Abstract
Changbaishan volcano, one of the most dangerous volcanoes in northeastern Asia, continuously emits large amounts of volcanic gases (primarily \(\text {CO}_2\) ) in the air, which may cause great disasters to humans and the surrounding environment. In this study, we applied the VIGIL workflow with the DISGAS and TWODEE-2 models to simulate the dispersion of \(\text {CO}_2\) in air at Changbaishan volcano, focusing on two hydrothermally active areas: Julong hot spring area and Tianchi caldera lake. Simulations were conducted under both current and enhanced emission scenarios, considering local meteorological conditions. The results suggest that current emissions are below hazardous thresholds, while enhanced degassing under windless conditions could lead to dangerous \(\text {CO}_2\) accumulation near the ground surface, exceeding 150,000 ppm in extreme scenarios. Furthermore, the influences of modelling parameters, including model selection, simulation duration, and seasonal variations, are also discussed. In particular, for the same release amount, scenarios simulated by the TWODEE-2 model with shorter durations under low wind speeds and high atmospheric pressure conditions could significantly increase the potential risk of \(\text {CO}_2\) dispersion.
Graphical abstract
Schematic diagram of the degassing of Changbaishan volcanic magma through bubbling hot springs and soil micro-seepage and the stratification diagram of the Tianchi caldera lake.
