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Rain use efficiency (RUE) quantifies the ecosystem's capacity to use precipitation water to assimilate atmospheric CO 2 . The spatial distribution of RUE and its drivers across the Australian continent is largely unknown. This knowledge gap limits our understanding of the possible contribution of Australian ecosystems to global carbon assimilation. This study investigates the spatial distribution of RUE across diverse terrestrial ecosystems in Australia. The results show that RUE ranges from 0.43 (1st percentile) to 3.10 (99th percentile) g C m -2  mm -1 with a continental mean of 1.19 g C m -2  mm -1 . About 68 % of the spatiotemporal variability of RUE can be explained by a multiple linear regression model primarily contributed by climatic predictors. Benchmarked by the model estimation, drainage-diverging/converging landscapes tend to have reduced/increased RUE. The model also revealed the impact of increasing atmospheric CO 2 concentration on RUE. The continental mean RUE would increase by between 29.3 and 64.8 % by the end of this century under the SSP5-8.5 scenario in which the CO 2 concentration is projected to double from the present level. This increase in projected RUE is attributed to the assumed greening effect of increasing CO 2 concentration, which does not consider the saturation of CO 2 fertilisation effect and the warming effect on increasing wildfire occurrence. Under the SSP1-2.6 scenario, RUE would decrease by about 7 %. This study provides baseline RUEs of various ecosystems in Australia for investigating the impacts of human interferences and climate change on the capacity of Australian vegetation to assimilate atmospheric CO 2 under given precipitation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

In the light of inadequate global emissions mitigation, geoengineering – solar radiation management and carbon dioxide removal – is increasingly being positioned and problematized by some researchers, policymakers, and advocates as a partial solution for avoiding catastrophic levels of warming. However, there are concerns that geoengineering may serve as a rhetorical tactic for delaying emissions reduction. As the news media field is an important space in which storylines surrounding geoengineering are created and circulated, the manner in which media actors discuss these topics is an important factor that can legitimate some policy pathways and close off others. In this paper, we analyze patterns in news media coverage of geoengineering in Australia to identify four dominant storylines: "a symptom of systems failure", "silver buckshot", "the Faustian bargain", and "time for plan B". We consider the implication of these storylines for the role that geoengineering may play in the Australian climate policy regime. We identify a risk geoengineering may be positioned as a rhetorical tactic for delaying emissions reduction. However, we note that the storylines in the public sphere provide a basis for public debate that engages critically with geoengineering, engaging with risks and differentiating solar radiation management from carbon dioxide removal. [ABSTRACT FROM AUTHOR]