Volcano

:This article is about volcanoes. For the action movie, see Volcano (movie). For other meanings of the word eruption, see eruption (disambiguation)

Effects of volcanoes

The concentrations of different volcanic gases can vary considerably from one volcano to the next. Water vapor is typically the most abundant volcanic gas, followed by carbon dioxide and sulfur dioxide. Other principal volcanic gases include hydrogen sulfide, hydrogen chloride, and hydrogen fluoride. A large number of minor and trace gases are also found in volcanic emissions, for example: hydrogen, carbon monoxide, and volatile metal chlorides.

Related Topics:
Water vapor - Carbon dioxide - Sulfur dioxide - Hydrogen sulfide - Hydrogen chloride - Hydrogen fluoride - Hydrogen - Carbon monoxide

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Large, explosive volcanic eruptions inject water vapor (H2O), carbon dioxide (CO2), sulfur dioxide (SO2), hydrogen chloride (HCl), hydrogen fluoride (HF) and ash (pulverized rock and pumice) into the stratosphere to heights of 10-20 miles above the Earth's surface. The most significant impacts from these injections come from the conversion of sulfur dioxide to sulfuric acid (H2SO4), which condenses rapidly in the stratosphere to form fine sulfate aerosols. The aerosols increase the reflection of radiation from the Sun back into space and thus cool the Earth's lower atmosphere or troposphere; however, they also absorb heat radiated up from the Earth, thereby warming the stratosphere. Several eruptions during the past century have caused a decline in the average temperature at the Earth's surface of up to half a degree (Fahrenheit scale) for periods of one to three years. The sulfate aerosols also promote complex chemical reactions on their surfaces that alter chlorine and nitrogen chemical species in the stratosphere. This effect, together with increased stratospheric chlorine levels from chlorofluorocarbon pollution, generates chlorine monoxide (ClO), which destroys ozone (O3). As the aerosols grow and coagulate, they settle down into the upper troposphere where they serve as nuclei for cirrus clouds and further modify the Earth's radiation balance. Most of the hydrogen chloride (HCl) and hydrogen fluoride (HF) are dissolved in water droplets in the eruption cloud and quickly fall to the ground as acid rain. The injected ash also falls rapidly from the stratosphere; most of it is removed within several days to a few weeks. Finally, explosive volcanic eruptions release the greenhouse gas carbon dioxide and thus provide a deep source of carbon for biogeochemical cycles.

Related Topics:
Ozone - Carbon

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Gas emissions from volcanoes are a natural contributor to acid rain.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Volcanic activity now releases about 130 to 230 teragrams (145 million to 255 million short tons) of carbon dioxide each year.

Related Topics:
Short ton - Carbon dioxide

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Volcanic eruptions may inject an aerosol of particles and chemicals in the Earth's atmosphere. Large injections may have visual effects and affect global climate through climate forcing.

Related Topics:
Aerosol - Earth's atmosphere - Climate forcing

~ ~ ~ ~ ~ ~ ~ ~ ~ ~