how much gas does a volcano emit
Carbon dioxide (CO2) trapped in low-lying areas can be lethal to people and animals. Carbon dioxide constitutes approximately 0.04% of the air in the Earth's atmosphere. In an average year, volcanoes release between about 180 and 440 million tonnes of carbon dioxide. When this colorless, odorless gas is emitted from volcanoes, it typically becomes diluted to low concentrations very quickly and is not life threatening.