The Atmospheric Infrared Sounder(AIRS)on the Aqua satellite,along with the MWTS/MWHS Synergy(TSHS)sounding system and Atmospheric Vertical Sounder System(VASS)on the Fengyun-3D(FY-3D)satellite,provide highquality data...The Atmospheric Infrared Sounder(AIRS)on the Aqua satellite,along with the MWTS/MWHS Synergy(TSHS)sounding system and Atmospheric Vertical Sounder System(VASS)on the Fengyun-3D(FY-3D)satellite,provide highquality data for studying Arctic temperature change.The generalized cold bias of AIRS is confirmed through horizontal comparisons with Arctic land radiosonde stations.VASS corrects the warm bias of TSHS by incorporating the Hyperspectral Infrared Atmospheric Sounder-I(HIRAS-I).Vertical comparisons demonstrate that AIRS,TSHS,and VASS offer excellent temperature detection from the top of the boundary layer to the lower stratosphere(800–100 h Pa).However,the overestimation and errors of stratospheric temperatures by TSHS and VASS increase with altitude(pressures below60 h Pa).Specifically,the warm bias trends at 0.06 K hPa^(-1),reaching 2.87 K and 2.92 K at 10 h Pa.Similarly,RMSE values trend at 0.05?K h Pa^(-1),reaching 3.62?K and 3.69?K at 10 h Pa.The low correlation(R≥0.65)of TSHS near 250 h Pa in summer is significantly improved in VASS(R≥0.78)after adding HIRAS-I.The high vertical resolution due to infrared hyperspectral resolution facilitates the detection of complex temperature junctions.The retrieval error of AIRS in the boundary layer increases with cloudiness,while VASS combines microwave and infrared channel data to reduce the impact of cloud cover.Assessing the Arctic applicability of these three satellite temperature profile products will facilitate their widespread use in the Arctic region,enhance accurate climate change monitoring,and further reveal the mechanisms of Arctic warming.展开更多
Atmospheric metal pollution is a significant environmental issue in China.Understanding the microscopic characteristics of metallic elements are crucial for investigating their sources and health effects,but this info...Atmospheric metal pollution is a significant environmental issue in China.Understanding the microscopic characteristics of metallic elements are crucial for investigating their sources and health effects,but this information is still limited.In this study,transmission electron microscopy(TEM)combined with bulk analysis method were employed to investigate the microscopic characteristics and mass concentrations of atmospheric metallic elements at a village site and an urban site located in North China Plain during wintertime.Our results reveal that the total mass concentrations of 16 metallic elements(including nine toxic heavy metallic elements)in PM_(2.5)were 3439.18±1101.24 ng/m^(3)(1129.6±376.85 ng/m^(3))at the village site and 3555.1±916.71 ng/m^(3)(1295.26±446.39 ng/m^(3))at urban site,accounting for 2.23%and 2.76%of PM_(2.5),respectively.We found that K,Ca,and Fe were the dominant elements,constituting over 75%of total metal mass.TEM analysis indicates that these metallic elements were mainly enriched in six types of individual particles,including K-rich,mineral,fly ash,Fe-rich,Zn-rich,and Pb-rich particles.Mineral particles were predominant in all individual metal particles at urban site,while K-rich particles became the dominant metal particles influenced by residential biomass burning at village site.Moreover,we found toxic metal particles(Fe-rich,Zn-rich,Pb-rich,and fly ash)presented smaller mean sizes(243 nm)in village air compared to urban air(337 nm),suggesting that metal particles in village air might pose a higher health risk to the residents.These results emphasize that atmospheric metal pollution in the village areas need more attentions in the future.展开更多
随着卫星遥感关键技术的突破,卫星光谱分辨率达到了分辨大气成分单个谱线的水平,研究人员开始了大量通道同时反演大气廓线和多种微量成分的研究。针对AIRS(Atmospheric Infrared Sounder)就红外高光谱资料反演大气水汽廓线的研究进展进...随着卫星遥感关键技术的突破,卫星光谱分辨率达到了分辨大气成分单个谱线的水平,研究人员开始了大量通道同时反演大气廓线和多种微量成分的研究。针对AIRS(Atmospheric Infrared Sounder)就红外高光谱资料反演大气水汽廓线的研究进展进行了评述,从训练数据、通道信息的提取及降维、反演算法和反演精度改进4个方面对反演晴空大气水汽廓线的研究现状进行了分析与讨论。AIRS资料反演大气水汽廓线的训练数据通常选用威斯康星大学提供的全球晴空反演训练样本集CIMSS(Cooperative Institute for Meteorological Satellite Studies,University of Wisconsin-Madison)和SARTA(Stand-Alone Radiative Transfer Algorithm)辐射传输模式模拟的亮温辐射值。归纳总结了2种通道信息的提取及降维方法:一是采用有效的方法来完成光谱信息压缩,对常用的主成分分析和独立分量分析方法进行了对比,认为独立分量分析更为可行。二是通道选择,即保留部分含有较多大气廓线信息量的通道,达到降维目的。在进行通道选择时要注意针对不同地区气候类型、下垫面、季节以及即时天气条件,选择不同的通道组合。介绍了3种反演算法:特征向量统计法、牛顿非线性迭代法和神经网络法。对比发现特征向量统计法简单易行,但精度不够理想;牛顿非线性迭代法精度虽高但计算耗时长,因此不适合业务使用;神经网络计算速度快、精度也能达到要求,具有很好的前景。对目前的几种样本分类方法及附加因子进行了对比分析,对反演算法精度的改进提出了一些有益的设想。最后对晴空辐射订正及云天大气水汽廓线反演进行了简要介绍,提出了该领域未来的一些研究方向。展开更多
本文利用中尺度非静力WRF(Weather Research Forecast,Version 3.4)模式,针对1013号"鲇鱼"台风个例,通过对红外高光谱AIRS(Atmospheric Infrared Sounder)资料经过基于空间梯度信息的质量控制之后同化进入模式,来评估新的质...本文利用中尺度非静力WRF(Weather Research Forecast,Version 3.4)模式,针对1013号"鲇鱼"台风个例,通过对红外高光谱AIRS(Atmospheric Infrared Sounder)资料经过基于空间梯度信息的质量控制之后同化进入模式,来评估新的质量控制方法对同化效果的影响以及对台风数值模拟的改善情况。研究结果发现,如果仅仅基于WRFDA(WRF Data Assimilation system,Version 3.4)模式自带的质量控制系统,将会有部分梯度距平值明显较大超过阈值的资料被同化进入模式,而这些可能受到"污染"且误差较大的资料同化进入模式必将会导致同化结果有较大误差,影响分析结果的质量。而对AIRS资料经过基于空间梯度信息质量控制之后再同化进入模式,确实可将梯度距平值大于阈值的"坏点"剔除掉,从而使初始场的描述更加准确,台风路径的模拟精度在一定程度上得到提高。综上可知,基于空间梯度信息的质量控制方法整体上对改善同化效果有较好的正效应,对台风的数值模拟也起到一定的促进作用。展开更多
基金supported by the National Key R&D Program of China(Grant Nos.2022YFC2807204 and 2022YFE0106700)the Basic Research Fund of the Chinese Academy of Meteorological Sciences(Grant Nos.2023Z004,2023Z015,and 2023Y012)。
文摘The Atmospheric Infrared Sounder(AIRS)on the Aqua satellite,along with the MWTS/MWHS Synergy(TSHS)sounding system and Atmospheric Vertical Sounder System(VASS)on the Fengyun-3D(FY-3D)satellite,provide highquality data for studying Arctic temperature change.The generalized cold bias of AIRS is confirmed through horizontal comparisons with Arctic land radiosonde stations.VASS corrects the warm bias of TSHS by incorporating the Hyperspectral Infrared Atmospheric Sounder-I(HIRAS-I).Vertical comparisons demonstrate that AIRS,TSHS,and VASS offer excellent temperature detection from the top of the boundary layer to the lower stratosphere(800–100 h Pa).However,the overestimation and errors of stratospheric temperatures by TSHS and VASS increase with altitude(pressures below60 h Pa).Specifically,the warm bias trends at 0.06 K hPa^(-1),reaching 2.87 K and 2.92 K at 10 h Pa.Similarly,RMSE values trend at 0.05?K h Pa^(-1),reaching 3.62?K and 3.69?K at 10 h Pa.The low correlation(R≥0.65)of TSHS near 250 h Pa in summer is significantly improved in VASS(R≥0.78)after adding HIRAS-I.The high vertical resolution due to infrared hyperspectral resolution facilitates the detection of complex temperature junctions.The retrieval error of AIRS in the boundary layer increases with cloudiness,while VASS combines microwave and infrared channel data to reduce the impact of cloud cover.Assessing the Arctic applicability of these three satellite temperature profile products will facilitate their widespread use in the Arctic region,enhance accurate climate change monitoring,and further reveal the mechanisms of Arctic warming.
基金supported by the National Natural Science Foundation of China(Nos.42307143,42307127,and 42307141)Shandong Provincial Natural Science Foundation(Nos.ZR2023QD151,ZR2024QD160,and ZR2023QD094)+2 种基金Zhejiang Province Basic Public Welfare Research Program Project(No.LGC22B050009)the Ph.D.Research Startup Foundation of Shandong University of Aeronautics(No.2022Y19)LAC/CMA(No.2023B10)。
文摘Atmospheric metal pollution is a significant environmental issue in China.Understanding the microscopic characteristics of metallic elements are crucial for investigating their sources and health effects,but this information is still limited.In this study,transmission electron microscopy(TEM)combined with bulk analysis method were employed to investigate the microscopic characteristics and mass concentrations of atmospheric metallic elements at a village site and an urban site located in North China Plain during wintertime.Our results reveal that the total mass concentrations of 16 metallic elements(including nine toxic heavy metallic elements)in PM_(2.5)were 3439.18±1101.24 ng/m^(3)(1129.6±376.85 ng/m^(3))at the village site and 3555.1±916.71 ng/m^(3)(1295.26±446.39 ng/m^(3))at urban site,accounting for 2.23%and 2.76%of PM_(2.5),respectively.We found that K,Ca,and Fe were the dominant elements,constituting over 75%of total metal mass.TEM analysis indicates that these metallic elements were mainly enriched in six types of individual particles,including K-rich,mineral,fly ash,Fe-rich,Zn-rich,and Pb-rich particles.Mineral particles were predominant in all individual metal particles at urban site,while K-rich particles became the dominant metal particles influenced by residential biomass burning at village site.Moreover,we found toxic metal particles(Fe-rich,Zn-rich,Pb-rich,and fly ash)presented smaller mean sizes(243 nm)in village air compared to urban air(337 nm),suggesting that metal particles in village air might pose a higher health risk to the residents.These results emphasize that atmospheric metal pollution in the village areas need more attentions in the future.
文摘随着卫星遥感关键技术的突破,卫星光谱分辨率达到了分辨大气成分单个谱线的水平,研究人员开始了大量通道同时反演大气廓线和多种微量成分的研究。针对AIRS(Atmospheric Infrared Sounder)就红外高光谱资料反演大气水汽廓线的研究进展进行了评述,从训练数据、通道信息的提取及降维、反演算法和反演精度改进4个方面对反演晴空大气水汽廓线的研究现状进行了分析与讨论。AIRS资料反演大气水汽廓线的训练数据通常选用威斯康星大学提供的全球晴空反演训练样本集CIMSS(Cooperative Institute for Meteorological Satellite Studies,University of Wisconsin-Madison)和SARTA(Stand-Alone Radiative Transfer Algorithm)辐射传输模式模拟的亮温辐射值。归纳总结了2种通道信息的提取及降维方法:一是采用有效的方法来完成光谱信息压缩,对常用的主成分分析和独立分量分析方法进行了对比,认为独立分量分析更为可行。二是通道选择,即保留部分含有较多大气廓线信息量的通道,达到降维目的。在进行通道选择时要注意针对不同地区气候类型、下垫面、季节以及即时天气条件,选择不同的通道组合。介绍了3种反演算法:特征向量统计法、牛顿非线性迭代法和神经网络法。对比发现特征向量统计法简单易行,但精度不够理想;牛顿非线性迭代法精度虽高但计算耗时长,因此不适合业务使用;神经网络计算速度快、精度也能达到要求,具有很好的前景。对目前的几种样本分类方法及附加因子进行了对比分析,对反演算法精度的改进提出了一些有益的设想。最后对晴空辐射订正及云天大气水汽廓线反演进行了简要介绍,提出了该领域未来的一些研究方向。
文摘本文利用中尺度非静力WRF(Weather Research Forecast,Version 3.4)模式,针对1013号"鲇鱼"台风个例,通过对红外高光谱AIRS(Atmospheric Infrared Sounder)资料经过基于空间梯度信息的质量控制之后同化进入模式,来评估新的质量控制方法对同化效果的影响以及对台风数值模拟的改善情况。研究结果发现,如果仅仅基于WRFDA(WRF Data Assimilation system,Version 3.4)模式自带的质量控制系统,将会有部分梯度距平值明显较大超过阈值的资料被同化进入模式,而这些可能受到"污染"且误差较大的资料同化进入模式必将会导致同化结果有较大误差,影响分析结果的质量。而对AIRS资料经过基于空间梯度信息质量控制之后再同化进入模式,确实可将梯度距平值大于阈值的"坏点"剔除掉,从而使初始场的描述更加准确,台风路径的模拟精度在一定程度上得到提高。综上可知,基于空间梯度信息的质量控制方法整体上对改善同化效果有较好的正效应,对台风的数值模拟也起到一定的促进作用。
