Table of Content

28 April 2023, Volume 39 Issue 2 Previous Issue    Next Issue

Select

Characteristics of water vapor triggered by Typhoons Lekima and Krosa in Northeast China in 2019 Liang-chen MA, Hai-feng LIU, Bai-zhu SHEN, Hang-rui SUI, Ning WANG 2023, 39 (2):  1-10.  doi: 10.3969/j.issn.1673-503X.2023.02.001 Abstract ( 339 )   HTML ( 31 )   PDF (3017KB) ( 214 )   Save Using the reanalysis data of FNL (Final Reanalysis Data) and GDAS (Global Data Assimilation System) from the NCEP (National Center for Environmental Predictions), the precipitation data from China Meteorological Observation Network and the results of HYSPLIT (HYbrid Single-Particle Lagrangian Integrated Trajectory) model based on the Lagrange method, the water vapor conditions and transport process of a rainstorm triggered by a weakening typhoon in Northeast China from August 13 to 17, 2019 were analyzed.The results show that the water vapor in Northeast China is most closely related to the water vapor from the Western Pacific Ocean.Typhoon "Lekima" is the main water vapor supply system for this rainstorm, followed by Typhoon "Krosa".There are three main water vapor transport sources in the Lagrange method, which come from the western Pacific in the middle and low latitudes, respectively, corresponding to the Pacific and Yellow Sea in the Euler method.It originates from the South China Sea and corresponds to the Indian Ocean.Water vapor from northern Heilongjiang and northern China also plays a role in the rainstorm.The southern water vapor in the South China Sea and the western Pacific merge, which is the main water vapor supply for the rainstorm in Northeast China.The water vapor budget is mainly concentrated in the middle and lower layers, and the convergence zone of water vapor is mainly located between 700~900 hPa.The water vapor in the lower layer is transported vertically to the upper layer, and the stronger the water vapor convergence and vertical transport, the greater the precipitation.The water vapor inflow concentrates on the southern boundary of the lower layer, while the western and northern boundaries are generally the water vapor outflow boundary. Figures and Tables | References | Related Articles | Metrics

Select

Analysis of the formation and evolution of super tornado occurred in Kaiyuan of Liaoning province on July 3, 2019 Yu CHEN, Shi-teng CAO, Chuan-lei CHEN, Ying WANG, Yei YANG, Chao YUAN, Xue YANG, Chao JIANG, Qi-lin ZHANG, Man-li WU 2023, 39 (2):  11-19.  doi: 10.3969/j.issn.1673-503X.2023.02.002 Abstract ( 166 )   HTML ( 17 )   PDF (2571KB) ( 339 )   Save Based on multi-source observations with the high spatiotemporal resolution, synoptic situation, and environmental physical parameters, the formation and development mechanisms of an EF4-level strong tornado (Kaiyuan tornado for short) occurred in Kaiyuan of Liaoning province on July 3, 2019, were analyzed.The results show that the Kaiyuan tornado occurs in the southwest quadrant of the northeast cold vortex, on the south side of the 850 hPa shear line, and in the warm and humid environment of the southwest airflow on the ground.The temperature difference between ground and 925 hPa reaches 11 ℃, and the vertical lapse rate of the near-ground temperature is large.The system configuration has the characteristics of dry and cold above and warm and wet below.Under the influence of low level warm and wet air, the convective suppression energy is close to zero in the area around Kaiyuan, which is conducive to the occurrence of strong convective weather.Kaiyuan tornado appears in the rear end of the northeast cold vortex cloud system, and in the rapid growth period of convective cloud, it is in the northern boundary of the rapid cooling area.Doppler radar shows a typical supercell echo.The tornado appears at the top of the hook echo and the junction of updraft on the left of the strong echo gradient area. Figures and Tables | References | Related Articles | Metrics

Select

Optimization of hydro-meteorological simulation parameters in Yihe River Basin based on WRF-Hydro model Jun-jie LIU, Jin-lan GAO, Lei LIU, Yue-hong SHAO, Bi-wen WU, Zhi CHENG 2023, 39 (2):  20-27.  doi: 10.3969/j.issn.1673-503X.2023.02.003 Abstract ( 159 )   HTML ( 11 )   PDF (1311KB) ( 215 )   Save In order to optimize the parameter scheme suitable for WRF-Hydro hydro-meteorological forecast and simulation in the Yihe River Basin, the distribution calibration method was adopted to analyze several main hydrological parameters of WRF-Hydro model, which was driven by the China meteorological forcing dataset (CMFD) and precipitation data observed by the meteorological stations in the Yihe River basin.The flooding process caused by similar rainstorms was selected to carry out parameter fitting verification of the calibration results.The results show that the infiltration coefficient and surface roughness of the WRF-Hydro model have nonlinear characteristics on the yield flow.MannN roughness of the river has an obvious influence on both production flow and confluence velocity.The smaller the MannN roughness coefficient is, the faster the confluence speed is, the larger the production flow is and the earlier the peak occurrence time is.The infiltration coefficient and manning roughness are the most sensitive among all the measured parameters, especially in unsaturated soil.When the infiltration coefficient and MannN roughness multiplier are 1.5 and 0.7 respectively, and the default value of surface water holding depth and surface roughness is 1.0, the simulation effect of the runoff process is optimal. Figures and Tables | References | Related Articles | Metrics

Select

Comparative analysis of changes in atmospheric precipitable water during four short-time heavy rainfall processes in Shenyang from 2020 to 2021 Shuang XU, Peng-yu HU, Yue JIA, Jin-song CUI, Lei YANG, Chong LI, Dong-dong WANG, Wan-ting HOU 2023, 39 (2):  28-34.  doi: 10.3969/j.issn.1673-503X.2023.02.004 Abstract ( 199 )   HTML ( 19 )   PDF (2450KB) ( 224 )   Save Based on the ECMWF (European Center for Medium-Range Weather Forecasts) ERA5 reanalysis data, GPS (Global Position System) precipitable water vapor observations, and conventional observation data, the variation characteristics of atmospheric PWV (Precipitable Water Vapor) and water vapor flux during four short-time heavy rainfall processes from 2020-2021 under different weather systems in Shenyang were analyzed. The results show that the duration of water vapor accumulation is closely related to the corresponding weather system.PWV can be maintained at a relatively high level in the heavy rainfall process caused by the periphery of the subtropical high system, and the water vapor growth rate can reach 1.1 mm·h-1.In addition, the occurrence period of heavy rainfall corresponds with the peak of PWV, but the peaks of the two do not coincide completely.When short-time heavy rainfall occurs, the atmospheric precipitable water at Shenyang station reaches more than 38 mm.After the end of heavy rainfall, PWV weakens obviously. Figures and Tables | References | Related Articles | Metrics

Select

Comparison on the stable components between continuous and less fog and haze period in Beijing-Tianjin-Hebei region from 1979 to 2020 Shu-peng SUN, Lu ZHANG, Yang WU, Shan-jun CHENG, Guo-lin FENG 2023, 39 (2):  35-43.  doi: 10.3969/j.issn.1673-503X.2023.02.005 Abstract ( 130 )   HTML ( 10 )   PDF (3873KB) ( 106 )   Save Using NCEP/DOE reanalysis data during 1979-2020, the stable components of circulation in the Beijing-Tianjin-Hebei region of China were extracted based on the EOF decomposition method, and their spatial structure and evolution characteristics were compared.The results show that there is an obvious "tripole" structure in the stable component of the geopotential height field during the period of continuous haze in the Beijing-Tianjin-Hebei region, whereas the "tripole" structure shows an inverted phase distribution in the period of less fog and haze.The strong westerly anomaly and wave train in the middle and low latitudes of the wind field in Eurasia make the Beijing-Tianjin-Hebei region in a warmer state with less cold air activity, which is conducive to the maintenance of continuous haze.The Beijing-Tianjin-Hebei region is mostly in the period of less haze when Eurasia is characterized by significant meridional circulation.In the longer time scale (60 days), the "tripole" distribution situation still exists, providing a favorable circulation background for the continuous haze weather.The variation characteristics of the stable component indicate that the stable component has more obvious and better-sustained precursor signals in the early stage of the continuous haze weather than in the period of less fog and haze. Figures and Tables | References | Related Articles | Metrics

Articles

Select

Variations of ozone concentration and its influence factors in Changsha from 2016 to 2019 Rui-yang HUA,Wei LI,Cheng-zhi YE,Chang-jian NI 2023, 39 (2):  44-52.  doi: 10.3969/j.issn.1673-503X.2023.02.006 Abstract ( 153 )   HTML ( 17 )   PDF (1561KB) ( 149 )   Save Based on the hourly monitoring data of ozone, NO2, and CO in Changsha from 2016 to 2019 and the corresponding meteorological observation data, the temporal and spatial variations of ozone concentration and the meteorological influence factors were analyzed.The results show that the annual mean maximum 8-h moving average concentration of ozone in Changsha during 2016 and 2019 were (52.81±26.61) μg·m-3, (55.89±25.42) μg·m-3, (61.74±29.56) μg·m-3 and (60.77±31.68) μg·m-3, respectively, with an increasing trend.Ozone level is the highest in summer (mean 74.56 μg·m-3) and the lowest in winter (mean 33.64 μg·m-3).The diurnal variation in ozone presents a significant single-peak pattern with the peak level appearing at around 16:00 and the exceeding standard period between 12:00 and 18:00.The spatial heterogeneity in ozone shows that the levels appear larger at the urban periphery than at the urban center sites, with the largest heterogeneity in winter (0.12) and the smallest heterogeneity in summer (0.04).The concentrations of ozone in Changsha are positively correlated with temperature and solar radiation with the coefficients of 0.61 and 0.65, respectively, and negatively correlated with relative humidity, NO2, and CO with coefficients of -0.42, -0.35, and -0.27, respectively. Figures and Tables | References | Related Articles | Metrics

Select

Ozone pollution characteristics and the meteorology in the eastern urban agglomeration of Qinghai province from 2015 to 2018 Qi-yu XIE,Jing-mei LI,Qin ZHOU,Juan ZHAO,Xiao-ning GUO 2023, 39 (2):  53-61.  doi: 10.3969/j.issn.1673-503X.2023.02.007 Abstract ( 137 )   HTML ( 10 )   PDF (2347KB) ( 145 )   Save Based on daily air quality data, conventional meteorological observations, and ERA-Interim reanalysis data from 2015 to 2018, the characteristics of the ozone pollution process and its meteorological conditions in the eastern Qinghai urban agglomeration were analyzed.The results show that the maximum and minimum temperature, temperature dew point difference, sunshine duration, and total radiation are the positive influencing factors of ozone pollution in the eastern Qinghai urban agglomeration, among which the maximum temperature, temperature dew point difference, and total radiation influence the most significantly.Sea level pressure, 24-hour pressure, and temperature variation, total and low cloud cover are the negative impact factors, among which the sea level pressure and 24-hour temperature influence the most significantly.The surface weather system types on ozone pollution days mainly include low-pressure type, low-pressure front type, and pressure equalizing field type, among which the low-pressure front type and low-pressure type are the most conducive to the occurrence of ozone pollution process, which appear stable and not prone to be destroyed.On ozone pollution days, the surface layer is controlled by hot low pressure background, whereas the weak convection in the middle layer is inhibited by the stable air flow above, which is affected by the divergence circulation and subsidence movement (low-pressure type) due to the high-pressure center or ridge, rarely appearing vertical movement (low-pressure front type and even pressure type).Multiple inversion layers in the vertical direction, a significant dry zone in the ground layer, and lower wind speed on the whole provide favorable atmospheric stratification conditions for ozone pollution over the eastern Qinghai urban agglomeration. Figures and Tables | References | Related Articles | Metrics

Select

Characteristics and causes of short-duration extreme rainfall in Hainan Island from 2012 to 2021 Juan SHI, Xian-ling JIANG, Yuan-hui KE, Yan ZHENG 2023, 39 (2):  62-70.  doi: 10.3969/j.issn.1673-503X.2023.02.008 Abstract ( 260 )   HTML ( 19 )   PDF (3796KB) ( 296 )   Save Based on the hourly precipitation data and ERA5 high-resolution data from 323 surface meteorological stations in Hainan Island from 2012 to 2021, the temporal and spatial variations of regional short-duration extreme rainfall (SDER) in recent 10 years were analyzed statistically and the circulation background of SDER was discussed using the synthetic analysis method as well.The results show that there are about 422.3 times of SDER in Hainan Island per year, accounting for 8% of SDER.The seasonal and diurnal variations of SDER were significant, most of which occurred in the afternoon of April to October (14:00-19:00), and the SDER most occurred in August.In recent 10 years, there are at most 11 times of SDER at a station located in the northwest of Hainan Island.The diurnal variation of SDER appears unimodal and the peak appears at 17:00 with a frequency of 62.1 times per year.The mean intensity of SDER in the afternoon was higher, with an average of 67.8 mm·h-1 and a peak value of 111.5 mm·h-1.The spatial variation of SDER in the whole year and warm season appears in two high-incidence regions including the northwestern and eastern coastal areas of Hainan Island.The weather system in the warm season dominantly affects the SDER in Hainan Island.The monthly spatial variation differences of SDER in Hainan Island are closely related to land and sea breeze and topography.The triggering conditions are various for each month, and there is relatively more SDER from July to August. Figures and Tables | References | Related Articles | Metrics

Articles

Select

Frequency variation of winter low-temperature events in Guangxi and its response to Atlantic sea surface temperature from 1951 to 2020 Xiu-hua ZHOU,Yi TANG,Hong LU,Bing HAN 2023, 39 (2):  71-76.  doi: 10.3969/j.issn.1673-503X.2023.02.009 Abstract ( 121 )   HTML ( 2 )   PDF (1897KB) ( 159 )   Save The frequency of winter low-temperature events in Guangxi has obvious interannual and interdecadal variation characteristics from 1951 to 2020.In the early 1960s, it experiences an obvious mutation from less to more, and in the mid-1980s, it experiences a change from more to less.The period with a high frequency of low-temperature occurs from the middle of 1960s to the end of 1980s, and become less from the 1990s to the beginning of the 21st century.However, there are extreme years with unusually high frequency (such as 2008 and 2011) after the 2000s, which makes the frequency of low-temperature events show an upward trend.The frequency of low temperature in Guangxi has an interannual variation cycle of 2-5 years and an interdecadal cycle of about 10 years.Before 1990, the variation of low-temperature frequency is caused by the superposition of the above two main cycles, and then the signal of the cycle weakens, until 2005, the 2-5 years of the cycle appears again.The analysis results of the variation of winter low-temperature frequency in Guangxi and the East Asian monsoon and the Atlantic sea surface temperature show that the strong East Asian winter monsoon is conducive to the increase of low-temperature frequency in Guangxi.The Atlantic sea surface temperature in the west of Europe is abnormally low, and the circulation anomaly caused by the interaction of air and sea is the possible reason for the significant low temperature and the abnormal increase of low-temperature frequency in Guangxi. Figures and Tables | References | Related Articles | Metrics

Select

Analysis of the characteristics of low-temperature rain and snow in China from January to February in 2018 Yue WANG,Cheng-han LIU,Ji LI,Xiao FANG,Yu-tong WU,Jing-lin CUI,Jiao LI 2023, 39 (2):  77-83.  doi: 10.3969/j.issn.1673-503X.2023.02.010 Abstract ( 132 )   HTML ( 11 )   PDF (2530KB) ( 80 )   Save Using the daily NCEP/NCAR reanalysis data and the temperature data of the National Meteorological Information Center, the typical low-temperature rain and snow events in China from January 26 to February 4, 2018, were analyzed.The results show that before the occurrence of low-temperature rain and snow, the polar vortex begins to shrink to the west and gradually becomes elliptical.Affected by the abnormal enhancement of the polar vortex, the cold air is strengthened to the south.The high-pressure ridge forms about 15 days before the low-temperature rain and snow, and develops into a stable and powerful Siberian high-pressure over the Ural Mountains region, which continuously strengthened and moved eastward over the northern Eurasia continent.Two days before the occurrence of low-temperature rain and snow, two abnormally southerly air streams of 850 hPa wind field cooperate with the abnormal water vapor transport, and the positive anomaly of the geopotential height at 500 hPa of the upper Ural Mountains in the northeast-southwest direction and gradually weakened, resulting in the accumulation of a large amount of cold air in the abnormally strong cold center of Siberia and southward.It provides favorable conditions for the low-temperature rain and snow weather in China. Figures and Tables | References | Related Articles | Metrics

Select

Characteristics of convective cloud systems in the mountainous area of central Hainan province from 2016 to 2021 Feng-hua XING, Yan-bin HUANG, Guang-wei LI, Zhi-yuan MAO, Jie AO, Guang-rui HUANG, Qiao-ming HUANG 2023, 39 (2):  84-91.  doi: 10.3969/j.issn.1673-503X.2023.02.011 Abstract ( 104 )   HTML ( 13 )   PDF (2013KB) ( 184 )   Save Using dual-polarization radar data from March to September from 2016 to 2021, the spatiotemporal variation characteristics of convective cloud systems in the mountainous area of central Hainan province were analyzed.The results show that there are 951 cases of convective cloud systems in the mountainous area of central Hainan, accounting for 21.55% of the total number of convective cloud systems in the whole islands of Hainan province during the same period (4412).Among them, the warming high-pressure ridge and the South China Sea trough are relatively easy to cause convective cloud systems in the mountainous area of central Hainan province, 207 times and 189 times, respectively.March and April are the two months with the highest proportion of convective cloud systems in the mountains area of central Hainan province, both accounting for more than 30%.The main period of convective cloud systems in the mountainous area of central Hainan province is from 13:00 to 17:00, with 777 occurrences.The space of the convective cloud system in the central mountainous area mostly moves to the northeast and southeast, and the guiding air is mainly southwest and northwest.The most frequent cloud system moving velocity is 6~10 km·h-1 and 11~15 km·h-1, which are 306 times and 229 times respectively.The moving distance of the cloud systems is mainly concentrated in the 11~15 km and 16~20 km intervals, which are 26.5% and 19.2%, respectively.The typical case of convective cloud systems in the mountainous area shows an obvious "ZDR column" phenomenon at the early stage of the cloud systems, and the dual polarization phase relation value is low in the middle and low layers.There is a strong radar echo overhang in the middle of the cloud system. Figures and Tables | References | Related Articles | Metrics

Bulletins

Select

The study on the chilling injury warning index of typical greenhouse thermophilic vegetables in the central Shandong province Chen CHEN,Yan-chun CHEN,Zhi-qiang DONG,Zhi-wei ZHANG 2023, 39 (2):  92-99.  doi: 10.3969/j.issn.1673-503X.2023.02.012 Abstract ( 101 )   HTML ( 6 )   PDF (1207KB) ( 352 )   Save Based on the data on the inside and outside minimum temperature of a typical greenhouse in the central Shandong province from November of 2008 to March of 2021, combined with the chilling injury index of thermophilic vegetables, the correlation analysis, 80% guarantee rate safety method, and case analysis method were used to analyze the chilling injury warning index of the thermophilic vegetables under different weather conditions in different seasons.The results showed that there is no chilling injury in spring.In autumn, the chilling injury is mainly occurred in November and caused by less sunshine.A risk of light chilling injury can be released when the minimum temperature outside the greenhouse is below 0 ℃ under the condition of overcast days is more than 5 days, while the minimum temperature threshold value of the moderate chilling injury index is-5 ℃.The chilling injury in winter is divided into two types of low temperature or long-term overcast days, and its warning index is the minimum temperature outside the greenhouse.The chilling injury warnings under different weather conditions are divided into the following grades i.e.the light and moderate chilling injury under a clear day, cloudy weather, and overcast days with the duration ≤4 d and ≥5 d, and their minimum temperature threshold values are -7 ℃, -13 ℃, -6 ℃, -10 ℃, -4 ℃, -9 ℃, 0 ℃ and -7 ℃, respectively. Figures and Tables | References | Related Articles | Metrics

Select

Analysis of spatial and temporal changes of traffic accidents in road sections highly affected by severe weather conditions and their meteorological factors in Nagchu City Men YANG,Hua TIAN,Tsering DAWA,Ben-jun GUO 2023, 39 (2):  100-106.  doi: 10.3969/j.issn.1673-503X.2023.02.013 Abstract ( 122 )   HTML ( 7 )   PDF (1234KB) ( 135 )   Save Using the data on road traffic accidents caused by weather in Nagchu Municipality in Tibet from January of 2017 to June of 2020, as well as meteorological data from national-level meteorological stations near the accident sites, the grade and spatiotemporal distribution characteristics of the traffic accidents and their weather-related causes were analyzed.The results show that over the past three years, the weather-caused traffic accidents in Nagchu have been increasing year by year.The order of the ratio of weather conditions inducing traffic accidents from high to low is snow, rain, ice roads, hail, and fog.The number of traffic accidents features an obvious monthly and diurnal variation, and the time phase from 08:01 to 12:00 a.m.from December to next March is an accident-prone period.Accident-prone road sections are mainly the G109 Qinghai-Tibet Road.Increasing winter precipitation and decreasing average ground surface temperatures at 0 cm are the main meteorological reasons for the increase in the number of traffic accidents year by year. Figures and Tables | References | Related Articles | Metrics

Select

Analysis of suitable areas of four types of health-preserving climate in Chongqing based on the climate comfort index Yun-meng PENG,Yan-chuan ZHONG,Jun HE,Bai-cheng XIA,Ji ZHANG,Yuan-mou WANG,Kai-jia WANG 2023, 39 (2):  107-112.  doi: 10.3969/j.issn.1673-503X.2023.02.014 Abstract ( 119 )   HTML ( 12 )   PDF (1417KB) ( 120 )   Save Based on the daily meteorological data including average temperature, relative humidity, wind speed, and sunshine hours in Chongqing from the national meteorological sciences data center during 1980-2020, the climate comfort was calculated by adopting the temperature-humidity index and wind efficiency index.The spatial distribution characteristics of climate comfort and the suitable areas of the four types of health-preserving climate i.e.the all-season-mild, the summer resort, the winter hibernation, and the sunlight health-preserving in Chongqing area were analyzed using the Kriging interpolation method.Results indicate that the all-season-mild is concentrated in the northeastern and southeastern of Chongqing which are suitable for tourism, health care, and other health activities throughout the year.Chengkou has the most comfortable days in the year and is the most comfortable area in Chongqing.At the same time, the summer resort is focused on the southeast of Chongqing, such as Youyang, Xiushan, the south of Pengshui, and Qianjiang.Furthermore, most areas are suitable for hibernation except the southeastern of Chongqing.While the climate comfort level of sunlight recuperation shows the distribution of "high in the east and low in the west", that is, the suitable area of sunlight recuperation in the eastern area is more than in western Chongqing. Figures and Tables | References | Related Articles | Metrics