Investigating the Atmospheric Structure of the Von Phenomenon at the Time of Forest Fires in Northern Iran

Document Type : Research Article

Authors

• Faramarz Khoshakhlagh ¹
• Hasan Haji Mohammadi ²
• Hosein Koshky ³

¹ Associate Professor in Natural Geography,University of Tehran, Tehran, Iran

² PhD Candidate in Climatology,Tarbiat Modares University , Tehran, Iran

³ PhD Candidate in Climatology, University of Tehran, Tehran, Iran

10.22067/geoeh.2022.76403.1219

Abstract

In order to investigate the atmospheric mechanisms governing the occurrence of the Von phenomenon at the time of forest fires in northern Iran, four types of data were used in the research. So, changes in parameters such as temperature, pressure and wind were investigated. Networked data from the National Environmental Prediction / Atmospheric Science Centers (NCEP/NCAR) and the European Center for Medium-Term Atmospheric Prediction (ECMWF) were then used to explain the structure of the atmosphere. Modis sensor images were used to study the surface temperature of the earth and suspended airborne particle model was used to track air masses. It was found that during the studied period, the event of January 25-31, 2007 was one of the strongest and most pervasive phones that occured in the region. The results showed that by forming a high pressure cell located in the south of the country and a low pressure cell in the wind protection part of Alborz mountain, it has created a strong pressure gradient and caused the south current to affect the northern regions of Iran. Accordingly, during a static-dynamic process, a wind turbine rotational current has been formed in the Alborz mountain range wind turbine. Moreover, by the ascent of the air mass on the Alborz mountain range, its moisture discharge, the passage of the air over the mountain, and its flow in the region and the heatless heat, the hot and dry air mass entered the region which had been accompanied by strong winds affecting fire-prone areas. With an increase in wind speed and a positive temperature drop, a sudden jump and increase in temperature had taken place. Trackings also showed that the main source of flow entering the region is in the northern part of the Persian Gulf and northeastern Africa.

Keywords

• Wind Phone
• Fire
• Pressure Gradient
• Northern Iran
• Synoptic

Main Subjects

• Climatic and atmospheric hazards

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©2024 The author(s). This is an open access article distributed under Creative Commons Attribution 4.0 International License (CC BY 4.0)

References

- پرنیان، علی؛ 1387. شرایط ایجاد فون بر روی استان‌های گیلان و مازندران، پایان‌نامه کارشناسی ارشد، استاد راهنما: صفاییان، پرویز، دانشگاه آزاد اسلامی واحد تهران شمال، دانشکده علوم و فنون دریایی، گروه فیزیک.

- جهانبخش، اسدی، حاجی محمدی، حسن؛ 1399. بررسی الگوهای همدیدی آتش‌سوزی جنگل (مطالعه موردی: جنگل‌های استان گلستان). فضای جغرافیایی، 20(70), 19-35.

 http://geographical-space.iau-ahar.ac.ir/article-1-2704-fa.html

- حاجی محمدی، حسن، باعقیده، محمد، فلاح قالهری، غلامعباس؛ 1396. بررسی ساختار جو در زمان رخداد آتش‌سوزی در شمال ایران. مجله آمایش جغرافیایی فضا. (25)7، 187-206.

https://gps.gu.ac.ir/article_54249.html  

- حسن پور چماچایی، رضا؛ 1385. بررسی سینوپتیکی باد گرم و اثر آن بر روی آتش‌سوزی در عرصه‌های جنگلی استان گیلان، پایان نامه کارشناسی ارشد. استاد راهنما: رضایی، پرویز، دانشگاه آزاد اسلامی واحد رشت. گروه جغرافیا.

- رنجبر سعادت آبادی، عباس، پورمیرزا، جمیله؛ 1394. مطالعه‌ هواشناختی پدیده‌ گرمباد در استان گیلان. فصلنامه جغرافیا و توسعه، 13(40)، 69-90.                                       https://doi.org/10.22111/gdij.2015.2099

- شیرزادی، هما؛ 1371. بررسی اوضاع سینوپتیکی و فیزیکی پدیده فون و اثرات مخرب آن در ایران، پایان نامه کارشناسی ارشد. استاد راهنما: قائمی، هوشنگ، دانشگاه تهران، مؤسسه‌ ژئوفیزیک، گروه هواشناسی.

- عزیزی قاسم، یوسفی یداله (1388. گرمباد (باد فون) و آتش‌سوزی جنگل در استان‌های مازندران و گیلان (نمونه: آتش‌سوزی تاریخ 25-30 آذر 1384)، فصلنامه تحقیقات جغرافیایی. شماره 92. 15407- 15434.

 https://www.sid.ir/fa/VEWSSID/J_pdf/55313889201.pdf

 

- De Wekker, S. F., & Snyder, B. J., 2013. Mountain weather research and forecasting: recent progress and current challenges (Vol. 750). F. K. Chow (Ed.). Dordrecht, The Netherlands: Springer. https://link.springer.com/book/10.1007/978-94-007-4098-3.

- Drobinski, P., Haeberli, C., Richard, E., Lothon, M., Dabas, A. M., Flamant, P. H & Steinacker, R., 2003. Scale interaction processes during the MAP IOP 12 south föhn event in the Rhine Valley.https://doi.org/10.1256/qj.02.35.

- Quarterly Journal of the Royal Meteorological Society: A journal of the atmospheric sciences, applied meteorology and physical oceanography, 129(588), 729-753.https://doi.org/10.1256/qj.02.42.

- Gaffin, D. M., 2002. Unexpected warming induced by foehn winds in the lee of the Smoky Mountains. Weather and forecasting,17(4),907-915. https://doi.org/10.1175/1520-0434(2002)017%3C0907:UWIBFW%3E2.0.CO;2.

- Ghavidel, Y., Farajzadeh, M., & Khaleghi Babaei, M., 2016. Synoptic backgrounds of the widest wildfire in Mazandaran Province of Iran during December 11–13, 2010. Meteorology and Atmospheric Physics, 128(6), 763-777. https://link.springer.com/article/10.1007/s00703-016-443-3.

- Grosvenor, D. P., King, J. C., Choularton, T. W., & Lachlan-Cope, T., 2014. Downslope föhn winds over the Antarctic Peninsula and their effect on the Larsen ice shelves. Atmospheric Chemistry and Physics, 14(18), 9481-9509. https://doi.org/10.5194/acp-14-9481-2014.

- Keeley, J. E., 2004. Impact of antecedent climate on fire regimes in coastal California. International Journal of Wildland Fire, 13(2), 173-182. https://www.publish.csiro.au/wf/WF03037.

- Klemp, J. B., & Lilly, D. R., 1975. The dynamics of wave-induced downslope winds. Journal of Atmospheric Sciences, 32(2), 320-339.

https://doi.org/10.1175/1520-0469(1975)032%3C0320:TDOWID%3E2.0.CO;2.

- McGowan, H. A., & Sturman, A. P., 1996. Regional and local scale characteristics of foehn wind events over the South Island of New Zealand. Meteorology and Atmospheric Physics, 58(1), 151-164. https://doi.org/10.1007/BF01027562.

- Mofidi, A., Soltanzadeh, I., Yousefi, Y., Zarrin, A., Soltani, M., Masoompour Samakosh, J., & Miller, S. T., 2015. Modeling the exceptional south Foehn event (Garmij) over the Alborz Mountains during the extreme forest fire of December 2005. Natural Hazards, 75(3), 2489-2518. https://doi.org/10.1007/s11069-014-1440-9.

- Richner, H. and Th. Gutermann., 2007. Statistical analysis of foehn in Altdorf, Switzerland. Extended Abstracts Volume 2, Int. Conf. Alpine Meteorol., June 4 to 8, 2007, Chambéry, France, 457-460.

https://www.researchgate.net/profile/HansRichner/publication/266889652_Statistical_analysisof_foehn_in_Altdorf_Switzerland/links/547330b70cf24bc8ea19c891/Statistical-analysis-of foehn-in-Altdorf-Switzerland.pdf.

- Speirs, J. C., Steinhoff, D. F., McGowan, H. A., Bromwich, D. H., & Monaghan, A. J., 2010. Foehn winds in the McMurdo Dry Valleys, Antarctica: The origin of extreme warming events. Journal of Climate, 23(13), 3577-3598. https://doi.org/10.1175/2010JCLI3382.1.