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Interdecadal Change of the Northward Jump Time of the Western Pacific Subtropical High in Association with the Pacific Decadal Oscillation

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Journal of meteorological Research 2015年第1期29卷 59-71页

作者：叶天舒申茜王阔张志森赵俊虎 College of Atmospheric Sciences Lanzhou University Laboratory for Climate Studies National Climate CenterChina Meteorological Administration

In this paper, the northward jump time of the western Pacific subtropical high（WPSH） is defined and analyzed on the interdecadal timescale. The results show that under global warming, significant interdecadal changes have occurred in the time of the WPSH northward jumps. From 1951 to 2012, the time of the first northward jump of WPSH has changed from ＂continuously early＂ to ＂continuously late＂, with the transition occurring in 1980. The time of the second northward jump of WPSH shows a similar change, with the transition occurring in 1978. In this study, we offer a new perspective by using the time of the northward jump of WPSH to explain the eastern China summer rainfall pattern change from ＂north-abundant-southbelow-average＂ to ＂south-abundant-north-below-average＂ at the end of the 1970 s. The interdecadal change in the time of the northward jump of WPSH corresponds not only with the summer rainfall pattern, but also with the Pacific decadal oscillation（PDO）. The WPSH northward jump time corresponding to the cold（warm） phase of the PDO is early（late）. Although the PDO and the El Nino–Southern Oscillation（ENSO）both greatly influence the time of the two northward jumps of WPSH, the PDO＇s effect is noticed before the ENSO＇s by approximately 1–2 months. After excluding the ENSO influence, we derive composite vertical atmospheric circulation for different phases of the PDO. The results show that during the cold（warm）phase of the PDO, the atmospheric circulations at 200, 500, and 850 h Pa all contribute to an earlier（later）northward jump of the WPSH.

关键词： northward jump of WPSH interdecadal change summer precipitation Pacific decadal oscillation (PDO)

Simulation of Heavy Rainfall Events during Retreat Phase of Summer Monsoon Season over Parts of Andhra Pradesh

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International Journal of Geosciences 2012年第4期3卷 737-748页

作者： O. S. R. U. Bhanu Kumar P. Suneetha S. Ramalingeswara Rao M. Satya Kumar Andhra University regional meteorological centre

The main aim of this paper is to simulate monsoon heavy rainfall episodes that caused floods across some parts of Andhra Pradesh (AP) state, India during 29th September through 2nd October, 2009. A heavy rainfall quantity of 21 cm was observed near Amaravathi station (16.15°N;80.5°E) in Guntur district due to a meso-α low pressure system extended from the Bay of Bengal and widespread rainfall episodes were also appeared to many adjoining places in other three districts namely Mahaboob Nagar, Kurnool and Krishna in AP state simultaneously on 29th September. The rainy situation continued till 2nd October and caused floods over above districts of AP state which lead to a death toll of 33 people and heavy crop loss. To quantify the above catastrophic monsoon heavy precipitation events a high resolution (9 km) Weather Research and Forecast (WRF-ARW) model is centered at Amaravathi station to simulate rainfall episodes over the study region. In the present case study the simulated sensitive experiment highlights the dynamical characteristics of the meso-α system interms of circulation changes at different levels. Secondly, the thermodynamical characteristics for the generation of convective activity of this meso-α event in terms of Convective Available Potential Energy (CAPE) and Convective Inhibition Energy (CINE) are also simulated. Dynamical and thermodynamical simulated results support heavy rainfall episodes due to a low pressure system around Amaravathi station. Thus circulation changes, high CAPE and low CINE magnitudes have well defined not only the strength of meso-α system, but also quantum of rain-fall to a tune of 19 cm near Amaravathi station on 29th September. The observed rainfall was 21 cm on 29th September and thus this model underestimates rainfall about 9.5% not only at Amaravathi station, but also at other stations as well. Similar results are noticed over the study region on other three days. In this numerical study heavy rainfall events are better re

关键词： Meso-α Low Pressure Cumulus Parameterization Heavy Rainfall Floods

Dust storms and loess accumulation on the Tibetan Plateau: A case study of dust event on 4 March 2003 in Lhasa

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Chinese Science Bulletin 2004年第9期49卷 953-960页

作者： FANG Xiaomin HAN Yongxiang MA Jinghui SONG Lianchun YANG Shengli ZHANG Xiaoye Key Laboratory of Western China's Environmental Systems (lanzhou University) Ministry of Education & College of Resources and Environment Lanzhou University Lanzhou 730000 China State Key Laboratory of Loess and Quatermary Geology Institute of Earth Environment Chinese Academy of Sciences Xi'an 710054 China lanzhou Arid meteorological Instiute of China meteorological Bu-reau Lanzhou 730000 China

Whether the Tibetan Plateau is a significant dust source area is of great importance, because this is re-lated to the understanding of sources, accumulation and environmental effects of dusts on the Tibetan Plateau and in the Far East-Pacific Ocean regions as well as to the evolution of coupling of the Tibetan Plateau and atmosphere-ocean- continent exchange. Synoptic dynamics and remote sensing tracing of a dust storm on 3 to 5 March, 2003 in Lhasa on South Tibet demonstrate that the Tibetan Plateau possesses all factors and conditions of generating dust storms. Accom-panied with this dust storm is a strong ascending stream on the Plateau which has raised various sizes of dust particles into different levels. The lifted coarse particles were largely fallen down and accumulated as loess on the eastern Tibetan Plateau, and the fine particles were translated by the west-erly jet and subsided in the northern Pacific Ocean. The spa-tial-temporal distribution of dust-storms between years 1961 and 2000 on the Plateau shows that dust-storms mainly occur in winter and early spring with high frequency, and the path of dust storm moves gradually from south to north, which is closely coupled with the northward moving of the westerly jet from winter to spring over the Tibetan Plateau. Com-pared with other twelve dust source areas in China, the Ti-betan Plateau is one of the key dust source areas for the long-distance transport because its high occurring frequency and elevation cause fine particles easily to be lifted into the zone of the westerly jet.

关键词：沙尘暴黄土沉积青藏高原拉萨沙尘来源地区 2003年

Aerosol structure and vertical distribution in a multi-source dust region

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Journal of Environmental Sciences 2012年第8期24卷 1466-1475页

作者： Jie Zhang Qiang Zhang Congguo Tang Yongxiang Han Key Laboratory of meteorological Disaster Ministry of Education and Jiangsu ProvinceNanjing University of Information Science&TechnologyNanjing 210044China Institute of Arid Meteorology China Meteorological AdministrationLanzhou 730020China

The vertical distribution of aerosols was directly observed under various atmospheric conditions in the free troposphere using surface micro-pulse lidar （MPL4） at the Zhangye Station （39.08°N, 100.27°E） in western China in the spring of 2008. The study shows that the aerosol distribution over Zhangye can be vertically classified into upper, middle and lower layers with altitudes of 4.5 to 9 km, 2.5 to 4.5 kin, and less than 2.5 km, respectively. The aerosol in the upper layer originated from the external sources at higher altitude regions, from far desert regions upwind of Zhangye or transported from higher atmospheric layers by free convection, and the altitude of this aerosol layer decreased with time; the aerosols in the middle and lower layers originated from both external and local sources. The aerosol extinction coefficients in the upper and lower layers decreased with altitude, whereas the coefficient in the middle layer changed only slightly, which suggests that aerosol mixing occurs in the middle layer. The distribution of aerosols with altitude has three features： a single peak that forms under stable atmospheric conditions, an exponential decrease with altitude that occurs under unstable atmospheric conditions, and slight change in the mixed layer. Due to the impact of the top of the atmospheric boundary layer, the diurnal variation in the aerosol extinction coefficient has a single peak, which is higher in the afternoon and lower in the morning.

关键词： aerosol profile distribution shape upper boundary

CRA-40/Atmosphere—The First-Generation Chinese Atmospheric Reanalysis(1979–2018):System Description and Performance Evaluation

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Journal of meteorological Research 2023年第1期37卷 1-19页

作者： Zhiquan LIU Lipeng JIANG Chunxiang SHI Tao ZHANG Zijiang ZHOU Jie LIAO Shuang YAO Jingwei LIU Minyan WANG Huiying WANG Xiao LIANG Zhisen ZHANG Yan YAO Ting ZHU Zhe CHEN Wenhui XU Lijuan CAO Hui JIANG Kaixi HU National meteorological Information centre China Meteorological Administration(CMA)Beijing 100081China National Center for Atmospheric Research BoulderCO 80301USA CMA Earth System Modeling and Prediction centre China Meteorological AdministrationBeijing 100081China

Atmospheric reanalysis reproduces the past atmospheric conditions through assimilation of historical meteorological observations with fixed version of a numerical weather prediction(NWP)model and data assimilation(DA)*** is widely used in weather,climate,and even business-related research and *** paper reports the development of CMA’s first-generation global atmospheric reanalysis(RA)covering 1979–2018(CRA-40;CRA refers to CMA-RA).CRA-40 is produced by using the Global Spectral Model(GSM)/Gridpoint Statistical Interpolation(GSI)at a 6-h time interval and a TL574 spectral(34-km)resolution with the model top at 0.27 hPa.A large number of reprocessed satellite data and widely collected conventional observations were assimilated during the reanalyzing process,including the reprocessed atmospheric motion vector(AMV)products from FY-2C/D/E/G satellites,dense conventional observations(at about 120 radiosonde and 2400 synoptic stations)over China,as well as MWHS-2 and GNSS-RO observations from *** reanalysis fitting to observations is improved over time,especially for surface pressure with root-mean-square error reduced from 1.05 hPa in 1979 to 0.8 hPa,and for upper air temperature from 1.65 K in 1979 to 1.35 K,in *** patterns of global analysis increments for temperature,specific humidity,and zonal wind are consistent with the changes in the observing *** surface temperature from the model’s 6-h forecast reflects the global warming trend *** CRA-40 precipitation pattern matches well with those of GPCP and other ***-40 also successfully captures the QBO and its vertical and temporal development,hemispherical atmospheric circulation change,and moisture transport by the East Asian summer *** is now operationally running in near real time as a climate data assimilation system in CMA.

关键词： CMA reanalysis(CRA) observations data assimilation(DA) forecast model

Dominant Synoptic Patterns and Their Relationships with PM2.5 Pollution in Winter over the Beijing–Tianjin–Hebei and Yangtze River Delta Regions in China

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Journal of meteorological Research 2019年第4期33卷 765-776页

作者： Yuzhi LIU Bing WANG Qingzhe ZHU Run LUO Chuqiao WU Rui JIA Key Laboratory for Semi-Arid Climate Change of the Ministry of Education College of Atmospheric SciencesLanzhou UniversityLanzhou 730000 meteorological Observatory Unit 95021 Yichang 441000

This paper concerns about the episodes of PM2.5 pollution that frequently occur in China in winter *** severity of PM2.5 pollution is strongly dependent on the synoptic-scale atmospheric *** combined PM2.5 concentration data and meteorological data with the Hybrid Single Particle Lagrangian Integrated Trajectory model(HYSPLIT4)to investigate the dominant synoptic patterns and their relationships with PM2.5 pollution over the Beijing–Tianjin–Hebei(BTH)and Yangtze River Delta(YRD)regions in the winters of 2014–*** transport of PM2.5 from the BTH to YRD regions was examined by using cluster analysis and *** is found that the level of PM2.5 pollution over the BTH region was higher than that over the YRD *** concentration of PM2.5 in the atmosphere was more closely related to meteorological factors over the BTH *** episodes of PM2.5 pollution over the BTH region in winter were related to weather patterns such as the rear of a high-pressure system approaching the sea,a high-pressure field,a saddle pressure field,and the leading edge of a cold *** contrast,PM2.5 pollution episodes in the YRD region in winter were mainly associated with the external transport of cold air,a high-pressure field,and a uniform pressure *** analysis shows that the trajectories of PM2.5 were significantly different under different weather ***2.5 would be transported from the BTH to the YRD within 48 h when the PM2.5 pollution episodes were associated with three different kinds of weather patterns:the rear of a highpressure system approaching the sea,the high-pressure field,and the leading edge of a cold front over the BTH *** suggests a possible method to predict PM2.5 pollution episodes based on synoptic-scale patterns.

关键词： PM2.5 pollution episodes synoptic patterns Beijing-Tianjin-Hebei (BTH) Yangtze River Delta (YRD)

Analysis on the impact of two winter precipitation episodes on PM_(2.5) in Beijing

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Environmental Science and Ecotechnology 2021年第1期5卷 41-48页

作者： Hengde Zhang Qi Jiang Jikang Wang Kaifei Li Fei Wang National meteorological centre Beijing100081China Shanghai meteorological Service Shanghai200030China Chinese Academy of meteorological Sciences Beijing100081China

In this paper,the circulation background,the characteristics of meteorological elements configuration in the boundary layer and the stable meteorological conditions in two precipitation episodes(during February 19-21,2015 and February 10-13,2016,respectively)within the Beijing-Tianjin-Hebei region are compared and *** from conventional meteorological observations,air quality monitoring,reanalysis and numerical models are *** results show that before the two precipitation processes in 2015 and 2016,the circulations in the middle and high latitudes of Asia and Europe demonstrate“two troughs and one ridge”.Besides,the weather is stable and the pollutant concentration is relatively *** the precipitation,the circulation is relatively stable for the episode in 2015,and no obvious change in the synoptic system is ***,during the episode in 2016,the formation of blocking high and the enhancement of the average ridge in western Asia cause obvious change in the *** simulation results show that significant removal can be detected in both cases,and the PM_(2.5) wet deposition fluxes are 647 g/ha and 486 g/ha,respectively,with the removal in 2015 slightly stronger than that in *** removal and dissipation of pollutants is determined by the atmospheric diffusion conditions and the precipitation,especially in the former *** the case of February 2016,good diffusion conditions and the precipitation demonstrate obvious PM_(2.5) removal *** the case of February 2015,the longstanding calm wind with high humidity and the physical quantity configuration in the lower mixed layer lead to the poor pollutant removal.

关键词： PM_(2.5) Wet removal Static and stable Atmospheric diffusion conditions

A Modeling Study of Effective Radiative Forcing and Climate Response Due to Tropospheric Ozone

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Advances in Atmospheric Sciences 2016年第7期33卷 819-828页

作者： Bing XIE Hua ZHANG Zhili WANG Shuyun ZHAO Qiang FU Key Laboratory for Semi-Arid Climate Change of the Ministry of Education College of Atmosphere ScienceLanzhou UniversityLanzhou 730000 Laboratory for Climate Studies of China meteorological Administration National Climate CenterChina Meteorological AdministrationBeijing 100081 Chinese Academy of meteorological Sciences Beijing 100081 Department of Atmospheric Sciences University of WashingtonSeattle98195USA

This study simulates the effective radiative forcing （ERF） of tropospheric ozone from 1850 to 2013 and its effects on global climate using an aerosol-climate coupled model, BCC_AGCM2.0. I_CUACE/Aero, in combination with OMI （Ozone Monitoring Instrument） satellite ozone data. According to the OMI observations, the global annual mean tropospheric col- umn ozone （TCO） was 33.9 DU in 2013, and the largest TCO was distributed in the belts between 30°N and 45°N and at approximately 30°S; the annual mean TCO was higher in the Northern Hemisphere than that in the Southern Hemisphere; and in boreal summer and autumn, the global mean TCO was higher than in winter and spring. The simulated ERF due to the change in tropospheric ozone concentration from 1850 to 2013 was 0.46 W m-2, thereby causing an increase in the global annual mean surface temperature by 0.36°C, and precipitation by 0.02 mm d-1 （the increase of surface temperature had a significance level above 95%）. The surface temperature was increased more obviously over the high latitudes in both hemispheres, with the maximum exceeding 1.4°C in Siberia. There were opposite changes in precipitation near the equator, with an increase of 0.5 mm d- 1 near the Hawaiian Islands and a decrease of about -0.6 mm d- 1 near the middle of the Indian Ocean.

关键词： tropospheric ozone effective radiative forcing climate effect BCC_AGCM2.0. I_CUACE/Aero

TCRAIN–A DATABASE OF TROPICAL CYCLONE RAINFALL PRODUCTS FOR NORTH INDIAN OCEAN

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Tropical Cyclone Research and Review 2014年第2期3卷 122-129页

作者： S.BALACHANDRAN B.GEETHA K.RAMESH N.SELVAM Cyclone Warning Research centre Regional Meteorological Centre

Analysis of tropical cyclone(TC) rainfall characteristics helps in understanding and improving quantitative precipitation forecasts of TCs. Based on the Tropical Rainfall Measuring Mission(TRMM) rainfall data for the period of 2000-2010, a TC rainfall database –Tropical Cyclone Rainfall Analysis for North Indian Ocean(TCRAIN) is developed to study the precipitation characteristics during various stages of life cycle of TCs of the North Indian Ocean(NIO). Three rainfall products, viz., frequency distribution of rain rate, azimuthally averaged radial profile of rain rate and quadrant mean rain rate with respect to the TC centre and the direction of motion of the TC are generated in a Lagrangian frame of coordinate system for 5 intensity stages of life cycle of each cyclone over NIO. Using this TCRAIN database, composites of frequency distribution of rain rates as well as quadrant mean rain rate for TCs of NIO are generated to bring out probable rain rates and asymmetric structure in rainfall distribution. Rainfall profiles for individual cases are likely to deviate from the climatological profiles under different environmental and oceanic conditions. TCRAIN database would serve as a useful tool for carrying out intensity based analytical studies on structure of rainfall associated with cyclones of NIO through ready depiction of TC rainfall profiles.

关键词： tropical cyclone rainfall radial profi le quadrant mean TCRAIN