Climate-carbon-cycle interactions and spatial heterogeneity of the late Triassic Carnian pluvial episode

The Carnian Pluvial Episode (CPE; 234-232 million years ago) is an iconic but poorly understood hyperthermal event. Here, we present an integrated high-resolution (~2-10 kyr) multi-proxy record from a Carnian lacustrine succession of the Junggar Basin of northwestern China. We find that the rapid CPE onset (~15.8 kyr) could have been the result of volcanism and subsequent surface carbon-cycle feedbacks. The CPE terrestrial carbon cycling, at a scale of ± 1‰ (δ¹³C_org), displays an in-phase relationship with the 405-kyr-long-eccentricity parameter, paralleling the warmhouse climate-carbon-cycle interactions throughout the Oligo-Miocene. The CPE hydrological cycle was typified by increased aridification in continental interiors and multiple precipitation centres at low-latitude eastern regions of Pangea and at the poles. The carbon and hydrological cycle changes of the CPE include features reminiscent of other warm events, suggesting they may share key characteristics and hold important clues to Earth system functioning.