پژوهشهای دانش زمین

پژوهشهای دانش زمین

The role of the Arabian anticyclone core position in the spatial displacement of precipitation cores and moisture transport pathways of precipitating systems (Affecting southern Iran)

نوع مقاله : مقاله پژوهشی

نویسندگان
Ghasem Keikhosravi
Zinab Mohamadi
Department of Physical Geography, Faculty of Earth Sciences, Shahid Beheshti University, Tehran, Iran
10.48308/esrj.2026.107470
چکیده
The general structure of synoptic patterns in any region develops out of the interaction among several systems, among which one or two systems have more prominent roles compared to the others. In Western Asia, the Arabian subtropical Anticyclone (ASTAC) system has a determining role in the structure of the atmospheric patterns of the region. This research was conducted with the aim of investigating the role of this system in the spatial displacement of high-pressure cores and the track of precipitation systems in Iran. This study analyzed 40 strong precipitation systems in the southern part of Iran. First, the atmospheric data of these systems were extracted from the NCEP/NAR site for 48 h up to the end of the precipitation period across all troposphere levels. The high-pressure central core was extracted across all levels, and eventually, the cores of 700 hPa were chosen to locate the site of deployment of the cores. Then, the combined maps of the special stream and moisture, as well as the altitude maps for routing the system, humidity advection, and spatial displacement of Mediterranean trough at the levels of 850 and 700 HPa were chosen. The precipitation distribution map of each system was prepared, and the high-precipitation core was determined. Finally, the distance between the precipitation and high-pressure cores was measured. The findings indicated that the high-pressure cores of ASTAC were established in four general regions. The placement location of the cores determined the track of precipitation systems towards Iran and the precipitation zone of each system. In all cases, the humidity of systems was first advected through ASTAC cellular anticyclonic circulation over Sudan and Ethiopia (Sudan low). They were then advected through the southern streams of the Mediterranean trough over Arabia and Iran. The protraction and depth of troughs also had a close relationship with the location of ASTAC core establishment in a way that the high-pressure cores had a westward displacement. The same occurred for the axes of troughs and vice versa.
کلیدواژه‌ها
Arabian subtropical anticyclone
Iran
Low pressure Sudan
Moisture advection
Routing precipitation systems
موضوعات
Amini, M., Lashkari, H., Karampour, M. and Hojjati, Z., 2012. Synoptic analysis of systems with heavy rainfall and flooding in the Kashkan River basin for the statistical period (1350-1384). Journal of Geography and Planning, v. 17(43), p. 1-20 (In Persian).
Bell, G.D. and Bosart, L.F., 1989. A 15-year climatology of Northern Hemisphere 500 mb closed cyclone and anticyclone centers. Monthly Weather Review, v. 117(10), p. 2142-2164. https://doi.org/10.1175/1520-0493.
Darand, M. and Pazhoh, F., 2019. Synoptic analysis of sea level pressure patterns and Vertically Integrated Moisture Flux Convergence VIMFC during the occurrence of durable and pervasive rainfall in Iran, Dynamics of Atmospheres and Oceans, v. 86, ISSN 0377-0265, https://doi.org/10.1016/j.dynatmoce.2019.02.004.
Dayan, U. and Abramski, R., 1983. Heavy rain in the Middle East related to unusual jet stream properties, Bull Amer Meteor Soc 64: 1138-1140. https://doi.org/10.1175/1520-0477.
Enomoto, T., 2004. Interannual variability of the Bonin high associated with the propagation of Rossby waves along the Asian jet. Journal of the Meteorological Society of Japan Ser, v. 82(4), p. 1019-1034. https://doi.org/10.2151/jmsj.2004.1019.
Enomoto, T., Hoskins, B.J. and Matsuda, Y., 2003. The formation mechanism of the Bonin high in August. Quarterly Journal of the Royal Meteorological Society, v. 129(587), p. 157-178. https://doi.org/10.1256/qj.01.211.
Farajzadeh, M., Karimi Ahmadabad, M., Ghaemi, H. and Mobasheri, M.R., 2007. Studying the moisture flux over west of Iran: A case study of January 1 to 7, 1996 rain storm. Journal of Applied Sciences, v. 7, p. 3023-3030. https://doi.org 10.3923/jas.2007.3023.3030. (In Persian).
Ghaemi, E., Zarrin, A., Azadi, M. and Farajzadeh Asl, M., 2009. Analyzing the patterns of subtropical high pressure over Asia and Africa, Journal of Humanities, v. 1, p. 219-245 (In Persian).
Ghaemi, E., Zarrin, A., Azadi, M. and Farajzadeh Asl, M., 2009. Analyzing the patterns of subtropical high pressure over Asia and Africa, Journal of Humanities, v. 1, p. 219-245 (In Persian).
Hejazizadeh, Z., 1993. Evaluation of a subtropical high-pressure synoptic weather in Iran, Ph.D thesis, Tehran: Tarbiat Modares University (In Persian).
Izd Negahdar, Z., 1991. Synoptic study of some specific Mediterranean systems and their effects on Iran, Master's thesis in Meteorology, Institute of Geophysics, University of Tehran (In Persian).
Jafari, M. and Lashkari, H., 2023. Effect of Arabian subtropical high-pressure intensity on the ITCZ zonal displacement pattern in Northeast Africa. Theor Appl Climatol, v.  152, p. 135-149. https://doi.org/10.1007/s00704-023-04365-9.
Keikhosravi, G., Shakiba, A. and Hamidpour, P., 2022. Analysis of Synoptic and Thermodynamic Patterns Leading to extremely Heavy Rainfall and Estimation of Water Area Resulting from Precipitation in Karkheh Basin. Geographical Studies of Coastal Areas Journal, v. 3(8), p. 83-100. DOI:10.22124/gscaj.2022.20667.1108. (In Persian).
 Khoshakhlagh, F., Azizi, G. and Rahimi, M., 2011.Drought and wet weather patterns in southwest of Iran. Journal of Applied Geosciences Research, v. 12(25), p. 57-77. https://jgs.khu.ac.ir/article-1-652-fa.html. (In Persian).
Khosravi, Y., Dostkamian, M. and Taherian, E.M., 2017. Investigation and analysis of the moisture advection pattern of widespread precipitation in Iran, Scientific and Research Quarterly Journal of the Iranian Geographical Society, v. 15(53), p. 252. (In Persian).
Krichak, S.O. and Alpert, P., 1998. Role of large scale moist dynamics in November 1–5, 1994, hazardous Mediterranean weather. Journal of Geophysical Research Atmospheres, v. 103(16), p. 19453-19468. https://doi.org/10.1029/98JD01710.
Karimi, M., Jafari, M., Norouzi, F., Khoshakhlagh, F. and Shamsipour, A., 2022. Atmospheric circulation and precipitation in Southwest Asia: The role of the Arabian Anticyclone in precipitation of Iran, Journal of Atmospheric and Solar-Terrestrial Physics, v. 238-239, 2022, 105933, ISSN 1364-6826. https://doi.org/10.1016/j.jastp.2022.105933.
Karimi, M., Khoshakhlagh, F., Shamsi por, A.A. and Noruzi, F., 2019. Arabian subtropical High Pressure circulation patterns in the middle troposphere and its relationship with Iran's Precipitation. Journal of Geography and Planning, v. 23(69), p. 233-255 (In Persian).
Kumar, A., Dudhia, J., Rotunno, R., Niyogi, D. and Mohanty, U.C., 2008. Analysis of the 26 July 2005 heavy rain event over Mumbai, India using the Weather Research and Forecasting (WRF) model. Quarterly Journal of the Royal Meteorological Society, v. 134(636), p. 1897-1910. https://doi.org/10.1175/1520-0469 (1971)028<1342:TEWCDT>2.0.CO;2.
Lashkari, H., 1996.The synoptic pattern of intense precipitations in the south west of Iran. PhD Thesis. Faculty of Human Sciences, Tarbiat Modarres University, Tehran, Iran (In Persian).
Lashkari, H., Matkan, A.A., Azadi, M. and Mohammadi, Z., 2017.Synoptic analysis of the role of Saudi Arabia subtropical high pressure subtropical and polar jet streams and severe droughts in South and South West of Iran. Journal of Researches in Earth Sciences, v. 8(2), p. 141-163. https://www.sid.ir/Fa/Journal/ViewPaper.aspx?ID=298674. (In Persian).
Lashkari, H. and Mohammadi, Z ., 2015. The effect of the location of the Arabian subtropical high pressure on the precipitation systems in the south and southwest of Iran. Researches of Natural Geography, v. 47(1), p. 73-90. https://www.sid.ir. (In Persian).
Lashkari, H. and Mohammadi, Z., 2019.Study on the role of annual movements of Arabian subtropical high pressure in the late start of precipitation in southern and southwestern Iran. Theor Appl Climatol, v. 137, p. 2069-2076 (2019). https://doi.org/10.1007/s00704-018-2716-x.
Lavers, D. and Gabriele, V., 2013. The nexus between atmospheric rivers and extreme precipitation across Europe. Geophysical Research Letters. 40. 10.1002/grl.50636.
Lindesay, J.A. and Dabreton, P.C., 1993. Water vapor transport over southern Africa during wet and dry early and late summer months. In. j. climatology, v. 13, p. 151-170.
Mohammadi, Z. and Lashkari, H., 2018. Effects of Spatial Movement of Arabia Subtropical High Pressure and Subtropical Jet on Synoptic and Thermodynamic Patterns of Intense Wet Years in the South and South West Iran. Physical Geography Research, v. 50(3), p. 491-509. Doi: 10.22059/jphgr.2018.249422.1007165.
Mofidi, A. and Zarrin, A., 2005. Synoptic study of the effect of Sudanese low-pressure systems on the occurrence of torrential rains in Iran, Geographical Research, v. 113-136 (In Persian).
Parker, S.S., Hawes, J.T., Colucci, S.J. and Hayden, B.P., 1989. Climatology of 500 mb cyclones and anticyclones, 1950–85. Monthly weather review, v. 117(3), p. 558-571. https://doi.org/10.1175/1520-0493.
Rafiaei, A., Alijani, B. and Yazdani, R., 2014. Synoptic analysis of the beginning of premature precipitation prematurely in the cold season of Iran. Iranian Geophysical Journal, v. 8(3). http://www.magiran.com/view.asp?Type=pdf&ID=1348557&l=fa. (In Persian).
Saligheh, M. and Sadeghinia, M., 2010. Spatial variation of summer precipitation in the southern half of the subtropical high pressure Iran, Journal of Geography and Development, v. 17, p. 83-98 (In Persian).
Yin, M.T., 1994. Synoptic-aerologic study of the onset of the summer monsoon over India and Burma. Journal of Meteorology, v. 6(6), p. 393-400. https://doi.org/10.1175/1520-0469.
Yang, S., Webster, P. and Dong, M., 1992. Longitudinal heating gradient: Another possible factor influencing the intensity of the Asian Summer Monsoon Circulation, Advances in Atmospheric Sciences, v. 9(4), p. 397-410.
Zhang, Q., Wu, G. and Qian, Y., 2002. The bimodality of the 100 hPa South Asia High and its relationship to the climate anomaly over East Asia in summer. Journal of the Meteorological Society of Japan Ser, v. 80(4), p. 733-744. https://doi.org/10.2151/jmsj.80.733.