Reto Knutti

TL;DR: In this paper, a summary of issues to assist policymakers, a technical summary, and a list of frequently-asked questions are presented, with an emphasis on physical science issues.

TL;DR: The climate change that takes place due to increases in carbon dioxide concentration is largely irreversible for 1,000 years after emissions stop, showing that thermal expansion of the warming ocean provides a conservative lower limit to irreversible global average sea level rise.

TL;DR: A comprehensive probabilistic analysis aimed at quantifying GHG emission budgets for the 2000–50 period that would limit warming throughout the twenty-first century to below 2 °C, based on a combination of published distributions of climate system properties and observational constraints is provided.

TL;DR: The Scenario Model Intercomparison Project (ScenarioMIP) as discussed by the authors is the primary activity within Phase 6 of the Coupled Model Comparison Project (CMIP6) that will provide multi-model climate projections based on alternative scenarios of future emissions and land use changes produced with integrated assessment models.