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The 2023 World Climate Research Programme (WCRP) Open Science Conference underscored the critical need for increased climate change mitigation and adaptation efforts, along with enhanced climate knowledge and decision-making systems. This Perspective discusses climate intervention (CI) within WCRP’s research framework, emphasizing three main approaches: terrestrial carbon dioxide removal (CDR), marine CDR, and solar radiation modification (SRM). As global anthropogenic greenhouse gas emissions continue to rise, CI strategies are increasingly recognized as potentially critical supplements to traditional mitigation methods. We call for WCRP to take a leadership role in CI research, highlighting the need for inclusivity and collaboration, especially with researchers from the Global South, to establish a firm scientific foundation for an equitable and comprehensive assessment of the benefits and risks of CI approaches relative to the risks of anthropogenic climate change.

Abstract Stratospheric Aerosol Injection (SAI) is a proposed method of climate intervention aiming to reduce the impacts of human‐induced global warming by reflecting a portion of incoming solar radiation. Many studies have demonstrated that SAI would successfully reduce global‐mean surface air temperatures; however the vast array of model scenarios and strategies result in a diverse range of climate impacts. Here we compare two SAI strategies—a quasi‐ equatorial injection and a multi‐latitude off‐equatorial injection—simulated with the UK Earth System Model (UKESM1), both aiming to reduce the global‐mean surface temperature from that of a high‐end emissions scenario to that of a moderate emissions scenario. We compare changes in the surface and stratospheric climate under each strategy to determine how the climate response depends on the injection location. In agreement with previous studies, an equatorial injection results in a tropospheric overcooling in the tropics and a residual warming in the polar regions, with substantial changes to stratospheric temperatures, water vapor and circulation. Previous comparisons of equatorial versus off‐equatorial injection strategies are limited to two studies using different versions of the Community Earth System Model. Our study evaluates how the climate responds in UKESM1 under these injection strategies. Our results are broadly consistent with previous findings, concluding that an off‐equatorial injection strategy can minimize regional surface temperature and precipitation changes relative to the target. We also present more in‐depth analysis of the associated changes in Hadley Circulation and regional temperature changes, and call for a new series of inter‐model SAI comparisons using an off‐equatorial strategy.

Abstract Borneo Vortices (BVs) are weather systems that are responsible for devastating hydro-climatic extremes and significant losses of life and property in Southeast Asia. The typical resolution of most current climate models is insufficient to resolve these high-impact, synoptic-scale weather systems. Here, an ensemble of high-resolution models projects that future BVs may become less frequent and more stationary, driven by the weakening of the Northeast monsoon flow and associated cold surges across North Borneo. However, substantial increases in both the intensity and the total amount of precipitation from BVs are projected. Such changes are driven by the more humid and convectively unstable lower troposphere. As a result, the contribution of BVs to the accumulation of both total precipitation and extreme precipitation is projected to increase considerably in the vicinity of the southern South China Sea, making individual BVs more threatening to the adjacent coastal regions.

Solar geoengineering has been proposed as a means of mitigating the warming effects of climate change, yet the consequences of such action remain uncertain. Here, using a general circulation model, the authors evaluate the effect of stratospheric aerosol injection on tropical cyclone activity.