Climate change will impact urban areas. Decision makers need useful climate information to adapt adequately. This research aims to improve understanding of changes in moisture and temperature projected under climate change in Berlin compared to its surroundings. Simulations for the Representative Concentration Pathway (RCP) 8.5 scenario from the European Coordinated Regional Climate Downscaling Experiment (EURO-CORDEX) 0.11° are analyzed, showing a difference in moisture and temperature variables between Berlin and its surroundings. The running mean over 30 years shows a divergence throughout the twenty-first century for relative humidity between Berlin and its surroundings. Under this scenario, Berlin gets drier over time. The Mann-Kendall test quantifies a robust decreasing trend in relative humidity for the multi-model ensemble throughout the twenty-first century. The Mann-Whitney-Wilcoxon test for relative humidity indicates a robust climate change signal in Berlin. It is drier and warmer in Berlin compared to its surroundings for all months with the largest difference existing in summer. Additionally, the change in humidity for the period 2070–2099 compared to 1971–2000 is larger in the summer months. This study presents results to better understand near surface moisture change and related variables under long-term climate change in urban areas compared to their rural surroundings using a regional climate multi-model ensemble.

Non-technical summary: We summarize what we assess as the past year's most important findings within climate change research: limits to adaptation, vulnerability hotspots, new threats coming from the climate–health nexus, climate (im)mobility and security, sustainable practices for land use and finance, losses and damages, inclusive societal climate decisions and ways to overcome structural barriers to accelerate mitigation and limit global warming to below 2°C.Technical summary: We synthesize 10 topics within climate research where there have been significant advances or emerging scientific consensus since January 2021. The selection of these insights was based on input from an international open call with broad disciplinary scope. Findings concern: (1) new aspects of soft and hard limits to adaptation; (2) the emergence of regional vulnerability hotspots from climate impacts and human vulnerability; (3) new threats on the climate–health horizon – some involving plants and animals; (4) climate (im)mobility and the need for anticipatory action; (5) security and climate; (6) sustainable land management as a prerequisite to land-based solutions; (7) sustainable finance practices in the private sector and the need for political guidance; (8) the urgent planetary imperative for addressing losses and damages; (9) inclusive societal choices for climate-resilient development and (10) how to overcome barriers to accelerate mitigation and limit global warming to below 2°C.Social media summary: Science has evidence on barriers to mitigation and how to overcome them to avoid limits to adaptation across multiple fields.

Climate model output has progressively increased in size over the past decades and is expected to continue to rise in the future. Consequently, the research time expended by Early Career Researchers (ECRs) on data‐intensive activities is displacing the time spent in fostering novel scientific ideas and expanding the frontiers of climate sciences. Here, we highlight an urgent need for a better balance between data‐intensive and foundational climate science activities, more open‐ended research opportunities that reinforce the scientific freedom of the ECRs, and strong coordinated action to provide infrastructure and resources to the ECRs working in under‐resourced environments.

We present a global dataset of urban areas and their rural surroundings, developed within the framework of the CORDEX Flagship Pilot Study on Urban Environments and Regional Climate Change. The dataset is derived from model-specific urban fraction variables and additional static inputs. Urban and rural surrounding areas are delineated using Regional Climate Model (RCM) simulations from the global CORDEX-CORE and European EURO-CORDEX initiatives, focusing on a representative set of megacities worldwide. The analysis was conducted at horizontal resolutions of 25 km globally and 12.5 km for Europe. To facilitate future applications, we provide a Python-based workflow that can be extended for the analysis of additional cities and RCMs, including tools for evaluating the urban climate island effect. The dataset and tools, available via Zenodo and GitHub, offer a consistent and reproducible approach for assessing urban climate change in current and upcoming regional climate projections. This constitutes the first global RCM-based database of urban/rural areas, providing a foundation for future high-resolution model data analysis efforts, such as studies using convection-permitting simulations.