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Abstract In 2023, the first Polar Postdoc Leadership Workshop convened to discuss present and future polar science issues and to develop leadership skills. The workshop discussions fostered a collective commitment to inclusive leadership within the polar science community among all participants. Here, we outline challenges encountered by underrepresented groups in polar sciences, while also noting that progress has been made to improve inclusivity in the field. Further, we highlight the inclusive leadership principles identified by workshop participants to bring to the polar community as we transition into leadership roles. Finally, insights and practical knowledge we gained from the workshop are shared, aiming to inform the community of our commitment to inclusive leadership and encourage the polar community to join us in pursuing action toward our shared vision for a more welcoming polar science future. 

Abstract The Eocene‐Oligocene transition (EOT) marks the shift from greenhouse to icehouse conditions at 34 Ma, when a permanent ice sheet developed on Antarctica. Climate modeling studies have recently assessed the drivers of the transition globally. Here we revisit those experiments for a detailed study of the southern high latitudes in comparison to the growing number of mean annual sea surface temperature (SST) and mean air temperature (MAT) proxy reconstructions, allowing us to assess proxy‐model temperature agreement and refine estimates for the magnitude of thepCO₂forcing of the EOT. We compile and update published proxy temperature records on and around Antarctica for the late Eocene (38–34 Ma) and early Oligocene (34–30 Ma). Compiled SST proxies cool by up to 3°C and MAT by up to 4°C between the timeslices. Proxy data were compared to previous climate model simulations representing pre‐ and post‐EOT, typically forced with a halving ofpCO₂. We scaled the model outputs to identify the magnitude ofpCO₂change needed to drive a commensurate change in temperature to best fit the temperature proxies. The multi‐model ensemble needs a 30 or 33% decrease inpCO₂, to best fit MAT or SST proxies respectively. These proxy‐model intercomparisons identify decliningpCO₂as the primary forcing of EOT cooling, with a magnitude (200 or 243 ppmv) approaching that of thepCO₂proxies (150 ppmv). However individual model estimates span a decrease of 66–375 ppmv, thus proxy‐model uncertainties are dominated by model divergence. 

Abstract Terrestrial climate records for Antarctica, beyond the age limit of ice cores, are restricted to the few unglaciated areas with exposed rock outcrops. Marine sediments on Antarctica's continental shelves contain records of past oceanic and terrestrial environments that can provide important insights into Antarctic climate evolution. The SHALDRIL II (Shallow Drilling on the Antarctic Continental Margin) expedition recovered sedimentary sequences from the eastern side of the Antarctic Peninsula of late Eocene, Oligocene, middle Miocene, and early Pliocene age that provides insights into Cenozoic Antarctic climate and ice sheet development. Here, we use biomarker data to assess atmospheric and oceanic temperatures and glacial reworking from the late Eocene to the early Pliocene. Analyses of hopanes andn‐alkanes indicate increased erosion of mature (thermally altered) soil biomarker components reworked by glacial erosion. Branched glycerol dialkyl glycerol tetraethers from soil bacteria suggest similar air temperatures of 12°C ± 1°C (1σ,n = 46) for months above freezing for Eocene, Oligocene, and Miocene timeslices but much colder (and likely shorter) periods of thaw during the Pliocene (5°C ± 1°C,n = 4) on the Antarctic Peninsula. TEX₈₆‐based (Tetraether index of 86 carbons) sea surface temperature estimates indicate ocean cooling from 7°C ± 3°C (n = 10) in the Miocene to 3°C ± 1°C (n = 3) in the Pliocene, consistent with deep ocean cooling. Resulting temperature records provide useful constraints for ice sheet and climate model simulations seeking to improve understanding of ice sheet response under a range of climate conditions.