The Analysis of tropical cyclones that occurred in the southern sea of Java during the period 2004-2019 and their effects on sea-atmospheric conditions

Abstract

Tropical cyclones are an important part of the atmospheric circulation system, which transfers heat from the equatorial region to higher latitudes. The birth of a tropical cyclone will have an impact on increasing the intensity of heavy rain, wave height, strong winds, and the potential for lightning. The purpose of this study is to analyse tropical cyclones and their impact on ocean and atmospheric conditions that occur in the southern of Java. The data used in this study is hourly rainfall data, Madden Julian Oscillation (MJO), wind (direction and speed), significant wave height, sea surface temperature, and sea level pressure hourly from the European Centre for Medium-Range Weather Forecasts (ECMWF). The method used in this study is averaging hourly data into daily data for each sea-atmospheric parameter during the 16-years observation period (2004-2019), and representing it in the form of descriptive daily on before, being and after the occurrence of tropical cyclones. From the results of the analysis it can be concluded that there were 17 tropical cyclones which mostly occurred in April, resulting in a significant increase in intensity of sea-atmospheric parameters (rainfall, significant wave height, and wind direction & speed), but decreased for sea level pressure. As from the Riley tropical cyclone event that occurred on (24-26) January 2019, rainfall increased in intensity to 951 mm/day, significant wave heights reaching more than 4 m with wind speeds of more than 17 m/sec, sea level pressure is less than 947 hPa, and the average MJO condition is in phase 2, 3, 4, or 5, with a strong period.