The Elevator into the Stratosphere (image) Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research Share Print E-Mail Caption In tropical thunderstorms over the West Pacific air masses and the chemical substances they contain are quickly hurled upward to the edge of the stratosphere. If there are sufficient OH molecules in the atmosphere, the air is extensively cleaned by chemical transformation processes. Where OH concentrations are low, such as those now found in large sections of the tropical West Pacific, the cleaning capacity of the atmosphere is reduced. Credit © Markus Rex, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research Usage Restrictions To be used only in connection with media reports regarding this press release. Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.