تحقیقات کاربردی علوم جغرافیایی

تحقیقات کاربردی علوم جغرافیایی

تحلیل چندنمایشی و رابطه چندمقیاسی بین بارش ماهانه عراق با پدیده ENSO (النینیو ـ نوسان جنوبی)

مقالات آماده انتشار
نویسندگان
نازک حسین اسد
داریوش یاراحمدی
حمید میرهاشمی
گروه جغرافیا، دانشکده ادبیات و علوم انسانی، دانشگاه لرستان، خرم آباد، ایران.
چکیده
پدیده ENSO به‌عنوان یکی از مهم‌ترین نوسان‌های بین‌سالانه در سیستم زمین ـ جو محسوب می‌شود که نقش قابل‌توجهی در تغییرات بارش مناطق مختلف جهان برعهده دارد. در این مطالعه به‌منظور شناسایی رابطه چندمقیاسی بین فازهای مختلف ENSO و تغییرات بارش ماهانه کشور عراق از شاخص ماهانه Niño3.4 و آنالیز موجک گسسته با بیشینه همپوشانی (MODWT) و آنالیز موجک پیوسته مورلت استفاده شد. به این ترتیب، نخست با تجزیه چندنمایشی سیگنال بارش ماهانه 16 ایستگاه واقع در عراق (1990-2020) تا شش (6) سطح فرکانسی (مقیاس زمانی ماهانه تا چندین ساله) مشخص شد که سیگنال بارش تمامی ایستگاه‌ها از الگوی رفتاری نسبتاً مشابه با دامنه نوسان‌های متفاوتی پیروی می‌کنند. بدین ترتیب که دامنه نوسان‌های بارش در مقیاس‌های زمانی ماهانه و فصلی برای ایستگاه‌های شمالی و کوهپایه‌ای (کرکوک، موصل و خانقین) شدیدتر از سایر مناطق عراق بوده که نشاندهنده فاصله کمتر بین ماه بارشی با ماه خشک در مناطق شمالی عراق است. همچنین روند کلی سیگنال A6 تمامی ایستگاه‌ها برای بازه زمانی 1995-2010 کاهشی بوده که شدت این روند در مناطق جنوبی و مرکزی عراق شدیدتر از منطقه شمالی است. نتایج تحلیل همبستگی و همبستگی موجکی چندمقیاسی نشان از رابطه مثبت و چندمقیاسی بین پدیده ENSO و بارش ماهانه عراق دارد که با کاربرد آزمون معناداری سوروگیت مشخص شد که این رابطه برای سطوح 1 تا 3 موجکی معنادار نیست و تنها برای مقیاس‌های زمانی 5/1 -3 سال و 5/2-5/5 سال (سطوح 4 و 5 موجکی) معنادار است. بنابراین بارش‌های عراق با رخداد ال‌نینیو یا فاز گرم ENSO، گرایش به افزایش و با رخداد لانینیا (فاز سرد)، گرایش به کاهش دارند.
کلیدواژه‌ها
بارش
النینیو
لانینیا
فرکانس
موجک

عنوان مقاله English

Multi-Resolution Analysis and Multiscale Relationship Between Monthly Precipitation in Iraq and the ENSO Phenomenon (El Niño–Southern Oscillation)

نویسندگان English

Nazok Hossein Asad
Dariush Yarahmadi
Hamid Mirhashemi
Department of Geographical, Faculty of Literature and Humanities, University of Lorestan, Khorramabad, Iran.
چکیده English

The ENSO phenomenon is considered one of the most important interannual oscillations in the Earth–atmosphere system and plays a significant role in precipitation variability across different regions of the world. In this study, to identify the multiscale relationship between different ENSO phases and monthly precipitation variability in Iraq, the monthly Niño3.4 index, the Maximum Overlap Discrete Wavelet Transform (MODWT), and the Continuous Morlet Wavelet Transform were employed. First, using multiresolution decomposition of the monthly precipitation signal from 16 stations across Iraq (1990-2020) into six (6) frequency levels (from monthly to multi-year scales), it was revealed that the precipitation signals at all stations follow a relatively similar pattern, although with different oscillation amplitudes. The amplitude of precipitation fluctuations at monthly and seasonal scales was found to be stronger at northern and foothill stations (Kirkuk, Mosul, and Khanaqin) compared to other regions of Iraq, indicating a shorter transition between wet and dry months in northern Iraq. Furthermore, the overall trend of the A6 component at all stations exhibited a decreasing pattern during 1995–2010, with this downward trend being more pronounced in the central and southern regions than in the north. The results of correlation analysis and multiscale wavelet coherence demonstrated a positive and multiscale relationship between ENSO and monthly precipitation in Iraq. Surrogate significance testing indicated that this relationship is not significant at wavelet levels 1 to 3 but becomes significant at 1.5–3-year and 2.5–5.5-year scales (wavelet levels 4 and 5). Overall, precipitation in Iraq tends to increase during El Niño (warm ENSO phase) events and decrease during La Niña (cold ENSO phase) events.

کلیدواژه‌ها English

Precipitation
El Niño
La Niña
Frequency
Wavelet
Addison, P. S. (2017). The illustrated wavelet transform handbook: introductory theory and applications in science, engineering, medicine and finance: CRC press.
Al-Khalidi, J., Dima, M., & Stefan, S. (2018). Large-scale modes impact on Iraq climate variability. Theoretical and Applied Climatology, 133(1), 179-190.
Al-Lami, A. M., Al-Timimi, Y. K., & Al-Salihi, A. M. (2024). Innovative trend analysis of annual rainfall in Iraq during 1980-2021. Journal of Agrometeorology, 26(2), 196-203.
Al-Lami, A. M., Al-Timimi, Y. K., & Al-Shamarti, H. K. (2021). Spatiotemporal analysis of some extreme rainfall indices over Iraq (1981–2017). Scientific Review Engineering and Environmental Sciences, 30(2), 221-235.
Aljuhaishi, S., Al-Timimi, Y., & Wahab, B. Spatio-temporal Variation of Weather Systems and their Seasonal Variability in Iraq.
Awadh, S. M. (2023). Impact of North African sand and dust storms on the Middle East using Iraq as an example: Causes, sources, and mitigation. Atmosphere, 14(1), 180.
Bharati, P., Deb, P., Hunt, K. M., Orr, A., & Dash, M. K. (2025). ENSO-induced latitudinal variation of the subtropical jet modulates extreme winter precipitation over the Western Himalaya. Advances in Atmospheric Sciences, 42(3), 427-437.
Bunde, A., Havlin, S., Koscielny-Bunde, E., & Schellnhuber, H.-J. (2001). Long term persistence in the atmosphere: global laws and tests of climate models. Physica A: Statistical Mechanics and its Applications, 302(1-4), 255-267.
Cai, W., Santoso, A., Collins, M., Dewitte, B., Karamperidou, C., Kug, J.-S., . . . Taschetto, A. S. (2021). Changing El Niño–Southern oscillation in a warming climate. Nature Reviews Earth & Environment, 2(9), 628-644.
Charney, J. G., & DeVore, J. G. (1979). Multiple flow equilibria in the atmosphere and blocking. Journal of the atmospheric sciences, 36(7), 1205-1216.
Di Carlo, E., Ruggieri, P., Davini, P., Tibaldi, S., & Corti, S. (2022). ENSO teleconnections and atmospheric mean state in idealised simulations. Climate Dynamics, 59(11), 3287-3304.
Eichner, J. F., Koscielny-Bunde, E., Bunde, A., Havlin, S., & Schellnhuber, H.-J. (2003). Power-law persistence and trends in the atmosphere: A detailed study of long temperature records. Physical Review E, 68(4), 046133.
Fadhel, S., & Han, D. (2025). On the connection between large-scale climate indices and rainfall variability in Iraq. Dynamics of Atmospheres and Oceans, 110, 101540.
Grimm, A. M., & Tedeschi, R. G. (2009). ENSO and extreme rainfall events in South America. Journal of Climate, 22(7), 1589-1609.
Grinsted, A., Moore, J. C., & Jevrejeva, S. (2004). Application of the cross wavelet transform and wavelet coherence to geophysical time series. Nonlinear processes in geophysics, 11(5/6), 561-566.
Jasim, A. I., & Awchi, T. A. (2020). Regional meteorological drought assessment in Iraq. Arabian Journal of Geosciences, 13(7), 284.
Jbianah, A., & Khalbas, M. I. (2022). Estimation of predictive potential of El Nino (La Nina) for long-term precipitation forecast in Iraq. Caspian Journal of Environmental Sciences, 20(4), 827-833.
Kadhum, J. H., Al-Zuhairi, M. F., & Hashim, A. A. (2022). Synoptic and dynamic analysis of few extreme rainfall events in Iraq. Modeling Earth Systems and Environment, 8(4), 4939-4952.
Kiflie, K. A., & Tao, L. (2020). Opposite effects of ENSO on the rainfall over the northern and equatorial Great Horn of Africa and possible causes. Advances in Meteorology, 2020(1), 9028523.
Kripalani, R., & Kumar, P. (2004). Northeast monsoon rainfall variability over south peninsular India vis‐à‐vis the Indian Ocean dipole mode. International Journal of Climatology: A Journal of the Royal Meteorological Society, 24(10), 1267-1282.
Kumar, P., & Foufoula‐Georgiou, E. (1997). Wavelet analysis for geophysical applications. Reviews of Geophysics, 35(4), 385-412.
Labat, D. (2008). Wavelet analysis of the annual discharge records of the world’s largest rivers. Advances in water resources, 31(1), 109-117.
Lark, R. M., & Webster, R. (2001). Changes in variance and correlation of soil properties with scale and location: analysis using an adapted maximal overlap discrete wavelet transform. European journal of soil science, 52(4), 547-562.
Lin, G., & Fu, Z. (2008). A universal model to characterize different multi-fractal behaviors of daily temperature records over China. Physica A: Statistical Mechanics and its Applications, 387(2-3), 573-579.
Lin, S., Dong, B., & Yang, S. (2024). Enhanced impacts of ENSO on the Southeast Asian summer monsoon under global warming and associated mechanisms. Geophysical Research Letters, 51(2), e2023GL106437.
Malinowski, J. C. (2002). Iraq: A Geography.
Martija-Díez, M., López-Parages, J., Rodríguez-Fonseca, B., & Losada, T. (2023). The stationarity of the ENSO teleconnection in European summer rainfall. Climate Dynamics, 61(1), 489-506.
McGregor, S., Gallant, A., & van Rensch, P. (2024). Quantifying ENSOs impact on Australia's regional monthly rainfall risk. Geophysical Research Letters, 51(6), e2023GL106298.
McPhaden, M. J., Zebiak, S. E., & Glantz, M. H. (2006). ENSO as an integrating concept in earth science. science, 314(5806), 1740-1745.
Mirhashemi, H. (2024). Analysis of multi-scale correlation and wavelet variance of time series of precipitation and flow of Khorramabad River. Iranian Journal of Watershed Management Science and Engineering, 18(64), 39-49.
Muslih, K. (2014). Identifying the climatic conditions in Iraq by tracking down cooling events.
Muslih, K. D., & Abbas, A. M. (2024). Climate of Iraq The Geography of Iraq (pp. 19-47): Springer.
Mutar, A. G., Abdulkareem, A. K., Hussain, H. H., Hassoon, A. F., & Rajab, J. M. (2023). The Impact of ENSO on the Precipitation in Iraq Regions. Paper presented at the IOP Conference Series: Earth and Environmental Science.
Mutar, A. G., Khtan, A., & George, L. E. (2021). Synoptic characteristics of torrential rains in southwest and southeast Iraq: A case study. Al-Mustansiriyah Journal of Science, 32(3), 1-7.
Nicholson, S. E. (2017). Climate and climatic variability of rainfall over eastern Africa. Reviews of Geophysics, 55(3), 590-635.
Orun, M., & Koçak, K. (2009). Applicatıon of detrended fluctuation analysis to temperature data from Turkey. International Journal of Climatology: A Journal of the Royal Meteorological Society, 29(14), 2130-2136.
Percival, D. B., & Walden, A. T. (2000). Wavelet methods for time series analysis (Vol. 4): Cambridge university press.
Philander, S. (1985). El niño and la niña. Journal of Atmospheric Sciences, 42(23), 2652-2662.
Rasmusson, E. M., & Carpenter, T. H. (1982). Variations in tropical sea surface temperature and surface wind fields associated with the Southern Oscillation/El Niño. Monthly weather review, 110(5), 354-384.
Robaa, E.-S. M., & Al-Barazanji, Z. (2015). Mann-Kendall trend analysis of surface air temperatures and rainfall in Iraq. Quarterly Journal of the Hungarian Meteorological Service, 119(4), 493-514.
Ropelewski, C. F., & Halpert, M. S. (1987). Global and regional scale precipitation patterns associated with the El Niño/Southern Oscillation. Monthly weather review, 115(8), 1606-1626.
Shaman, J. (2014). The seasonal effects of ENSO on European precipitation: Observational analysis. Journal of Climate, 27(17), 6423-6438.
Sun, X., Renard, B., Thyer, M., Westra, S., & Lang, M. (2015). A global analysis of the asymmetric effect of ENSO on extreme precipitation. Journal of Hydrology, 530, 51-65.
Timmermann, A., An, S.-I., Kug, J.-S., Jin, F.-F., Cai, W., Capotondi, A., . . . Stuecker, M. F. (2018). El Niño–southern oscillation complexity. Nature, 559(7715), 535-545.
Torrence, C., & Compo, G. P. (1998). A practical guide to wavelet analysis. Bulletin of the American Meteorological Society, 79(1), 61-78.
Trenberth, K. E. (1997). The definition of el nino. Bulletin of the American Meteorological Society, 78(12), 2771-2778.
Wang, C., Deser, C., Yu, J.-Y., DiNezio, P., & Clement, A. (2016). El Niño and southern oscillation (ENSO): a review. Coral reefs of the eastern tropical Pacific: Persistence and loss in a dynamic environment, 85-106.
Ya-Li, Y., Yan, D., Yan-Ling, W., Gang, H., & Yong-Sheng, Z. (2012). The interannual variations of summer precipitation in the northern Indian Ocean associated with ENSO. Atmospheric and Oceanic Science Letters, 5(4), 301-305.
Yun, K.-S., Timmermann, A., & Stuecker, M. F. (2020). Synchronized spatial shifts of Hadley and Walker circulations. Earth System Dynamics Discussions, 2020, 1-17.
Zhang, J., Hu, K., Huang, G., & Wang, Y. (2025). The upper-level atmospheric pathway of ENSO’s impact on winter rainfall in southern China. Geoscience Letters, 12(1), 26.
تحقیقات کاربردی علوم جغرافیایی

مقالات آماده انتشار، پذیرفته شده
انتشار آنلاین از 01 فروردین 1386