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The Coupled Model Intercomparison Project (CMIP) is one of the biggest international efforts aimed at better understanding the past, present, and future of climate changes in a multi-model context. A total of 21 model intercomparison projects (MIPs) were endorsed in its sixth phase (CMIP6), which included 190 different experiments that were used to simulate 40 000 years and produced around 40 PB of data in total. This paper presents the main findings obtained from the CPMIP (the Computational Performance Model Intercomparison Project), a collection of a common set of metrics, specifically designed for assessing climate model performance. These metrics were exclusively collected from the production runs of experiments used in CMIP6 and primarily from institutions within the IS-ENES3 consortium. The document presents the full set of CPMIP metrics per institution and experiment, including a detailed analysis and discussion of each of the measurements. During the analysis, we found a positive correlation between the core hours needed, the complexity of the models, and the resolution used. Likewise, we show that between 5 %–15 % of the execution cost is spent in the coupling between independent components, and it only gets worse by increasing the number of resources. From the data, it is clear that queue times have a great impact on the actual speed achieved and have a huge variability across different institutions, ranging from none to up to 78 % execution overhead. Furthermore, our evaluation shows that the estimated carbon footprint of running such big simulations within the IS-ENES3 consortium is 1692 t of CO 2 equivalent. As a result of the collection, we contribute to the creation of a comprehensive database for future community reference, establishing a benchmark for evaluation and facilitating the multi-model, multi-platform comparisons crucial for understanding climate modelling performance. Given the diverse range of applications, configurations, and hardware utilised, further work is required for the standardisation and formulation of general rules. The paper concludes with recommendations for future exercises aimed at addressing the encountered challenges which will facilitate more collections of a similar nature. [ABSTRACT FROM AUTHOR]

Convergent environmental crises have triggered scholarly attention towards the question of how great powers understand and engage with the environment, given their role as systemic actors within the international order. Environmental great powers – those that can employ both positive and negative powers to advance or block environmental cooperation – are typically limited to those who have the capability to influence environmental issues, and the responsibility to do so legitimately. Using a constructivist lens, this paper extends this analysis to the role of middle powers, who can influence environmental issues through their support for international cooperation, backed by their actions. We focus on Australia, an oft-cited middle power known for supporting the international rules-based order. By examining Australia's record on two current, interlinked environmental crises, climate change and biodiversity, we show that although it provides legal support for environmental cooperation, it also engages in, and conceals, significant political obstruction to meeting its obligations. Given the need for all states to address the surpassing of safe limits of planetary boundaries, and for its contribution to the destruction of systems upon which humanity depends, we argue that Australia might be deemed an ecocidal middle power. [ABSTRACT FROM AUTHOR]

This paper proposes a conceptual and analytical framework of states' legitimacy-seeking to comprehensively investigate the motivation behind China's climate and environment policy. While previous research has largely overlooked political factors that underlie China's climate policy, this paper argues that these factors are crucial in understanding China's policy changes, which are evident at both domestic and international levels. By examining sources such as government documents, leaders' speeches and authoritative literature, this study contends that China's climate change initiatives are part of a broader effort to enhance domestic and international legitimacy. The issue of climate change has become highly politicised in China under the leadership of President Xi Jinping, and it serves as a crucial test of the ruling party and the state's capacity to govern effectively. As such, legitimacy-seeking is the key driver that links China's domestic measures and international commitments. [ABSTRACT FROM AUTHOR]