture from the surface of the earth to a depth of 10 cm in days with dust hazards, the moisture content of dust particles in the dust was less than 15%, due to the flow of streams from these fields without sufficient moisture, fine particles the soil is easily directed towards the study. A survey of Hysplit tracking maps shows that two general paths for the transfer of dust to the studied region can be detected. 1-Northwest - Southwest At an altitude of 1500 meters: passing through the dust nuclei formed in the northwest of Iraq and east of Syria, carry out the transfer of dust to the west-west of Iran. As these currents have been able to transfer dust to the southwest of Iran, this path can be considered the main route of dust dispersion to the region. 2- The western-eastern route at an altitude of 500 to 1000 meters: is the source of particles of this route inside the country (around Hurralazim) that entered the West of Iran and greatly reduced the horizontal visibility, which is the main source of dust on June 18 and 19. The investigation of the path of dust particles in the walnut shows that these particles were initially transferred to lower levels by low-pressure systems in the Midwest of Iran and then pulled in three directions on the ground.