The space shuttle's impact on the stratosphere

Michael J Prather,Anne R Douglass,Malcolm K W Ko,Nien Dak Sze,María M García,Charles H Jackman

doi:10.1029/jd095id11p18583

Abstract

Launch of spacecraft using solid rocket motors leads to release of gaseous and particulate matter in the stratosphere. Concern over these emissions, particularly chlorine, goes back to the Climatic Impact Assessment Program (Hoshizaki, 1975). The buildup of these exhaust products and their perturbation to stratospheric ozone is followed with two‐ and three‐dimensional atmospheric chemical transport models. Chlorine enhancements due to the current rate of shuttle launches is small, on average less than 0.6% above the current background. Other gases emitted from the solid rockets appear to have even smaller global effects, although the impact of particulate alumina remains uncertain.

Highlights

The launchof NASA's SpaceShuttleand similarrockets made with two two-dimensional(latitudeby altitude) models injects chlorine compoundsdirectly into the stratosphere, with completechemistry(AER model:Ko et al [1985; 1989]; adding to the current burden of stratosphericchlorine
The potential depletionsare predictedto be less than 0.2% locally, with damageto the ozonelayerby the SpaceShuttle'ssolidrocket smallerperturbationsto the ozonecolumn
Shuttlesand six Titans per year; it is typical of the current Estimates of the amount and distribution of chlorine released schedule,but it may fall shortof the frequencyneededfor from the launchof the NASA SpaceShuttleandtheTitan IV major spaceprojects

Summary

Launchof spacecrafut singsolidrocketmotorsleadsto releaseof gaseousandparticulatematterin the stratosphere.Concemover theseemissionsp, articularlychlorine,goesback to the Climatic Impact AssessmenPt rogram(Hoshizaki,1975). The buildupof theseexhaustproductsandtheir perturbationto stratospherioczoneis followedwith two- andthree-dimensionaaltmospherichemicaltransportmodels. Chlorineenhancementsdue to the currentrate of shuttlelaunchesis small, on averagelessthan 0.6% abovethe currentbackground.Othergasesemittedfrom the solidrocketsappearto haveeven smaller globaleffects,althoughthe impactof particulatealuminaremainsuncertain

INTRODUCTION

The launch scenario considered here consists of nine

Findings

The exhaust from the solid rocket motors also contains other