Atmospheric Research最新文献_第9页

Contrasting microphysics and environmental drivers of weak and intense convection-induced extreme precipitation: Insights from GPM DPR observations 对比弱对流和强对流诱导极端降水的微物理和环境驱动因素：来自GPM DPR观测的见解

IF 4.4 2区地球科学 Q1 METEOROLOGY & ATMOSPHERIC SCIENCES

Atmospheric Research

Pub Date : 2026-01-08 DOI: 10.1016/j.atmosres.2026.108762

Zelin Wang , Xiong Hu , Weihua Ai , Shensen Hu , Junqi Qiao , Xianbin Zhao

Under global warming, extreme precipitation events (EPEs) have become frequent worldwide, with unclear microphysical differences in convective clouds. The weak and intense convection-induced EPEs (WeEPEs and InEPEs, respectively) over South China are identified with 10-year spaceborne dual-frequency precipitation radar observations. Results suggest that most EPEs occur in morning and nighttime. The distribution of WeEPEs (land-prevalent) and InEPEs (ocean-prevalent) is regulated by ocean thermal gradients, moisture transport, and orographic lifting. Weak sea surface temperature (SST) gradients and southerly moisture transport generate offshore moisture centers. The humid environment in the ocean may help the formation of WeEPEs. Conversely, strong SST gradients, coupled with stronger southerly moisture transport form inland moisture centers, with orographic forcing enhancing upward motion for strong convection. Weak convection generates extreme precipitation through synergistic increase in particle size and concentration below the 0 °C level, with high concentration being more critical. For oceanic events, InEPEs show a slightly larger particle diameter increase (0.11 mm) below the 0 °C level. However, WeEPEs have a much greater concentration increase (4.34 dB), resulting in a larger reflectivity factor increase (7.58 dBZ). For the most extreme precipitation, even if one of the warm-rain process and the ice-phase process dominates, the other still plays a significant role. Across eventsof different regions, continental WeEPEs reach peak rates through ice-particle melting (16.1 mm/h) and warm-rain coalescence to enhance particle size (70.6 mm/h); marine InEPEs (102.02 mm/h) rely on high liquid water path and efficient coalescence for maximum rates (warm-rain contribution: 43.3 mm/h).

在全球变暖背景下，极端降水事件在全球范围内频繁发生，对流云的微物理差异不明确。利用10年星载双频降水雷达观测资料，对华南地区的弱对流激电现象（WeEPEs）和强对流激电现象（InEPEs）进行了识别。结果表明，EPEs大多发生在早晨和夜间。陆地环流和海洋环流的分布受海洋热梯度、水汽输送和地形抬升的调节。弱海温梯度和偏南水汽输送形成近海水汽中心。海洋中潮湿的环境可能有助于WeEPEs的形成。相反，强烈的海温梯度，加上内陆水汽中心较强的南向水汽输送，地形强迫增强了强对流的上升运动。弱对流在0℃以下通过粒子大小和浓度的协同增加产生极端降水，其中高浓度更为关键。对于海洋事件，InEPEs显示在0°C以下颗粒直径增加略大（0.11 mm）。然而，WeEPEs的浓度增加幅度更大（4.34 dB），导致反射率因子增加幅度更大（7.58 dBZ）。对于最极端的降水，即使暖雨过程和冰相过程中的一个占主导地位，另一个仍然起着重要作用。在不同区域的事件中，大陆WeEPEs通过冰粒融化（16.1 mm/h）和暖雨合并（70.6 mm/h）达到峰值速率；海洋InEPEs （102.02 mm/h）依靠高液态水路径和高效聚结来获得最大速率（暖雨贡献：43.3 mm/h）。

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引用次数: 0

Impact of Rossby wave trains triggered by two successive typhoons in 2023 on local air pollutant concentrations in China 2023年连续两次台风引发的罗斯比波列对中国局部空气污染物浓度的影响

IF 4.4 2区地球科学 Q1 METEOROLOGY & ATMOSPHERIC SCIENCES

Atmospheric Research

Pub Date : 2026-01-08 DOI: 10.1016/j.atmosres.2026.108768

Xin Liu , Jianing Feng , Lu Liu , Hongxiong Xu , Dajun Zhao , Hui Wang , Yike Zhou

Air pollution is strongly linked to local and synoptic-scale atmospheric conditions, and tropical cyclones (TCs) are recognized as high-wind systems that facilitate pollutant scavenging. A key question is whether TC-triggered Rossby wave trains exert direct or remote indirect influences on pollutant concentrations. Using multi-source reanalysis datasets, this study examined the dynamic impacts of the Rossby wave trains from two successive TCs in 2023 (Doksuri, TC1; Khanun, TC2) on central China's pollutant concentrations. Results showed a prominent Rossby wave train was excited by TC1; its alternating anticyclone (A) - cyclone (C) structure drove periodic high-low pressure oscillations in the study area. Pollutant concentrations correlated with wave train phases: cyclonic phases (TC1/TC2/C1) brought strong ascent, enhanced winds, and precipitation, reducing PM2.5 and CO rapidly; anticyclonic phases (A0/A1/A2) caused subsidence and weak winds, worsening diffusion and increasing pollutants. TC1 directly affected local pollution by passing through the area. TC2 propagated northward over the ocean with no direct impact on the study area, but its wave train blocked mid-latitude energy transport, forcing mid-latitude high-pressure energy southward and inducing secondary pollution. This study is the first to quantify TC-Rossby wave train effects on pollutant diffusion (direct/indirect), providing a novel perspective for TC-air pollution links.

空气污染与当地和天气尺度的大气条件密切相关，热带气旋（tc）被认为是促进污染物清除的大风系统。一个关键问题是tc触发的罗斯比波列是否对污染物浓度产生直接或远程间接影响。利用多源再分析数据，研究了2023年连续两个tc （Doksuri, TC1; Khanun, TC2）的rosssby波列对中国中部污染物浓度的动态影响。结果表明：TC1激发出明显的罗斯比波列；其反气旋(A) -气旋(C)交替结构驱动研究区的周期性高低压振荡。污染物浓度与波列相相关：气旋相（TC1/TC2/C1）带来了强上升、强风和强降水，使PM2.5和CO迅速降低；反气旋阶段（A0/A1/A2）造成下沉和弱风，扩散恶化和污染物增加。TC1穿过该地区，直接影响了当地的污染。TC2在海洋上空向北传播，对研究区无直接影响，但其波列阻挡了中纬度能量输送，迫使中纬度高压能量南下，造成二次污染。本研究首次量化了tc - rosby波列对污染物扩散的影响（直接/间接），为tc -空气污染联系提供了新的视角。

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引用次数: 0

Traffic and PM10 in Veneto region (northeastern Italy): The lesson of the 2020 lockdown 威尼托地区（意大利东北部）的交通和PM10: 2020年封锁的教训

IF 4.4 2区地球科学 Q1 METEOROLOGY & ATMOSPHERIC SCIENCES

Atmospheric Research

Pub Date : 2026-01-08 DOI: 10.1016/j.atmosres.2026.108766

Denise Pernigotti , Mario Marcello Miglietta

The COVID-19 lockdown in 2020 represented a unique opportunity to evaluate the way reduced traffic may influence air pollution levels. In the present study, this analysis is performed in the Veneto region, northeastern Italy, one of the most polluted areas in Europe, in the eastern Po Valley. During the first month of the COVID-19 lockdown period, the concentrations of fine particles (PM10) fell by 20–25% in the area, which corresponded to a 30–40% decrease in NO₂ emissions, mostly attributed to lower traffic volumes.

In order to understand if the specific atmospheric conditions of the period affected the decrease in PM10 concentration, meteorological data from ground stations and radio-soundings, together with ERA5 reanalysis data, were analysed to better define the role of meteorology in the reduced pollution concentrations. The analysis does not identify significant changes in the meteorological conditions.

The improvement in the concentrations of PM10 during the lockdown period emphasizes the potential benefits of traffic reduction in achieving air quality goals. Unfortunately, current policy plans are insufficient, failing the 39% reduction in traffic emissions declared as necessary by the Veneto region to comply with EU standards. This consideration highlights the urgent need for significant changes in traffic management strategies in the region.

2020年新冠肺炎疫情封锁为评估交通减少可能影响空气污染水平的方式提供了一个独特的机会。在本研究中，该分析是在意大利东北部威尼托地区进行的，这是欧洲污染最严重的地区之一，位于波河东部。在新冠肺炎疫情封锁期间的第一个月，该地区的细颗粒物（PM10）浓度下降了20-25%，相当于二氧化氮排放量下降了30-40%，这主要是由于交通量减少。

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引用次数: 0

Global monsoon variability in a 1.5 °C warming climate: Observational changes and end-century projections 1.5°C变暖气候下的全球季风变率：观测变化和世纪末预估

IF 4.4 2区地球科学 Q1 METEOROLOGY & ATMOSPHERIC SCIENCES

Atmospheric Research

Pub Date : 2026-01-08 DOI: 10.1016/j.atmosres.2026.108765

Ricky Anak Kemarau , Zulfaqar Sa'adi , Najeebullah Khan , Bassim Mohammed Hashim , Leonardo Goliatt , Sajjad Firas Abdulameer , Zaher Mundher Yaseen , Shamsuddin Shahid

Monsoon systems underpin the water, food, and economic security of over two-thirds of the global population, yet they are entering a state of instability as global temperatures have now surpassed +1.5 °C above pre-industrial levels. This crossing of the 1.5 °C threshold raises a critical problem: Are monsoon onset, duration, and extreme rainfall already shifting in detectable, regionally differentiated ways? Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 framework, we screened 784 peer-reviewed studies (2000–2024) and synthesized 72 high-quality articles. A complementary global diagnostic using Climate Hazards Group InfraRed Precipitation with Stations (CHIRPS; 1981–2024) ensured uniform comparison across monsoon regions. Results reveal onset shifts of ±15 days, rainfall-intensity increases of +10–60%, and duration changes of ±15 days, with the strongest signals in South Asia, East Asia, the Western North Pacific, and Southeast Asia. Attribution using CMIP5/CMIP6, ERA5, TRMM, GPM, and IMERG identifies El Niño–Southern Oscillation (ENSO), Indian Ocean Dipole (IOD), sea-surface temperature anomalies, and greenhouse-gas (GHG)–aerosol interactions as dominant drivers. Although seasonal totals often change modestly, clustering of extremes and lengthening dry spells markedly elevate compound flood–drought risk. This review establishes the first harmonized global baseline of observed monsoon change and highlights urgent needs for convection-permitting regional models, improved subseasonal prediction, expanded observational networks, and increased representation of African and South American monsoon systems.

季风系统支撑着全球三分之二以上人口的水、粮食和经济安全，但随着全球气温比工业化前水平高出+1.5 °C以上，季风系统正在进入一种不稳定状态。1.5 °C阈值的跨越引发了一个关键问题：季风的发生、持续时间和极端降雨是否已经以可检测的、区域差异的方式发生变化？使用系统评价和荟萃分析首选报告项目（PRISMA） 2020框架，我们筛选了784项同行评议的研究（2000-2024），并合成了72篇高质量的文章。利用气候灾害组红外站降水（CHIRPS; 1981-2024）进行的补充性全球诊断确保了各季风区的统一比较。结果表明，南亚、东亚、北太平洋西部和东南亚地区的降水信号最强，降水开始变化为±15 d，降雨强度增加+ 10-60%，持续时间变化为±15 d。利用CMIP5/CMIP6、ERA5、TRMM、GPM和IMERG进行归因，确定El Niño-Southern涛动（ENSO）、印度洋偶极子（IOD）、海面温度异常和温室气体(GHG) -气溶胶相互作用是主要驱动因素。尽管季节总量通常变化不大，但极端事件的聚集性和干旱期的延长显著提高了水旱复合风险。这篇综述建立了观测到的季风变化的第一个统一的全球基线，并强调了对允许对流的区域模式、改进的亚季节预测、扩大观测网络以及增加非洲和南美季风系统代表性的迫切需要。

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引用次数: 0

Understanding the spatial heterogeneity of black carbon variation drivers in China: Views from explainable machine learning 理解中国黑碳变化驱动因素的空间异质性：来自可解释机器学习的观点

IF 4.4 2区地球科学 Q1 METEOROLOGY & ATMOSPHERIC SCIENCES

Atmospheric Research

Pub Date : 2026-01-06 DOI: 10.1016/j.atmosres.2026.108749

Huang Zheng , Weiwei Chen , Xiaohui Bi , Nan Chen , Cheng Wu , Mingming Zheng , Shaofei Kong

Differences in black carbon (BC) emissions and diverse climate zones in China result in significant spatial heterogeneity of BC levels. Understanding the roles of emissions, meteorological conditions, and other factors in BC variation is important for mitigating its adverse effects. This study conducted synchronous observations of BC in Changchun (CC), Tianjin (TJ), Wuhan (WH), and Guangzhou (GZ) during winter. Results showed that BC levels were highest in WH compared to the other cities (p < 0.001). Simulations using the Flexible Particle Dispersion (FLEXPART) model and BC emission inventories quantified the contributions from local transport and different sectors. Results indicated that local emissions were the dominant geographical source of observed BC levels at all four sites. BC from residential, commercial, and other sectors was the dominant source in TJ, WH, and GZ. Using the SHapley Additive exPlanations (SHAP) method, emissions were identified as the predominant factor influencing BC variation at the four sites. While changes in meteorological conditions were the most influential factor contributing to BC concentration increases as air quality worsened from clean to polluted in CC, TJ, and WH. Regarding the impacts of features on model outputs, emissions showed a linear relationship with simulated BC, while the effects of transport and meteorological conditions exhibited spatial heterogeneity. This study highlights the need for continuous reduction of BC emissions to decrease ambient BC levels, and this recommendation can be extended to other parts of the country.

中国黑碳排放的差异和不同气候带导致黑碳排放水平的空间异质性显著。了解排放、气象条件和其他因素在BC变化中的作用对于减轻其不利影响非常重要。本研究冬季在长春（CC）、天津（TJ）、武汉（WH）和广州（GZ）进行了BC同步观测。结果显示，与其他城市相比，WH的BC水平最高（p < 0.001）。利用柔性粒子分散（FLEXPART）模型和BC排放清单进行模拟，量化了当地运输和不同部门的贡献。结果表明，本地排放是四个站点观测到的BC水平的主要地理来源。来自住宅、商业和其他部门的BC是TJ、WH和GZ的主要来源。利用SHapley加性解释（SHAP）方法，确定了排放是影响4个站点BC变化的主要因素。在CC、TJ和WH，随着空气质量从清洁到污染的恶化，气象条件的变化是导致BC浓度增加的最重要因素。在特征对模型输出的影响方面，排放与模拟BC呈线性关系，而运输和气象条件的影响则表现出空间异质性。这项研究强调了持续减少BC排放以降低环境BC水平的必要性，这一建议可以推广到该国其他地区。

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引用次数: 0

Associations between the thermal spring timing variability and atmospheric teleconnection patterns over the past six decades in Finland 芬兰近60年温泉时间变率与大气遥相关模式的关系

IF 4.4 2区地球科学 Q1 METEOROLOGY & ATMOSPHERIC SCIENCES

Atmospheric Research

Pub Date : 2026-01-06 DOI: 10.1016/j.atmosres.2026.108752

Sadegh Kaboli , Ville Kankare , Ali Torabi Haghighi , Cintia Bertacchi Uvo , Elina Kasvi

The timing of the spring season in the boreal region is shifting under global warming, with profound impacts on ecosystems and hydrological processes. However, the mechanisms driving this transition and its considerable interannual variability are not well described, especially regarding the influence of large-scale atmospheric teleconnection patterns. This study examines the temporal variability of the observed thermal spring season across Finland, a boreal country warming faster than the global average. Key spring timing indices, including onset, end, duration, and growing season onset, were calculated and analyzed using high-resolution (1 km × 1 km) daily mean temperature data from 1961 to 2023. Spatial and temporal patterns were identified through Empirical Orthogonal Function (EOF) decomposition, and their associations with major atmospheric teleconnection patterns were examined. Results indicated that during the past six decades, the spring onset has advanced by 2–6 days/decade, with the most pronounced changes in the coastal and southwestern parts of the country. The duration of the spring season has extended by 3–6 days/decade in the northern areas and along the southwestern coast. The early spring onset was associated with a strong positive phase of the Arctic Oscillation (AO), and delayed spring end and growing season onset were linked to the positive phase of the East Atlantic–West Russia (EAWR) pattern. By contrast, an early growing season start was linked to the positive phase of the North Atlantic Oscillation (NAO). The duration of the thermal spring season showed a strong association with the Scandinavian (SCA) pattern.

在全球变暖的影响下，北方地区春季的时间正在发生变化，对生态系统和水文过程产生了深远的影响。然而，驱动这种转变的机制及其相当大的年际变率没有得到很好的描述，特别是关于大尺度大气遥相关型态的影响。本研究考察了芬兰观测到的温泉季节的时间变异性，芬兰是一个比全球平均变暖速度更快的北方国家。利用1961 ~ 2023年高分辨率（1 km × 1 km）日平均气温资料，计算并分析了春季开始、结束、持续时间和生长季节开始等关键时间指标。通过经验正交函数（EOF）分解确定了时空格局，并分析了它们与主要大气遥相关格局的相关性。结果表明：近60 a来，春季开始时间以2 ~ 6 d / a的速度提前，沿海和西南地区变化最为显著；在北部地区和西南沿海，春季的持续时间每十年延长3-6天。早春与北极涛动（AO）强正相相关，晚春结束和生长期开始与东大西洋-西俄罗斯（EAWR）型正相相关。相比之下，生长季节的提前开始与北大西洋涛动（NAO）的正相位有关。温泉季节的持续时间与斯堪的纳维亚（SCA）模式有很强的相关性。

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引用次数: 0

Atmospheric CO₂ concentration gradients at the coastal region of the Yangtze River Delta: Patterns and drivers 长江三角洲沿海地区大气CO 2浓度梯度：模式与驱动因素

IF 4.4 2区地球科学 Q1 METEOROLOGY & ATMOSPHERIC SCIENCES

Atmospheric Research

Pub Date : 2026-01-05 DOI: 10.1016/j.atmosres.2026.108746

Yi Lin , Honggang Lv , Kehan Chen , Peng Guo , Yifei Jiang , Lin Xiao , Tienan Zhao , Haiyan Wang , Yuanyuan Chen , Kunpeng Zang , Shuangxi Fang

Atmospheric carbon dioxide (CO₂), the primary anthropogenic greenhouse gas, is a critical tracer for understanding carbon-cycle–climate feedback. Despite intense industrialization and population density, the Yangtze River Delta (YRD) lacks high-frequency in situ CO₂ observations in its coastal and marine-influenced zones. In this study, the continuous atmospheric CO₂ measurements collected between December 2020 and December 2022 at an urban tower in Shanghai and a coastal background site in Shengsi were analyzed. Results reveal a distinct bimodal diurnal cycle in Shanghai, primarily driven by local anthropogenic emissions, whereas Shengsi exhibits a unimodal pattern more closely coupled to biospheric processes and marine dilution. Nighttime data from Shanghai station reliably represents urban background concentrations, as the stable concentration performance, less planetary boundary layer (PBL) and anthropogenic impacts. Wind and trajectory analyses link CO₂ enhancement at Shanghai to emissions from northern and northwestern sectors, whereas Shengsi concentrations are modulated by ocean-atmosphere carbon exchange—as evidenced by correlations with sea surface temperature, salinity, and pressure, alongside stronger negative links to normalized difference vegetation index (NDVI) and air temperature compared to Shanghai. Furthermore, partial least squares regression (PLSR) further highlights the dominance of local emissions at Shanghai (< 200 km scale) and oceanic/biospheric drivers at Shengsi, with regional transport amplifying variability across scales. These findings advance understanding of CO₂ spatiotemporal variability in coastal megaregions and provide an empirical basis for improving top-down carbon flux estimates and informing targeted climate mitigation strategies in eastern China.

大气中的二氧化碳（CO 2）是主要的人为温室气体，是了解碳循环-气候反馈的关键示踪剂。尽管工业化程度高，人口密度大，但长江三角洲沿海和海洋影响区缺乏高频的原位CO 2观测。在本研究中，对2020年12月至2022年12月在上海城市塔楼和嵊泗沿海背景站点收集的连续大气CO₂测量数据进行了分析。结果表明，上海呈现明显的双峰型日循环，主要受当地人为排放驱动，而嵊泗呈现单峰型日循环，与生物圈过程和海洋稀释密切相关。上海站夜间数据可靠地代表了城市背景浓度，浓度表现稳定，行星边界层（PBL）和人为影响较小。风和轨迹分析将上海的CO₂增加与北部和西北部的排放联系起来，而嵊泗的CO₂浓度受海洋-大气碳交换的调节——与海面温度、盐度和压力相关，与归一化植被指数（NDVI）和气温有更强的负相关。此外，偏最小二乘回归（PLSR）进一步强调了上海（200公里尺度）的局地排放和嵊泗的海洋/生物圈驱动因素的主导地位，区域运输放大了跨尺度的变异。这些发现促进了对沿海特大区域CO 2时空变异的认识，并为改进自上而下的碳通量估算和提供有针对性的气候减缓策略提供了经验基础。

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引用次数: 0

MCF-XCO2: A cross-mission consistency and fusion framework for integrating multi-satellite XCO2 observations MCF-XCO2：用于整合多卫星XCO2观测的跨任务一致性和融合框架

IF 4.4 2区地球科学 Q1 METEOROLOGY & ATMOSPHERIC SCIENCES

Atmospheric Research

Pub Date : 2026-01-05 DOI: 10.1016/j.atmosres.2026.108747

Yutang Yu , Wenjie Tian , Lili Zhang , Tao Yu , Yu Wu , Tianhai Cheng

Carbon satellites, as an essential means of obtaining atmospheric XCO₂ concentration, play a key role in monitoring the global carbon cycle. However, the differences in observation platforms, resolutions, and inversion algorithms among different satellites lead to apparent inconsistencies among multi-source XCO₂ data, which limits the joint application and comprehensive analysis of the data. In this paper, we develop a framework named MCF-XCO₂ (Multi-source Consistency Fusion of XCO₂) for correcting multi-source satellite XCO₂ observations and performing uncertainty-weighted fusion. The method leverages high-precision satellite products as references, while minimizing the need for direct ground-based correction, to enhance the consistency and overall accuracy of multi-source observations. Based on this framework, multi-source satellite data, including GOSAT, GOSAT-2, OCO-2, and OCO-3, were integrated to construct a sparsely gridded global XCO₂ fusion dataset at 0.01° × 0.02° nominal spatial resolution and nominal daily sampling, reflecting available observations. The findings indicate that the fused dataset shows improved coverage in grids with available observations compared to individual satellite products, improved accuracy, and better consistency over time. Independent validation against TCCON ground-based observations further confirms the method's effectiveness, with R² = 0.91, RMSE = 1.09 ppm, bias = 0.07 ppm, and MRE = 0.2 %. The spatial and temporal dynamic analysis of the fused dataset reveals the typical spatial structure and seasonal variation of global carbon concentration, demonstrating the potential application of this dataset in studying the carbon cycle. The MCF-XCO₂ framework is also designed to accommodate future satellite missions, supporting timely updates and extended temporal coverage.

碳卫星作为获取大气XCO2浓度的重要手段，在全球碳循环监测中发挥着关键作用。然而，由于不同卫星观测平台、分辨率和反演算法的差异，导致多源XCO2数据存在明显的不一致性，限制了数据的联合应用和综合分析。在本文中，我们开发了一个名为MCF-XCO2 （Multi-source Consistency Fusion of XCO2）的框架，用于校正多源卫星XCO2观测数据并进行不确定性加权融合。该方法利用高精度卫星产品作为参考，同时最大限度地减少直接地基校正的需要，以提高多源观测的一致性和整体精度。基于该框架，对GOSAT、GOSAT-2、OCO-2和OCO-3多源卫星数据进行整合，以0.01°× 0.02°标称空间分辨率和标称日采样为标准，构建了一个稀疏网格化的全球XCO2融合数据集。研究结果表明，与单个卫星产品相比，融合后的数据集在网格中的可用观测数据覆盖率更高，精度更高，并且随着时间的推移具有更好的一致性。对TCCON地面观测数据的独立验证进一步证实了该方法的有效性，R2 = 0.91, RMSE = 1.09 ppm, bias = 0.07 ppm, MRE = 0.2%。融合数据的时空动态分析揭示了全球碳浓度的典型空间结构和季节变化，展示了该数据在碳循环研究中的潜在应用。MCF-XCO2框架还设计用于适应未来的卫星任务，支持及时更新和扩展时间覆盖。

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引用次数: 0

Case study of aircraft icing in-cloud measurements and explicit supercooled water prediction in Eastern China 中国东部地区飞机结冰云中测量与显式过冷水预报实例研究

IF 4.4 2区地球科学 Q1 METEOROLOGY & ATMOSPHERIC SCIENCES

Atmospheric Research

Pub Date : 2026-01-05 DOI: 10.1016/j.atmosres.2026.108748

Liping Luo , Ming Xue , Xin Xu , Lin Deng , Junxia Li , Rong Zhang

In the morning of 12 November 2022, severe aircraft icing occurred over Anhui Province, Eastern China during weather modification operations. In-situ airborne measurements revealed the presence of a substantial concentration of supercooled droplets with effective diameter exceeding 45

μ

m, and liquid water content (LWC) above 1.2 g m⁻³ during the icing event.

Given the importance of microphysical parameterization (MP) scheme for icing conditions, simulations using different multi-moment MP schemes, i.e., WDM6, NSSL, Milbrandt-Yau (MY) schemes, are conducted at 1-km grid spacing for the case. Comparisons against satellite observations indicate that the general evolution of the frontal system and surface precipitation are well reproduced by the simulations. However, all simulations underpredict upper-level clouds with cloud-top temperature below 240 K over the northeastern part of the front. Besides, WDM6 scheme produces ice cloud-top area (CTA) closest to satellite observations but only produces approximately half of the observed CTA for supercooled cloud tops. The Milbrandt-Yau scheme shows superior performance in simulating the cloud top features during the icing event. Examinations of explicit supercooled cloud water (SCW) prediction skills indicate that WDM6 generates excessive total number concentration (Nt) of small SCW, with Nt reaching up to 10¹¹ m⁻³ and effective diameter (ED) below 20

μ

m. In contrast, the NSSL scheme produces significantly larger SCW particles but substantially lower Nt at approximately 10⁷ m⁻³ and ED of above 200

μ

m. Notably, the particle size distribution of SCW predicted by MY scheme is more realistic compared with in-situ aircraft measurements.

2022年11月12日上午，在人工影响天气作业期间，中国东部安徽省上空发生严重的飞机结冰。现场航空测量显示，在结冰过程中存在大量有效直径超过45 μm的过冷液滴，液态水含量（LWC）超过1.2 g m−3。考虑到微物理参数化（MP）方案对结冰条件的重要性，在1 km网格间距下，使用不同的多矩MP方案（即WDM6、NSSL、Milbrandt-Yau （MY）方案）进行模拟。与卫星观测结果的比较表明，模拟可以很好地再现锋面系统和地面降水的一般演变。然而，所有模拟都低估了锋面东北部云顶温度低于240 K的高层云。此外，WDM6方案产生的冰云顶面积（CTA）与卫星观测值最接近，但仅产生过冷云顶CTA的约一半。Milbrandt-Yau方案在模拟结冰过程中的云顶特征方面表现出优异的性能。对显式过冷云水（SCW）预测技术的检验表明，WDM6产生了过量的小SCW总数浓度（Nt）， Nt高达1011 m−3，有效直径（ED）低于20 μm。相比之下，NSSL方案产生更大的SCW颗粒，但在约107 m−3和ED大于200 μm时，Nt显著降低。值得注意的是，与现场飞机测量结果相比，MY方案预测的水样粒径分布更为真实。

{"title":"Case study of aircraft icing in-cloud measurements and explicit supercooled water prediction in Eastern China","authors":"Liping Luo , Ming Xue , Xin Xu , Lin Deng , Junxia Li , Rong Zhang","doi":"10.1016/j.atmosres.2026.108748","DOIUrl":"10.1016/j.atmosres.2026.108748","url":null,"abstract":"<div><div>In the morning of 12 November 2022, severe aircraft icing occurred over Anhui Province, Eastern China during weather modification operations. In-situ airborne measurements revealed the presence of a substantial concentration of supercooled droplets with effective diameter exceeding 45 <span><math><mi>μ</mi></math></span>m, and liquid water content (LWC) above 1.2 g m<sup>−3</sup> during the icing event.</div><div>Given the importance of microphysical parameterization (MP) scheme for icing conditions, simulations using different multi-moment MP schemes, i.e., WDM6, NSSL, Milbrandt-Yau (MY) schemes, are conducted at 1-km grid spacing for the case. Comparisons against satellite observations indicate that the general evolution of the frontal system and surface precipitation are well reproduced by the simulations. However, all simulations underpredict upper-level clouds with cloud-top temperature below 240 K over the northeastern part of the front. Besides, WDM6 scheme produces ice cloud-top area (CTA) closest to satellite observations but only produces approximately half of the observed CTA for supercooled cloud tops. The Milbrandt-Yau scheme shows superior performance in simulating the cloud top features during the icing event. Examinations of explicit supercooled cloud water (SCW) prediction skills indicate that WDM6 generates excessive total number concentration (<em>Nt</em>) of small SCW, with <em>Nt</em> reaching up to 10<sup>11</sup> m<sup>−3</sup> and effective diameter (<em>ED</em>) below 20 <span><math><mi>μ</mi></math></span>m. In contrast, the NSSL scheme produces significantly larger SCW particles but substantially lower <em>Nt</em> at approximately 10<sup>7</sup> m<sup>−3</sup> and <em>ED</em> of above 200 <span><math><mi>μ</mi></math></span>m. Notably, the particle size distribution of SCW predicted by MY scheme is more realistic compared with in-situ aircraft measurements.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"334 ","pages":"Article 108748"},"PeriodicalIF":4.4,"publicationDate":"2026-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145902906","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

K-means clustering analysis of autumn rainfall patterns over West China and their underlying mechanisms 中国西部秋季降水模式的k均值聚类分析及其机制

IF 4.4 2区地球科学 Q1 METEOROLOGY & ATMOSPHERIC SCIENCES

Atmospheric Research

Pub Date : 2026-01-04 DOI: 10.1016/j.atmosres.2026.108745

Han Zhang, Ke Fan

Through k-means clustering analysis, this study identified three dominant anomalous patterns of autumn rainfall over West China: (1) a region-wide positive anomalies in precipitation, (2) a south-positive–north-negative dipole pattern, and (3) a west-positive–east-negative dipole pattern. The first two patterns account for most of the explained variance annually. The first pattern is influenced primarily by a strengthened and westward-extended western Pacific subtropical high and an intensified East Asian subtropical jet (EAJ), driven mainly by negative sea surface temperature (SST) anomalies in the tropical central-eastern Pacific. Reduced snow cover over the Tibetan Plateau also plays a moderating role by altering the thermal forcing that affects the EAJ. The second pattern is associated mainly with an anomalous anticyclone over the South China Sea and a weakened, southward-shifted EAJ, which are closely linked to El Niño-like SST anomalies in the tropical central-eastern Pacific and cold SST anomalies in the eastern North Atlantic. The above mechanisms were verified using the Linear Baroclinic Model and the ECHAM5 model.

通过k-means聚类分析，确定了中国西部秋季降水的3种主要异常模式：(1)区域性降水正异常，(2)南正北负偶极子模式，(3)西正东负偶极子模式。前两种模式解释了每年的大部分可解释方差。第一种模式主要受西太平洋副热带高压和东亚副热带急流（EAJ）增强和向西扩展的影响，主要受热带中东部太平洋海温负异常的驱动。青藏高原积雪减少也通过改变影响EAJ的热强迫发挥了调节作用。第二种模式主要与南海上空的异常反气旋和减弱的南移东太平洋海温异常有关，与热带中东部太平洋El Niño-like海温异常和北大西洋东部的冷海温异常密切相关。利用线性斜压模型和ECHAM5模型对上述机理进行了验证。

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引用次数: 0