Comment on “Resonant dissociative electron transfer of the presolvated electron to CCl4 in liquid: Direct observation and lifetime of the CCl4∗− transition state” [J. Chem. Phys. 128, 041102 (2008)]

Abstract

A recent paper [J. Chem. Phys.128, 041102 (2008)] reports resonant dissociative electron transfer (RDET) to CCl4 in liquid ethanol. Part of the motivation for this work was the proposed importance of RDET processes for stratospheric ozone chemistry via dissociative electron attachment (DEA) triggered by cosmic ray activity in the polar winter stratosphere. In the present comment, it is argued that the relevance of DEA-induced destruction of chlorofluorocarbons (CFCs) in the polar stratosphere as a possible pathway for rapid chemical ozone destruction should not be a motivation for studies of DEA on CFC molecules; no correlation is observed between polar chemical ozone loss and cosmic ray activity. In any event, the relevance of this process as a key mechanism for the formation of the ozone hole should be presented as an issue debated in the scientific literature rather than as an established scientific fact.

Cosmic-Ray-Driven Reaction and Greenhouse Effect of Halogenated Molecules: Culprits for Atmospheric Ozone Depletion and Global Climate Change

“…68 Note also that no correction of total O 3 in the polar region by the UV solar irradiance has been proposed, as severe polar O 3 loss occurs mainly in the winter and early spring lower polar stratosphere at attitudes of 15-20 km and no solar effect is expected there. 68,69,91,92 This is also evident by the fact that polar total O 3 observed in the summer Antarctic stratosphere showed no 11-year periodic variations, indicating no solar-cycle effects on polar O 3 production. 7 Finally, there is no significant trend in the long-term variation of solar irradiance since the 1970s, 68,97 so no solar effect on the long-term trend of ozone in either polar or the extra-polar region is expected.…”

Cosmic-ray-driven electron-induced reactions of halogenated molecules adsorbed on ice surfaces: Implications for atmospheric ozone depletion and global climate change

“…However, it has been argued that no such a correlation would exist beyond one CR cycles [107], or that this time correlation for total ozone in the low and mid-latitudes is only due to the solar effect and no correlation between CRs and O 3 loss in the polar region would exist [108,109]. It was even argued that no further studies of the CR-driven mechanism for O 3 depletion should be motivated [109]. Facing these criticisms, Lu and co-workers [110,111] have provided strong evidence of the CRE mechanism for the polar ozone hole [15].…”

A brief history of stratospheric ozone research

“…For example WANG et al (2008) assert that DEA-induced heterogeneous decomposition of CFCs "has been proposed to be the key mechanism for the formation of the Earth's ozone hole". However, there is now a number of studies that provide strong arguments, based both on model simulations and on observations, that heterogeneous reactions of CFC on PSC cannot be of substantial importance to polar ozone chemistry (HARRIS et al, 2002;PATRA and SANTHANAM, 2002;MÜLLER, 2003MÜLLER, , 2008.…”