The Interaction of Australian Winter Monsoon and East Asian Summer Monsoon and Its Impacts on Convergence Around Kalimantan
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Abstract
The Australian Winter Monsoon (AWM) and East Asian Summer Monsoon (EASM) play a crucial factor in altering the global climate. The two monsoons are closely linked to each other through cross-equatorial flow. As the Australian High anomaly increases, the Western Pacific Subtropical High (WPSH) also increases, resulting in an anticyclone anomaly in Australia and the Western Pacific region that intensifies the AWM and EASM. This study examines the effect of variations between the two monsoons by removing ENSO and IOD signals on meteorological parameters in the Kalimantan region. European Center for Medium-Range Weather Forecasts (ECMWF) Reanalysis v5 data with a resolution of 0.25° × 0.25° is used to examine the effect at the local scale and rainfall data from local observations for 35 years in the June-July-August (JJA) or boreal summer. Composite and correlation analyses were conducted by calculating the regression coefficients between the composite variables and the target variables. The EASM and AWM were also analyzed using Singular Value Decomposition (SVD) to identify the most relevant spatial patterns. This research reveals that when the AWM and EASM increase at once, two connected anticyclone anomalies over the maritime continent trigger easterly wind anomalies, leading to convergence in Kalimantan, which increases the rainfall intensity in the Kalimantan region.
Manuscript Received: 16 March 2024, Accepted: 13 June 2024, Published: 15 March 2025, ORCiD: 0009-0007-8133-7711
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References
W. Chen, Z. Guan, H. Yang and Q. Xu, “East Asian-Australian Monsoon Variations and Their Impacts on Regional Climate during Boreal Summer,” J. Meteor. Soc. Japan, Ser. II, vol. 98, no. 2, pp. 283-297, 2020.
W. Chen and Z. Guan, “A Joint Monsoon Index for East Asian–Australian Monsoons During Boreal Summer,” Atmosph. Sci. Lett., vol. 18, pp. 403-408, 2017.
W. Chen, Z. Guan, Q. Xu and H. Yang, “Variation of Anomalous Convergence Around Kalimantan Island in Lower Troposphere and Its Role in Connecting The East Asian Summer Monsoon and Australian Winter Monsoon,” J. Geophys. Res.: Atmosph., vol. 124, no. 13, pp. 6892-6903, 2019.
L. Chen and R. Wu, “The Role of The Asian/Australian Monsoons and The Southern/Northern Oscillation in The ENSO Cycle,” Theor. Appl. Climatol., vol. 65, pp. 37–47, 2000.
Z. Guan, K. Ashok and T. Yamagata, “Summertime Response of The Tropical Atmosphere to The Indian Ocean Dipole Sea Surface Temperature Anomalies,” J. Meteor. Soc. Japan, vol. 81, pp. 533–561, 2003.
F. Noor, M. Fadli, R. Rustam and D. Catur, “Master Plan Perubahan Iklim Kalimantan Timur,” Buku Dewan Daerah Perubahan Iklim Kalimantan Timur, 2016.
N. Anggraini and B. Trisakti, “Kajian Dampak Perubahan Iklim Terhadap Kebakaran Hutan dan Deforestasi di Provinsi Kalimantan Barat,” J. Penginderaan Jauh, vol. 8, pp. 11-20, 2011.
A. V. Wulandari, N. K. T. Dewi and W. A Swastiko, “Pemanfaatan Data Satelit Himawari 8 Untuk Mendeteksi Sebaran Asap: Studi Kasus Di Kalimantan Dan Sumatera Tanggal 8 Dan 9 September 2015,” Spektra: J. Fisika Dan Aplikasinya, vol. 2, no. 2, pp. 157-164, 2017.