Nature Climate Change

Antarctic sea ice declined sharply between 2015 and 2017, and this study uses ocean observations and atmospheric data to determine contributing factors. The authors show that thinning of Winter Water in the previous decade, followed by strong winds, brought warm deep water into contact with sea ice.

The radiative impact of microplastic and nanoplastic particles in the atmosphere is not well understood. Here the authors quantify their radiative forcing, finding that they can exceed that of black carbon regionally.

Meeting global temperature targets requires deep mitigation across sectors. Moving away from cost optimality when allocating mitigation by sector, the authors link integrated assessment models and portfolio analysis to identify and balance trade-offs between Sustainable Development Goal indicators.

Assessing risk and adverse impacts associated with climate change is essential to inform adaptation efforts. However, this Perspective argues that knowledge of potentially beneficial impacts is also crucial for adaptation, requiring modifications of current impact and adaptation research frameworks.

The EU Carbon Border Adjustment Mechanism (CBAM) was introduced to curb carbon leakage, but its impact is debated. Using export and emissions data from Indian steel plants, researchers show early evidence that the CBAM could penalize high-emission producers, rather than act as a blanket trade barrier.

The authors develop an early warning system to predict the risks of extreme temperatures for 30,585 vertebrates 1–9 months in advance. They identify species and regions at risk and highlight the potential for early warning systems to maximize management activities that mitigate negative outcomes.

How the balance of microbial methane production and oxidation in freshwater systems will change with warming is unclear. This study uses natural warming experiments to demonstrate that methane emissions increase because oxidation keeps pace with, but cannot exceed, warming-accelerated production.

Blue carbon projects are expanding, yet their implications for tenure security remain uncertain. Analysis of 122 guidance documents reveals that rights are narrowly interpreted and key international obligations are overlooked, leaving rightsholders vulnerable to dispossession and exclusion.

How hailstorms change with warming is not well understood. Here the authors use global projections with different hail proxies to show that hail-prone conditions shift polewards under warming, also shifting crop risk related to hail hazards.

The authors assess the impacts of China’s Grassland Ecological Compensation Policy on climate and maize yields. They demonstrate reduced temperature and increased precipitation, which are linked to increased crop yields that partially offset restoration costs.

As climate change impacts are increasingly apparent, there are changes in society and the political landscape that need to be considered.

Climate debates often frame individual behaviour and systems change as distinct pathways to action. We suggest that social change arises from individuals’ agency within their roles in societal systems, and that this agency should be actively leveraged to achieve meaningful climate change mitigation.