Chaopeng Ji, Mu Mu, Bo Qin, Tao Lian, Shijin Yuan, Jie Feng, Xunshu Song, Yuntao Wei, Guokun Dai, Jinyu Wang, Xianghui Fang
{"title":"Toward skillful forecasting of super El Niño events using a diffusion-based westerly wind burst parameterization","authors":"Chaopeng Ji, Mu Mu, Bo Qin, Tao Lian, Shijin Yuan, Jie Feng, Xunshu Song, Yuntao Wei, Guokun Dai, Jinyu Wang, Xianghui Fang","doi":"10.1038/s41612-025-01158-x","DOIUrl":"https://doi.org/10.1038/s41612-025-01158-x","url":null,"abstract":"<p>Forecasting super El Niño remains challenging, partly due to poor representation of westerly wind bursts (WWBs). We developed an artificial intelligence-based denoising diffusion probabilistic model (DDPM) to skillfully parameterize WWBs, capturing their joint modulation by oceanic and atmospheric processes. The DDPM-based scheme effectively captures observed WWBs’ characteristics (e.g., frequency, intensity, and spatial center). When implemented in the Community Earth System Model, it outperforms both the control (CTRL, without WWBs parameterization) and conventional warm pool eastern edge (WPEE)-dependent parameterization in predicting intensity and seasonal phase-locking for super El Niños (1982/83, 1997/98, 2015/16). This improvement stems from DDPM’s realistic WWBs representation, correcting CTRL and WPEE’s biases of overly weak and westward-shifted winds during El Niño growth. Consequently, DDPM produces more realistic eastern Pacific sea surface temperature anomaly warming patterns. These findings underscore WWB's accuracy as key to super El Niño prediction and demonstrate machine learning’s potential for WWB's parameterization.</p>","PeriodicalId":19438,"journal":{"name":"npj Climate and Atmospheric Science","volume":"210 1","pages":""},"PeriodicalIF":9.0,"publicationDate":"2025-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144664568","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jonathan Schmidt, Luca Schmidt, Felix M. Strnad, Nicole Ludwig, Philipp Hennig
{"title":"A Generative Framework for Probabilistic, Spatiotemporally Coherent Downscaling of Climate Simulation","authors":"Jonathan Schmidt, Luca Schmidt, Felix M. Strnad, Nicole Ludwig, Philipp Hennig","doi":"10.1038/s41612-025-01157-y","DOIUrl":"https://doi.org/10.1038/s41612-025-01157-y","url":null,"abstract":"<p>Local climate information is crucial for impact assessment and decision-making, yet coarse global climate simulations cannot capture small-scale phenomena. Current statistical downscaling methods infer these phenomena as temporally decoupled spatial patches. However, to preserve physical properties, estimating spatio-temporally coherent high-resolution weather dynamics for multiple variables across long time horizons is crucial. We present a novel generative framework that uses a score-based diffusion model trained on high-resolution reanalysis data to capture the statistical properties of local weather dynamics. After training, we condition on coarse climate model data to generate weather patterns consistent with the aggregate information. As this predictive task is inherently uncertain, we leverage the probabilistic nature of diffusion models and sample multiple trajectories. We evaluate our approach with high-resolution reanalysis information before applying it to the climate model downscaling task. We then demonstrate that the model generates spatially and temporally coherent weather dynamics that align with global climate output.</p>","PeriodicalId":19438,"journal":{"name":"npj Climate and Atmospheric Science","volume":"30 1","pages":""},"PeriodicalIF":9.0,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144652371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Relative contribution of anthropogenic warming to the unprecedented heatwave in South America in 2023","authors":"Congren Li, Xiaojing Yu, Jianghua Zheng, Mingjiang Deng, Wanqiang Han, Ping Ma","doi":"10.1038/s41612-025-01142-5","DOIUrl":"https://doi.org/10.1038/s41612-025-01142-5","url":null,"abstract":"<p>In 2023, South America experienced an unprecedented heatwave that threatened socioeconomic structures and ecosystems. This study uses attribution analysis to evaluate the contributions of atmospheric circulation patterns and human factors to the heatwave's probability and intensity. The 2023 heatwave is a 1-in-130-year event and a 1-in-65-year event, with and without considering the 2023 heatwave in the fitting, respectively. The large-scale meteorological analysis revealed that the heatwave was driven by an anomalously high-pressure system that formed a heat dome from dry, hot air columns. ALL (all-forcing scenario) and GHG (greenhouse gas scenario) simulations indicate the likelihood of future extreme heatwaves increases by 28.45% [27.60%, 29.30%] (90% confidence interval) and 30.42% [29.51%, 31.33%] (90% confidence interval), respectively, based on data from 1850 to 2014. Insights from Coupled Model Intercomparison Project Phase 6 (CMIP6) models emphasize that human-induced warming significantly contributes to heatwaves, which highlights the need for effective climate adaptation and mitigation strategies.</p>","PeriodicalId":19438,"journal":{"name":"npj Climate and Atmospheric Science","volume":"29 1","pages":""},"PeriodicalIF":9.0,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144652372","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jinyu Wang, Xianghui Fang, Nan Chen, Bo Qin, Mu Mu, Chaopeng Ji
{"title":"A dual-core model for ENSO diversity: unifying model hierarchies for realistic simulations","authors":"Jinyu Wang, Xianghui Fang, Nan Chen, Bo Qin, Mu Mu, Chaopeng Ji","doi":"10.1038/s41612-025-01164-z","DOIUrl":"https://doi.org/10.1038/s41612-025-01164-z","url":null,"abstract":"<p>Despite advances in climate modeling, simulating the El Niño-Southern Oscillation (ENSO) remains challenging due to its spatiotemporal diversity and complexity. To address this, we build upon existing model hierarchies to develop a new unified modeling platform, which provides practical, scalable, and accurate tools for advancing ENSO research. Within this framework, we introduce a dual-core ENSO model (DCM) that integrates two widely used ENSO modeling approaches: a linear stochastic model confined to the equator and a nonlinear intermediate model extending off-equator. The stochastic model ensures computational efficiency and statistical accuracy. It captures essential ENSO characteristics and reproduces the observed non-Gaussian statistics. Meanwhile, the nonlinear model assimilates pseudo-observations from the stochastic model while resolving key air-sea interactions, such as oceanic feedback balances and spatial patterns of sea surface temperature anomalies during El Niño peaks. The DCM effectively captures the realistic dynamical and statistical features of the ENSO diversity and complexity. The computational efficiency of the DCM also facilitates a rapid generation of extended ENSO datasets, overcoming observational limitations.</p>","PeriodicalId":19438,"journal":{"name":"npj Climate and Atmospheric Science","volume":"15 1","pages":""},"PeriodicalIF":9.0,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144630220","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Birthe Marie Steensen, Gunnar Myhre, Øivind Hodnebrog, Erich Fischer
{"title":"Future increase in European compound events where droughts end in heavy precipitation","authors":"Birthe Marie Steensen, Gunnar Myhre, Øivind Hodnebrog, Erich Fischer","doi":"10.1038/s41612-025-01139-0","DOIUrl":"https://doi.org/10.1038/s41612-025-01139-0","url":null,"abstract":"<p>Compound events where droughts end with heavy precipitation can lead to damage to infrastructure, crops and ecosystems that exceed those of an isolated drought or heavy precipitation event due to increased flooding and runoff from the hardened dry ground. Based on regional climate models we show that the occurrence of these compound events (drought ending with one in 100-day precipitation event) during summer in Europe increases by around 35% (+/−22%) for both the mid-century and end-of-century future projections with an intermediate emission scenario compared to present-day. This increase to 97% (+/−84%) for droughts ending in a more extreme precipitation event (occurring approximately once a year) and is greater than the increase in drought and heavy precipitation events separately. Central and Southern Europe are likely to experience the strongest absolute increase. Results highlight the need to prepare for and adapt to these rare but potentially devastating events.</p>","PeriodicalId":19438,"journal":{"name":"npj Climate and Atmospheric Science","volume":"93 1","pages":""},"PeriodicalIF":9.0,"publicationDate":"2025-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144611241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
LingLing Liu, Jin-Yi Yu, Fan Wang, Jianing Wang, YongFu Lin
{"title":"Linking North Pacific eastern subtropical mode water to ENSO: precursor signatures and subtropical cell pathways","authors":"LingLing Liu, Jin-Yi Yu, Fan Wang, Jianing Wang, YongFu Lin","doi":"10.1038/s41612-025-01147-0","DOIUrl":"https://doi.org/10.1038/s41612-025-01147-0","url":null,"abstract":"<p>Mode waters play a crucial role in ocean heat and carbon storage, as well as in climate variability. Here we reveal a strong relationship between the North Pacific Eastern Subtropical Mode Water (NPESTMW) and El Niño-Southern Oscillation (ENSO) events. NPESTMW volume anomalies exhibit significant correlations with the Ocean Niño Index up to nine months in advance. Our analysis identifies two distinct pathways connecting NPESTMW and ENSO development. First, NPESTMW serves as a footprint of the Pacific Meridional Mode, a well-established ENSO precursor. Second, NPESTMW influences tropical Pacific sea surface temperature through the Subtropical Cell. Notably, our findings indicate that stronger NPESTMW volume anomalies are more closely tied to multi-year ENSO events than to single-year development, especially for the La Niña phase. These discoveries offer new insights into the roles of subtropical mode water in shaping ENSO development.</p>","PeriodicalId":19438,"journal":{"name":"npj Climate and Atmospheric Science","volume":"210 1","pages":""},"PeriodicalIF":9.0,"publicationDate":"2025-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144611242","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Diversity of La Niña onset","authors":"Xiao Pan, Tim Li","doi":"10.1038/s41612-025-01141-6","DOIUrl":"https://doi.org/10.1038/s41612-025-01141-6","url":null,"abstract":"<p>Three La Niña onset types were identified by the K-means cluster analysis of equatorial sea surface temperature anomaly evolutions during the past 111 years (1910–2020). The first type is characterized by a slow basin-wide transition from a neutral year to La Niña, driven by tropical North Atlantic (TNA) warming, which induced anomalous easterlies in the equatorial western Pacific through atmospheric Kelvin wave responses. The easterly anomalies initiate a cooling by triggering upwelling oceanic Kelvin waves, shoaling the thermocline, and strengthening the westward zonal currents. The second and third types are a transition from a central Pacific (CP) and a super eastern Pacific (EP) El Niño to La Niña. The former is attributed to the CP El <span>({rm{Ni}}tilde{{rm{n}}}{rm{o}})</span> induced anomalous easterlies in EP that strengthened local surface latent heat flux and anomalous upwelling, whereas the latter is attributed to a substantially shoaling of ocean thermocline associated with the discharge of the preceding super El <span>({rm{Ni}}tilde{{rm{n}}}{rm{o}})</span>. These characteristics differentiate diversified types of La Niña onset.</p>","PeriodicalId":19438,"journal":{"name":"npj Climate and Atmospheric Science","volume":"13 1","pages":""},"PeriodicalIF":9.0,"publicationDate":"2025-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144611244","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Potential tropical cyclone movement and intensification factors imaged by spaceborne SAR","authors":"Guosheng Zhang, Xiaofeng Li, Pakwai Chan, Hui Su","doi":"10.1038/s41612-025-01162-1","DOIUrl":"https://doi.org/10.1038/s41612-025-01162-1","url":null,"abstract":"<p>Spaceborne synthetic aperture radar (SAR) is a microwave sensor that captures tropical cyclones (TCs) with high spatial resolution. Based on three idealized TC parametric wind models, we provide a comprehensive perspective on TC studies using SAR observations, including surface winds, morphology, eye shape, asymmetry, inflow angle, steering flow, secondary eyewalls, vortex Rossby waves, spatial rain bands, and other small-scale dynamics, contributing to a better understanding of TC movement and intensification.</p>","PeriodicalId":19438,"journal":{"name":"npj Climate and Atmospheric Science","volume":"1 1","pages":""},"PeriodicalIF":9.0,"publicationDate":"2025-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144611245","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yi Chen, Men Xia, Penggang Zheng, Yumin Li, Zhouxing Zou, Shengrui Tong, Kun Li, Xin Feng, Lirong Hui, Qi Yuan, Jinjian Li, Jian Zhen Yu, Shuncheng Lee, Tao Wang, Zhe Wang
{"title":"Complex gas-particle partitioning of nitro-phenolic compounds: field-based insights and determination of apparent activity coefficient","authors":"Yi Chen, Men Xia, Penggang Zheng, Yumin Li, Zhouxing Zou, Shengrui Tong, Kun Li, Xin Feng, Lirong Hui, Qi Yuan, Jinjian Li, Jian Zhen Yu, Shuncheng Lee, Tao Wang, Zhe Wang","doi":"10.1038/s41612-025-01156-z","DOIUrl":"https://doi.org/10.1038/s41612-025-01156-z","url":null,"abstract":"<p>Gas–particle partitioning (GPP) of oxygenated semi–volatile organic compounds (SVOCs) is crucial for atmospheric organic aerosol formation, yet large uncertainties persist in its simulation due to challenges in obtaining accurate parameters. This study focuses on nitro–phenolic species (NPs), representative oxygenated SVOCs impacting solar radiative balance and atmospheric chemistry. Concurrent measurements of gaseous and particulate NPs at a subtropical coastal site showed particulate fractions ranging from 8.6% to 53%, which deviated from traditional theoretical estimates by factors of 0.26 to 10<sup>4</sup>. To address these discrepancies, a field-based activity coefficient (<i>ζ</i>) was derived by integrating measured parameters and theoretical considerations. Incorporating <i>ζ</i> into a box model significantly improved simulations for mono–NPs and uncovered a more complex GPP process for di–NPs than previously recognized. The successful application of <i>ζ</i> in a regional model highlights its broader applicability and calls for more quantitative studies for various SVOCs.</p>","PeriodicalId":19438,"journal":{"name":"npj Climate and Atmospheric Science","volume":"149 1","pages":""},"PeriodicalIF":9.0,"publicationDate":"2025-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144611246","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Continuous gap-filled atmospheric N2O record for the past 800,000 years using machine learning techniques","authors":"Nasrin Salehnia, Eunji Byun, Jinho Ahn, Kajal Kumari","doi":"10.1038/s41612-025-01153-2","DOIUrl":"https://doi.org/10.1038/s41612-025-01153-2","url":null,"abstract":"<p>Ice cores are crucial archives of atmospheric greenhouse gas (GHG) concentrations. Despite the importance of nitrous oxide (N<sub>2</sub>O) as a GHG, existing ice core records contain gaps, particularly during glacial periods, due to the high dust content in ice samples that may cause in situ chemical or biological reactions, increasing N<sub>2</sub>O concentration. By developing an iterative process that applies machine learning (ML) models to existing data on CO<sub>2</sub>, CH<sub>4</sub>, and N<sub>2</sub>O from Antarctic ice cores, we simulated a continuous time series of atmospheric N<sub>2</sub>O concentrations for the past 800,000 years (kyr). The continuous N<sub>2</sub>O record allows us to investigate long-term variability and potential climate feedback that would otherwise remain obscured, as spectral analysis of this record has revealed significant N<sub>2</sub>O periodicities of ~100, 41, and 23 kyr. While ML-based simulations cannot fully replace real, artifact-free measurements, they provide a valuable complementary approach to interpreting past climate dynamics, especially when empirical data are limited or compromised.</p>","PeriodicalId":19438,"journal":{"name":"npj Climate and Atmospheric Science","volume":"4 1","pages":""},"PeriodicalIF":9.0,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144594907","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}