The Artinskian Warming Event: an Euramerican change in climate and the terrestrial biota during the early Permian

One of the most significant climate changes in the history of Earth happened during the late Palaeozoic, with the melting of the Gondwanan ice sheets and a progressive warming that profoundly changed the composition of the global terrestrial biota. Nevertheless, there is a lack of studies on mid-late Cisuralian central Pangaea (present day Europe and North Africa). We have comprehensively revised the well-constrained tetrapod ichnofauna, macroflora, and microflora from the late Cisuralian of the Southern Alps and compared it to other Cisuralian assemblages from Europe and North Africa. The results show a dramatic increase in both diversity and relative abundance of drought-tolerant forms during the Artinskian, at about 287 Ma. This biotic replacement is sudden, conspicuous, widespread and time-equivalent to the biotic replacement observed at the low palaeolatitudes of western Pangaea (present-day western USA) and to a major increase of pCO2 and Na2O values in Euramerican successions. This is possibly related to the eruption of the Tarim Large Igneous Province of NW China and Panjal Traps of NW India that may have caused the final melting of the Gondwanan ice sheets. Consequently, this substantial faunal and floral change is probably driven by a global climatic event (Artinskian Warming Event, AWE) that increased temperature and aridity at the low palaeolatitudes of Pangaea, enhancing the apparent abundance and diversity of drought-tolerant taxa. Further studies are needed to better constrain the timing of this event and verify its full extent, in both the continental and marine realms, as well as to investigate its relationship with contemporary eruptions.