Understanding the early Paleozoic carbon cycle balance and climate change from modelling

The Ordovician global cooling trend observed by several temperature proxies, which coincides with one of the most significant evolutionary diversifications on Earth, is yet to be fully understood. This study presents new simulations pCO2 and surface temperatures using a spatially resolved climate-carbon cycle Earth system model fed refined continental reconstructions estimates solid degassing. First, in order quantify respective roles paleogeography degassing, impact drift alone investigated. done calculating its imprint weathering rates throughout under constant pCO2, testing different topography inputs. Secondly, sensitivity Earth's climate carbon degassing changes investigated coupling cycles GEOCLIM model. Based our experiments we show that, although Early high can replicated within error margins, constraints cannot explain intense over Mid Late Ordovician, even if progressive enhancement weatherability taken into account. By an inverse modelling approach, calculate that theoretical necessary reach proxy-derived for three-to-five times higher compared modern values. Further, simulate following trend, must reduced modern-day values only 30 Myrs. We conclude accepting veracity temperatures, alternative sources but also sinks considered climatic shift period.