Global tracking of the SO₂ clouds from the June, 1991 Mount Pinatubo eruptions

Abstract

The explosive June 1991 eruptions of Mount Pinatubo produced the largest sulfur dioxide cloud detected by the Total Ozone Mapping Spectrometer (TOMS) during its 13 years of operation: approximately 20 million tons of SO2, predominantly from the cataclysmic June 15th eruption. The SO2 cloud observed by the TOMS encircled the Earth in about 22 days (∼21 m/s); however, during the first three days the leading edge of the SO2 cloud moved with a speed that averaged ∼35 m/s. Compared to the 1982 El Chichón eruptions, Pinatubo outgassed nearly three times the amount of SO2 during its explosive phases. The main cloud straddled the equator within the first two weeks of eruption, whereas the El Chichón cloud remained primarily in the northern hemisphere. Our measurements indicate that Mount Pinatubo has produced a much larger and perhaps longer‐lasting SO2 cloud; thus, climatic responses to the Pinatubo eruption may exceed those of El Chichón.

Composition and evolution of volcanic aerosol from eruptions of Kasatochi, Sarychev and Eyjafjallajökull in 2008–2010 based on CARIBIC observations

“…Thus there is a large spread in estimated residence times. Estimations of the conversion rate of SO 2 following the Pinatubo eruption are less dispersed; 35 days (Bluth and Doiron, 1992), 33 days (Read et al, 1993) and 25 ± 5 as well as 23 ± 5 days (Guo et al, 2004). Except in the work by Guo et al (2004), uncertainty of the estimated residence time has not been given.…”

Albedo Enhancement by Stratospheric Sulfur Injections: A Contribution to Resolve a Policy Dilemma?

“…In the stratosphere, chemical and micro-physical processes convert SO 2 into sub-micrometer sulfate particles. This has been observed in volcanic eruptions e.g., Mount Pinatubo in June, 1991, which injected some 10 Tg S, initially as SO 2 , into the tropical stratosphere (Wilson et al, 1993;Bluth et al, 1992). In this case enhanced reflection of solar radiation to space by the particles cooled the earth's surface on average by 0.5 • C in the year following the eruption (Lacis and Mishchenko, 1995).…”

“…Second, to derive the radiative forcing caused by the presence of 1 Tg S in the stratosphere, we adopt a simple approach based on the experience gained from the Mount Pinatubo volcanic eruption. For the Mount Pinatubo eruption, Hansen et al (1992) calculated a radiative cooling of 4.5 W/m 2 caused by 6 Tg S, the amount of S that remained in the stratosphere as sulfate six months after the eruption from initially 10 Tg S (Bluth et al, 1992). Linear downscaling results in a sulfate climate cooling efficiency of 0.75 W/m 2 per Tg S in the stratosphere.…”

An Estimation of the Radiative Effect in the Stratosphere due to the Pinatubo Aerosol

“…The SO2 amount injected is detected by the Total Ozone Mapping Spectrometer as approximately 20 megatons, which is nearly three times that of the 1982 El Chichon eruption in Mexico (Bluth et al, 1992), and is possibly the largest in this century. The SO2 gas is converted to H2SO4 vapor and then condensed into a sulfate aerosol, forming a volcanic aerosol layer with the ash particle.…”