Temporal Structure and Episode Characteristics of Atmospheric Stagnation in Balıkesir (2000–2024)

Abstract

Atmospheric stagnation is a meteorological phenomenon characterized by low wind speeds and weak atmospheric dispersion conditions, promoting air pollutant accumulation and influencing local climate processes. This study investigates the long-term characteristics of atmospheric stagnation over Balıkesir in the South Marmara Region of Türkiye using hourly meteorological observations for 2000–2024. Atmospheric stagnation was identified using a wind speed threshold-based approach at hourly, daily, and episode scales, without applying any gap-filling procedure. Stagnation episodes were defined as periods lasting at least one day and consisting of consecutive stagnation days. Stagnation hours, stagnation days, and multi-day stagnation episodes were identified, and their temporal trends were evaluated using the non-parametric Mann–Kendall test and Sen's slope estimator. In addition, the diurnal variation of stagnation conditions was examined. Approximately 48% of the valid hourly observations and 45% of the analyzed days were classified as stagnation conditions. No statistically significant long-term trends were detected in annual stagnation hours or stagnation days, whereas stagnation episode frequency showed a significant increasing trend. No significant trend was observed in episode duration. Diurnal analysis indicated that stagnation conditions occurred predominantly during nighttime and early morning hours. These findings suggest that the temporal structure and organization of atmospheric stagnation have changed over time, despite little variation in its overall duration.

Keywords

• Atmospheric stagnation
• Temporal structure
• Stagnation episodes
• Wind speed
• Balıkesir

Supporting Institution

We would like to express our sincere gratitude to the Scientific Research Projects Unit of Balıkesir University for their valuable contributions to the realization of this study.

Project Number

Balıkesir Üniversitesi Bilimsel Araştırma Projeleri Birimi. Proje No: 2025/146

Ethical Statement

Ethical approval is not required for this study.

Thanks

We would also like to thank the Balıkesir Regional Directorate of Meteorology for their valuable collaboration and contributions to the completion of this study.

BALIKESİR’DE ATMOSFERİK DURGUNLUĞUN ZAMANSAL YAPISI VE EPİZOT ÖZELLİKLERİ (2000–2024)

Abstract

Atmosferik durgunluk, düşük rüzgâr hızları ve zayıf atmosferik dağılım koşulları ile karakterize edilen, hava kirliliği birikimi ve yerel iklim süreçleri üzerinde önemli etkilere sahip bir meteorolojik olgudur. Bu çalışmada, Türkiye’nin Güney Marmara Bölgesi’nde yer alan Balıkesir ili için 2000–2024 dönemini kapsayan saatlik meteorolojik gözlemler kullanılarak atmosferik durgunluk koşullarının uzun dönemli özellikleri incelenmiştir. Atmosferik durgunluk, rüzgâr hızı temelli bir eşik yaklaşımı kullanılarak saatlik, günlük ve epizot ölçeklerinde tanımlanmış; analizler herhangi bir veri doldurma işlemi uygulanmadan gerçekleştirilmiştir. Durgunluk epizotları, en az bir gün süreyle devam eden ve ardışık durgun günlerin birleşimi olarak tanımlanmıştır. Durgun saatler, durgun günler ve çok günlük durgunluk epizotları belirlenmiş; bu göstergelerin zamansal eğilimleri parametrik olmayan Mann–Kendall testi ve Sen’in eğim kestiricisi ile değerlendirilmiştir. Ayrıca, durgunluk koşullarının gün içindeki dağılımı analiz edilmiştir. Sonuçlar, Balıkesir’de geçerli saatlerin yaklaşık %48’inin durgun saat, günlerin ise yaklaşık %45’inin durgun gün olarak sınıflandırıldığını göstermektedir. Yıllık toplam durgun saat ve durgun gün sayılarında anlamlı bir uzun dönemli eğilim tespit edilmezken, durgunluk epizotlarının sayısında istatistiksel olarak anlamlı bir artış belirlenmiştir. Epizot sürelerinde ise anlamlı bir değişim gözlenmemiştir. Gün içi analizler, durgunluk koşullarının gece ve erken sabah saatlerinde yoğunlaştığını ortaya koymaktadır. Bu bulgular, atmosferik durgunluğun toplam süresinden ziyade zamansal yapısında ve organizasyonunda değişimler yaşandığını göstermektedir.

Keywords

• Atmosferik durgunluk
• Zamansal yapı
• Durgunluk epizotları
• Rüzgâr hızı
• Balıkesir

Supporting Institution

Bu çalışmanın gerçekleşmesinde değerli katkılarından dolayı Balıkesir Üniversitesi Bilimsel Araştırma Projeleri Birimine teşekkürlerimizi sunarız.

Project Number

Balıkesir Üniversitesi Bilimsel Araştırma Projeleri Birimi. Proje No: 2025/146

Ethical Statement

Bu çalışma için etik kurul onayına gerek yoktur.

Thanks

Bu çalışmanın gerçekleşmesinde değerli işbirliği ve katkılarından dolayı Balıkesir İl Meteoroloji Bölge müdürülüğüne teşekkürlerimzi sunarız.

References

1. Chen, Z., Xie, X., Cai, J., Chen, D., Gao, B., He, B., Cheng, N., ve Xu, B. (2018) Understanding meteorological influences on PM 2.5 concentrations across China: a temporal and spatial perspective, Atmospheric Chemistry and Physics, 18(8), 5343-5358. https://doi.org/10.5194/acp-18-5343-2018
2. Dawson, J. P., Bloomer, B. J., Winner, D. A., ve Weaver, C. P. (2014) Understanding the meteorological drivers of US particulate matter concentrations in a changing climate, Bulletin of the American Meteorological Society, 95(4), 521-532. https://doi.org/10.1175/BAMS-D-12-00181.1
3. Gao, Y., Zhang, L., Zhang, G., Yan, F., Zhang, S., Sheng, L., Li, J., Wang, M., Wu, S., ve Fu, J. S. (2020) The climate impact on atmospheric stagnation and capability of stagnation indices in elucidating the haze events over North China Plain and Northeast China, Chemosphere, 258, 127335. https://doi.org/10.1016/j.chemosphere.2020.127335
4. Garrido-Perez, J. M., Ordóñez, C., Barriopedro, D., García-Herrera, R., Schnell, J. L., ve Horton, D. E. (2021) A storyline view of the projected role of remote drivers on summer air stagnation in Europe and the United States, Environmental Research Letters, 17(1), 014026. https://doi.org/10.1088/1748-9326/ac4290
5. Garrido-Perez, J. M., Ordóñez, C., García-Herrera, R., ve Barriopedro, D. (2018) Air stagnation in Europe: spatiotemporal variability and impact on air quality, Science of The Total Environment, 645, 1238-1252. https://doi.org/10.1016/j.scitotenv.2018.07.238
6. Gutiérrez, C., Molina, M., Ortega, M., Lopez-Franca, N., ve Sánchez, E. (2024) Low-wind climatology (1979–2018) over Europe from ERA5 reanalysis, Climate Dynamics, 62(5), 4155-4170.
7. Horton, D. E., ve Diffenbaugh, N. S. (2012) Response of air stagnation frequency to anthropogenically enhanced radiative forcing, Environmental Research Letters, 7(4), 044034. https://doi.org/10.1088/1748-9326/7/4/044034
8. Horton, D. E., Skinner, C. B., Singh, D., ve Diffenbaugh, N. S. (2014) Occurrence and persistence of future atmospheric stagnation events, Nature Climate Change, 4(8), 698-703. https://doi.org/10.1038/nclimate2272

9. Hou, P., ve Wu, S. (2016) Long-term changes in extreme air pollution meteorology and the implications for air quality, Scientific Reports, 6(1), 23792. https://doi.org/10.1038/srep23792
10. Hu, A., Xie, X., Gong, K., Hou, Y., Zhao, Z., ve Hu, J. (2022) Assessing the Impacts of Climate Change on Meteorology and Air Stagnation in China Using a Dynamical Downscaling Method, Frontiers in Environmental Science, 10, 894887. https://doi.org/10.3389/fenvs.2022.894887
11. Huang, Q., Cai, X., Song, Y., ve Zhu, T. (2017) Air stagnation in China (1985–2014): climatological mean features and trends, Atmospheric Chemistry and Physics, 17(12), 7793-7805. https://doi.org/10.5194/acp-17-7793-2017
12. Kampa, M., ve Castanas, E. (2008) Human health effects of air pollution, Environmental pollution, 151(2), 362-367. https://doi.org/10.1016/j.envpol.2007.06.012
13. Lee, D., Wang, S.-Y. S., Zhao, L., Kim, H. C., Kim, K., ve Yoon, J.-H. (2020) Long-term increase in atmospheric stagnant conditions over northeast Asia and the role of greenhouse gases-driven warming, Atmospheric Environment, 241, 117772. https://doi.org/10.1016/j.atmosenv.2020.117772
14. Leibensperger, E. M., Mickley, L. J., ve Jacob, D. J. (2008) Sensitivity of US air quality to mid-latitude cyclone frequency and implications of 1980–2006 climate change, Atmospheric Chemistry and Physics, 8(23), 7075-7086. https://doi.org/10.5194/acp-8-7075-2008
15. Liang, Q., Miao, Y., Yan, Y., ve Liu, S. (2025) Winter PM2. 5 pollution in china's largest arid urban agglomeration: Impacts of basin terrain and synoptic-scale circulations, Atmospheric Research, 108728. https://doi.org/10.1016/j.atmosres.2025.108728
16. Liao, T., Gui, K., Jiang, W., Wang, S., Wang, B., Zeng, Z., Che, H., Wang, Y., ve Sun, Y. (2018) Air stagnation and its impact on air quality during winter in Sichuan and Chongqing, southwestern China, Science of the Total Environment, 635, 576-585. https://doi.org/10.1016/j.scitotenv.2018.04.122
17. Maddison, J. W., Abalos, M., Barriopedro, D., García-Herrera, R., Garrido-Perez, J. M., ve Ordóñez, C. (2021) Linking air stagnation in Europe with the synoptic-to large-scale atmospheric circulation, Weather and Climate Dynamics, 2(3), 675-694. https://doi.org/10.5194/wcd-2-675-2021
18. Maddison, J. W., Abalos, M., Barriopedro, D., García-Herrera, R., Garrido-Perez, J. M., Ordóñez, C., ve Simpson, I. R. (2023) Assessing the projected changes in European air stagnation due to climate change, Journal of Climate, 36(3), 917-930. https://doi.org/10.1175/JCLI-D-22-0180.1
19. MGM. (2024). Türkiye Cumhuriyeti Çevre, Şehircilik ve İklim Değişikliği Bakanlığı, Meteoloroloji Genel Müdürlüğü. https://www.mgm.gov.tr. (Erişim Tarihi: 23.03.2026)
20. MGM. (2025). Türkiye Cumhuriyeti Çevre, Şehircilik ve İklim Değişikliği Bakanlığı, Meteoloroloji Genel Müdürlüğü. MGM. https://mgm.gov.tr. (Erişim Tarihi: 23.09.2025)
21. Schnell, J., Prather, M., Josse, B., Naik, V., Horowitz, L., Cameron-Smith, P., Bergmann, D., Zeng, G., Plummer, D., ve Sudo, K. (2015) Use of North American and European air quality networks to evaluate global chemistry–climate modeling of surface ozone, Atmospheric Chemistry and Physics, 15(18), 10581-10596. https://doi.org/10.5194/acp-15-10581-2015
22. Sekula, P., Ustrnul, Z., Bokwa, A., Bochenek, B., ve Zimnoch, M. (2022) Random forests assessment of the role of atmospheric circulation in PM10 in an urban area with complex topography, Sustainability, 14(6), 3388. https://doi.org/10.3390/su14063388
23. Tai, A. P., Mickley, L. J., ve Jacob, D. J. (2010) Correlations between fine particulate matter (PM2. 5) and meteorological variables in the United States: Implications for the sensitivity of PM2. 5 to climate change, Atmospheric environment, 44(32), 3976-3984. https://doi.org/10.1016/j.atmosenv.2010.06.060
24. Van Nieuwenhuyse, J., Van Schaeybroeck, B., Caluwaerts, S., De Deyn, J., Delcloo, A., De Troch, R., Hamdi, R., ve Termonia, P. (2023) Air-stagnation episodes based on regional climate models part I: evaluation over Europe, Climate Dynamics, 61(5), 2121-2138. https://doi.org/10.1007/s00382-023-06665-2
25. Wang, J. X., ve Angell, J. K. (1999) Air stagnation climatology for the United States (1948-1998). Silver Spring, MD: NOAA/Air Resources Laboratory, Retrieved from https://repository.library.noaa.gov/
26. Wang, L., Li, M., Wang, Q., Li, Y., Xin, J., Tang, X., Du, W., Song, T., Li, T., ve Sun, Y. (2022) Air stagnation in China: Spatiotemporal variability and differing impact on PM2. 5 and O3 during 2013–2018, Science of the Total Environment, 819, 152778. https://doi.org/10.1016/j.scitotenv.2021.152778
27. Wang, X., Dickinson, R. E., Su, L., Zhou, C., ve Wang, K. (2018) PM 2.5 pollution in China and how it has been exacerbated by terrain and meteorological conditions, Bulletin of the American Meteorological Society, 99(1), 105-119. https://doi.org/10.1175/BAMS-D-16-0301.1
28. Wang, X., Wang, K., ve Su, L. (2016) Contribution of atmospheric diffusion conditions to the recent improvement in air quality in China, Scientific reports, 6(1), 36404. https://doi.org/10.1038/srep36404
29. Yang, J., ve Shao, M. (2021) Impacts of extreme air pollution meteorology on air quality in China, Journal of Geophysical Research: Atmospheres, 126(7), e2020JD033210. https://doi.org/10.1029/2020JD033210
30. Yoo, J.-W., Park, S.-Y., Jeon, W., Jung, J., Park, J., Mun, J., Kim, D., ve Lee, S.-H. (2024) Understanding the physical mechanisms of PM2. 5 formation in Seoul, Korea: assessing the role of aerosol direct effects using the WRF-CMAQ model, Air Quality, Atmosphere & Health, 17(8), 1701-1714. https://doi.org/s11869-024-01538-x
31. Zhang, Y., Chen, S. X., ve Bao, L. (2023) Air pollution estimation under air stagnation—A case study of Beijing, Environmetrics, 34(6), e2819. https://doi.org/10.1002/env.2819