UV-B radiation was the Devonian-Carboniferous boundary terrestrial extinction kill mechanism.

ABSTRACT: There is an unexplained terrestrial mass extinction at the Devonian-Carboniferous boundary (359 million years ago). The discovery in east Greenland of malformed land plant spores demonstrates that the extinction was coincident with elevated UV-B radiation demonstrating ozone layer reduction. Mercury data through the extinction level prove that, unlike other mass extinctions, there were no planetary scale volcanic eruptions. Importantly, the Devonian-Carboniferous boundary terrestrial mass extinction was coincident with a major climatic warming that ended the intense final glacial cycle of the latest Devonian ice age. A mechanism for ozone layer reduction during rapid warming is increased convective transport of ClO. Hence, ozone loss during rapid warming is an inherent Earth system process

SUBMITTER: Marshall JEA 

PROVIDER: S-EPMC7253167 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature