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Particuology 2015年第3期13卷 41-51页

作者： Jian-Bin Wu Jianming Xu Mariusz Pagowski Fuhai Geng Songqiang Gu Guangqiang Zhou Ying Xie Zhongqi Yu Shanghai Meteorological Service noaa Earth System Research Laboratory(esrl)

This study focuses on the importance of initial conditions to air-quality predictions. We ran assimilation experiments using the WRF-Chem model and grid-point statistical interpolation （GSI）, for a 9-day severe particulate matter pollution event that occurred in Shanghai in December 2013. In this application, GSI used a three-dimensional variational approach to assimilate ground-based PM2.s observations into the chemical model, to obtain initial fields for the aerosol species. In our results, data assimilation significantly reduced the errors when compared to a simulation without assimilation, and improved forecasts of PM2.5 concentrations. Despite a drop in skill directly after the assimilation, a positive effect was present in forecasts for at least 12-2413, and there was a slight improvement in the 48-h forecasts. In addition to performing well in Shanghai, the verification statistics for this assimilation experiment are encouraging for most of the surface stations in China.

关键词： Data assimilationAerosol pollutionInitial conditionForecastingPM2.5

Influence of the Atlantic Multidecadal Oscillation on the Winter Climate of East China

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Advances in Atmospheric Sciences 2007年第1期24卷 126-135页

作者：李双林 Gary T.BATES Nansen-Zhu International Research Centre Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029 NOAA ESRL-CIRES Climate Diagnostics CenterUniversity of ColoradoBoulderColorado noaa esrl-CIRES Climate Diagnostics Center University of ColoradoBoulderColorado

The Atlantic Multidecadal Oscillation （AMO）, the multidecadal variation of North Atlantic sea surface temperature （SST）, exhibits an oscillation with a period of 65-80 years and an amplitude of 0.4℃. Observational composite analyses reveal that the warm phase AMO is linked to warmer winters in East China, with enhanced precipitation in the north of this region and reduced precipitation in the south, on multidecadal time scales. The pattern is reversed during the cold phase AMO. Whether the AMO acts as a forcing of the multidecadal winter climate of East China is explored by investigating the atmospheric response to warm AMO SST anomalies in a large ensemble of atmospheric general circulation model （AGCM） experiments. The results from three AGCMs are consistent and suggest that the AMO warmth favors warmer winters in East China. This influence is realized through inducing negative surface air pressure anomalies in the hemispheric-wide domain extending from the midlatitude North Atlantic to midlatitude Eurasia. These negative surface anomalies favor the weakening of the Mongolian Cold High, and thus induce a weaker East Asian Winter Monsoon.

关键词： Atlantic Multidccadal Oscillation winter climate East China

The 2022 Extreme Heatwave in Shanghai,Lower Reaches of the Yangtze River Valley:Combined Influences of Multiscale Variabilities

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Advances in Atmospheric Sciences 2024年第4期41卷 593-607页

作者： Ping LIANG Zhiqi ZHANG Yihui DING Zeng-Zhen HU Qi CHEN Key Laboratory of Cities’Mitigation and Adaptation to Climate Change in Shanghai Shanghai Regional Climate CenterChina Meteorological AdministrationShanghai 200030China National Climate Center China Meteorological AdministrationBeijing 100081China Climate Prediction Center NCEP/NWS/NOAACollege ParkMD 20740USA

In the summer of 2022,China(especially the Yangtze River Valley,YRV)suffered its strongest heatwave(HW)event since *** this study,we examined the influences of multiscale variabilities on the 2022 extreme HW in the lower reaches of the YRV,focusing on the city of *** found that about 1/3 of the 2022 HW days in Shanghai can be attributed to the long-term warming trend of global *** mid-summer of 2022,an enhanced western Pacific subtropical high(WPSH)and anomalous double blockings over the Ural Mountains and Sea of Okhotsk,respectively,were associated with the persistently anomalous high pressure over the YRV,leading to the extreme *** Pacific Decadal Oscillation played a major role in the anomalous blocking pattern associated with the HW at the decadal time ***,the positive phase of the Atlantic Multidecadal Oscillation may have contributed to regulating the formation of the double-blocking *** warming of both the warm pool of the western Pacific and tropical North Atlantic at the interannual time scale may also have favored the persistency of the double blocking and the anomalously strong *** the subseasonal time scale,the anomalously frequent phases 2-5 of the canonical northward propagating variability of boreal summer intraseasonal oscillation associated with the anomalous propagation of a weak Madden-Julian Oscillation suppressed the convection over the YRV and also contributed to the ***,the 2022 extreme HW originated from multiscale forcing including both the climate warming trend and air-sea interaction at multiple time scales.

关键词： extreme heatwave multiscale variability air-sea interaction warming trend Yangtze River Valley Shanghai

Assimilation of GOES-R Geostationary Lightning Mapper Flash Extent Density Data in GSI 3DVar, EnKF, and Hybrid En3DVar for the Analysis and Short-Term Forecast of a Supercell Storm Case

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Advances in Atmospheric Sciences 2024年第2期41卷 263-277页

作者： Rong KONG Ming XUE Edward R.MANSELL Chengsi LIU Alexandre O.FIERRO Center for Analysis and Prediction of Storms Norman Oklahoma 73072U.S.A University of Oklahoma Norman Oklahoma 73072U.S.A noaa/National Severe Storms Laboratory NormanOklahoma 73072U.S A.4Zentralanstalt für Meteorologie und Geodynamik Department of Forecasting Models-ZAMGVienna 1190Austria

Capabilities to assimilate Geostationary Operational Environmental Satellite “R-series ”(GOES-R) Geostationary Lightning Mapper(GLM) flash extent density(FED) data within the operational Gridpoint Statistical Interpolation ensemble Kalman filter(GSI-EnKF) framework were previously developed and tested with a mesoscale convective system(MCS) case. In this study, such capabilities are further developed to assimilate GOES GLM FED data within the GSI ensemble-variational(EnVar) hybrid data assimilation(DA) framework. The results of assimilating the GLM FED data using 3DVar, and pure En3DVar(PEn3DVar, using 100% ensemble covariance and no static covariance) are compared with those of EnKF/DfEnKF for a supercell storm case. The focus of this study is to validate the correctness and evaluate the performance of the new implementation rather than comparing the performance of FED DA among different DA schemes. Only the results of 3DVar and pEn3DVar are examined and compared with EnKF/DfEnKF. Assimilation of a single FED observation shows that the magnitude and horizontal extent of the analysis increments from PEn3DVar are generally larger than from EnKF, which is mainly caused by using different localization strategies in EnFK/DfEnKF and PEn3DVar as well as the integration limits of the graupel mass in the observation operator. Overall, the forecast performance of PEn3DVar is comparable to EnKF/DfEnKF, suggesting correct implementation.

关键词： GOES-R lightning data assimilation EnKF EnVar

Value-added Impact of Geostationary Hyperspectral Infrared Sounders on Local Severe Storm Forecasts——via a Quick Regional OSSE

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Advances in Atmospheric Sciences 2018年第10期35卷 1217-1230页

作者： Zhenglong LI Jun LI Pei WANG Agnes LIM Jinlong LI Timothy J.SCHMIT Robert ATLAS Sid-Ahmed BOUKABARA Ross N.HOFFMAN Cooperative Institute for Meteorological Satellite Studies University of Wisconsin-Madison Center for Satellite Applications and Research NOAA Atlantic Oceanographic and Meteorological Laboratory OAR/NOAA Center for Satellite Applications and Research NOAA

Accurate atmospheric temperature and moisture information with high temporal/spatial resolutions are two of the key parameters needed in regional numerical weather prediction(NWP) models to reliably predict high-impact weather events such as local severe storms(LSSs). High spectral resolution or hyperspectral infrared(HIR) sounders from geostationary orbit(GEO) provide an unprecedented source of near time-continuous, three-dimensional information on the dynamic and thermodynamic atmospheric fields—an important benefit for nowcasting and NWP-based forecasting. In order to demonstrate the value of GEO HIR sounder radiances on LSS forecasts, a quick regional OSSE(Observing System Simulation Experiment)framework has been developed, including high-resolution nature run generation, synthetic observation simulation and validation, and impact study on LSS forecasts. Results show that, on top of the existing LEO(low earth orbit) sounders, a GEO HIR sounder may provide value-added impact [a reduction of 3.56% in normalized root-mean-square difference(RMSD)] on LSS forecasts due to large spatial coverage and high temporal resolution, even though the data are assimilated every 6 h with a thinning of 60 km. Additionally, more frequent assimilations and smaller thinning distances allow more observations to be assimilated, and may further increase the positive impact from a GEO HIR sounder. On the other hand, with denser and more frequent observations assimilated, it becomes more difficult to handle the spatial error correlation in observations and gravity waves due to the limitations of current assimilation and forecast systems(such as a static background error covariance). The peak reduction of 4.6% in normalized RMSD is found when observations are assimilated every 3 h with a thinning distance of 30 km.

关键词： OSSE hyperspectral sounder high-impact weather

Study of atmospheric CO2 and CH4 at Longfengshan WMO/GAW regional station： The variations, trends, influence of local sources/sinks, and transport

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Science China Earth Sciences 2017年第10期60卷 1886-1895页

作者： FANG ShuangXi Pieter P.TANS YAO Bo LUAN Tian WU YanLing YU DaJiang Meteorological Observation Centre (MOC) China Meteorological Administration (CMA) Beijing 100081 China Earth System Research Laboratory (esrl) Naiional Oceanic and Atmospheric Administration (NOAA) Boulder CO 80305-3337 USA Chinese Academy of Meteorological Seiences (CAMS) China Meteorological Administration (CMA) Beijing 100081 China Longfengshan Regional Background Station China Meteorological Administration (CMA) Harbin 150001 China

Atmospheric CO_2 and CH_4 have been continuously measured since 2009 at Longfengshan WMO/GAW station(LFS) in China. Variations of the mole fractions, influence of long-distance transport, effects of local sources/sinks and the characteristics of synoptic scale variations have been studied based on the records from 2009 to 2013. Both the CO_2 and CH_4 mole fractions display increasing trends in the last five years, with growth rates of 3.1±0.02 ppm yr.1 for CO_2 and 8±0.04 ppb yr.1(standard error, 1-σ)for CH_4. In summer, the regional CO_2 mole fractions are apparently lower than the Marine Boundary Layer reference, with the lowest value of.13.6±0.7 ppm in July, while the CH_4 values are higher than the MBL reference, with the maximum of 139±6 *** 9 to 17(Local time, LT) in summer, the atmospheric CO_2 mole fractions at 10 m a.g.l. are always lower than at 80 m, with a mean difference of.1.1±0.2 ppm, indicating that the flask sampling approach deployed may underestimate the background mole fractions in summer. In winter, anthropogenic emissions dominate the regional CO_2 and CH_4 mole fractions. Cluster analysis of backward trajectories shows that atmospheric CO_2 and CH_4 at LFS are influenced by anthropogenic emissions from the southwest(Changchun and Jilin city) all year. The synoptic scale variations indicate that the northeastern China plain acts as an important source of atmospheric CO_2 and CH_4 in winter.

关键词： Carbon dioxide Methane Observation Backward trajectory Atmospheric transport

APPLICATION OF NONLINEAR MULTI-CHANNEL ALGORITHMS FOR ESTIMATING SEA SURFACE TEMPERATURE WITH noaa 14 AVHRR DATA

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Chinese Journal of Oceanology and Limnology 2000年第3期18卷 199-207页

作者：李晓峰 noaa Science Center CampSprings 美国 MD 2 0 746

noaa global operational noaa/AVHRR Nonlinear Sea Surface Temperature (NLSST) retrieval algorithms were used to generate Global Area Coverage (GAC) sea surface temperature (SST) measurements in the global ocean in 1998. The accuracy of SST retrieved from daytime split window NLSST algorithm and nighttime triple window NLSST algorithm for noaa 14 AVHRR data was investigated in this study. A matchup dataset of drifting buoys and noaa 14 satellite measurements in the global ocean was generated to validate these operational split window and triple window algorithms. For noaa 14 in 1998, we had 14095 and 22643 satellite and buoy matchups that matched within 25 km and 4 hours for daytime and nighttime, respectively. The satellite derived SST had a bias of less than 0.1℃ and standard deviation of about 0.5℃. This study also showed that the NLSST algorithm provided the same order of SST accuracy in different time of the year and under a wide range of satellite zenith angle and water vapor represented by the channel 4 and 5 brightness temperature difference. Therefore, NLSST algorithms are usually independent of season, geographic location, or atmospheric moisture content. Comparison between the low resolution AVHRR GAC data accuracy and high resolution Local Area Coverage (LAC) data accuracy is also discussed.

关键词： sea surface temperature (SST) noaa/AVHRR nonlinear SST algorithm

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大洋钻探有什么惊人发现

十万个为什么（探索版） 2024年第7期 12-17页

作者：李阳阳无同济大学海洋与地球科学学院 IODP noaa NASA 维基百科视觉中国

如果你目赌过大洋钻探过去50余年在全球海域的钻孔位置图,便会发现这些钻孔星罗棋布!4000多口井,获取的岩芯总长40多万米,比1000个东方明珠电视塔高度加起来还长。这些岩芯可不一般,它们就像历史书一样记载了千万年来地球海陆变迁的历... 详细信息

如果你目赌过大洋钻探过去50余年在全球海域的钻孔位置图,便会发现这些钻孔星罗棋布!4000多口井,获取的岩芯总长40多万米,比1000个东方明珠电视塔高度加起来还长。这些岩芯可不一般,它们就像历史书一样记载了千万年来地球海陆变迁的历史。而大洋钻探把这些埋没在海底的“史书”捞了上来,其中有什么惊人发现呢?

关键词：东方明珠电视塔钻孔位置海陆变迁全球海域岩芯历史

Trends in Extremes of Surface Humidity, Temperature, and Summertime Heat Stress in China

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Advances in Atmospheric Sciences 2001年第5期18卷 742-751页

作者： Julian X.L. Wang and Dian J. Gaffen noaa/ Air Resources Laboratory, Silver Spring, MD, 20910, USA noaa/ Air Resources Laboratory Silver Spring USA

In the past half century, the mean summertime temperature in China has increased, with nights warm- ing more than days. Using surface station observations, we show that the frequency of extreme heat-stress events in China, caused by extremely hot and humid days as well as by heatwaves lasting for a few days, has increased over the period from 1951 to 1994 When humidity is high, hot weather can cause heat stress in humans. The increased heatrstress trend may pose a public health problem

关键词： Trend detection Climate change Public health

Applications of AMSR-E Measurements for Tropical Cyclone Predictions PartⅠ: Retrieval of Sea Surface Temperature and Wind Speed

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Advances in Atmospheric Sciences 2008年第2期25卷 227-245页

作者： Banghua YAN Fuzhong WENG noaa Joint Center for Satellite Data Assimilation Camp Springs MD USA noaa/NESDIS/Center for Satellite Applications and Research Camp Springs MD USA

Existing satellite microwave algorithms for retrieving Sea Surface Temperature （SST） and Wind （SSW） are applicable primarily for non-raining cloudy conditions. With the launch of the Earth Observing System （EOS） Aqua satellite in 2002, the Advanced Microwave Scanning Radiometer （AMSRoE） onboard provides some unique measurements at lower frequencies which are sensitive to ocean surface parameters under adverse weather conditions. In this study, a new algorithm is developed to derive SST and SSW for hurricane predictions such as hurricane vortex analysis from the AMSRoE measurements at 6.925 and 10.65 GHz. In the algorithm, the effects of precipitation emission and scattering on the measurements are properly taken into account. The algorithm performances are evaluated with buoy measurements and aircraft dropsonde data. It is found that the root mean square （RMS） errors for SST and SSW are about 1.8 K and 1.9 m s^- 1, respectively, when the results are compared with the buoy data over open oceans under precipitating clouds （e.g., its liquid water path is larger than 0.5 mm）, while they are 1.1 K for SST and 2.0 m s^-1 for SSW, respectively, when the retrievals are validated against the dropsonde measurements over warm oceans. These results indicate that our newly developed algorithm can provide some critical surface information for tropical cycle predictions. Currently, this newly developed algorithm has been implemented into the hybrid variational scheme for the hurricane vortex analysis to provide predictions of SST and SSW fields.

关键词： Ocean surface temperature ocean surface wind AMSR-E hurricane vortex analysis