Friday, March 6, 2009

Mt Pinitubo Eruption Summer 1991



The eruption of Mt. Pinatubo in June 1991 was the second largest terrestrial eruption of the 20th century (Novaruption in 1912). This eruption ejected massive amounts of aerosols in the stratosphere. While global surface temperature dropped in the subsequent months, this caused an overall warming of the stratosphere in the tropical latitudes by several degrees due to absorption of radiation by the aerosols. Here, MERRA monthly means of 70mb temperature from August and then December of 199o are subtracted from August and December of 1991 to show that stratospheric warming by about 2 to 4 degrees C as the ejecta traversed the globe at this level during the subsequent months after the eruption.