Antarctic Ozone Hole. Each year the thinning of the protective ozone layer over Antarctica, known as the ozone "hole", expands over Antarctica, sometimes reaching populated areas of South America and exposing them to ultraviolet rays normally absorbed by ozone. On September 22, 2004, ozone thinning over Antarctica reached its maximum extent for the year at 24.2 million square kilometers. The depletion of ozone in the stratosphere is caused chiefly by ozone reacting with chlorine and bromine from industrially manufactured gases. Several small chlorine oxide molecules are involved in the catalytic cycles that lead to the destruction of ozone. As described in the JCE LrnComOnline feature article "Cl2O4 in the Stratosphere. A Module from the Physical Chemistry On-Line Project" by David M. Whisnant, Lisa Lever, and Jerry Howe, students use computational chemistry to investigate a larger chlorine oxide, Cl2O4. The goal of this new feature column is to promote creation, dissemination, and utilization of well-crafted online instructional modules that span the chemistry curriculum (see mission statement of the JCE LrnComOnline column).
Our Secondary School editors work hard to distill all the JCE materials to produce a fraction of particular interest to high school teachers. We call it CLIC.
In recent years we have worked hard to better match our advertisers with our readers. When shopping for chemistry education materials, visit our advertisers' WWW sites first.
Take JCE along on your outreach missions. Copies of the Journal, guest access to JCE Online, our publications catalog, and more are available for your participants.