Bummer: Through an alleged causal chain longer than your arm, trace amounts of CO2 may have "a dramatic impact on public health": More skin cancer!

Climate concerns | Science Codex

For decades, scientists have known that the effects of global climate change could have a potentially devastating impact across the globe, but Harvard researchers say there is now evidence that it may also have a dramatic impact on public health.

As reported in a paper published in the July 27 issue of Science, a team of researchers led by James G. Anderson, the Philip S. Weld Professor of Atmospheric Chemistry, are warning that a newly-discovered connection between climate change and depletion of the ozone layer over the U.S. could allow more damaging ultraviolet (UV) radiation to reach the Earth's surface, leading to increased incidence of skin cancer.

In the system described by Anderson and his team, water vapor injected into the stratosphere by powerful thunderstorms converts stable forms of chlorine and bromine into free radicals capable of transforming ozone molecules into oxygen. Recent studies have suggested that the number and intensity of such storms are linked to climate changes, Anderson said, which could in turn lead to increased ozone loss and greater levels of harmful UV radiation reaching the Earth's surface, and potentially higher rates of skin cancer.

"If you were to ask me where this fits into the spectrum of things I worry about, right now it's at the top of the list," Anderson said. "What this research does is connect, for the first time, climate change with ozone depletion, and ozone loss is directly tied to increases in skin cancer incidence, because more ultraviolet radiation is penetrating the atmosphere."