Analyzing paleoclimate changes during the end-Permian using carbon and nitrogen isotopes

The end-Permian mass extinction (EPME, ca. 252 million years ago or MA) is largest mass extinction event with the extinction of 80% to 90% of marine species and 70% of terrestrial species. Negative carbon isotopes excursion observed globally indicate large amounts of carbon dioxide emissions, which was most likely triggered by the Siberian Traps volcanism. These amounts can be compared to current carbon dioxide emission rate which has exceeded 40 billion tons of carbon dioxide per year based on anthropogenic fossil fuels combustions and land use changes. To better understand the origins, rates, and effects of carbon dioxide emissions on the EPME, we analyzed δ13C and δ15N values of sedimentary rocks dated before, during, and after the EPME to reconstruct the paleoclimate. Rock samples from Waili and Dajiang, China and Trøndelag, Norway were decarbonated in HCl to remove all carbonates and were analyzed in the elemental analyzer isotope ratio mass spectrometer (EA-IRMS) to measure the isotopic values precisely and accurately. These measurements will help us better understand Earth’s dynamic systems in the past and present, especially concerning influxes of CO2 to the atmosphere. This will allow us to better predict how massive release of CO2 in the atmosphere may affect climate change by comparing the emission rate during the end-Permian to modern day.