A correlation analysis is needed to see the relations among the three variables, rainfall with El Niño-Southern Oscillation (ENSO) and Humidity with ENSO. The instability of rainfall and the decrease in the humidity in Bengkulu City can be affected by La Nina and El Nino phenomena. This research aimed to analyze the correlations among rainfall, humidity, and ENSO with Pearson correlation analysis. The rainfall and humidity data were collected from BMKG, and the ENSO data were obtained from NOAA PSL for the 1985-2020 period. The results of the correlation analysis of rainfall and ENSO for the last 35 years generally show a moderately strong correlation. However, a strong correlation in the La Nina phase specifically occurred in 1988-1989, 1998-1999, 1999-2000, 2007-2008 and 2010-2011 with values of 58.6, 40.1, 61.4, 96, 4, and 89.2%. Meanwhile, the correlation >80% (very strong) during the El Nino phase occurred in 1987, 1991-1992, 1997, 2015. The correlation analysis results of humidity and ENSO show little correlation in the La Nina phase of >70% (1988-1989, 1998-1999, 2010-2011) and the El Nino phase of <70% (1997, 2015, 2016). The humidity correlations with ENSO do not influence the humidity change in Bengkulu City. The decrease in the humidity in Bengkulu City can be affected by other factors, such as land use change to housing due to population growth in Bengkulu City.

The Ulu Manna area is classified as an area with high landslide potential because of its location and geological structure, which is hilly. The risk of landslides in the Ulu Manna area due to earthquakes in weak areas can be studied using ground shear strain (GSS). This study aimed to provide information on the potential of landslides in the Ulu Manna area, South Bengkulu Regency Indonesia. The data was collected using the Horizontal-to-Vertical Spectral Ratio (HVSR) method. The study area is 195.8 km2 and consists of 32 data collection points. The data processing was performed using WinMASW 5.2 HVSR and ArcGIS Desktop 10.8.2 software to obtain dominant frequency values, amplification values, subsurface soil vulnerability index values, maximum soil acceleration values, and soil shear strain values. The soil shear strain values obtained are on the order of 10-4 to 10-3, meaning that the dynamic characteristics of the soil in the study area are elastic-plastic. This plastic-elastic nature characterizes the area as an area with high landslide potential