Extreme southward swings of the South Indian convergence zone can induce devastating floods over parts of southern Africa. How greenhouse warming affects such southward swings is not well understood. Here we show that, under a high-emissions scenario, the frequency of extreme southward swings doubles from one event per 22 years in the twentieth century to one per 10 years in the twenty-first century with an average increase in rainfall intensity of 20%. The increased frequency is related to faster warming of the African continent than of the Indian Ocean that intensifies northerly winds, and to a poleward migration of Southern Ocean westerlies that drives a pattern of faster subtropical Indian Ocean warming to the south and enhances Atlantic-to-Africa moisture transport, both of which favour a southward swing of the South Indian convergence zone. More frequent southward migration of the South Indian convergence zone might thus indicate increasing flooding risk in parts of southern Africa. Extreme southward swings of the South Indian convergence zone can lead to severe rainfall and flooding in southern Africa. Here the authors show that climate change leads to an increase in the frequency and intensity of such swings.
A resilient society must prepare not only for common harms but also for uncommon vulnerabilities, such as rare disease where the consequences leave no room for failure. Ensuring that people with rare diseases have reliable access to essential care is crucial for fairness and safety in a changing climate.
Political polarization and increasing exposure to extreme weather can shape public engagement with climate change, yet the underlying psychological mechanisms remain unclear. In this Registered Report, we examine how political affiliation, extreme weather exposure and subjective attribution influence climate-relevant information search and decision-making in a US sample (N = 1,451). We combined a process-tracing paradigm within an incentivized decision task involving real carbon emissions with objective data on extreme weather exposure. Democrats attended more to carbon emission information and made more pro-climate choices than Republicans, with no evidence of moderation by objective extreme weather exposure. The subjective attribution of extreme weather to climate change was associated with greater attention to carbon information, more pro-climate choices and moderated the effects of exposure on both outcomes. These findings highlight the importance of political affiliation in climate-relevant decision-making and suggest that extreme weather effects depend less on exposure itself than on how these experiences are interpreted. Mechanisms behind climate decision-making remain unclear. This study shows that political affiliation and subjective attribution shape attention allocation and climate-related choices, with subjective attribution moderating the effects of political affiliation and objective weather exposure.
This year, all three major Rio Conventions — on biodiversity, climate and desertification — convene their respective Conference of the Parties (COP). In advance of the biodiversity COP17, Astrid Schomaker, the executive secretary of the Convention on Biological Diversity, discusses the irrefutable need to integrate biodiversity conservation into broader environmental action to ensure local and global security and prosperity in a rapidly changing world.
Wind is a fundamental driver of land–atmosphere exchange, yet its role in ecosystem water use efficiency (WUE) remains unclear. Here using global eddy-covariance observations combined with Earth system model simulations, we show that WUE declines with increasing wind speed across most terrestrial ecosystems, driven primarily by wind-induced increases in evapotranspiration and secondarily by reductions in gross primary productivity. Mechanistically, stronger winds enhance aerodynamic conductance, strengthen ecosystem–atmosphere coupling and amplify atmospheric water demand. Earth system model simulations capture the negative sensitivity of WUE to wind speed and indicate that future WUE changes will be strongly influenced by wind speed. Under high-emission scenarios, intensified reductions in wind speed enhance WUE, whereas weaker stilling under low-emission scenarios reduces this effect. These results establish wind speed as a previously underappreciated regulator of carbon–water coupling and highlight its importance for predicting ecosystem responses to climate change. The role of wind in ecosystem water use efficiency remains unclear. The authors show that water use efficiency declines with increasing wind speed, driven mainly by increases in evapotranspiration and secondarily by reductions in gross primary productivity.
