Understanding beliefs about climate change is important, but most of the measures used in the literature are unreliable. Instead, this column uses prices of financial products whose payouts are tied to future weather outcomes in the US. These market expectations correlate well with climate model outputs between 2002 and 2018 and observed weather data across eight US cities, and show significant warming trends. When money is at stake, agents are accurately anticipating warming trends in line with the scientific consensus of climate models.
Key observational indicators of climate change in the Arctic, most spanning a 47 year period (1971–2017) demonstrate fundamental changes among nine key elements of the Arctic system. We find that, coherent with increasing air temperature, there is an intensification of the hydrological cycle, evident from increases in humidity, precipitation, river discharge, glacier equilibrium line altitude and land ice wastage. Downward trends continue in sea ice thickness (and extent) and spring snow cover extent and duration, while near-surface permafrost continues to warm. Several of the climate indicators exhibit a significant statistical correlation with air temperature or precipitation, reinforcing the notion that increasing air temperatures and precipitation are drivers of major changes in various components of the Arctic system. […] The Arctic biophysical system is now clearly trending away from its 20th Century state and into an unprecedented state, with implications not only within but beyond the Arctic.
We are already seeing the devastating consequences of global warming, with ever-rising sea levels, extreme storms, prolonged droughts and intensified bushfires. Now, after two years of research and modelling, scientists have come up with a groundbreaking new framework for achieving – and even beating – the target of limiting warming to 1.5°C. The research by leading scientists at the University of Technology Sydney (UTS), the German Aerospace Center and the University of Melbourne, has been funded by the Leonardo DiCaprio Foundation (LDF) as part of its new One Earth initiative. This model is the first to achieve the required negative emissions through natural climate solutions, including the restoration of degraded forests and other lands, along with a transition to 100% renewable energy by mid-century.
Over the past few years, an international team of climate scientists, economists and energy systems modellers have built a range of new “pathways” that examine how global society, demographics and economics might change over the next century. They are collectively known as the “Shared Socioeconomic Pathways” (SSPs). These SSPs are now being used as important inputs for the latest climate models, feeding into the Intergovernmental Panel on Climate Change (IPCC) sixth assessment report due to be published in 2020-21. They are also being used to explore how societal choices will affect greenhouse gas emissions and, therefore, how the climate goals of the Paris Agreement could be met. The new SSPs offer five pathways that the world could take. Compared to previous scenarios, these offer a broader view of a “business as usual” world without future climate policy, with global warming in 2100 ranging from a low of 3.1C to a high of 5.1C above pre-industrial levels.
“an IPCC special report on the impacts of global warming of 1.5 °C above pre-industrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate poverty”
The time has come: the new IPCC report is here! After several years of work by over 800 scientists from around the world, and after days of extensive discussion at the IPCC plenary meeting in Stockholm, the Summary for Policymakers was formally adopted at 5 o’clock this morning. Congratulations to all the colleagues who were there and worked night shifts. The full text of the report will be available online beginning of next week. Realclimate summarizes the key findings and shows the most interesting graphs.
The United Nations Climate Change Conference in Doha, Qatar, took place from 26 November to 8 December 2012. It included the eighteenth session of the Conference of the Parties (COP 18) to the United Nations Framework Convention on Climate Change (UNFCCC) and the eighth session of the Conference of the Parties serving as the Meeting of the Parties to the Kyoto Protocol (CMP 8). The conference also included meetings by five subsidiary bodies: the thirty-seventh sessions of the Subsidiary Body for Scientific and Technological Advice (SBSTA 37) and the Subsidiary Body for Implementation (SBI 37), the second part of the seventeenth session of the Ad hoc Working Group on Further Commitments for Annex I Parties under the Kyoto Protocol (AWG-KP 17), the second part of the fifteenth session of the Ad hoc Working Group on Long-term Cooperative Action under the UNFCCC (AWG-LCA 15) and the second part of the Ad hoc Working Group on the Durban Platform for Enhanced Action (ADP 1).