IDENTIFICATION OF LONG-TERM CHARACTERISTICS OF CROSSEQUATORIAL NORTHERLY SURGE (CENS) CHANGES FROM HISTORICAL AND FUTURE CLIMATE CONDITIONS

• Main Author: Sevina Danurlintang, Aulya
• Format: Final Project
• Language: Indonesia
• Subjects: Geologi, hidrologi & meteorologi
• Online Access: https://digilib.itb.ac.id/gdl/view/76612
• Institution: Institut Teknologi Bandung

Climate change makes changes to the background climate conditions. As a result, climate change can also affect phenomena on a synoptic scale, such as crossequatorial northerly surge (CENS). Although there are many studies related to CENS, there are still research limitations related to changes in CENS characteristics. This study uses ERA5 data as historical observation data to determine changes in CENS characteristics in the historical period (DJF 1980/1981–2009/2010). In addition, this study uses 3 CMIP6 climate model data with SSP5-8.5 projection scenarios, those are MRI-ESM2-0, INM-CM5-0, and CNRM-CM6-1-HR, to determine changes in CENS characteristics in the near future (DJF 2030/2031– 2059/2060) and far future projection period (DJF 2060/2061–2089/2090). The results of this study indicate that there are changes in the long-term characteristics of CENS in the historical period. CENS frequency shows a decreasing trend with -0.423 events/decade, CENS magnitude shows an increasing trend with -0.0147 m/s/decade, and CENS duration shows an increasing trend with 0.767 days/decade. Of the three characteristics, only the CENS duration showed a significant increasing trend with a 95% confidence level. Then, the three CMIP6 historical simulations can consistently represent spatial patterns associated with CENS, such as mean sea level pressure anomalies, 10 metre winds, and precipitation anomalies, and temporal patterns associated with CENS, such as 10 metre winds and precipitation anomalies. Then, the CENS index threshold appears to be decreasing or weaker, while other CENS characteristics still have large uncertainty in the near future period. In the far future period, the duration of CENS appears to be increasing, while other CENS characteristics still have large uncertainty. This study has not examined the specific phenomena that trigger changes in CENS characteristics in the future.