Climate Change 2021—The Physical Science Basis

The Intergovernmental Panel on Climate Change (IPCC) is the United Nations body responsible for assessing the science related to climate change. The Sixth Report from IPCC Working Group 1 published in August 2021 paints a very sombre picture for the future. This report was commented on in a news item by the International Science Council (ISC) on behalf of its members, of which IUPAC is a founding member.

ESD Ideas: Global climate response scenarios for IPCC assessments

IPCC Working Group I has long employed socioeconomic scenarios, based on discrete storylines, to sample the uncertainty in future forcing of the climate system, but analogous scenarios to sample the uncertainty in the global climate response have not been employed. Here, we argue that to enable development of robust climate policies this gap should be addressed, and we propose a simple methodology.

ESD Ideas: a simple proposal to improve the contribution of IPCC WGI to the assessment and communication of climate change risks

The purpose of the Intergovernmental Panel on Climate Change (IPCC) is to provide policy-relevant assessments of the scientific evidence about climate change. Policymaking necessarily involves risk assessments, so it is important that IPCC reports are designed accordingly. This paper proposes a specific idea, illustrated with examples, to improve the contribution of IPCC Working Group I to informing climate risk assessments.

Agency and climate change: a quantitative-structuralist approach to the assignment of moral agency in mitigation

<p>This article uses the IPCC Working Group III’s latest report on mitigation of climate change as its material. The ambition is to investigate how the IPCC assigns moral agency to non-experts. For this, the article analyzes whether the terms “citizens”, “stakeholders”, “the public” and “laypeople” are presented as barriers to, drivers for or neutral towards mitigation measures. The “public” stand out in the IPCC report as a much larger barrier to mitigation than the other groups. This article relates these finding to work conducted by Brian Wynne (1991) and Mike Michael (2009) regarding perception of the public by scientific assessments. This article documents that the IPCC Working Group III tends to replicate stereotypes of the public from such scientific assessments.</p>

Integrating and differentiating meanings in tweeting about the fifth Intergovernmental Panel on Climate Change (IPCC) report

The publication of the fifth Intergovernmental Panel on Climate Change (IPCC) Working Group 1 report in September 2013 was highly debated on Twitter. In this paper we focused on tweets that mention “IPCC”, and in particular the content and sentiment of the tweets sent by tweeters that were identified as unconvinced or as convinced towards the scientific basis of global warming. Our results indicate that the content and sentiment of those convinced reflect mainly information sharing activities instead of expressing opinions or participation in the debate. Climate change science is, however, challenged by some unconvinced tweeters who tend to use more negative words in their tweets. Our theoretical contribution is on the processes of meaning making around the IPCC report in relation to different groups of tweeters. We identify how certain words may be given different meanings by different groups, and how certain words have a differentiating function between the groups and integrating function within the groups. Our results increase our knowledge about the content of climate change debate in social media and on Twitter in particularly and contribute to research interested in how words function as differentiating and integrating meanings between and within social groups.

Dahe Qin: time is limited to curb global warming

The landmark international accord reached in the UN climate meeting in Paris last December stipulates the goal of limiting global warming to less than 2°C by 2100. This goal has a solid scientific basis, defined after intensive global research by scientists of the Intergovernmental Panel on Climate Change (IPCC) through modeling future landscapes under different global warming scenarios, showing that 2°C of global warming is the upper limit for maintaining a sustainable Earth. Dahe Qin, an Academician of the Chinese Academy of Sciences and Co-Chair of IPCC Working Group, has participated in climate change research for more than two decades, and knows very well the consequences of 2°C warming. In a recent interview with NSR, Qin says quite clearly, ‘Since time is limited for us to halt global warming, to achieve the rosy 2°C target, we must decrease human-produced green-house gas emissions by 40%–70% by 2050, as compared to levels from 2010, and zero (additional) emissions by 2100. This goal is unlikely to be achieved in the high-carbon emission scenario’. Currently, Qin is busy preparing the IPCC 6th Assessment Report (AR6) of IPCC with other scientists to be released in 2022. He indicates that the AR6 report will propose ‘Shared Socioeconomic Pathways (SSPs)’ that emphasize the local effects of global warming, and bring out constructive and specific recommendations for each area and country to deal with the threat and to maintain sustainable development.

IS THE IPCC’s 5TH ASSESSMENT A DENIER OF POSSIBLE MACROECONOMIC BENEFITS FROM MITIGATING CLIMATE CHANGE?

This review summarizes what we know about the macroeconomics of mitigating climate change over the period 2010 to 2100 as presented in the 2014 IPCC Working Group III report. The review finds that little more, if anything, has been learned about the macroeconomics of mitigating climate change over the long run since the 2007 IPCC report. Furthermore, while the 2014 report is quite self-critical about the serious weaknesses in its methodologies, the self-criticisms are not explicitly taken into account when the net macroeconomic costs of mitigation are reported. Nor do the research teams that run the integrated assessment models relied on in the report utilize any systematic methodology for assessing the inherent uncertainty in the macroeconomic results reported. Thus, the basic quantitative “findings” are misleading — and, perhaps, even deceptive — in part because they appear to preclude the possibility of large macroeconomic benefits from mitigating climate change.