Table of Content

28 August 2025, Volume 41 Issue 4 Previous Issue   

Special section on the ‘8.20' extreme rainstorm in Huludao

Select

Causes of the “8·20” extraordinary rainstorm in Huludao and exploration of topographic effects LIU Chenghan, JIAO Haoran, ZHANG Aizhong, YAN Qi, LIU Shuo, DU Jiayi, SUN Yibo 2025, 41 (4):  1-9.  doi: 10.3969/j.issn.1673-503X.2025.04.001 Abstract ( 121 )   PDF (12254KB) ( 60 )   Save This study investigates the causes of the extreme rainstorm in Huludao,Liaoning Province during 19-20 August 2024 and the role of terrain,utilizing dense precipitation observations and ERA5 reanalysis data.Results show that the "east-high-west-low" circulation pattern formed by the Northeast Cold Vortex and the western Pacific subtropical high facilitated moisture transport via southerly flows along the subtropical high's western flank.The convergence between cold air from the vortex and warm-moist air from the subtropical high promoted Frontogenesis over western Liaoning.Terrain-front interactions intensified precipitation,as terrain-blocked flows in the western/northern frontal zone enhanced vertical motion.This uplift further amplified Frontogenesis through its effect on Tilted Items in the frontogenetic function,constituting a key dynamic mechanism.During peak rainfall,maximum precipitation occurred in a horn-shaped mountainous area where east/southeast flow over terrain converged with northeastward ascending flows,triggering mesoscale convective systems.The southward flow over slopes generated localized convergence through flow separation-reunion mechanisms,providing additional dynamic forcing.Prolonged frontal zone stagnation caused by orographically-induced ascent contributed to the event's exceptional duration. References | Related Articles | Metrics

Select

Application assessment of merged precipitation data during the “8·20” torrential rainstorm in Huludao XIAO Guangliang, CAI Kuizhi, WANG Ying, JI Yongming, LIU Jingnan, CHENG Pan, ZHU Xianlong, JI Ximeng 2025, 41 (4):  10-20.  doi: 10.3969/j.issn.1673-503X.2025.04.002 Abstract ( 86 )   PDF (4395KB) ( 24 )   Save The torrential rainstorm that occurred in the city of Huludao,Liaoning Province,on 20-21 August,2024 (referred to as the "8·20" torrential rainstorm) was selected. The applicability of five merged precipitation datasets (C3SPA_1km,C3SPA_5km,C2SPA_5km,C3SPA_1km_10m,L2SPA_1km_10m) in the extreme rainstorm is compared and evaluated by using hierarchical and non-hierarchical assessment under the conditions of complete and missing observation. The results show that five merged precipitation datasets underestimate the actual cumulative precipitation to varying degrees,with the level of short-term heavy precipitation increases,the underestimation of merged precipitation data increases. Among the five datasets,the 3-source 1km data and 3-source 5 km data have the best reconstructing ability under the conditions of complete observation,but their reconstructing ability decreased more significantly under missing observation condition.The 3-source 1 km data and 3-source 5 km data are significantly better than the 2-source 5 km data,the reconstructing ability of Liaoning 1km data is worse than that of the 3-source datasets,it is significantly better than that of the 2-source 5 km data.The nearest grid point may not always accurately reconstruct precipitation at a station,and there may be a more accurate precipitation value within 2 to 3 grids distances from the station. It is suggested that hourly merged precipitation product should be developed to improve assessments and reduce underestimation in observation blind areas. References | Related Articles | Metrics

Select

Applicability evaluation of multi-source fusion real-time interpolation station data in the “8·20” extraordinary precipitation process in Huludao SU Yumeng, ZHAI Qingfei, SHAN Weiwei, LUAN Yongming, REN Chuan, WANG Weiqi, PANG Zihao, LIU Jingnan 2025, 41 (4):  21-27.  doi: 10.3969/j.issn.1673-503X.2025.04.003 Abstract ( 81 )   PDF (1268KB) ( 17 )   Save The use of multi-source fusion grid real-time analysis products to interpolate missing station observation data can maintain the continuity of precipitation data.Selecting precipitation observation data from 39 faulty stations in Huludao from 05:00 on August 20,to 08:00 on August 24,2024 as the testing source,and using correlation analysis and other methods to evaluate and test the interpolation station data of multi-source fusion precipitation grid real-time products.The results showed that the proportion of real-time interpolation station data with precipitation observation errors within ±2 mm · h-1 was 83.12%.The multi-source fusion of real-time interpolation station data can accurately reflect the precipitation intensity of Huludao,achieving the expected goal.Among them,the interpolation results of Jianchang Bashhan Station are relatively the best,while the interpolation results of Jianchang Tangshenmiao Station are relatively the worst; The grading test results show that the interpolation results for precipitation intensity below 20 mm · h-1 are good,with 86.34% of the results having an error within ±2 mm · h-1.As the hourly precipitation intensity increases,the actual interpolation results for hourly precipitation deteriorate,and the interpolation results for extreme precipitation above 50 mm ·h-1 are relatively small. References | Related Articles | Metrics

ARTICLES

Select

The spatiotemporal distribution and environmental parameter characteristics of short-duration heavy rain in Liaoning under the background of Cold Vortex from 2017 to 2021 CAO Shiteng, YANG Lei, SUN Li, LU Juan, CHEN Yu, YANG Xue, JIANG Chao, LENG Yuxuan 2025, 41 (4):  28-38.  doi: 10.3969/j.issn.1673-503X.2025.04.004 Abstract ( 98 )   PDF (4418KB) ( 31 )   Save Based on hourly precipitation data from automatic weather stations in Liaoning Province and ERA5 reanalysis data from 2017 to 2021,the short-duration heavy rain (CV_SDHR) with hourly rainfall no less than 20 mm under the background of the Cold Vortex (CV) was selected and divided into different quadrants based on the relative position of the automatic weather stations and the 500 hPa potential height center of the CV.The highest occurrence frequency of CV centers lies between the eastern Inner Mongolia (110°～124°E) and the northern Heilongjiang(48°N),up to 58°N when CV_SDHR occurs.The spatiotemporal distribution and environmental parameter characteristics of SDHR in different quadrants were compared.The results show that CV_SDHR accounts for 35.7% of the total SDHR.The proportion of CV_SDHR in different quadrants decreases in the following order:southeast (SE_SDHR),southwest (SW_SDHR),northeast,and northwest quadrants.CV_SDHR with large hourly rainfall and wide impact range is mainly concentrated in the southeast and southwest quadrants of CV.The central and northern parts of Liaoning is a high-risk area for CV_SDHR.The stations dominated by SE_SDHR cover the Liaohe River Basin and coastal areas,while the stations dominated by SW_SDHR are concentrated in northern part of Liaoning.CV_SDHR exhibits monthly and daily variation characteristics with unimodal distribution.It mainly appears in the afternoon to evening from July to August,but with variations in different quadrants regarding the peak proportion,occurrence time,and duration.The similarity of CV_SDHR in different quadrants is that the temperature and humidity profiles are closer,the CAPE is narrower,and the wind field is conducive to the formation of vertical wind shear.The difference is that SE_SDHR often occurs in warmer and wetter environments,and has stronger and vertical wind shear,which is more conducive to the occurrence of stronger and larger range of CV_SDHR.The SW_SDHR appears in environments with dry water vapor,strong static instability,and lower relative humidity near the ground,making it more conducive to the simultaneous occurrence of multiple severe convective weathers. References | Related Articles | Metrics

Select

The Observation Characteristics of East Asia Geostationary Satellite Imager Data during Two Types of Rainstorm in Liaoning YANG Xue, YANG Lei, GENG Shibo, CAO Shiteng, SUN Li, JIANG Chao, CHEN Yu 2025, 41 (4):  39-47.  doi: 10.3969/j.issn.1673-503X.2025.04.005 Abstract ( 83 )   PDF (4368KB) ( 13 )   Save Four precipitation processes in the Liaoning Province under the background of the Cold Vortex and Subtropical High were analyzed,and the correlation between the infrared channel brightness temperature(center wavelength around 12.0 μm) and water vapor channel brightness temperature(center wavelength around 7.0 μm) of the FY-4B,ERA5 reanalysis,and automatic weather station data of the stationary meteorological satellites FY-4A,FY-4B,and H8/9(respectively referred to as FY-4B,FY-4B,and H8/9) was explored.Moreover,the observation characteristics and formation mechanism of precipitation clouds under different weather systems were compared and analyzed based on FY-4B,ERA5 reanalysis,and automatic weather station data.The analysis results are shown as follows.The correlation coefficient between FY-4B and H8/9 satellite data is significantly higher than that of FY-4A.For different levels of precipitation,the larger the 5-minute precipitation,the lower the brightness temperature of the infrared and water vapor channels of precipitation clouds,and the temperature difference between water vapor and infrared channels is also closer to 0 ℃.The infrared channel brightness temperature of strong precipitation clouds with a 5-minute rainfall greater than 10 mm are concentrated in below -40 ℃,and the temperature difference between water vapor and infrared channels of the strong precipitation clouds is within the range of -5 to 2 ℃.For precipitation of the same magnitude,the infrared channel brightness and water vapor channel brightness temperature of precipitation clouds under the influence of Cold Vortex are lower than those of precipitation clouds at the edge of the Subtropical High,and the temperature difference between water vapor and infrared channel brightness is also closer.Precipitation clouds of Cold Vortex generally appear in environments with strong static instability,strong vertical wind shear,and more dry and cold conditions.Due to the large difference in dew-point temperature at lower levels,the evaporation below the cloud base weakens precipitation more significantly.Therefore,for precipitation clouds with the same precipitation intensity,the infrared channel brightness temperature of precipitation clouds under Cold Vortex is lower than that of Subtropical High precipitation clouds.This research provides a reference for strengthening the comprehensive application of satellite data and improving rainstorm monitoring capability in the future. References | Related Articles | Metrics

Select

Cause analysis of a southwesterly airflow warm-sector heavy rainfall event in Henan LIANG Yu, HU Yanping, ZHANG Pu, ZHANG Yachun 2025, 41 (4):  48-57.  doi: 10.3969/j.issn.1673-503X.2025.04.006 Abstract ( 80 )   PDF (8418KB) ( 30 )   Save Based on meteorological observation,radar data,satellite data and NCEP 1°×1° reanalysis data every 6h,using the methods of synoptic analysis and physical quantity diagnosis,the occurrence and development mechanism of southwesterly airflow warm-sector heavy rainstorm in the Huanghuai region of Henan Province in July 2017 was analyzed.The results show that the mainly influence system of the heavy rainfall is the low and medium level jet.The unstable energy comes from the dry and cold upper layer with the warm and wet lower layer.The water vapor convergence and transport is mainly located near and below 850 hPa or 925 hPa.The strong water vapor convergence between the low level and near-surface,and the surface mesoscale convergence line are important triggering mechanisms for warm-sector heavy rainfall.The obviously dynamic frontogenesis provides a strong upward movement for heavy rainfall.The coupling of high and low level jet is the mainly dynamic strengthening mechanism.The heavy rainfall occurred in the gradient area of the high and low centers of TBB or near the center of lower TBB values,and the area of TBB lower than 220 K have an important indication significance for the heavy rainstorm area above 100 mm; The echo of heavy precipitation presents the characteristics of backward propagation and quasi-stationary,and the echo has warm cloud echo precipitation structure with low centroid meanwhile. References | Related Articles | Metrics

Select

Characteristics of a short-duration extreme heavy rainfall in Zhejiang Province based on S-band and X-band radar QIAN Zhuolei, ZHANG Chaoqin, SHEN Zhewen, ZHAO Chiyu 2025, 41 (4):  58-67.  doi: 10.3969/j.issn.1673-503X.2025.04.007 Abstract ( 80 )   PDF (12475KB) ( 26 )   Save Based on ERA5 reanalysis data,S-band dual-polarization radar and X-band dual-polarization phased array radar observation data,wind retrieval and lightning location data,the characteristics of local short-duration extreme heavy rainfall in Zhejiang on July 22,2023 were analyzed.Our results illustrate that: This event took place under the control of the subtropical high.The unstable stratification caused by the intrusion of cold dry air in the middle layer and the high energy and humidity in the lower layer provided the beneficial environment for the event.The initial linear convection occurred near the surface convergence line.The structure of the mesoscale convective system experienced from the single linear convection to the Connected double linear convection then to the separation.The development of ZDR and KDP columns indicate the strengthening of the convective system.When heavy rainfall occurs,the large areas of ZH,ZDR and KDP decrease rapidly,and the variation of rainfall intensity is closely related to KDP.The frequencies of cloud flash and negative ground flash significantly increase during heavy rainfall periods.The configuration of inclined updrafts and downdrafts is conducive to the development and maintenance of convective systems.The encounter of downdraft and ambient wind is benefit for the backward-propagation of convective system.Extreme heavy rainfall is also associated with the "train effect" and deep warm cloud layer. References | Related Articles | Metrics

Select

Characteristics of environmental fields and asymmetric precipitation at different stages of typhoon Khanun intensification WANG Han, LI Lan, TENG Fangda, TAN Zhenghua, ZHANG Mengmeng, LIN Zhongguan 2025, 41 (4):  68-78.  doi: 10.3969/j.issn.1673-503X.2025.04.008 Abstract ( 69 )   PDF (9112KB) ( 24 )   Save Using multi-source observational data,the study analyzes the environmental fields and the asymmetric precipitation characteristics during different intensification associated related stages of typhoon Khanun.The study compared and analyzed the environmental field characteristics of typhoon intensity changes at different stages from aspects such as sea surface temperature near the typhoon,evolution of upper-level and low-level circulations,moisture transport,and vertical wind shear.The results indicate that high sea surface temperatures near the typhoon center,dual outflows in the upper levels,continuous supply of summer monsoon moisture,and relatively small vertical wind shear between high and low levels provide favorable conditions for the rapid intensification of the typhoon.Generally,during the intensification process,there are conditions such as deteriorating sea surface temperatures,reduced upper-level outflow channels,disrupted moisture transport pathways,and increased vertical wind shear throughout the atmospheric layer.During the rapid intensification stage,periodic convective bursts occur within the typhoon's inner core region,with deep convection propagating from the downshear side to the upshear side.The convective region contracts toward the typhoon center.In contrast,during the general intensification stage,convective activity remains consistently on the left side of the environmental vertical wind shear,which is closely related to the asymmetric distribution of dynamic and thermal fields near the typhoon center. References | Related Articles | Metrics

Select

Study on the impact of cloud micro-physics schemes on the forecast of warm regions heavy rainfall XIE Zuxin, HUA Shaofeng, LIN Wen, LI Dan, YU Yongjing, FENG Hongfang 2025, 41 (4):  79-87.  doi: 10.3969/j.issn.1673-503X.2025.04.009 Abstract ( 70 )   PDF (8373KB) ( 12 )   Save WRFv3.7 model was applied to simulate the warm-sector precipitation process in the coast area of Fujian on May 7,2018.Five selected microphysics schemes all effectively indicated the location and amount of precipitation.The Thompson (THOM) and WDM6 schemes with better simulation results were selected to further analyze the characteristics and micro-physics mechanisms of cloud system.The results showed that the forecast of precipitation in the WDM6 scheme was better than that of the THOM scheme.These two schemes exhibited good consistency in simulating cloud macroscopic characteristics,liquid water content,and cloud sources and sinks.However,some differences existed in simulating ice water content:in the THOM scheme,ice-phase hydrometeor mainly consisted of snow (81.4%),graupel (4.8%),and a small amount of ice.In the WDM6 scheme,snow (29.7%) and graupel (33.3%) account for half of the total aqueous contents.In the THOM scheme,surface precipitation mainly originated from liquid processes within clouds,with rain collecting cloud water (58.7%) as the primary source,followed by snow melting (25.3%).In the WDM6 scheme,the main source of rain was the melting of graupel (67%),followed by the growth of rain collecting cloud water (18.4%). References | Related Articles | Metrics

Select

Spatiotemporal variation characteristics of snowstorm and assessment level of snowstorm process in Jilin Province from 1971 to 2020 LIU Yuxi, JIN Yujian, JI Lingling, LIU Ziqi, YUE Yuan, YAO Shuai 2025, 41 (4):  88-94.  doi: 10.3969/j.issn.1673-503X.2025.04.010 Abstract ( 75 )   PDF (1394KB) ( 14 )   Save Based on the data of daily precipitation,snow depth,extreme wind speed,maximum wind speed and minimum temperature of 55 national meteorological observation stations in Jilin Province from 1971 to 2020,then wavelet analysis,Mann-Kendall(M-K) mutation test,sliding T test and other methods were used to study and analyze the spatiotemporal variation characteristics of snowstorms in Jilin Province; the index of snowstorm process was established by grey correlation method,and divided to get the subregion’s assessment level index of snowstorm process in Jilin Province and validated.The results show that,the snowstorms in Jilin Province are mainly concentrated in November,then March,and both snowstorm stations and accumulated snowstorm amount show a significant steady upward trend,the increase rate is faster after 2006,and the most frequent is in the 2011-2020s; both snowstorm stations and accumulated snowstorm amount show a significant periodic change of 3a in 2000-2016; snowstorm stations change abruptly in 1987,and the average annual of snowstorm stations rose by 15.7 after the mutation; snowstorm stations and accumulated snowstorm amount both show a gradual increase in distribution from plain region to mountainous region; the snowstorm processes in the southeastern region are significantly more than that in the central and western regions,and the extra strong snowstorm processes are mostly distributed in the southeastern region; the subregional assessment level index of snowstorm process can reflect the comprehensive influence degree of snowstorm process in Jilin Province,which is of great significance to improve the ability of disaster prevention and mitigation in Northeast China and deal with extreme disastrous weather. References | Related Articles | Metrics

Select

Observations on micrometeorological and transport characteristics during dust events under the background of Northeast China Cold Vortex (NCCV) XIA Jiaqi, XU Shuang, LI Xiaolan, LI Liguang, SHEN Lidu, ZHAO Hujia, WANG Dongdong, ZHOU Chunxiao 2025, 41 (4):  95-103.  doi: 10.3969/j.issn.1673-503X.2025.04.011 Abstract ( 87 )   PDF (7417KB) ( 24 )   Save Northeast China Cold Vortex (NCCV) is one of the important weather systems affecting Northeast China.However,there is still limited understanding on the formation and transport characteristics of dust events under the NCCV background.Using the three-dimensional synchronous observational data of meteorological elements and dust parameters in Shenyang in the spring of 2023,combined with backward trajectory analysis,we analyze the characteristics of micrometeorological conditions and dust transport and reveal the impacts of near-surface turbulence during three dust events of different intensities under the influence of the NCCV.The results show that affected by the NCCV,near-surface turbulence activity was vigorous before the occurrence of dust events.The cold vortex system induced precipitation and made the ambient humidity increase,which is different from dust events without the influence of the NCCV.During the dust emission stage of the two blowing-sand events,the lower atmosphere was thermally unstable,and the dust concentration increased significantly with the enhancement of friction velocity (u*) and turbulence kinetic energy,mainly due to local dust emission.In the later stage of the blowing-sand event on 11 April,affected by weak winds and high humidity environment,the proportion of fine particulate matter (PM2.5) increased,and dust-haze pollution coexisted.Compared with blowing sand events,the atmospheric stratification was stable during dust emission stage of the floating dust event,and there was no significant synchronous variation relationship between u* and dust concentration near the surface,meaning dust transport from external sources.The results of the backward trajectory analysis showed that the three dust events were all influenced by dust external sources to varying degrees.Massive dust aerosols were transported to Northeast China by the upper-level northwesterly airflow through Mongolia and other places,with the aerosol transport height concentrated between 1.0 and 1.5 km. References | Related Articles | Metrics

Select

Quantitative assessment and spatial-temporal characteristics of regional rainstorm process in Heilongjiang Province ZHANG Hongling, ZHU Hongrui, XU Yongqing, LIU Henan 2025, 41 (4):  104-109.  doi: 10.3969/j.issn.1673-503X.2025.04.012 Abstract ( 60 )   PDF (1644KB) ( 8 )   Save Based on the daily precipitation data of 71 national ground observation stations in Heilongjiang Province from 1961 to 2020,the criteria for determining regional rainstorm processes are defined.The maximum process precipitation,maximum daily precipitation,process range,maximum range of a single day and duration of a rainstorm process are selected as evaluation indicators to build a comprehensive evaluation model for regional rainstorm processes,and analyze the spatial and temporal distribution characteristics of regional rainstorm,And quantitatively evaluate it.The results show that:A total of 123 regional rainstorm events occurred in Heilongjiang Province,showing a significant upward trend,mainly in July and August from 1961 to 2020,and 91.1% of the process lasted for one day;The rainfall centers are mainly concentrated in the southern part of Yichun,most of Harbin,the southern part of Mudanjiang,the central part of Jixi,and the western part of Suihua;The comprehensive intensity in the 1990s and the past decade was the highest,with weak,moderate,strong,stronger,and extremely strong grade processes accounting for 66%,17%,9%,4%,and 4%;In recent ten years,the intensity and frequency of extra-strong processes are more prominent,and they are greatly affected by northward typhoons. References | Related Articles | Metrics

Select

Precipitation prediction during the Meiyu period over central Zhejiang Province based on the interannual increment method WANG Ziqi, XU Yejia, WANG Fang, YE Yanting, GONG Junqiang 2025, 41 (4):  110-116.  doi: 10.3969/j.issn.1673-503X.2025.04.013 Abstract ( 59 )   PDF (1583KB) ( 7 )   Save In this study,the precipitation variation characteristics during the Meiyu period over central Zhejiang Province from 1979 to 2022 are analyzed based on the daily precipitation observation fromeightnational meteorological stations in Jinhua City of Zhejiang Province,and the dataset of 88 circulation indexes and 26 sea surface temperature indexes compiled by the National Climate Center of China.Then,five key climate prediction factors have been selected by using the interannual increment method and correlation analysis,namely the NINO 1+2 sea surface temperature anomaly(SSTA) index in April,the NINO B SSTA index in March,the North American-North Atlantic subtropical high intensity index in August of the previous year,and the Oyashio current sea surface temperature index in December of the previous year,the North Pacific pattern index in February.Furthermore,based on the above five factors and the multiple regression method,an interannual increment prediction model for Meiyu precipitation in central Zhejiang is established.Cross-validation tests are performed to validate the precipitation prediction.Results show that the correlation coefficient between observation and the prediction by interannual increment method is 0.8,and the symbol consistency rate is 79%.The interannual increment prediction resultsare converted to precipitation anomaly percentages,which are checked by the PS score.The model can well predict the precipitation anomaly in Meiyu period,with a PS score of 88.5 in the past 1980-2022's leave-one-out cross-validation. References | Related Articles | Metrics

Select

Analysis of meteorological conditions for transmission line wind damage in Shijiazhuang area ZHANG Cuihua, LIU Siting, FENG Yang 2025, 41 (4):  117-124.  doi: 10.3969/j.issn.1673-503X.2025.04.014 Abstract ( 69 )   PDF (956KB) ( 12 )   Save In order to study and determine the meteorological conditions of transmission line wind damage accidents in Shijiazhuang area,,surface meteorological observations,high resolution fusion live data,upper-air circulation situation field data,radiosonde data and the detailed data of transmission line wind damage accidents at the time of occurrence from 2004 to 2021 were used to analyze the spatio-temporal changes of transmission line wind damage accidents by using climatic statistical methods,weather principles and ArcGis and sufer software,the weather reality characteristics and weather system configuration and radiosonde physical quantities index which were prone to transmission line wind damage accidents were summarized and determined.The forecast accuracy of transmission lines wind damage accidents from 2022 to 2023 was tested by the meteorological conditions of transmission lines wind damage accidents.The results show that,transmission line wind damage accidents are mainly foreign body short-circuit in Shijiazhuang area,which are mainly distributed in the surrounding counties as the center of the main urban area including Gaocheng,Xinle,Zhengding,Luancheng,Jingxing,which mainly occur in the daytime of spring and summer,concentrating from noon to evening,and the frequency of line breakage,wind deviation,tower toppling,and conductor galloping is very small.When the transmission line wind damage accidents occur,the diurnal maximum dominant wind direction of foreign body short-circuit,line breakage and tower toppling is the northwest wind,the diurnal maximum dominant wind direction of wind deviation is the westerly wind,and the diurnal maximum dominant wind direction of conductor galloping is the northeast wind.The benchmark wind force of line breakage,wind deviation and tower toppling is larger,the benchmark wind force of foreign body short-circuit and conductor galloping is smaller.The meteorological conditions of the transmission line wind damage accidents had been well predicted and tested from 2022 to 2023,which had certain guiding significance for the local power department to prevent lightning strike accidents. References | Related Articles | Metrics

Select

Characterization of spatial and temporal distribution of human comfort in summer in Hebei Province based on UTCI LIU Siting, YANG Ye, BIAN Tao, ZHANG Cuihua 2025, 41 (4):  125-135.  doi: 10.3969/j.issn.1673-503X.2025.04.015 Abstract ( 70 )   PDF (8834KB) ( 15 )   Save Based on the daily data from 143 national-level surface meteorological observation stations in Hebei Province during the summer months from 1991 to 2020,as well as the daily data from 8 radiation stations from 2014 to 2020,this study takes the Universal Thermal Climate Index (UTCI) as the evaluation indicator.It reveals the spatiotemporal distribution pattern of summer human thermal comfort using trend analysis and Kriging interpolation methods.The results show that over the past 30 years,the proportion of comfortable days in Hebei Province during summer has generally shown a decreasing trend,with a trend value of -0.9% per decade.There are spatial differences: as the altitude decreases,the tendency rate of the proportion of comfortable days shifts from positive to negative.The proportion of comfortable days in plains,hills,and low mountainous areas presents a single-valley pattern,while high-altitude areas show a single-peak pattern.The number of summer comfortable days in these four types of terrain is 24,81,92,and 92 days respectively,with low mountainous and high-altitude areas having comfortable days throughout the entire summer season.In terms of spatial distribution,there is an overall decreasing trend from northwest to southeast.High-altitude areas have the highest proportion of comfortable days,reaching 95.6%,while plains have the lowest proportion at 33.8%.High-altitude areas have the highest proportion of comfortable days in July and August.However,in June,due to the still relatively low temperatures in high-altitude areas,low mountainous areas have the highest proportion of comfortable days.Therefore,low mountainous and high-altitude areas in Hebei Province have a comfortable summer thermal sensation and are suitable for traveling.The plains are suitable for traveling in the first and middle ten days of June,and the hills are suitable for traveling except in the last ten days of July. References | Related Articles | Metrics

BULLETINS

Select

Risk analysis of frost damage in Dandong blueberry flowering period in Liaoning Province DONG Haitao, LI Runan, SHAN Lulu, MENG Xi, FANG Yihe 2025, 41 (4):  136-145.  doi: 10.3969/j.issn.1673-503X.2025.04.016 Abstract ( 73 )   PDF (4315KB) ( 12 )   Save Based on the meteorological monitoring data of blueberry (Vacciniumset.Cyanococcus) flowering period in four meteorological observation stations (and three surrounding meteorological observation stations) in Dandong area from 1991 to 2020,the temporal variation characteristics of minimum temperature were analyzed by mathematical statistics method.The daily minimum temperature Tmin≤1 ℃ of blueberry flowering period was taken as the index of spring frost grade of blueberry.The risk index of spring frost disaster in blueberry flowering period was constructed and evaluated by four parameters :climate probability,standard deviation,occurrence frequency and intensity of spring frost.The results showed that:The climate tendency rate of the average minimum temperature during the flowering period of Dandong blueberries in the past 30 years showed an overall upward trend,with an average increase of 0.04 ℃ every 10 years.Among them,Fengcheng and Kuandian areas showed a downward trend,while Zhen'an and Donggang stations showed an upward trend.The northern mountainous area was more conducive to the formation of spring frost.The number of spring frost days during the flowering period of Dandong blueberry in the past 30 years showed an increasing trend,among which the number of mild spring frost days was up to 19.5 d (moderate 1.0 d,severe 0.8 d),and the climate tendency rate was more moderate and severe.The increasing trend was significant,with an average increase of 0.2 d per 10 years,mainly occurring in the Kuandian area of the northeastern mountainous area.The climatic probability of spring frost in Dandong blueberry flowering period in 30 a was significantly higher in the northern mountainous area (probability range 70.0%-86.6%) than in the southern coastal area (3.5%-10.1%),and the spatial distribution characteristics were basically consistent with the frequency and intensity of spring frost.The spring frost disaster risk index of Dandong blueberry flowering period can be divided into five grades:none,low,medium,high and extremely high risk.The extremely high and high risk areas are mainly concentrated in most areas of Kuandian and northern Fengcheng.The medium-risk areas are mainly concentrated in most areas of Fengcheng ;the low-risk areas are mainly concentrated in the south of Fengcheng and the north of Donggang,while the risk-free areas are mainly concentrated in Zhen'an District and the east of Donggang,which is consistent with the spatial distribution of the actual blueberry planting base.The results of the study obtained the risk areas of different levels of blueberry flowering spring frost disaster in each region,and provided a reference for scientific response to the blueberry flowering spring frost disaster. References | Related Articles | Metrics

Select

Quantitative evaluation for microclimate suitability of watermelon in solar greenhouse ZHAO Hua, GAO Xiaomei, LI Shujun, YUAN Jing, FENG Yaqiong 2025, 41 (4):  146-152.  doi: 10.3969/j.issn.1673-503X.2025.04.017 Abstract ( 51 )   PDF (967KB) ( 10 )   Save using experimental observation data of watermelon (Citrullus Lanatus) in solar greenhouse in Weifang Facility agricultural wisdom meteorological Service Demonstration Site from 2019 to 2021,based on fuzzy mathematical theory,a comprehensive suitability quantitative evaluation model and evaluation index of five factors,including air temperature,air humidity,solar radiation,ground temperature and temperature daily range,were established.The historical microclimate conditions of watermelon in solar greenhouse from 2019 to 2021 were evaluated and analyzed.The actual yield and quality of watermelon samples and typical disaster weather process were used to verify the applicability of the model and evaluation index.The results showed that the goodness of fit (R2) of the five-factor comprehensive microclimate suitability index and the comprehensive quality index is 0.6107,which is significantly better than the goodness of fit (R2) of the four-factor comprehensive microclimate suitability index and the comprehensive quality index (0.4079).The suitability model and evaluation index established in this study can well represent the suitability of microclimate environment during the growth and development of watermelon in solar greenhouse.The microclimate suitability of watermelon in solar greenhouse generally increased with growth and development,and the microclimate suitability of watermelon in solar greenhouse was higher in formation stage to maturity stage,but lower in transplanting stage and seedling stage. References | Related Articles | Metrics

Select

Analysis of Climate Suitability Changes for Soybean Cultivation in Liaoning Province ZHANG Wei, MIN Kuangnan, ZHANG Shujie, CHEN Nina, JIANG Shan, WANG Xuemeng, LI Danlin 2025, 41 (4):  153-160.  doi: 10.3969/j.issn.1673-503X.2025.04.018 Abstract ( 66 )   PDF (2727KB) ( 7 )   Save Liaoning Province,a key soybean-producing and climate-sensitive region in China,is increasingly affected by climate change on soybean cultivation.This study investigates the impact of climatic variability on soybean climatic suitability by analyzing meteorological and phenological data from 52 weather stations across the province.The analysis compares the recent climatic normal (1991-2020) with the previous period (1981-2010),using a comprehensive climatic suitability model that integrates temperature,precipitation,and sunshine duration to evaluate spatiotemporal changes.Results show that 94% of regions experienced improved temperature suitability during the growing season,with statistically significant increases in half of these areas.In contrast,61% of regions exhibited a decline in precipitation suitability,while sunshine suitability presented mixed trends,with 50% of areas showing improvement and 50% showing deterioration.Overall,65% of regions demonstrated enhanced comprehensive climatic suitability,shifting from a non-significant decline under the old normal to a non-significant upward trend under the new normal,with favorable conditions expanding across most of Liaoning.Among the three climatic factors,sunshine duration contributed most significantly to overall suitability,followed by temperature and precipitation.In conclusion,although precipitation suitability declined and sunshine suitability exhibited equal proportions of improvement and deterioration,the overall climatic suitability for soybean cultivation in Liaoning has improved,largely due to increased temperature suitability.Strategic expansion of soybean cultivation,tailored to regional climatic characteristics and meteorological risks,is recommended to strengthen production resilience under future climate scenarios. References | Related Articles | Metrics