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Atmospheric and Oceanic Science Letters 2025年第1期18卷 6-11页

作者： Haoyu Zhou Pang-Chi Hsu Lin Chen Yitian Qian Key Laboratory of meteorological disaster Ministry of Education/Joint International Research Laboratory of Climate and Environmental Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science and TechnologyNanjingChina

During the boreal summer,intraseasonal oscillations exhibit significant interannual variations in intensity over two key regions:the central-western equatorial Pacific(5°S-5°N,150°E-150°W)and the subtropical Northwestern Pacific(10°-20°N,130°E-175°W).The former is well-documented and considered to be influenced by the ENSO,while the latter has received comparatively less attention and is likely influenced by the Pacific Meridional Mode(PMM),as suggested by partial correlation analysis *** elucidate the physical processes responsible for the enhanced(weakened)intraseasonal convection over the subtropical northwestern Pacific during warm(cold)PMM years,the authors employed a moisture budget *** findings reveal that during warm PMM years,there is an increase in summer-mean moisture over the subtropical northwestern *** increase interacts with intensified vertical motion perturbations in the region,leading to greater vertical moisture advection in the lower troposphere and consequently resulting in convective *** a process is pivotal in amplifying intraseasonal convection *** observational findings were further verified by model experiments forced by PMM-like sea surface temperature patterns.

关键词： Boreal summer intraseasonal oscillation Interannual variability Pacific Meridional Mode Moisture budget analysis

Application of the improved dung beetle optimizer,muti-head attention and hybrid deep learning algorithms to groundwater depth prediction in the Ningxia area,China

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 18-23页

作者： Jiarui Cai Bo Sun Huijun Wang Yi Zheng Siyu Zhou Huixin Li Yanyan Huang Peishu Zong Collaborative Innovation center on forecast and Evaluation of meteorological disasters/Key Laboratory of meteorological disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment ChangeNanjing University of Information Science and TechnologyNanjingChina Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) ZhuhaiChina China meteorological Administration Key Laboratory of Transportation MeteorologyNanjingChina Jiangsu meteorological Observatory NanjingChina

Due to the lack of accurate data and complex parameterization,the prediction of groundwater depth is a chal-lenge for numerical *** learning can effectively solve this issue and has been proven useful in the prediction of groundwater depth in many *** this study,two new models are applied to the prediction of groundwater depth in the Ningxia area,*** two models combine the improved dung beetle optimizer(DBO)algorithm with two deep learning models:The Multi-head Attention-Convolution Neural Network-Long Short Term Memory networks(MH-CNN-LSTM)and the Multi-head Attention-Convolution Neural Network-Gated Recurrent Unit(MH-CNN-GRU).The models with DBO show better prediction performance,with larger R(correlation coefficient),RPD(residual prediction deviation),and lower RMSE(root-mean-square error).Com-pared with the models with the original DBO,the R and RPD of models with the improved DBO increase by over 1.5%,and the RMSE decreases by over 1.8%,indicating better prediction *** addition,compared with the multiple linear regression model,a traditional statistical model,deep learning models have better prediction performance.

关键词： Groundwater depth Multi-head attention Improved dung beetle optimizer CNN-LSTM CNN-GRU Ningxia

Comparative Analysis of Energy Characteristics of Two Southwest Vortices in sichuan Under Similar Circulation Backgrounds

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Journal of Tropical Meteorology 2024年第2期30卷 168-179页

作者：周春花张驹肖红茹 sichuan meteorological disaster prevention technology center Chengdu 610072 China Chengdu meteorological Bureau Chengdu 610072 China sichuan meteorological Observatory Chengdu 610072 China

Based on ERA5 reanalysis data,the present study analyzed the thermal energy development mechanism and kinetic energy conversion characteristics of two extreme rainstorm processes in relation to the shallow southwest vortex in the warm-sector during a“rain-generated vortex”process and the deep southwest vortex in a“vortex-generated rain”*** findings were as follows:(1)During the extreme rainstorm on August 11,2020(hereinafter referred to as the“8·11”process),intense surface heating and a high-energy unstable environment were *** mesoscale convergence system triggered convection to produce heavy rainfall,and the release of latent condensation heat generated by the rainfall promoted the formation of a southwest *** significant increase(decrease)in atmospheric diabatic heating and kinetic energy preceded the increase(decrease)in *** contrast,the extreme rainstorm on August 16,2020(hereinafter referred to as the“8·16”process)involved the generation of southwest vortex in a low-energy and highhumidity *** dynamic uplift of the southwest vortex triggered rainfall,and the release of condensation latent heat from rainfall further strengthened the development of the southwest *** significant increase(decrease)in atmospheric diabatic heating and kinetic energy exhibited a delayed progression compared to the increase(decrease)in vorticity.(2)The heating effect around the southwest vortex region was non-uniform,and the heating intensity varied in different *** the“8·11”process,the heating effect was the strongest in the initial stage,but weakened during the vortex's *** the contrary,the heating effect was initially weak in the“8·16”process,and intensified during the development stage.(3)The available potential energy of the“8·11”process significantly increased in kinetic energy converted from rotational and divergent winds through baroclinic action,and the divergent wind energy continued to convert into rotatio

关键词： southwest vortex similar circulation background diabatic heating kinetic energy spatial non-uniform heating effect

Raindrop Size Distribution Measurements at High Altitudes in the Northeastern Tibetan Plateau during Summer

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Advances in Atmospheric Sciences 2023年第7期40卷 1244-1256页

作者： Huibang HAN Yuxin ZHANG Jianbing TIAN Xiaoyan KANG meteorological disaster prevention technology center in Qinghai Province Xining 810000China Key Laboratory for disaster prevention and Mitigation in Qinghai Province Xining 810000China

Characteristics of raindrop size distribution during summer are studied by using the data from six Parsivel disdrometers located in the northeastern Tibetan *** analysis focuses on convective and stratiform precipitation at high altitudes from 2434 m to 4202 *** results show that the contribution of stratiform and convective precipitation with rain rate between 1≤R<5 mm h^(-1) to the total precipitation increases with altitude,and the raindrop scale and number concentration of convective precipitation is larger than that for stratiform *** droplet size spectra of both stratiform and convective precipitation shows a single peak with a peak particle size between 0.31–0.50 mm,and they have essentially the same peak particle size and number concentration at the same *** maximum spectral widths of stratiform clouds are between 4 mm and 5 mm,while those of convective clouds range from 4 mm to 8 *** Gamma distribution is more suitable than the Marshall-Palmer distribution in terms of the actual raindrop spectrum *** stratiform precipitation particles are smaller with higher number concentration,while the opposite is true for the convective precipitation *** convective precipitation particles drop faster than stratiform precipitation particles when the particle size exceeds 2 mm,and the falling velocity of raindrops after standard curve fitting is underestimated during the observation ***,conventional radar estimation methods would underestimate the precipitation in the Northeastern Tibetan Plateau.

关键词： raindrop size distribution precipitation microphysics Northeastern Tibetan Plateau fall velocity

Crowd sensing data delivery based on tangle DAG network

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The Journal of China Universities of Posts and Telecommunications 2023年第3期30卷 88-98页

作者： Chen Hui Jiang Xiaoling Wu Tianting Mou Xingyu Operation Monitoring Department Jilin Province Meteorological Information Network CenterChangchun 130062China Appraisal Department Jilin Province Meteorological Disaster Prevention Technology CenterChangchun 130062China

In view of the fact that current data delivery methods are not enough to meet the security requirements of today’s distributed crowd sensing,and the data delivery methods are not flexible enough,this paper proposes a crowd sensing data interaction method based on tangle directed acyclic graph(DAG)*** this method,users and platforms are regarded as nodes of the network in the process of performing crowd sensing ***,the heaviest chain is generated through the main chain strategy to ensure the stability of the ***,the hidden Markov model(HMM)prediction model is used to improve the correlation of the perceived data to improve the ***,the confidential transaction and commitment algorithm is used to ensure the reliability of the transaction,overcome the security risks faced by the trusted third party,and simplify the group intelligence aware transaction ***,through simulation experiments,the security and feasibility of the group intelligence aware data delivery method based on tangle DAG network are verified.

关键词： data delivery crowd sensing tangle directed acyclic graph(DAG) confidential transactions

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Relationship between Lightning Activity and Tropospheric Nitrogen Dioxide and the Estimation of Lightning-produced Nitrogen Oxides over China

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Advances in Atmospheric Sciences 2017年第2期34卷 235-245页

作者： Fengxia GUO Xiaoyu JU Min BAO Ganyi LU Zupei LIU Yawen LI Yijun MU Key Laboratory of meteorological disaster Ministry of Education Joint International Research Laboratory of Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disaster/Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological AdministrationNanjing University of Information Science and TechnologyNanjing 210044China Anhui meteorological disaster prevention center Anhui 230061China

To better understand the relationship between lightning activity and nitrogen oxides （NOx） in the troposphere and to estimate lightning-produced NOx （LNOx） production in China more precisely, spatial and temporal distributions of vertical column densities of tropospheric nitrogen dioxide （NO2 VCDs） and lightning activity were analyzed using satellite measure- ments. The results showed that the spatial distribution of lightning activity is greater in the east than in the west of China, as with NO2 VCDs. However, the seasonal and annual variation between lightning and NO2 density show different trends in the east and west. The central Tibetan Plateau is sparsely populated without modem industry, and NO2 VCDs across the plateau are barely affected by anthropogenic sources. The plateau is an ideal area to study LNOx. By analyzing 15 years of satellite data from that region, it was found that lightning density is in strong agreement with annual, spatial and seasonal variations of NO2 VCDs, with a correlation coefficient of 0.79 from the linear fit. Combining Beirle＇s method and the linear fit equation, LNOx production in the Chinese interior was determined to be 0.07 （0.02-0.27） TgN yr-1 for 1997-2012, within the range of 0.016-0.384 TgN yr-1 from previous estimates.

关键词： lightning tropospheric NO2 LNOx

Improved Calculation of Turbulence Parameters Based on Six Tropical Cyclone Cases:Implication to Wind Turbine Design in Typhoon-Prone Areas

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Journal of meteorological Research 2019年第5期33卷 895-904页

作者： Binglan WANG Zhiqiang HE Lili SONG Wenchao CHEN Beijing Jiutian Weather technology Co. Ltd.Beijing 100081 Public meteorological Service center China Meteorological AdministrationBeijing 100081 North China Regional meteorological center Civil Aviation Administration of ChinaBeijing 100621 Guangdong meteorological disaster prevention technology Service center Guangzhou 510080

In view of the absence or insufficiency of tropical cyclone(TC) turbulence parameters in current design standards of wind turbines, in this paper, TC turbulence parameter models with roughness length involved are developed based on six landfall TCs observed from meteorological towers located on various underlying surfaces, so as to provide references for the wind turbine design under TC conditions. Firstly, the roughness length values are examined in order to reduce the effect on turbulence parameters of the various underlying surfaces. On this basis, the reference turbulence intensity is normalized by the roughness length. The related turbulence parameters are parameterized, including the turbulence standard deviation and the turbulence spectrum;and the turbulence parameters available under TC conditions for turbulence turbine design are presented finally. Comparisons of the wind parameter models presented in this paper with those used in current turbine design standards suggest that the former can represent TC characteristics more accurately. In order to withstand TCs, we suggest that the turbulence parameter models recommended in this paper be included in future wind turbine design standards under TC conditions.

关键词： tropical cyclone turbulence parameter models wind turbine

Simulated Sensitivity of the Tropical Cyclone Eyewall Replacement Cycle to the Ambient Temperature Profile

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Advances in Atmospheric Sciences 2017年第9期34卷 1047-1056页

作者： Xulin MA Jie HE Xuyang GE Collaborative Innovation center on Forecast and Evaluation of meteorological disasters Key Laboratory of Meteorological DisasterNanjing University of Information Science and Technology

In this study, the impacts of the environmental temperature profile on the tropical cyclone eyewall replacement cycle are examined using idealized numerical simulations. It is found that the environmental thermal condition can greatly affect the formation and structure of a secondary eyewall and the intensity change during the eyewall replacement cycle. Simulation with a warmer thermal profile produces a larger moat and a prolonged eyewall replacement cycle. It is revealed that the enhanced static stability greatly suppresses convection, and thus causes slow secondary eyewall formation. The possible processes influencing the decay of inner eyewall convection are investigated. It is revealed that the demise of the inner eyewall is related to a choking effect associated with outer eyewall convection, the radial distribution of moist entropy fluxes within the moat region, the enhanced static stability in the inner-core region, and the interaction between the inner and outer eyewalls due to the barotropic instability. This study motivates further research into how environmental conditions influence tropical cyclone dynamics and thermodynamics.

关键词： tropical cyclone eyewall replacement cycle ambient temperature profile

How Does Tropical Cyclone Size Affect the Onset Timing of Secondary Eyewall Formation？

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Journal of meteorological Research 2018年第1期32卷 124-134页

作者： Liang GUAN Xuyang GE Collaborative Innovation center on Forecast and Evaluation of meteorological disasters/Key Laboratory of meteorological disaster Nanjing University of Information Science & Technology Nanjing 210044 Shanghai meteorological Science and technology Service center Shanghai 200030

By using idealized numerical simulations, the impact of tropical cyclone size on secondary eyewall formation（SEF） is examined. Both unbalanced boundary layer and balanced processes are examined to reveal the underlying mechanism. The results show that a tropical cyclone（TC） with a larger initial size favors a quicker SEF and a larger outer eyewall. For a TC with a larger initial size, it will lead to a stronger surface entropy flux, and thus more active outer convection. Meanwhile, a greater inertial stability helps the conversion from diabatic heating to kinetic ***, the progressively broadening of the tangential wind field will induce significant boundary layer imbalances. This unbalanced boundary layer process results in a supergradient wind zone that acts as an important mechanism for triggering and maintaining deep convection. In short, different behaviors of balanced and unbalanced processes associated with the initial wind profile lead to different development rates of the secondary eyewall.

关键词： secondary eyewall formation tropical cyclone size surface entropy flux

Influence of Boundary Layer Mixing Mechanisms on the Simulation of Typhoon Wutip:A Direct Hit on the Xisha Islands in 2013

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Journal of Tropical Meteorology 2024年第3期30卷 211-222页

作者： GUO Tian-yun LI Jiang-nan PANG Si-min MA Xiao-ling School of Atmospheric Sciences and Guangdong Province Key Laboratory for Climate Change and Natural Disaster StudiesSun Yat-sen UniversityZhuhaiGuangdong 519082 China Hunan meteorological Service center Changsha 410118 China Guangxi meteorological disaster prevention center Nanning 530022 China Hunan Key Laboratory of meteorological disaster prevention and Mitigation Changsha 410118 China

In this study,we simulated the tropical cyclone(TC)Wutip,which originated in the South China Sea in 2013,using three planetary boundary layer(PBL)parameterized schemes within the Weather Research and Forecasting model,i.e.,Medium-Range Forecast(MRF),Yonsei University scheme(YSU),and Asymmetric Convective Model Version 2(ACM2),with different vertical mixing *** investigated the effects of different PBL mixing mechanisms on the simulation of TC track,intensity,structure,and *** results reveal that the surface flux and vertical mixing of PBL jointly influenced the TC throughout its lifecycle,and the simulated TC intensity was closely correlated with the eyewall *** three schemes were all first-order and nonlocal closure ***,the MRF scheme was over-mixed,which led to a relatively dryer and warmer near-surface layer,a wetter and colder upper PBL,and thus a simulated eyewall with the smallest wet static energy and weaker ***,the MRF scheme produced the smallest 10-m wind speed,which was closest to the observation,and the weakest TC warm-core structure and *** YSU scheme was similar to the MRF scheme,yet it distinguished itself by incorporating an explicit treatment of the entrainment process at the top of the PBL and developing thermal-free convection above the PBL of the eyewall,which significantly increased the wet static energy over the TC ***,the simulated eyewall was more contracted and steeper with stronger upward motion while the eye area became even warmer,finally leading to the strongest *** precipitation distribution simulated by the YSU scheme was the most consistent with the *** ACM2 scheme used the nonlocal upward and local downward mixed asymmetric convection modes,which reduced the excessive de-velopment of thermal-free convection at the eyewall,and avoided restricting the dynamically forced turbulent motion outside the eyewall,leading to a larger radius of the

关键词： tropical cyclone PBL scheme mixing mechanism WRF