Investigation the Impact of Equatorial-Rossby Waves on Extreme Rainfall in Java, Indonesia Mochamad Khoirul Rifai(a)(b), Eny Latifah(a*), Hari Wisodo(a), and Cahyo Aji Hapsoro(a)
(a) Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Negeri Malang, Jl. Semarang 5, Malang, 65145, Indonesia
(b) Junior High School of Darul Faqih Malang Indonesia, Jl. Gapura 197, Malang, 65158, Indonesia
Climate change has posed an urgent threat not only to the present generation but also to future generations. Even though climate change shows a very complex scheme, the pattern of change can still be observed and predicted. One of the changes that arise is the occurrence of fluctuations in rainfall to extreme rain and changes in other meteorological conditions. In this study, we conducted an in-depth investigation of the impact of Equatorial-Rossby (ER) waves on extreme rainfall in the region of Java Island, Indonesia. Based on an extensive station database (2000 to 2019) and the gridded Asian Precipitation-Highly Resolved Observational Data Integration Toward Evaluation of Water Resources (APHRODITE) product (2000 to 2019), we show that severe weather associated with extreme rainfall extremes in Java during the rainy season can also be attributed to ER waves. Evidence is presented that Equatorial Rossby (ER) waves significantly modulate daily rainfall extremes over Java Island. The convectively active (suppressed) phases of ER waves increase the probability of extreme rainfall by up to 45%, while the suppressed phases decrease this by up to 28%. In addition, the analysis of multiple wave events indicates that the ER waves^ positive (negative) interference leads to an amplification (suppression) of extreme rainfall probability. Overall, the results suggest that ER waves can provide an essential source of predictability for extreme rainfall events over Java Island.
Keywords: Climate change- Extreme rainfall- ER waves- APHRODITE- Java Island.
