Contrasts between Antarctic and Arctic ozone depletion

doi:10.1073/pnas.0604895104

Contrasts between Antarctic and Arctic ozone depletion

*Earth System Research Laboratory, National Oceanic and Atmospheric Administration, Boulder, CO 80305; and
^‡Department of Atmospheric Sciences, Colorado State University, Fort Collins, CO 80523

Edited by William L. Chameides, Environmental Defense, New York, NY, and approved November 17, 2006 (received for review June 13, 2006)

Abstract

This work surveys the depth and character of ozone depletion in the Antarctic and Arctic using available long balloon-borne and ground-based records that cover multiple decades from ground-based sites. Such data reveal changes in the range of ozone values including the extremes observed as polar air passes over the stations. Antarctic ozone observations reveal widespread and massive local depletion in the heart of the ozone “hole” region near 18 km, frequently exceeding 90%. Although some ozone losses are apparent in the Arctic during particular years, the depth of the ozone losses in the Arctic are considerably smaller, and their occurrence is far less frequent. Many Antarctic total integrated column ozone observations in spring since approximately the 1980s show values considerably below those ever observed in earlier decades. For the Arctic, there is evidence of some spring season depletion of total ozone at particular stations, but the changes are much less pronounced compared with the range of past data. Thus, the observations demonstrate that the widespread and deep ozone depletion that characterizes the Antarctic ozone hole is a unique feature on the planet.

Footnotes

^†To whom correspondence should be addressed at:
Earth System Research Laboratory, 325 South Broadway, National Oceanic and Atmospheric Administration, Boulder, CO 80305.
E-mail: susan.solomon{at}noaa.gov
Author contributions: S.S. designed research; S.S. performed research; S.S. and R.W.P. analyzed data; and S.S., R.W.P., and D.W.J.T. wrote the paper.
The authors declare no conflict of interest.
This article is a PNAS direct submission.
Freely available online through the PNAS open access option.