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تسجيل مستخدم جديدOzone depletion-induced climate change following a 50 pc supernova
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Ozone in Earths atmosphere is known to have a radiative forcing effect on climate. Motivated by geochemical evidence for one or more nearby supernovae about 2.6 million years ago, we have investigated the question of whether a supernova at about 50 pc could cause a change in Earths climate through its impact on atmospheric ozone concentrations. We used the Planet Simulator (PlaSim) intermediate-complexity climate model with prescribed ozone profiles taken from existing atmospheric chemistry modeling. We found that the effect on globally averaged surface temperature is small, but localized changes are larger and differences in atmospheric circulation and precipitation patterns could have regional impacts.
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