Iranian Journal of Geophysics

Iranian Journal of Geophysics

Investigating the effect of PV streamer on the activity of the Red Sea trough using the WRF model (case study)

Document Type : Research Article

Authors
Zakieh Alizadeh 1
Alireza Mohebalhojeh 2
Farhang Ahmadi-Givi 3
Sakineh Khansalari 4
1 Ph.D., Weather and Crisis Management Forecaster, General Department of Meteorology of Khuzestan Province, Ahvaz, Iran
2 Professor, Institute of Geophysics, University of Tehran, Tehran, Ira
3 Associate Professor, Institute of Geophysics, University of Tehran, Tehran, Ira
4 Assistant Professor, Atmospheric Science and Meteorological Research Center, Tehran, Iran
10.30499/ijg.2024.452237.1590
Abstract
The Middle East region, especially the eastern part of the Mediterranean Sea, is subject to rave events of heavy rains that lead to financial and human losses. These heavy rains can have various causes, one of which is the activation of the Red Sea Trough (RST). The Red Sea trough is an inverted low-pressure trough in the lower troposphere over Northeast Africa and the Red Sea. The main goal of the current research is to investigate the activity of the potential vorticity (PV) streamer caused by the Rossby-wave activity in the upper troposphere, its interaction with the circulation in the lower troposphere and the consequent effect on the activation of the RST and the occurrence of extreme precipitation events (EPE) in the region. The selection of these events is based on the information of the relevant websites and the results of valid researches. In the following, due to the important effect of the eastern Mediterranean Sea trough on the activity of the RST, the investigation of the PV streamer as an effective factor in wave breaking, receiving the moisture of the lower surfaces and the activity of RST will be carried out. This research uses ERA-Interim data and the WRF model to remove the PV anomaly in the upper and middle troposphere levels and investigate the meteorological quantities with and without the presence of the PV anomaly.
   In this way, the effect of the PV streamer and the eastern Mediterranean trough is discussed in the activation of RST in several extreme precipitation events in the region. In this study, two categories of EPE, which were caused by the activity of the Red Sea trough (ARST) or by factors other than ARST, were investigated. The results indicate that in most of the EPEs caused by ARST, the southward extension of the upper trough in the eastern Mediterranean Sea along with the PV streamer and the cold advection at the upper levels are present as the main conditions for the formation of EPE. However, there are also rare cases where the aforementioned trough extended southward in the middle level, but it was not accompanied by the Rossby wave breaking and the PV streamer at the upper level; the environmental conditions for the EPEs were provided only by the cold advection to the region at the lower levels by, for example, the westward exptension of the Siberian high pressure. However, in the systems in which RST was not active, the lower-level effects were dominant, and the role of the upper level was only in modifying the amount of moisture transfer to the region.
Keywords
Red sea trough
extreme precipitation events
potential vorticity streamer
eastern mediterranean trough
Rossby wave breaking

Subjects

پورآتشی، م. م. مرادی و ا. فتاحی (1396). شناسایی سامانه‌های کم‌فشار جنوبی. نشریه پژوهش‌های اقلیم‌شناسی، 31-32، 38-53.
خوش‌اخلاق، ف. ر. صفایی راد. و د. سلیمانی (1393). واکاوی همدیدی رخداد سیلاب آبان‌ماه 1390 در شهرستان‌های بهبهان و لیکک. پژوهش‌های جغرافیایی طبیعی 46، 4، 523-509.
عزیزی، ق. ف. خوش‌اخلاق. م. مولوی و ع. زندی (1395). نقش ضخامت لایه پایین وردسپهر بر روی بارش جغرافیا فصلنامه علمی-پژوهشی و بین-المللی انجمن جغرافیایی ایران 14، 48، 71-51.
قاضی‌پور، ش. ح. لشکری. و م. فرج‌زاده (1400). تحلیل روند شدت بارش سامانه‌های سودانی ورودی به ایران (مطالعه موردی: مسیرهای مستقل ورودی استان‌های خوزستان، بوشهر و هرمزگان). نشریه پژوهش‌های اقلیم‌شناسی، 47، 1-20.
لشکری، ح. (1375). الگوی سینوپتیکی بارش‌های شدید در جنوب غرب ایران. رساله دکتری جغرافیای طبیعی دانشگاه تربیت مدرس.
لشکری، ح. (1381). مسیریابی سامانه‌های کم‌فشار سودانی ورودی به ایران. ویژه نامه جغرافیا، 2، 133-156.
مرادی، م. (1386). بررسی نقش کم‌فشار گرمایی سودان-اتیوپی به ارتفاعات زاگرس در سامانه‌های مؤثر. رساله دکتری هواشناسی، دانشگاه آزاد اسلامی واحد علوم و تحقیقات.
مشکواتی، ا. ح.، و م. مرادی (1383). بررسی ناوه فشاری دریای سرخ از دیدگاه دینامیکی. نیوار، 52، 53-74.
نصیری، ب. (1378). تحلیل الگوی سینوپتیکی و دینامیکی بارش‌ها در حوضه‌های کرخه و دز. رساله دکتری جغرافیای طبیعی، دانشگاه تربیت مدرس.
Al-mazroui, M., S. Kamil, K. Ammar, K. Keay, and A. O. Alamoudi. (2016). Climatology of the 500-hPa Mediterranean storms associated with Saudi Arabia wet season precipitation. Clim. Dyn., 48, 3309–3324.
Al-Mutairi, M., H. A. Basset, M. Morsy, and A. Abdeldym. (2019). On the effect of Red Sea and topography on
     rainfall over Saudi Arabia: Case study. Atmos. Res., 10, 1–24.
Alpert, P., I. Osetinsky, B. Ziv, and H. Shafir. (2004a). Semi-objective classification for daily synoptic systems: Application to the Eastern Mediterranean climate change. Int. J. Climatol., 24, 1001–1011.
Awad, A. M., and M. Al-mazroui. (2016). Climatology of the winter Red Sea trough. Atmos. Res., 182, 20–29.
Dayan U., K. Nissen, and U. Ulbrich. (2015). Atmospheric conditions inducing extreme precipitation over the eastern and western Mediterranean. Nat. Hazards Earth Syst. Sci., 15, 2525–2544.
De Vries A. J., H. G. Ouwersloot, S. B. Feldstein, M. Riemer, A. M. El Kenawy, M. F. McCabe, and J. Lelieveld. (2018). Identification of tropical–extratropical interactions and extreme precipitation events in the Middle East based on potential vorticity and moisture transport. J. Geophys. Res., 123, 861–881.
De Vries A. J., S. B. Feldstein, M. Riemer, E. Tyrlis, M. Sprenger, M. Baumgart, M. Fnais, and J. Lelieveld. (2016). Dynamics of tropical–extratropical interactions and extreme precipitation events in Saudi Arabia in autumn, winter and spring. Q. J. Roy. Meteor. Soc., 142, 1862–1880.
De Vries, A. J. (2021). A global climatological perspective on the importance of Rossby wave breaking and intense moisture transport for extreme precipitation events. Wea. Clim. Dyn., 2, 129–161.
De Vries, A. J., E. Tyrlis, D. Edry, S. O. Krichak, B. Steil, and J. Lelieveld. (2013). Extreme precipitation events in the Middle East: Dynamics of the Active Red Sea Trough. J. Geophys. Res., 118, 7087–7108.
Dee, D., S. M. Uppala, A. J. Simmons, P. Berrisford, P. Poli, S. Kobayashi, U. Andrae, M. A. Balmaseda, G. Balsamo, P. Bauer, P. Bechtold, A. C. M. Beljaars, L. Van de Berg, J. Bidlot, N. Bormann, C. Delsol, R. Dragani, M. Fuentes, A. J. Geer, L. Haimberg. (2011). The ERA-Interim reanalysis: Configuration and performance of the data assimilation system. Q. J. R. Meteorol. Soc., 137, 553–597.
El-Fandy, M. G. (1946). Barometric lows of Cyprus. Quart. J. Roy. Meteor. Soc., 72, 291–306.
El-Fandy, M. G. (1948). The effect of Sudan monsoon low on the development of thundery conditions in Egypt, Palestine and Syria. Quart. J. Roy. Meteor. Soc., 74, 31–38.
El-Fandy, M. G. (1950a). Effects of topography and other factors on the movement of lows in the Middle East and Sudan. Bull. Amer. Meteor. Soc., 31, 375–381.
Favors, J. E., and J. T. Abatzoglou. (2013). Regional surges of monsoonal moisture into the southwestern United States. Mon. Wea. Rev., 141, 182–191.
Greenbaum, N., U. Schwartz, and N. Bergman (2010), Extreme floods and short-term hydroclimatological fluctuations in the hyper-arid Dead Sea region, Israel, Global Planet. Change, 70(1-4), 125–137, doi:10.1016/j. gloplacha.2009.11.013
Johnson, D. H. (1956). African synoptic meteorology; meteorology and the desert Locus. WMO. Tech. notes, 48–90.
Iranian Journal of Geophysics
Volume 19, Issue 1
March and April 2025
Pages 1-25