The analysis of skin surface temperature and water vapor on volcanic eruption (case study: Mt. Kelud)

Abstract

The post-volcanic eruption can be one of main factors in climate variability. The last incident of Kelud eruption had been occurred at 22:50 WIB, 13 February 2014. This paper aims to analyze the climatology of skin surface temperature (SKT), total column water vapor (TCWV), and mixing ratio at 500 mb before eruption from ERA-Interim and the processes before and after eruptions from Weather Research Forecasting (WRF) model simulation. Global Forecast System (GFS) data was used for WRF as initial condition and boundary condition, while ERA-Interim reanalysis dataset was used as a comparison. Bias correction was used to adjust WRF output with ERA-Interim on SKT and TCWV. SKT interval between day and night ranges from 21-23°C (WRF) and 12°C (ERA-Interim). There are 56 SKT WRF and 5 SKT ERA-Interim anomalous day before eruption. TCWV anomalies from WRF have consistent variation with ERA-Interim and there are 2 TCWV anomalies exceed 2 standard deviation. There were no TCWV anomalies detected on ERA-Interim, but were detected on WRF 2 days before and 3 days after eruption above 2 standard deviations. Mixing ratio shows a downward trend before and after the eruption.