The ESRL's research findings provide a sound scientific basis for decisions made in industry and government which are related to ozone layer protection, air quality improvement, and climate change understanding. ESRL scientists work to identify and understand the processes that deplete the ozone layer, and they have leading roles in developing "state-of-the-science" assessment reports for use by national and international decisionmakers.

Some examples of accomplishments from the ESRL's research on stratospheric ozone are:

• Data gathered in Antarctica confirmed an ESRL researcher's theory that the Antarctic ozone hole is caused by human-made chlorine compounds and that polar stratospheric clouds enhance the ozone destruction chemistry.
• The ESRL has participated in several international field experiments (most recently in 1999-2000, the SAGE III Ozone Loss and Validation Experiment) to characterize the chemical processes involved in seasonal ozone destruction in the Arctic stratosphere, where large springtime ozone losses have been observed in many of the recent years.
• Through laboratory and theoretical studies, ESRL scientists have advanced scientific understanding of the heterogeneous processes that cause ozone depletion in the midlatitude stratosphere, establishing key links to volcanic aerosol abundance and cirrus cloud occurrence.
• Theoretical, laboratory, and field research at the ESRL has helped to assess the effects of subsonic and supersonic aircraft on the ozone layer and climate (including the first measurements of the exhaust gases and particles emitted by a supersonic aircraft while in flight in the stratosphere).
• Laboratory and theoretical work have helped to assess the "ozone friendliness" of proposed substitutes for ozone-depleting substances.
• ESRL scientists have developed and applied a new method to provide real-time analysis of the chemical composition of individual atmospheric particles.