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Radiative Forcing and Climate Response Due to Black Carbon in Snow and Ice

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Advances in Atmospheric Sciences 2011年第6期28卷 1336-1344页

作者：王志立张华沈学顺 center for Atmosphere Watch and services Chinese Academy of Meteorological Sciences China Meteorological Administration Graduate University of Chinese Academy of Sciences National Climate center China Meteorological Administration State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences

The radiative forcing and climate response due to black carbon（BC） in snow and/or ice were investigated by integrating observed effects of BC on snow/ice albedo into an atmospheric general circulation model（BCC AGCM2.0.1） developed by the National Climate center（NCC） of the China meteorological Administration（CMA）.The results show that the global annual mean surface radiative forcing due to BC in snow/ice is ＋0.042 W m 2,with maximum forcing found over the Tibetan Plateau and regional mean forcing exceeding ＋2.8 W m *** global annual mean surface temperature increased 0.071 C due to BC in snow/*** surface radiative forcing was clearly shown in winter and spring and increased the surface temperature of snow/ice in the Northern *** surface temperatures of snow-covered areas of Eurasia and North America in winter（spring） increased by 0.83 C（0.6 C） and 0.83 C（0.46 C）,*** rates also increased greatly,leading to earlier snowmelt and peak runoff *** the rise of surface temperatures in the Arctic,more water vapor could be released into the atmosphere,allowing easier cloud formation,which could lead to higher thermal emittance in the ***,the total cloud forcing could decrease due to increasing cloud cover,which will offset some of the positive feedback mechanism of the clouds.

关键词： black carbon snow/ice radiative forcing climate effects

Modeling Study of Aerosol Indirect Effectson Global Climate with an AGCM

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Advances in Atmospheric Sciences 2010年第5期27卷 1064-1077页

作者：王志立张华沈学顺龚山陵张小曳 Chinese Academy of meteorological Sciences National Climate center China Meteorological Administration center for Numerical Prediction Research and State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences center for Atmosphere Watch and services China Meteorological Administration Air Quality Research Branch Meteorological Service of Canada Toronto Ontario Canada

Aerosol indirect effects （AIEs） on global climate were quantitatively investigated by introducing aerosol–cloud interaction parameterizations for water stratus clouds into an AGCM （BCC AGCM2.0.1）, which was developed by the National Climate center of the China meteorological Administration. The study yielded a global annual mean of -1.14 W m^-2 for the first indirect radiative forcing （IRF）, with an obvious seasonal change. In summer, large forcing mainly occurred in mid to high latitudes of the Northern Hemisphere, whereas in winter, large values were found at 60°S. The second indirect effect led to global annual mean changes in net shortwave flux of -1.03 W m^-2 at the top of the atmosphere （TOA）, which was relatively significant in mid-latitude regions of both hemispheres. The total AIE reduced the global annual means of net shortwave flux at the TOA and of surface temperature by 1.93 W m^-2 and 0.12 K, respectively. Change in surface temperature induced by the total AIE was clearly larger in the Northern Hemisphere （-0.23 K） than in the Southern Hemisphere, where changes were negligible. The interhemispheric asymmetry in surface cooling resulted in significant differences in changes of the interhemispheric annual mean precipitation rate, which could lead to a tendency for the ITCZ to broaden. The total AIE decreased the global annual mean precipitation rate by 0.055 mm df^-1.

关键词： aerosol cloud radiation indirect effect

RPNet: Rice plant counting after tillering stage based on plant attention and multiple supervision network

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The Crop Journal 2023年第5期11卷 1586-1594页

作者： Xiaodong Bai Susong Gu Pichao Liu Aiping Yang Zhe Cai Jianjun Wang Jianguo Yao School of Computer Science and Technology Hainan UniversityHaikou 570228HainanChina Institute of Advanced Technology Nanjing University of Posts and TelecommunicationsNanjing 210003JiangsuChina Agricultural meteorological center Jiangxi Meteorological BureauNanchang 330045JiangxiChina

Rice is a major food crop and is planted worldwide. Climatic deterioration, population growth, farmland shrinkage, and other factors have necessitated the application of cutting-edge technology to achieve accurate and efficient rice production. In this study, we mainly focus on the precise counting of rice plants in paddy field and design a novel deep learning network, RPNet, consisting of four modules: feature encoder, attention block, initial density map generator, and attention map generator. Additionally, we propose a novel loss function called RPloss. This loss function considers the magnitude relationship between different sub-loss functions and ensures the validity of the designed network. To verify the proposed method, we conducted experiments on our recently presented URC dataset, which is an unmanned aerial vehicle dataset that is quite challenged at counting rice plants. For experimental comparison, we chose some popular or recently proposed counting methods, namely MCNN, CSRNet, SANet, TasselNetV2, and FIDTM. In the experiment, the mean absolute error(MAE), root mean squared error(RMSE), relative MAE(rMAE) and relative RMSE(rRMSE) of the proposed RPNet were 8.3, 11.2, 1.2% and 1.6%, respectively,for the URC dataset. RPNet surpasses state-of-the-art methods in plant counting. To verify the universality of the proposed method, we conducted experiments on the well-know MTC and WED datasets. The final results on these datasets showed that our network achieved the best results compared with excellent previous approaches. The experiments showed that the proposed RPNet can be utilized to count rice plants in paddy fields and replace traditional methods.

关键词： Rice Precision agriculture Plant counting Deep learning Attention mechanism

Characteristics and Possible Formation Mechanisms of Severe Storms in the Outer Rainbands of Typhoon Mujigae(1522)

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Journal of meteorological Research 2017年第3期31卷 612-624页

作者： Bingyun WANG Ming WEI Wei HUA Yongli ZHANG Xiaohang WEN Jiafeng ZHENG Nan LI Han LI Yu WU Jie ZHU Mingjun ZHANG Collaborative Innovation center on Forecast and Evaluation of meteorological Disasters Nanjing University of Information Science &Technology College of Atmospheric Sciences Chengdu University of Information Technology/Plateau Atmosphere and Environment Key Laboratory of Sichuan Province hainan meteorological Observatory National Satellite meteorological center

To better understand how severe storms form and evolve in the outer rainbands of typhoons, in this study, we in- vestigate the evolutionary characteristics and possible formation mechanisms for severe storms in the rainbands of Typhoon Mujigae, which occurred during 2-5 October 2015, based on the NCEP-NCAR reanalysis data, conventional observations, and Doppler radar data. For the rainbands far from the inner core （eye and eyewall） of Mujigae （dis- tance of approximately 70-800 kin）, wind speed first increased with the radius expanding from the inner core, and then decreased as the radius continued to expand. The Rankine Vortex Model was used to explore such variations in wind speed. The areas of strong stormy rainbands were mainly located in the northeast quadrant of Mujigae, and overlapped with the areas of high winds within approximately 300-550 km away from the inner core, where the strong winds were conducive to the development of strong storms. A severe convective cell in the rainbands de- veloped into waterspout at approximately 500 km to the northeast of the inner core, when Mujigae was strengthening before it made landfall. Two severe convective cells in the rainbands developed into two tornadoes at approximately 350 km to the northeast of the inner core after Mujigae made landfall. The radar echo bands enhanced to 60 dBZ when mesocyclones occurred in the rainbands and induced tornadoes. The radar echoes gradually weakened after the mesocyclones weakened. The tops of parent clouds of the mesocyclones elevated at first, and then suddenly dropped about 20 min before the tornadoes appeared. Thereby, the cloud top variation has the potential to be used as an early warning of tornado occurrence.

关键词： strong typhoon rainband severe storm tomado Rankine Vortex Model

Discriminant Genetic Algorithm Extended (DGAE) model for seasonal sand and dust storm prediction

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Science China Earth Sciences 2011年第1期54卷 10-18页

作者： YANG YuanQin WANG JiZhi HOU Qing LI Yi ZHOU ChunHong Key Laboratory Jor Atmospheric Chemistry Center for Atmospheric Watch and Services Chinese Academy of Meteorological Sciences China Meteorological Administration Beijing 100081 China

Here we use a Discriminant Genetic Algorithm Extended (DGAE) model to diagnose and predict seasonal sand and dust storm (SDS) activities occurring in Northeast Asia. The study employed the regular meteorological data, including surface data, upper air data, and NCEP reanalysis data, collected from 1980–2006. The regional, seasonal, and annual differences of 3-D atmospheric circulation structures and SDS activities in the context of spatial and temporal distributions were given. Genetic algorithms were introduced with the further extension of promoting SDS seasonal predication from multi-level resolution. Genetic probability was used as a substitute for posterior probability of multi-level discriminants, to show the dual characteristics of crossover inheritance and mutation and to build a non-linear adaptability function in line with extended genetic algorithms. This has unveiled the spatial distribution of the maximum adaptability, allowing the forecast field to be defined by the population with the largest probability, and made discriminant genetic extension possible. In addition, the effort has led to the establishment of a regional model for predicting seasonal SDS activities in East Asia. The model was tested to predict the spring SDS activities occurring in North China from 2007 to 2009. The experimental forecast resulted in highly discriminant intensity ratings and regional distributions of SDS activities, which are a meaningful reference for seasonal SDS predictions in the future.

关键词： sand and dust storms seasonal prediction methodology Discriminant Genetic Algorithm Extended (DGAE) model

VARIATION CHARACTERISTICS OF TROPICAL CYCLONES MAKING LANDFALL IN CHINA AT DIFFERENT INTENSITIES

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Journal of Tropical Meteorology 2011年第3期17卷 268-275页

作者：许向春于玉斌赵大军 Department of Atmospheric Science Lanzhou University hainan Institute of meteorological Science China meteorological Administration Training center Nanjing University of Information Science and Technology

According to the national standard(2006)on tropical cyclone(TC)intensity,TCs are categorized into six intensity types,namely,tropical depression(TD),tropical storm(TS),severe tropical storm(STS), typhoon(TY),severe typhoon(STY),and super severe typhoon(SSTY).Fifty-eight years(1949–2006)of the datasets from the Yearbook of Typhoons and Yearbook of Tropical Cyclones were used to study the variation characteristics of TCs making landfalls in China's Mainland,hainan and Taiwan *** main results are as ***,interannual or interdecadal variations in the number of landfalling TCs at different intensities *** far as long-term trends are concerned,the TD and TS frequencies show a significant linearly decreasing trend while those of STY show a significant linearly increasing ***, a significant period of 6–8 years exist in the variations of annual landfalling TD,TS,and STS frequencies while quasi-16-year periods are found in the annual TY ***,TD and TS are generated mostly over the South China Sea,while TY,STY,and SSTY mostly over the waters southeast of the Bashi Channel and the ocean to the east of the ***,as far as interdecadal trends are concerned,the frequencies of landfalling TD and TS generated over the South China Sea show significant linearly decreasing ***,TY and STY show significant linearly increasing trends.

关键词： statistical characteristics tropical cyclones landfall variation trends

A seaweed-inspired separator for high performance Zn metal batteries:Boosting kinetics and confining side-reactions

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Journal of Energy Chemistry 2025年第2期101卷 191-200页

作者： Qianzhi Gou Horan Luo Long Qu Feilin Yu Kaixin Wang Sida Zhang Ziga Luogu Ben Zhang Yujie Zheng Bingye Song John Wang Meng Li National Innovation center for Industry-Education Integration of Energy Storage MOE Key Laboratory of Low-grade Energy Utilization Technologies and SystemsCQU-NUS Renewable Energy Materials & Devices Joint Laboratory College of Energy & Power Engineering Chongqing University School of Building services Science and Engineering Xi'an University of Architecture and Technology School of Chemistry and Chemical Engineering Chongqing University of Science and Technology Southwest Technology and Engineering Research Institute National University of Singapore (Chongqing) Research Institute

Uncontrolled dendrite growth,sluggish reaction kinetics,and drastic side reactions on the anodeelectrolyte interface are the main obstacles that restrict the application prospect of aqueous zinc-ion *** glass fiber（GF） separator with chemical inertness is almost ineffective in restricting these ***,inspired by the ionic enrichment behavior of seaweed plants,a facile biomass species,anionic sodium alginate（SA）,is purposely decorated on the commercial GF separator to tackle these issues towards Zn *** from the abundant zincophilic functional groups and superior mechanical strength properties,the as-obtained SA@GF separator could act as ion pump to boost the Zn2+transference number（0.68）,reduce the de-solvation energy barrier of hydrated Zn2+,and eliminate the undesired concentration polarization effect,which are verified by experimental tests,theoretical calculations,and finite element simulation,*** on these efficient modulation mechanisms,the SA@GF separator can synchronously achieve well-aligned Zn deposition and the suppression of parasitic ***,the Zn‖Zn coin cell integrated with SA@GF separator could yield a prolonged calendar lifespan over 1230 h(1 mA cm-2and 1 mAh cm-2),exhibiting favorable competitiveness with previously reported separator modification ***,the Zn-MnO2full and pouch cell assembled with the SA@GF separator also delivered superior cycling stability and rate performance,further verifying its practical application *** work provides a new design philosophy to stabilize the Zn anode from the aspect of separator.

关键词： Aqueous zinc-ion batteries Dendrite-free Interfacial reaction kinetics Separator modification Sodium alginate

Role of the 10–20-Day Oscillation in Sustained Rainstorms over hainan,China in October 2010

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Advances in Atmospheric Sciences 2015年第3期32卷 363-374页

作者： QIAO Yunting ZHANG Chunhua JIAN Maoqiu center for Monsoon and Environment Research Department of Atmospheric SciencesSchool of Environmental Science and Engineering Sun Yat-sen University hainan meteorological Observatory

hainan,an island province of China in the northern South China Sea,experienced two sustained rainstorms in October 2010,which were the most severe autumn rainstorms of the past 60 *** August to October 2010,the most dominant signal of hainan rainfall was the 10-20-day *** paper examines the roles of the 10-20-day oscillation in the convective activity and atmospheric circulation during the rainstorms of October 2010 over *** both rainstorms,hainan was near the center of convective activity and under the influence of a lower-troposphere cyclonic *** convective center was initiated in the west-central tropical Indian Ocean several days prior to the rainstorm in *** convective center first propagated eastward to the maritime continent,accompanied by the cyclonic circulation,and then moved northward to the northern South China Sea and South China,causing the rainstorms over *** addition,the westward propagation of convection from the tropical western Pacific to the southern South China Sea,as well as the propagation farther northward,intensified the convective activity over the northern South China Sea and South China during the first rainstorm.

关键词： convective activity propagation characteristics tropical Indian Ocean western Pacific

The Meta-Gaussian Bayesian Processor of Forecasts and Associated Preliminary Experiments

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Acta meteorologica Sinica 2013年第2期27卷 199-210页

作者：陈法敬矫梅燕陈静 National meteorological center China meteorological Administration

Public weather services are trending toward providing users with probabilistic weather forecasts, in place of traditional deterministic forecasts. Probabilistic forecasting techniques are continually being improved to optimize available forecasting information. The Bayesian Processor of Forecast （BPF）, a new statistical method for probabilistic forecast, can transform a deterministic forecast into a probabilistic forecast accord- ing to the historical statistical relationship between observations and forecasts generated by that forecasting system. This technique accounts for the typical forecasting performance of a deterministic forecasting sys- tem in quantifying the forecast uncertainty. The meta-Gaussian likelihood model is suitable for a variety of stochastic dependence structures with monotone likelihood ratios. The meta-Gaussian BPF adopting this kind of likelihood model can therefore be applied across many fields, including meteorology and hy- drology. The Bayes theorem with two continuous random variables and the normal-linear BPF are briefly introduced. The meta-Gaussian BPF for a continuous predictand using a single predictor is then presented and discussed. The performance of the meta-Gaussian BPF is tested in a preliminary experiment. Control forecasts of daily surface temperature at 0000 UTC at Changsha and Wuhan stations are used as the de- terministic forecast data. These control forecasts are taken from ensemble predictions with a 96-h lead time generated by the National meteorological center of the China meteorological Administration, the European Centre for Medium-Range Weather Forecasts, and the US National centers for Environmental Prediction during January 2008. The results of the experiment show that the meta-Gaussian BPF can transform a deterministic control forecast of surface temperature from any one of the three ensemble predictions into a useful probabilistic forecast of surface temperature. These probabilistic forecasts quantify the uncer

关键词： meta-Gaussian likelihood model BPF forecasting uncertainty probabilistic forecasting