Atmospheric Research最新文献_第3页

Quantifying the influence of dominant factors on the long-term sandstorm weather - A case study in the Yellow River Basin during 2000–2021 量化主导因素对长期风沙天气的影响--2000-2021 年黄河流域案例研究

IF 4.5 2区地球科学 Q1 METEOROLOGY & ATMOSPHERIC SCIENCES

Atmospheric Research

Pub Date : 2024-10-03 DOI: 10.1016/j.atmosres.2024.107717

Sandstorm is a disastrous weather phenomenon that often occurs in arid and semi-arid areas, endangering the ecological environment and affecting people's lives and property safety seriously. Since the 21st century, the sandstorm weather in the Yellow River Basin has ameliorated obviously. However, the causes of the long-term trends in sandstorms during 21st century were still unknown. In this study, fifteen influencing factors from five aspects: ecology, meteorology, hydrology, geography and man-made were selected to comprehensively analyze the driving mechanism of sandstorm activities in the Yellow River Basin since the 21st century, and the effect of each influencing factor on sandstorm weather was quantified. The results indicated that ecological, meteorological and geographical factors had dominant impacts on the spatio-temporal variation of sandstorms during 2000–2021, while hydrological and human factors played little role in the long-term variation of sandstorms. Sandstorms frequently occurred in semi-desert or grassland or non-high vegetation covered areas in spring. Vegetation coverage, precipitation, surface pressure, surface roughness, and soil moisture content were negatively correlated with sandstorms, while wind speed, friction velocity, evaporation, and soil temperature were positively correlated with sandstorms. Precipitation, runoff, evaporation, soil moisture content, soil temperature, and surface temperature indirectly acted on normalized brightness temperature dust index (NBTDI) and sandstorms by changing soil texture. Normalized Vegetation Index (NDVI) had direct negative effects on NBTDI, while wind speed 10 m (WS10m), slope of sub-gridscale orography (SOSGO), and forecast surface roughness (FSR) had direct positive effects on NBTDI. This study comprehensively revealed the dominant factors and their driving mechanism of sandstorm weather in the Yellow River Basin since the 21st century, which had practical application value for the prevention of sandstorms.

沙尘暴是干旱半干旱地区经常出现的灾害性天气现象，严重危害生态环境，影响人民生命财产安全。进入 21 世纪以来，黄河流域风沙天气明显好转。然而，21 世纪沙尘暴长期趋势的成因尚不清楚。本研究从生态、气象、水文、地理和人为五个方面选取了 15 个影响因子，全面分析了 21 世纪以来黄河流域沙尘暴活动的驱动机制，并量化了各影响因子对沙尘暴天气的影响。结果表明，生态、气象和地理因素对 2000-2021 年沙尘暴的时空变化具有主导影响，而水文和人为因素对沙尘暴的长期变化作用不大。春季沙尘暴多发生在半荒漠或草原或植被覆盖率不高的地区。植被覆盖率、降水量、地表压力、地表粗糙度和土壤含水量与沙尘暴呈负相关，而风速、摩擦速度、蒸发量和土壤温度与沙尘暴呈正相关。降水、径流、蒸发、土壤水分含量、土壤温度和地表温度通过改变土壤质地间接影响归一化亮度温度沙尘指数（NBTDI）和沙尘暴。归一化植被指数（NDVI）对归一化亮度温尘指数（NBTDI）有直接的负面影响，而 10 米风速（WS10m）、子网格尺度地形坡度（SOSGO）和预报表面粗糙度（FSR）对归一化亮度温尘指数（NBTDI）有直接的正面影响。该研究全面揭示了 21 世纪以来黄河流域沙尘暴天气的主导因子及其驱动机制，对预防沙尘暴天气具有实际应用价值。

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引用次数: 0

The contribution of Arabian Sea warming to decreasing summer precipitation in the northern Greater Mekong Subregion 阿拉伯海变暖对大湄公河次区域北部夏季降水量减少的影响

IF 4.5 2区地球科学 Q1 METEOROLOGY & ATMOSPHERIC SCIENCES

Atmospheric Research

Pub Date : 2024-10-02 DOI: 10.1016/j.atmosres.2024.107714

The Greater Mekong Subregion (GMS) is one of the world's most important agricultural regions. Over recent decades, the declining trend in precipitation has caused more frequent droughts over the northern plateau of the GMS, and this has led to a significant reduction in agricultural productivity. These drought events can also affect agriculture within the middle and lower parts of the Mekong River basin. To reveal the main causes of the decline in precipitation, this study investigates interdecadal variations in summer precipitation over the northern GMS during 1979–2022. Results indicate that summer conditions over the northern GMS entered a relatively dry period after the late 1990s. The interdecadal decrease in summer precipitation is closely associated with the warming of the northern Arabian Sea (AS), which induces a cyclonic anomaly that enhances local precipitation and associated diabatic heating. The anomalous diabatic heating induces a downstream Rossby wave train that intensifies the circumglobal teleconnection (CGT) pattern and causes the South Asian high (SAH) to extend farther southeastwards. The southeastward-displaced SAH induces easterly anomalies over the northern Bay of Bengal (BOB) that weaken the Indian summer monsoon (ISM) southwesterly flows and reduce moisture transport from the northern BOB to the northern GMS. The southeastward displacement of the SAH also causes anomalous descent over the northern GMS. Both conditions result in reduced precipitation over the northern GMS. Numerical experiments substantiate the proposed modulating role of AS warming in the interdecadal decrease in summer precipitation over the northern GMS.

大湄公河次区域（GMS）是世界上最重要的农业区之一。近几十年来，由于降水量呈下降趋势，大湄公河次区域北部高原的干旱更加频繁，导致农业生产率显著下降。这些干旱事件也会影响湄公河流域中下游地区的农业。为了揭示降水量下降的主要原因，本研究调查了 1979-2022 年间大湄公河次区域北部夏季降水量的年代际变化。研究结果表明，自 20 世纪 90 年代末以来，大湄公河流域北部的夏季气候进入了一个相对干旱的时期。夏季降水量的年代际减少与阿拉伯海（AS）北部的变暖密切相关，它引起了气旋异常，从而增强了局地降水量和相关的二重加热。异常的二重加热诱发了下游的罗斯比波列，从而加强了环全球遥联系（CGT）模式，并导致南亚高纬度（SAH）向东南方向延伸得更远。向东南位移的南亚高气压在孟加拉湾（BOB）北部上空引起偏东异常，削弱了印度夏季季风（ISM）的西南气流，减少了从孟加拉湾北部向大湄公河次区域北部的水汽输送。SAH 的东南位移也导致 GMS 北部出现异常下降。这两种情况都导致 GMS 北部降水量减少。数值实验证实了所提出的 AS 变暖和 GMS 北部夏季降水量跨年代减少的调节作用。

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引用次数: 0

The distinct roles of the Stratospheric Polar Vortex during the initiation and intensification stages of the 2016 East Asian Cold Air Outbreak 平流层极地涡旋在 2016 年东亚冷空气爆发的启动和加强阶段的独特作用

IF 4.5 2区地球科学 Q1 METEOROLOGY & ATMOSPHERIC SCIENCES

Atmospheric Research

Pub Date : 2024-10-02 DOI: 10.1016/j.atmosres.2024.107713

Using ERA-Interim reanalysis data and ensemble forecasts from the Global Ensemble Forecast System (GEFS), we explore the roles of the Arctic stratospheric polar vortex throughout the life cycle of the 2016 East Asian cold air outbreak (CAO). Our results reveal the distinct roles of the stratosphere in the initiation and intensification stages of this CAO. The occurrence of this CAO was directly related to an exceptionally strong Ural blocking ridge that advected cold air mass toward East Asia. Notably, the strengthening of Ural blocking is largely influenced by the behavior of the stratospheric polar vortex. Specifically, the contraction of the polar vortex toward the western Urals paved the way for reflecting planetary waves originating from the North Atlantic via changing the buoyancy frequency just above the tropopause. The reflected waves converged over the western Urals and acted to strengthen Ural blocking that in turn affected this CAO. Subsequently, an elongation of the polar vortex toward East Asia was observed, leading to a significant descent of the tropopause over East Asia. According to the invertibility theory of potential vorticity, the descending tropopause likely induced a cyclonic anomaly over East Asia, further contributing to the intensification of this CAO. However, the impact of this cyclonic anomaly induced by the polar vortex elongation is relatively limited compared to the influence of Ural blocking. In summary, our study highlights that the geometry of the polar vortex, rather than its strength, is crucial in understanding the stratospheric impacts on the 2016 East Asian CAO.

利用ERA-Interim再分析数据和全球集合预报系统（GEFS）的集合预报，我们探讨了北极平流层极地涡旋在2016年东亚冷空气爆发（CAO）整个生命周期中的作用。我们的研究结果揭示了平流层在此次CAO的起始和加强阶段所扮演的不同角色。此次CAO的发生与一个异常强大的乌拉尔阻挡脊直接相关，该阻挡脊将冷气团向东亚地区推进。值得注意的是，乌拉尔阻塞的加强在很大程度上受到平流层极地涡旋行为的影响。具体来说，极地涡旋向乌拉尔西部收缩，通过改变对流层顶上方的浮力频率，为反射来自北大西洋的行星波铺平了道路。反射波汇聚到乌拉尔西部上空，加强了乌拉尔阻塞，进而影响了这一 CAO。随后，极地涡旋向东亚方向延伸，导致东亚上空的对流层顶显著下降。根据潜在涡度的可逆性理论，对流层顶的下降很可能在东亚上空诱发气旋异常，进一步加剧了这次 CAO 的强度。然而，与乌拉尔阻塞的影响相比，极地涡旋伸长引起的气旋异常的影响相对有限。总之，我们的研究突出表明，极地涡旋的几何形状而非其强度对于理解平流层对 2016 年东亚 CAO 的影响至关重要。

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引用次数: 0

Characteristics of extreme hourly precipitation induced by tropical cyclones in Zhejiang, China: A comparative analysis based on two different datasets 中国浙江热带气旋引发的极端小时降水特征：基于两种不同数据集的对比分析

IF 4.5 2区地球科学 Q1 METEOROLOGY & ATMOSPHERIC SCIENCES

Atmospheric Research

Pub Date : 2024-09-30 DOI: 10.1016/j.atmosres.2024.107712

This study investigates the characteristics of tropical cyclones (TCs) that cause extreme hourly precipitation (EXHP) in Zhejiang, China, using datasets from 67 national stations (Con-ST) and 1551 surface stations (All-ST), spanning 1973–2020 and 2011–2020, respectively. Our analysis revealed notable variations in the EXHP caused by individual TCs. The top 10 % of TCs contributed 37.2–38 % of the total TC-induced EXHP amount, while the bottom 50 % only accounted for 5.8–22.7 %. Using sparse stations may overestimate the impact of TCs causing EXHP in the lower to middle rankings. Long-term trend analysis suggested a consistent increase in TC-induced EXHP despite a decreasing trend in the number of TCs affecting Zhejiang. High-value EXHP centers tended to be concentrated in mountainous areas within 0–50 km from the coastline, where Con-ST stations are sparse and can significantly underestimate EXHP. The maximum amount of EXHP per TC increased logarithmically with the number of observation stations. In Zhejiang, EXHP predominantly occurred northeast of the TC centers (50.4–61.7 %) and within 500 km from the TC center (69.5–81.5 %). High-frequency EXHP centers exhibited a clockwise rotation with increasing distance from the TC center–a pattern resembling a “spiral rainband.” A key area where most EXHP in Zhejiang occurred when TC centers remained within this area was identified. The TC intensity within the key area was a key factor influencing EXHP occurrence in Zhejiang, whereas the duration of TC center residence within the key area and the distance of its movement were crucial predictors of significant EXHP occurrence. The analysis of large-scale environmental fields revealed that high-EXHP TCs are characterized by strong upper-level divergence, intense upward motion, and an expanded subtropical high. The southeasterly steering airflow drives these TCs northwestward, prolonging their impact on Zhejiang and resulting in significant moisture accumulation and EXHP.

本研究利用来自 67 个国家站（Con-ST）和 1551 个地面站（All-ST）的数据集，分别研究了 1973-2020 年和 2011-2020 年导致中国浙江极端小时降水量（EXHP）的热带气旋（TC）的特征。我们的分析表明，单个热带气旋造成的 EXHP 有显著差异。前10%的TC占TC引起的EXHP总量的37.2-38%，而后50%的TC仅占5.8-22.7%。使用稀疏站点可能会高估TC对中低层EXHP的影响。长期趋势分析表明，尽管影响浙江的TC数量呈减少趋势，但TC引起的EXHP持续增加。高值的EXHP中心往往集中在距离海岸线0-50公里内的山区，而这些地区的Con-ST站点稀少，会大大低估EXHP。每个 TC 的最大 EXHP 量随观测站点数量的增加而呈对数增长。在浙江，EXHP主要出现在TC中心的东北部（50.4-61.7%）和距TC中心500公里以内（69.5-81.5%）。高频EXHP中心呈现出顺时针旋转的趋势，与TC中心的距离越来越远，这种模式类似于 "螺旋雨带"。当TC中心停留在这一区域内时，浙江的大部分EXHP发生在这一关键区域。关键区域内的TC强度是影响浙江EXHP发生的关键因素，而TC中心在关键区域内停留的时间及其移动的距离则是预测EXHP显著发生的关键因素。大尺度环境场分析表明，高EXHP TC具有强烈的高层辐合、强烈的上升运动和副热带高压扩张的特征。东南方向的转向气流推动这些TC向西北方向移动，延长了对浙江的影响时间，导致大量水汽积聚和EXHP的发生。

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引用次数: 0

Enhanced interannual variability of the May North Atlantic Oscillation and its impact on summer sea ice in the North Atlantic after the mid-2000s 2000 年代中期以后北大西洋五月涛动的年际变率增强及其对北大西洋夏季海冰的影响

IF 4.5 2区地球科学 Q1 METEOROLOGY & ATMOSPHERIC SCIENCES

Atmospheric Research

Pub Date : 2024-09-30 DOI: 10.1016/j.atmosres.2024.107703

Based on data diagnosis and numerical experiments, this study investigated the changes in the interannual properties of the May North Atlantic Oscillation (NAO) and their impact on summer (June–July) sea ice in the North Atlantic during 1979–2021. Results showed statistically significant increase in the interannual variability of the May NAO after the mid-2000s, which had remarkably enhanced impact on summer sea ice in the eastern Hudson Bay (EHB) and the western Labrador Sea (WLS). During 2005–2021, corresponding to a positive phase of the May NAO, anomalous surface westerly or northwesterly winds prevailed over the Hudson Bay and Labrador Sea in May. This led to statistically significant increase in sea ice in both the EHB and the WLS in May via dynamic processes (favoring southeastward movement of the sea ice) and thermal processes (changing surface turbulent heating and shortwave radiation). In comparison with the situation in May, the increase in sea ice in the EHB developed further during summer mainly via thermal processes (positive feedback between the increased sea ice and shortwave radiation). In contrast, amplitude of the increased sea ice in the WLS was comparable between May and summer. Dynamic processes (southeastward movement of sea ice), which was induced by a barotropic anomalous high in the troposphere centered over the Labrador Peninsula, favored the increase in sea ice in summer in the WLS. The tripole sea surface temperature anomalies in the North Atlantic and increased snowpack on the Labrador Peninsula in May, triggered by the positive phase of the May NAO, played an important role in the formation of the anomalous high. During 1979–2004, the surface wind, snowpack, and tripole sea surface temperature anomalies in May, triggered by the May NAO, were relatively weak, leading to statistically insignificant changes in summer sea ice in the EHB and WLS.

本研究基于数据诊断和数值实验，研究了1979-2021年期间北大西洋5月涛动（NAO）的年际特性变化及其对北大西洋夏季（6-7月）海冰的影响。结果表明，2000 年代中期以后，5 月北大西洋涛动的年际变率在统计上明显增加，对哈德逊湾东部和拉布拉多海西部夏季海冰的影响显著增强。在 2005-2021 年期间，与 5 月 NAO 正相位相对应，哈得逊湾和拉布拉多海 5 月份盛行异常的表面西风或西北风。通过动力过程（有利于海冰向东南移动）和热力过程（改变表面湍流加热和短波辐射），这导致 EHB 和 WLS 的海冰在 5 月份出现统计意义上的显著增加。与五月份的情况相比，夏季 EHB 海冰的增加主要通过热过程（增加的海冰与短波辐射之间的正反馈）进一步发展。与此相反，5 月和夏季，WLS 海冰增加的幅度相当。以拉布拉多半岛为中心的对流层气压各向异性异常高气压诱发的动力过程（海冰向东南移动）有利于夏季西低海区海冰的增加。北大西洋的三极海面温度异常和拉布拉多半岛 5 月份积雪的增加（由 5 月份北大西洋环流正相位引发）在异常高点的形成过程中发挥了重要作用。在1979-2004年期间，5月NAO引发的表面风、积雪和5月三极海面温度异常相对较弱，导致EHB和WLS夏季海冰的变化在统计上不显著。

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引用次数: 0

Optimization of snow-related processes in Noah-MP land surface model over the mid-latitudes of Asian region 优化亚洲中纬度地区诺亚-MP 陆面模式中与雪有关的过程

IF 4.5 2区地球科学 Q1 METEOROLOGY & ATMOSPHERIC SCIENCES

Atmospheric Research

Pub Date : 2024-09-29 DOI: 10.1016/j.atmosres.2024.107711

Snow plays a critical role in modulating surface energy, water cycles, and climate prediction. Optimizing snow-related parameterizations can enhance the model behaviors in simulating snow-related physical processes and reduce the cold bias observed in winter climate simulations in the Northern Hemisphere. In this study, the topographic complexity and wind speed were incorporated into the parameterization of the snow cover fraction (SCF) and newly fallen snow density (SFD) respectively within the Noah with multi-parameterization (Noah-MP) LSM to optimize the simulation of snow-related processes in the mid-latitude regions of East Asia. A control simulation and three sensitivity experiments were conducted to investigate and quantify the effects of topographic complexity and wind speed on the simulation of snow-related processes and land surface temperature (LST) against MODIS products. The results showed that modifications to the two schemes effectively mitigated the overestimation of snow cover and albedo, and alleviated cold biases in the most of study area. The influence of SFD scheme considering wind speed was more pronounced in regions with more snowfall and higher wind speed, while the SCF scheme considering topographic complexity showed a more widespread effect. The combination of these two modified schemes yielded the best performance. The mean biases of SCF, albedo, and LST over the entire study region with both modified schemes were reduced by 0.126 (∼63 %), 0.044 (∼41 %), and 0.584 °C (∼18 %), respectively. Their RMSEs were reduced by 0.119 (∼36 %), 0.036 (∼22 %), and 0.489 °C (∼10 %), respectively. This study highlights the importance of wind conditions and topographic complexity in the simulations of snow-related characteristics over the mid-latitudes of Asian region.

雪在调节地表能量、水循环和气候预测方面起着至关重要的作用。优化与雪相关的参数可以增强模型在模拟与雪相关的物理过程时的表现，并减少在北半球冬季气候模拟中观察到的寒冷偏差。本研究将地形复杂性和风速分别纳入 Noah 多参数化（Noah-MP）LSM 的积雪覆盖率（SCF）和新降雪密度（SFD）参数化，以优化东亚中纬度地区与雪相关过程的模拟。针对 MODIS 产品进行了一次对照模拟和三次敏感性实验，以研究和量化地形复杂性和风速对模拟雪相关过程和地表温度（LST）的影响。结果表明，对两种方案的修改有效地缓解了对雪覆盖和反照率的高估，并减轻了大部分研究区域的冷偏差。考虑风速的 SFD 方案在降雪较多、风速较高的地区影响更为明显，而考虑地形复杂性的 SCF 方案的影响更为广泛。这两种改进方案的组合产生了最佳性能。采用这两种改进方案后，整个研究区域的 SCF、反照率和 LST 平均偏差分别减少了 0.126（∼63%）、0.044（∼41%）和 0.584 ℃（∼18%）。它们的均方根误差分别降低了 0.119 (∼36 %)、0.036 (∼22 %) 和 0.489 °C (∼10 %)。这项研究强调了风况和地形复杂性在模拟亚洲中纬度地区雪相关特征中的重要性。

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引用次数: 0

Performance assessment of multi-source GNSS radio occultation from COSMIC-2, MetOp-B/C, FY-3D/E, Spire and PlanetiQ over China 来自 COSMIC-2、MetOp-B/C、FY-3D/E、Spire 和 PlanetiQ 的中国上空多源全球导航卫星系统无线电掩星性能评估

IF 4.5 2区地球科学 Q1 METEOROLOGY & ATMOSPHERIC SCIENCES

Atmospheric Research

Pub Date : 2024-09-28 DOI: 10.1016/j.atmosres.2024.107704

Global Navigation Satellite System (GNSS) radio occultation (RO) is one of the most crucial observations in atmospheric and climate science. GNSS RO globally produces accurate and long-term stable vertical profiles for essential climate variables with high vertical resolution in all weather conditions. RO measurements offer global coverage but may be limited for specific regions. Currently, various RO satellite constellation programs have been developed by nations and companies, and the growing quantity of RO observations can contribute not only globally but also has the potential to benefit specific regions, such as China. To investigate the potential of RO observation in China, the performance of five operational RO measurements from COSMIC-2, MetOp-B/C, FY-3D/E, Spire and PlanetiQ on data coverage capabilities and quality are assessed by comparing with ERA5 and radiosonde over China. The results of data coverage showed that all RO missions can acquire extensive coverage over China with effective low-altitude penetration capability, whereas MetOp-B/C exhibits some gaps in local time coverage. The results of data quality confirmed that commercial Spire and PlanetiQ are comparable to those of national-led COSMIC-2, MetOp-B/C and FY3D/E, even though Spire exhibited a lower signal-to-noise ratio (SNR). The mean bending angle and refractivity relative differences of all RO measurements are within ±0.53/1.30 % and ± 0.54/0.28 % (with respect to ERA5/radiosonde) in the altitude range of 5 to 35 km, respectively, and the corresponding relative standard deviations (SD) are less than 2.20/6.99 % and 1.35/1.56 %, respectively. Mean temperature and specific humidity differences of all RO measurements are within ±0.18/0.22 K and ± 0.08/0.22 g/kg, respectively, from the near-surface to 12 km, with SD of less than 1.26/1.67 K and 0.84/0.91 g/kg. Among the five RO missions, FY-3D/E exhibits larger errors in refractivity, temperature and specific humidity. The RO profiles derived from GPS, GLONASS, BeiDou and Galileo show comparable quality at the altitudes below 35 km. These results can help users further understand the capabilities and performance of these RO observations and indicate the application potential of numerous RO profiles from multi-source RO measurements, which is anticipated to enhance numerical weather predictions for China.

全球导航卫星系统（GNSS）无线电掩星（RO）是大气和气候科学中最重要的观测手段之一。全球导航卫星系统的射电掩星在全球范围内为基本气候变量提供准确和长期稳定的垂直剖面图，在所有天气条件下都具有很高的垂直分辨率。RO 测量可覆盖全球，但对特定区域可能有限。目前，各国和各公司已经开发了各种 RO 卫星星座计划，RO 观测的数量不断增加，不仅能为全球做出贡献，而且有可能使中国等特定地区受益。为了研究中国 RO 观测的潜力，通过与 ERA5 和中国上空的无线电探空仪进行比较，评估了 COSMIC-2、MetOp-B/C、FY-3D/E、Spire 和 PlanetiQ 五种运行 RO 测量在数据覆盖能力和质量方面的性能。数据覆盖结果表明，所有 RO 任务都能获得中国上空的广泛覆盖，并具有有效的低空穿透能力，而 MetOp-B/C 在本地时间覆盖方面存在一些差距。数据质量结果表明，商用 Spire 和 PlanetiQ 与国家主导的 COSMIC-2、MetOp-B/C 和 FY3D/E 的数据质量相当，尽管 Spire 的信噪比（SNR）较低。在 5 至 35 千米高度范围内，所有 RO 测量的平均弯曲角和折射率相对差异分别在 ±0.53/1.30 % 和 ±0.54/0.28 %（相对于 ERA5/无线电探空仪）以内，相应的相对标准偏差（SD）分别小于 2.20/6.99 % 和 1.35/1.56 %。从近地面到 12 千米，所有 RO 测量的平均温差和比湿差分别在 ±0.18/0.22 K 和 ±0.08/0.22 g/kg 范围内，SD 分别小于 1.26/1.67 K 和 0.84/0.91 g/kg。在五个 RO 任务中，FY-3D/E 在折射率、温度和比湿方面的误差较大。从 GPS、GLONASS、BeiDou 和 Galileo 导出的 RO 曲线在 35 公里以下的高度显示出相似的质量。这些结果有助于用户进一步了解这些RO观测的能力和性能，并显示了从多源RO测量中获得的大量RO剖面的应用潜力，预计这将加强对中国的数值天气预报。

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引用次数: 0

Impacts of meteorology and mixing height on radioactive and stable aerosols in Bratislava, Slovakia 气象和混合高度对斯洛伐克布拉迪斯拉发放射性和稳定气溶胶的影响

IF 4.5 2区地球科学 Q1 METEOROLOGY & ATMOSPHERIC SCIENCES

Atmospheric Research

Pub Date : 2024-09-28 DOI: 10.1016/j.atmosres.2024.107710

This study investigated the variability of radioactive and stable aerosols (⁷Be, ²¹⁰Pb, ¹³⁷Cs, ⁴⁰K, PM10, and PM2.5) in relation to mixing layer height (MLH) based on outdoor radon and meteorological factors in Bratislava, Slovakia from 2017 to 2021. Aerosol concentrations exhibit distinct seasonal patterns, with higher ⁷Be concentrations in summer and lower in winter, while ¹³⁷Cs, ⁴⁰K, ²¹⁰Pb, PM10 and PM2.5 showed almost the opposite trends. Different statistical techniques, including Pearson's correlation analysis, multiple regression analysis (MRA), and canonical correlation analysis (CCA), were employed to elucidate the intricate relationships between aerosol concentrations, MLH, and meteorological parameters. The MRA identified a significant correlation between aerosol variability and specific predictors, while the CCA highlighted the differential influence of MLH and meteorological parameters on aerosol concentrations. The analysis revealed that temperature, MLH, and relative humidity are the primary factors influencing aerosol concentrations, underscoring their pivotal role in environmental dynamics.

本研究根据斯洛伐克布拉迪斯拉发的室外氡和气象因素，调查了 2017 年至 2021 年期间放射性和稳定气溶胶（7Be、210Pb、137Cs、40K、PM10 和 PM2.5）与混合层高度（MLH）的变化关系。气溶胶浓度呈现出明显的季节性特征，7Be浓度夏季较高，冬季较低，而137Cs、40K、210Pb、PM10和PM2.5则呈现出几乎相反的趋势。研究人员采用了不同的统计技术，包括皮尔逊相关分析、多元回归分析和典型相关分析，以阐明气溶胶浓度、MLH 和气象参数之间错综复杂的关系。多元回归分析确定了气溶胶变异性与特定预测因子之间的显著相关性，而典型相关分析则强调了 MLH 和气象参数对气溶胶浓度的不同影响。分析结果表明，温度、空气湿度和相对湿度是影响气溶胶浓度的主要因素，突出了它们在环境动态中的关键作用。

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引用次数: 0

Changes in temperature and precipitation extremes over Western Asia: A regional ensemble from CMIP6 西亚极端气温和降水的变化：CMIP6 的区域集合

IF 4.5 2区地球科学 Q1 METEOROLOGY & ATMOSPHERIC SCIENCES

Atmospheric Research

Pub Date : 2024-09-28 DOI: 10.1016/j.atmosres.2024.107707

This study investigates the impacts of climate change on temperature and precipitation extremes in eight West Asian countries (Iran, Afghanistan, Pakistan, Turkmenistan, Azerbaijan, Armenia, Turkey, and Iraq) using a regional ensemble of CMIP6 models. Ten models were evaluated based on their performance in simulating historical temperature and precipitation using the KGE index. Four climate extreme indices (T_max, P_max, TX90p and R95p) were employed to assess changes in temperature and precipitation extremes in the study area. The analysis of climate extremes reveals significant projected changes. T_max is expected to increase in all countries, with the most pronounced rise anticipated in Turkmenistan, where T_max in the main part of the country is projected to increase by more than 5 °C under the SSP585. Projections for P_max show a more nuanced picture. Pakistan is expected to experience the highest overall P_max. TX90p is projected to increase in all countries, indicating a rise in the frequency of extreme heat events. Pakistan is expected to experience the most significant increase in TX90p, reaching up to 36.1 % under the SSP585 (FF) scenario by 2074, followed by Iran and Afghanistan. R95p does not show a clear future trend. Pakistan is anticipated to see the highest increase in R95p, reaching up to 15.2 mm under the SSP585 scenario by 2074, while Turkey might experience a decrease of up to 7.8 mm under the SSP245 scenario. These findings highlight the diverse and concerning impacts of climate change on temperature and precipitation extremes across West Asia. The projected increase in T_max, TX90p and potential shifts in precipitation patterns pose significant challenges for the region. This study emphasizes the need for region-specific adaptation strategies to address the multifaceted challenges of climate change in West Asia.

本研究利用 CMIP6 模型的区域集合，调查了气候变化对八个西亚国家（伊朗、阿富汗、巴基斯坦、土库曼斯坦、阿塞拜疆、亚美尼亚、土耳其和伊拉克）极端气温和降水的影响。根据使用 KGE 指数模拟历史气温和降水的性能，对 10 个模式进行了评估。采用了四个气候极端指数（Tmax、Pmax、TX90p 和 R95p）来评估研究地区极端气温和极端降水的变化。对极端气候的分析表明，预测变化显著。预计所有国家的 Tmax 都将上升，其中土库曼斯坦的上升最为明显，根据 SSP585，该国主要地区的 Tmax 预计将上升 5 ℃ 以上。对最高气温的预测则显示出更微妙的情况。巴基斯坦的总体 Pmax 预计最高。预计所有国家的 TX90p 都将增加，这表明极端高温事件的频率将上升。巴基斯坦的 TX90p 预计将出现最显著的增长，在 SSP585（FF）情景下，到 2074 年将达到 36.1%，其次是伊朗和阿富汗。R95p 未显示出明确的未来趋势。在 SSP585 情景下，巴基斯坦的 R95p 预计将出现最高增幅，到 2074 年将达到 15.2 毫米，而在 SSP245 情景下，土耳其的 R95p 可能会减少 7.8 毫米。这些发现凸显了气候变化对整个西亚地区极端气温和降水的不同影响。预计的最高气温、TX90p 的增加以及降水模式的潜在变化对该地区构成了重大挑战。这项研究强调，有必要制定针对具体地区的适应战略，以应对西亚地区气候变化带来的多方面挑战。

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引用次数: 0

Air pollutant prediction based on a attention mechanism model of the Yangtze River Delta region in frequent heatwaves 基于热浪频发时长江三角洲地区注意机制模型的空气污染物预测

IF 4.5 2区地球科学 Q1 METEOROLOGY & ATMOSPHERIC SCIENCES

Atmospheric Research

Pub Date : 2024-09-27 DOI: 10.1016/j.atmosres.2024.107701

Heatwaves pose significant threats to urban environments, affecting both ecological systems and public health, primarily through the exacerbation of air pollution. Accurate prediction of air pollutant concentrations during heatwave periods is crucial for authorities to develop timely prevention and control strategies. Thus, we developed the 1D-CNN-BiLSTM-attention model, specifically designed to account for the unique data characteristics associated with heatwave conditions. Our model leverages an attention mechanism to enhance its ability to learn and predict air pollutant behavior during heatwaves. Across six scenario-based experiments, the model demonstrated high predictive accuracy, achieving a MAPE of 2.93 %. The model integrates meteorological indicators such as temperature, humidity, wind speed, cloud cover, and precipitation, extending its predictive capability across a spatial range of 150 km. In experiments testing the model's applicability to three typical city types in the Yangtze River Delta region, the results confirmed its effectiveness in predicting air pollutants. These findings highlight the model's usefulness for studying air pollution during urban heatwave periods on a regional scale, demonstrating its robustness and reliability under varying weather conditions.

热浪对城市环境构成重大威胁，主要通过加剧空气污染影响生态系统和公众健康。准确预测热浪期间的空气污染物浓度对于有关部门制定及时的预防和控制策略至关重要。因此，我们开发了 1D-CNN-BiLSTM-attention 模型，专门用于考虑与热浪条件相关的独特数据特征。我们的模型利用注意力机制来增强其学习和预测热浪期间空气污染物行为的能力。在六个基于场景的实验中，该模型表现出很高的预测准确性，MAPE 为 2.93%。该模型整合了温度、湿度、风速、云层和降水等气象指标，将其预测能力扩展到 150 千米的空间范围。在对长三角地区三个典型城市类型的适用性实验中，结果证实了该模型在预测空气污染物方面的有效性。这些研究结果凸显了该模型在区域范围内研究城市热浪期空气污染的实用性，证明了其在不同天气条件下的稳健性和可靠性。

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引用次数: 0