The endPermian mass extinction event (∼252 Mya) is associated with one of the largest global carbon cycle perturbations in the Phanerozoic and is thought to be triggered by the Siberian Traps volcanism. Sizable carbon isotope excursions (CIEs) have been found at numerous sites around the world, suggesting massive quantities of 13 Cdepleted CO 2 input into the ocean and atmosphere system. The exact magnitude and cause of the CIEs, the pace of CO 2 emission, and the total quantity of CO 2 , however, remain poorly known. Here, we quantify the CO 2 emission in an Earth system model based on new compoundspecific carbon isotope records from the Finnmark Platform and an astronomically tuned age model. By quantitatively comparing the modeled surface ocean pH and boron isotope pH proxy, a massive (∼36,000 Gt C) and rapid emission (∼5 Gt C yr −1 ) of largely volcanic CO 2 source (∼−15%) is necessary to drive the observed pattern of CIE, the abrupt decline in surface ocean pH, and the extreme global temperature increase. This suggests that the massive amount of greenhouse gases may have pushed the Earth system toward a critical tipping point, beyond which extreme changes in ocean pH andmore »
Offofequilibrium effects on Kurtosis Along StrangenessNeutral Trajectories
The Beam Energy Scan program at the Relativistic Heavy Ion Collider (RHIC) is searching for the QCD critical point. The main signal for the critical point is the kurtosis of the distribution of proton yields obtained on an event by event basis where one expects a peak at the critical point. However, its exact behavior is still an open question due to outofequilibrium effects and uncertainty in the equation of state. Here we use a simplistic hydrodynamic model that enforces strangenessneutrality, selecting trajectories that pass close to the critical point. We vary the initial conditions to estimate the effect of outofequilibrium hydrodynamics on the kurtosis signal.
 Editors:
 David, G.; Garg, P.; Kalweit, A.; Mukherjee, S.; Ullrich, T.; Xu, Z.; Yoo, I.K.
 Award ID(s):
 1654219
 Publication Date:
 NSFPAR ID:
 10336530
 Journal Name:
 EPJ Web of Conferences
 Volume:
 259
 Page Range or eLocationID:
 10001
 ISSN:
 2100014X
 Sponsoring Org:
 National Science Foundation
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