Stephen Po-Chedley

TL;DR: In this article, the authors show that the global surface temperature response to CO2 doubling has increased substantially in the Coupled Model Intercomparison Project phase 6 (CMIP6), with values spanning 1.8-5.6k across 27 GCMs and exceeding 4.5K in 10 of them.

TL;DR: In this paper, the authors present evidence that trends in summertime atmospheric circulation may have contributed as much as 60% to the September sea-ice extent decline since 1979, by a tendency towards a stronger anticyclonic circulation over Greenland and the Arctic Ocean with a barotropic structure in the troposphere.

TL;DR: In 2017, the dominant greenhouse gases released into Earth's atmosphere-carbon dioxide, methane, and nitrous oxide-reached new record highs. as mentioned in this paper The annual global average carbon dioxide concentration at Earth's surface for 2017 was 405.0 ± 0.1 ppm, 2.2 ppm greater than for 2016 and the highest in the modern atmospheric measurement record and in ice core records dating back as far as 800 000 years.

TL;DR: The model fingerprint of externally forced seasonal cycle changes is identifiable with high statistical confidence in five out of six satellite temperature datasets and arises from larger mid-latitude warming in the summer hemisphere, which appears to be partly attributable to continental drying.

TL;DR: In this paper, the authors present an important internal mechanism arising from low-frequency Arctic atmospheric variability in models that can cause substantial summer sea ice melting in addition to that due to anthropogenic forcing.