Lidar Observations of Mt. Pinatubo Aerosols: Effects on the Global Radiation Budget
Document ID: 79
Stevens, Timothy D.1
Maruvada, S.1
Kane, Timothy J.2
Philbrick, C. Russell1,2
1 The Pennsylvania State University, Applied Research Laboratory, University Park, PA, U.S.A.
2 The Pennsylvania State University, Department of Electrical and Computer Engineering, University Park, PA, U.S.A.
Abstract
Lidar observations of the latitudinal distribution of aerosols arising from Mt. Pinatubo's eruption yield insight into the effects of these particles on global solar radiance.
Introduction
Significant amounts of stratospheric aerosols can cause a cooling of the earth's surface due to the scattering of solar radiation back into space. Likewise a warming of the stratosphere where the particles reside will occur due to absorption of upwelling infrared radiation [ 1]. The eruption of the Pinatubo volcano in the Philippines (15.14°N, 120.35°E) on June 15, 1991, produced the largest impact on the stratosphere ever observed by modern airborne, spaceborne, and groundbased scientific instruments. The volcanic aerosols were ejected into the upper troposphere and the stratosphere to heights above 33 km. Due to their long residence time, the volcanic aerosols were transported around _the globe in about three weeks [2]. The effects are spread in the meridional direction by the interactions of large scale planetary waves with the resivour regions about the equator. By September 27 small amounts were observed as far north as Norway.
Estimates, from the SAGE II experiment ofNASA, place the aerosol mass injected by this eruption between 20 and 30 megatons, approximately twice the amount produced by El Chichon in 1982 [3]. NASA models also predict a surface temperature decrease, in 1992, of about three times the standard deviation of the annual_ global mean [1]. This temperature decrease is sufficient to reverse current global warming trends for the next couple of years. lt is therefore important to study and understand aerosol distribution and variations in the stratosphere to see how they contribute to the thermodynamic exchange processes in the atmosphere.
Keywords: Mt. Pinatubo aerosols, radiation budget, lidar, R. V. Polarstern
| Citation: | "Lidar Observations of Mt. Pinatubo Aerosols: Effects on the Global Radiation Budget", Stevens, T. D., S. Maruvada, T. J. Kane, C. R. Philbrick, Optical Remote Sensing of the Atmosphere, Technical Digest Series, Vol. 5, OSA Proceedings, March 1993, pp. 313 - 316 |