Abstract
We report here extreme daytime and nighttime temperatures, severe heatwaves, and compound hot events recorded in China’ five most densely populated city clusters in summer 2022. New records were set, with daytime maximum temperatures > 42°C in cities along the Yangtze River valley and extreme nighttime temperatures > 30°C. Widespread prolonged heatwaves lasting for > 40 days and compound hot days occurring for > 32 consecutive days were experienced in these city clusters. To explore the possible causes of these extreme events, we analyzed the linkages between the changes in the mean temperatures and hot extremes for different-sized cities in the city clusters. We found that megacities (e.g., Beijing, Shanghai, Guangzhou, etc.) and large cities (e.g., Baoding, Wuxi, Foshan, etc.), especially those located in central and eastern China, experienced unprecedented extreme high temperatures, not only in the daytime but also at night. We observed large increases in the mean temperatures and more frequent and more intense hot extremes in cities affected by both the background global warming and intensified urbanization. Megacities and large cities experienced higher and more frequent extreme temperatures and greater warming trends than medium- and small-sized cities (e.g., Zhangjiakou, Zhenjiang, Yaan, etc.). The evidence of the dependence of temperature trends on a city’ size shows that intensified heat island effects may increase the threat of hot extremes in cities undergoing rapid urbanization.
References
Bader, D. A., R. Blake, A. Grimm, et al., 2018: Urban climate science. Climate Change and Cities: Second Assessment Report of the Urban Climate Change Research Network, C. Rosenzweig, W. D. Solecki, P. Romero-Lankao, et al., Eds., Cambridge University Press, Cambridge, United Kingdom, 27–60, doi: https://doi.org/10.1017/9781316563878.009.
Chen, X. L., and T. J. Zhou, 2018: Relative contributions of external SST forcing and internal atmospheric variability to July–August heat waves over the Yangtze River valley. Climate Dyn., 51, 4403–4419, doi: https://doi.org/10.1007/s00382-017-3871-y.
Chen, Y., and P. M. Zhai, 2017: Revisiting summertime hot extremes in China during 1961–2015: Overlooked compound extremes and significant changes. Geophys. Res. Lett., 44, 5096–5103, doi: https://doi.org/10.1002/2016GL072281.
Deng, K. Q., S. Yang, D. J. Gu, et al., 2020: Record-breaking heat wave in southern China and delayed onset of South China Sea summer monsoon driven by the Pacific subtropical high. Climate Dyn., 54, 3751–3764, doi: https://doi.org/10.1007/s00382-020-05203-8.
He, G. H., Y. J. Xu, Z. L. Hou, et al., 2021: The assessment of current mortality burden and future mortality risk attributable to compound hot extremes in China. Sci. Total Environ., 777, 146219, doi: https://doi.org/10.1016/j.scitotenv.2021.146219.
IPCC, 2021: Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change, V. Masson-Delmotte, P. M. Zhai, A. Pirani, et al., Eds., Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 3–32.
Jones, B., and B. C. O’Neill, 2016: Spatially explicit global population scenarios consistent with the Shared Socioeconomic Pathways. Environ. Res. Lett., 11, 084003, doi: https://doi.org/10.1088/1748-9326/11/8/084003.
Kong, Q. Q., S. B. Guerreiro, S. Blenkinsop, et al., 2020: Increases in summertime concurrent drought and heatwave in Eastern China. Wea. Climate Extrem., 28, 100242, doi: https://doi.org/10.1016/j.wace.2019.100242.
Kuang, W. H., G. M. Du, D. S. Lu, et al., 2021: Global observation of urban expansion and land-cover dynamics using satellite big-data. Sci. Bull., 66, 297–300, doi: https://doi.org/10.1016/j.scib.2020.10.022.
Li, Q. X., and W. J. Dong, 2009: Detection and adjustment of undocumented discontinuities in Chinese temperature series using a composite approach. Adv. Atmos. Sci., 26, 143–153, doi: https://doi.org/10.1007/s00376-009-0143-8.
Liu, X. C., Q. H. Tang, X. J. Zhang, et al., 2018: Projected changes in extreme high temperature and heat stress in China. J. Meteor. Res., 32, 351–366, doi: https://doi.org/10.1007/s13351-018-7120-z.
Lu, R. Y., K. Xu, R. D. Chen, et al., 2023: Heat waves in summer 2022 and increasing concern regarding heat waves in general. Atmos. Ocean. Sci. Lett., 16, 100290, doi: https://doi.org/10.1016/J.AOSL.2022.100290.
Luo, M., and N.-C. Lau, 2017: Heat waves in southern China: Synoptic behavior, long-term change, and urbanization effects. J. Climate, 30, 703–720, doi: https://doi.org/10.1175/JCLI-D-16-0269.1.
Luo, M., and N.-C. Lau, 2019: Amplifying effect of ENSO on heat waves in China. Climate Dyn., 52, 3277–3289, doi: https://doi.org/10.1007/s00382-018-4322-0.
Ma, F., and X. Yuan, 2021: More persistent summer compound hot extremes caused by global urbanization. Geophys. Res. Lett., 48, e2021GL093721, doi: https://doi.org/10.1029/2021GL093721.
Mora, C., T. McKenzie, I. M. Gaw, et al., 2022: Over half of known human pathogenic diseases can be aggravated by climate change. Nat. Climate Change, 12, 869–875, doi: https://doi.org/10.1038/s41558-022-01426-1.
Ren, G. Y., L. Zhang, T. Bian, et al., 2015: Urbanization effect on change of daily temperature at Shijiazhuang weather station. Chinese J. Geophys., 58, 398–410, doi: https://doi.org/10.6038/ccjg20150205. (in Chinese)
Ren, Y. Y., D. Parker, G. Y. Ren, et al., 2016: Tempo-spatial characteristics of sub-daily temperature trends in mainland China. Climate Dyn., 46, 2737–2748, doi: https://doi.org/10.1007/s00382-015-2726-7.
Sen, P. K., 1968: Estimates of the regression coefficient based on Kendall’s tau. J. Amer. Stat. Assoc., 63, 1379–1389, doi: https://doi.org/10.1080/01621459.1968.10480934.
Shi, Z. T., G. S. Jia, Y. H. Hu, et al., 2019: The contribution of intensified urbanization effects on surface warming trends in China. Theor. Appl. Climatol., 138, 1125–1137, doi: https://doi.org/10.1007/s00704-019-02892-y.
Sun, Y., X. B. Zhang, G. Y. Ren, et al., 2016: Contribution of urbanization to warming in China. Nat. Climate Change, 6, 706–709, doi: https://doi.org/10.1038/nclimate2956.
Wang, J., Y. Chen, S. F. B. Tett, et al., 2020: Anthropogenically-driven increases in the risks of summertime compound hot extremes. Nat. Commun., 11, 528, doi: https://doi.org/10.1038/s41467-019-14233-8.
Wang, J., Y. Chen, W. L. Liao, et al., 2021: Anthropogenic emissions and urbanization increase risk of compound hot extremes in cities. Nat. Climate Change, 11, 1084–1089, doi: https://doi.org/10.1038/s41558-021-01196-2.
Witze, A., 2022: Extreme heatwaves: surprising lessons from the record warmth. Nature, 608, 464–465, doi: https://doi.org/10.1038/d41586-022-02114-y.
Yang, Y., C. X. Jin, and S. Ali, 2020: Projection of heat wave in China under global warming targets of 1.5 °C and 2 °C by the ISIMIP models. Atmos. Res., 244, 105057, doi: https://doi.org/10.1016/j.atmosres.2020.105057.
Yu, R., P. M. Zhai, and Y. Chen, 2018: Facing climate change-related extreme events in megacities of China in the context of 1.5°C global warming. Curr. Opin. Environ. Sustain., 30, 75–81, doi: https://doi.org/10.1016/j.cosust.2018.03.008.
Zhai, P. M., Y. F. Yuan, R. Yu, et al., 2019: Climate change and sustainable development for cities. Chinese Sci. Bull., 64, 1995–2001, doi: https://doi.org/10.1360/N972018-00911. (in Chinese)
Zhang, X. B., and F. W. Zwiers, 2004: Comment on “Applicability of prewhitening to eliminate the influence of serial correlation on the Mann-Kendall test” by Sheng Yue and Chun Yuan Wang. Water Resour. Res., 40, W03805, doi: https://doi.org/10.1029/2003WR002073.
Zhang, X. B., L. Alexander, G. C. Hegerl, et al., 2011: Indices for monitoring changes in extremes based on daily temperature and precipitation data. WIREs Climate Change, 2, 851–870, doi: https://doi.org/10.1002/wcc.147.
Zhou, C. L., K. C. Wang, D. Qi, et al., 2019: Attribution of a record-breaking heatwave event in summer 2017 over the Yangtze River delta. Bull. Amer. Meteor. Soc., 100, S97–S103, doi: https://doi.org/10.1175/BAMS-D-18-0134.1.
Acknowledgments
We thank the Editor and reviewers for their thorough review and constructive suggestions.
Author information
Authors and Affiliations
Corresponding author
Additional information
Supported by the China Meteorological Administration (CMA) Special Program on Climate Change and Chinese Academy of Meteorological Sciences (CAMS) Science Development Foundation: Novel Features and Mechanisms of China’ Regional Extreme Events.
Electronic Supplementary Material
Rights and permissions
About this article
Cite this article
Yuan, Y., Liao, Z., Zhou, B. et al. Unprecedented Hot Extremes Observed in City Clusters in China during Summer 2022. J Meteorol Res 37, 141–148 (2023). https://doi.org/10.1007/s13351-023-2184-9
Received:
Revised:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s13351-023-2184-9