Climatology of Hail in China: 1961–2005

2008 ◽  
Vol 47 (3) ◽  
pp. 795-804 ◽  
Author(s):  
Chunxi Zhang ◽  
Qinghong Zhang ◽  
Yuqing Wang
Keyword(s):  
Southern China ◽  
Northern China ◽  
Western China ◽  
Mountainous Areas ◽  
Comprehensive Collection ◽  
Central Tibetan Plateau ◽  
Seasonal And Diurnal Variations ◽  
Information Center ◽  
The Mean ◽  
Made In

Abstract A previous hail climatology of China was based upon observations during 1951–60. An effort has been made in this study to update this hail climatology in China with the use of a much longer record of observations from 1961 to 2005. This is made possible with the release of a new, comprehensive collection of hail observational data in May 2006 by the National Meteorological Information Center of China. The focus herein is to document the mean annual geographical distribution of hail frequency and seasonal and diurnal variations of hail occurrence. The results show that hail occurs most frequently in the high mountainous areas and northern plains. As a result, hail frequency is generally higher in northern China than in southern China. The hail frequency is highest over the central Tibetan Plateau. Hail seasons start in late spring and end in early autumn in northern and western China; they start mainly in spring in southern and southwestern China. On the diurnal time scale, hail events occur mainly between 1500 and 2000 local time in most of China except in Guizhou and Hubei Provinces (central western China), where hail events often occur during nighttime.

scholarly journals Responses of runoff to historical and future climate variability over China

2017 ◽  
Author(s):  
Chuanhao Wu ◽  
Bill X. Hu ◽  
Guoru Huang ◽  
Peng Wang ◽  
Kai Xu
Keyword(s):  
Climate Variability ◽  
Arid Regions ◽  
Southern China ◽  
Aridity Index ◽  
Global Climate Models ◽  
Future Climate ◽  
Western China ◽  
Climate Projections ◽  
Positive Contribution ◽  
The Mean

Abstract. China has suffered some of the effects of global warming, and one of the potential implications of climate warming is the alteration of the temporal-spatial patterns of water resources. Based on the long-term (1960–2012) water budget data and climate projections from 28 Global Climate Models (GCMs) of the Coupled Model Intercomparison Project Phase 5 (CMIP5), this study investigated the responses of runoff (R) to historical and future climate variability in China at both grid and catchment scales using the Budyko-based elasticity method. Results show that there is a large spatial variation in precipitation (P) elasticity (from 1.2 to 3.3) and potential evaporation (PET) elasticity (from −2.3 to −0.2) across China. The P elasticity is larger in northeast and western China than in southern China, while the opposite occurs for PET elasticity. The catchment properties elasticity of R appears to have a strong non-linear relationship with the mean annual aridity index and tends to be more significant in more arid regions. For the period 1960–2012, the climate contribution to R ranges from −2.4 % a−1 to 3.3 % a−1 across China, with the negative contribution in the North China plain and the positive contribution in western China and some parts of the southwest. The results of climate projections indicate that although there is large uncertainty involved in the 28 GCMs, most project a consistent change in P (or PET) in China at the annual scale. For the period 2071–2100, the mean annual P will likely increase in most parts of China, especially the western regions, while the mean annual PET will likely increase in all of China, particularly the southern regions. Furthermore, greater increases are projected for higher emission scenarios. Overall, due to climate change, the arid regions and humid regions of China will likely become wetter and drier in the period 2071–2100, respectively (relative to the baseline 1971–2000).

scholarly journals Occurrence and source apportionment of perfluoroalkyl acids (PFAAs) in the atmosphere in China

2019 ◽  
Vol 19 (22) ◽  
pp. 14107-14117 ◽  
Author(s):  
Deming Han ◽  
Yingge Ma ◽  
Cheng Huang ◽  
Xufeng Zhang ◽  
Hao Xu ◽  
...  
Keyword(s):  
Degradation Products ◽  
Southern China ◽  
Eastern China ◽  
Northern China ◽  
Central China ◽  
Western China ◽  
Perfluoroalkyl Acids ◽  
Average Value ◽  
Pmf Model ◽  
Air Sampler

Abstract. Perfluoroalkyl acids (PFAAs) are a form of toxic pollutant that can be transported across the globe and accumulated in the bodies of wildlife and humans. A nationwide geographical investigation considering atmospheric PFAAs via a passive air sampler (PAS) based on XAD (a styrene–divinylbenzene copolymer) was conducted in 23 different provinces/municipalities/autonomous regions in China, which provides an excellent chance to investigate their occurrences, spatial trends, and potential sources. The total atmospheric concentrations of 13 PFAAs (n=268) were 6.19–292.57 pg m−3, with an average value of 39.84±28.08 pg m−3, which were higher than other urban levels but lower than point source measurements. Perfluorooctanoic acid (PFOA) was the dominant PFAA (20.6 %), followed by perfluorohexanoic acid (PFHxA), perfluorooctane sulfonate (PFOS), and perfluoroheptanoic acid (PFPeA). An increasing seasonal trend of PFAA concentrations was shown as summer < autumn < spring < winter, which may be initiated by stagnant meteorological conditions. Spatially, the content of PFAAs displayed a declining gradient trend of central China > northern China > eastern China > north-eastern China > south-western China > north-western China > southern China, and Henan contributed the largest proportion of PFAAs. Four sources of PFAAs were identified using a positive matrix factorization (PMF) model, including PFOS-based products (26.1 %), products based on PFOA and perfluorononanoic acid (PFNA; 36.6 %), degradation products of fluorotelomer-based products (15.5 %), and an unknown source (21.8 %).

scholarly journals Prevalence of Corneal Astigmatism in Patients before Cataract Surgery in Western China

2020 ◽  
Vol 2020 ◽  
pp. 1-6
Author(s):  
Wei Ma ◽  
Chengguo Zuo ◽  
Weirong Chen ◽  
Shaoyang Zheng ◽  
Jiangang Xu ◽  
...  
Keyword(s):  
Cataract Surgery ◽  
Southern China ◽  
Cross Sectional Study ◽  
Corneal Astigmatism ◽  
Partial Coherence ◽  
Western China ◽  
Cross Sectional ◽  
Autonomous Region ◽  
Xinjiang Uygur Autonomous Region ◽  
The Mean

Purpose. To investigate the demographics and distribution of corneal astigmatism before cataract surgery in patients from western China and to compare and analyze these findings with those of patients in southern China. Setting. People’s Hospital of Xinjiang Uygur Autonomous Region. Design. Clinical-based cross-sectional study. Methods. Patients undergoing cataract surgery in the People’s Hospital of Xinjiang Uygur Autonomous Region from February 2012 to August 2019 were recruited. Preoperative keratometric data measured by performing preoperative bilateral partial coherence interferometry (IOLMaster), and patient demographics were recorded and analyzed. Results. This study comprised 12,236 eyes of 7065 patients with a mean age of 64.75 ± 9.66 years, and 52.77% of the patients were female. The mean axial length was 23.14 ± 0.96 mm. Astigmatism ranged from 0 diopters (D) to 6.94 D, with a mean of 1.28 D. Corneal astigmatism was between 0.25 D and 1.25 D in 53.71% of eyes, 1.25 D or higher in 39.06% eyes, and less than 0.25 D in 7.23% of eyes. Astigmatism was with the rule (WTR) in 41.94% of the patients and against the rule (ATR) in 38.80% of patients. The mean flat and steep keratometry measurement was 43.19 ± 1.50 D and 44.24 ± 1.62 D, respectively. After matching, corneal astigmatism in western China was 1.30 ± 1.03 D, and it was significantly higher than that in southern China (0.98 ± 0.67 D, P<0.001). After matching, the proportion of WTR astigmatism was 40.99% in western China, which was also significantly higher than the proportion (26.46%) in southern China (P<0.001). Conclusion. Corneal astigmatism in patients before cataract surgery in western China was mainly between 0.25 D and 1.25 D. Compared with patients in southern China, patients in western China are younger, have a much higher degree of astigmatism, and have a higher proportion of WTR astigmatism.

scholarly journals Characteristics of trace gaseous pollutants at a regional background station in Northern China

2008 ◽  
Vol 8 (3) ◽  
pp. 9405-9433 ◽  
Author(s):  
Z. Y. Meng ◽  
X. B. Xu ◽  
P. Yan ◽  
G. A. Ding ◽  
J. Tang ◽  
...  
Keyword(s):  
Trace Gases ◽  
Northern China ◽  
Gaseous Pollutants ◽  
Present Measurement ◽  
Back Trajectories ◽  
Air Masses ◽  
Seasonal And Diurnal Variations ◽  
Measurement Results ◽  
Regional Air Quality ◽  
The Mean

Abstract. We present measurement results of trace gaseous pollutants obtained at the Shangdianzi (SDZ) Global Atmosphere Watch (GAW) regional station in Northern China, from September 2003 to December 2006. The gases include ozone (O3), nitrogen oxide(s) (NOx=NO+NO2), sulfur dioxide (SO2), and carbon monoxide (CO). During the study period, the mean annual O3 concentrations were 30.1±21.0, 32.8±19.1 and 30.9±19.8 ppbv in 2004, 2005 and 2006. The corresponding NOx values were 14.5±14.0, 11.0±11.3 and 12.7±11.8 ppbv, respectively. The mean annual SO2 concentrations were 5.9±10.0, 6.1±9.9 and 7.6±10.2 ppbv in 2004, 2005 and 2006, while the mean CO levels were 586±415 and 742±558 ppbv in 2005 and 2006. The data obtained at SDZ station are compared with the results measured at other background sites in China as well as abroad. The concentrations of O3, NOx, SO2, and CO at the SDZ background station are found to have clear seasonal and diurnal variations. The impacts of local and remote pollution sources on the regional air quality are assessed using trace gases concentration roses and 3-day back trajectories of air masses arriving at the SDZ station.

scholarly journals Prevalence and Epidemiologic Analysis of Porcine Circovirus Type 2 in China from 2013 to 2015

2016 ◽  
Vol 5 (1) ◽  
pp. 1 ◽  
Author(s):  
Yuzhang Sun ◽  
Yonglian Dai ◽  
Renfu Yin
Keyword(s):  
Southern China ◽  
Eastern China ◽  
Northern China ◽  
Wide Distribution ◽  
Porcine Circovirus Type ◽  
Western China ◽  
Porcine Circovirus ◽  
Effective Measure ◽  
Available Information

<p>Previous studies have indicated a wide distribution of PCV-2 in China , there is no available information on the current PCV-2 prevalence and Epodemilogic analysis all over the country. In this study, the result showed that prevalence of PCV-2 in Eastern China (87.3%) was significantly higher than Western China (47.6%), PCV-2b 1A/1B and 1C stains were isolated from the farms in Northern China, whereas PCV-2b 1C stains were epidemic in Southern China. Moreover, this study provided the positive and effective measure to control this disease in the long term.</p>

An Analysis of Cloud-to-Ground Lightning in China during 2010–13

2015 ◽  
Vol 30 (6) ◽  
pp. 1537-1550 ◽  
Author(s):  
Xinlin Yang ◽  
Jianhua Sun ◽  
Wanli Li
Keyword(s):  
Southern China ◽  
Eastern China ◽  
Warm Season ◽  
Temporal Distribution ◽  
Cold Season ◽  
Western China ◽  
Southeastern China ◽  
The Mean ◽  
High Elevations ◽  
Cg Lightning

Abstract The cloud-to-ground (CG) lightning data being detected by the China Lightning Detection Network between 2010 and 2013 are employed to gain insight into the spatial and temporal distribution of CG lightning in China. There are clear interannual and seasonal variations of CG lightning activity. The mean total CG and positive CG (PCG) flashes in 2010–13 are approximately 6.44 million and 0.42 million, respectively, and the mean percentage of PCG (PPCG) is 6.6%. CG and PCG flashes predominately occur during summer, with August being the peak month for CG and June for PCG. PPCG in the cold season is considerably greater than in the warm season; its maximum of 56.2% is in January and the minimum value of 4.0% is found in August. The centers of maximum mean annual CG density are scattered throughout southern China, the Sichuan basin, and the south of Jiangsu Province. The CG density in the high elevations and arid regions of western China is less than that in the low elevations and coastal regions of southeastern China. In addition, daily CG density and CG lightning days in southeastern China are greater than in northwestern China, but PPCG in western China is apparently greater than that in eastern China. Areas experiencing more than 30 CG lightning days per year are primarily south of 30°N, with 10–30 lightning days per year in northern and northeastern China, and approximately 10–20 lightning days per year over the central Tibetan Plateau.

Spatial variation of East Asian winter monsoon evolution between northern and southern China since the last glacial maximum

2021 ◽  
pp. 1-14
Author(s):  
Qin Li ◽  
Haibin Wu ◽  
Jun Cheng ◽  
Shuya Zhu ◽  
Chunxia Zhang ◽  
...  
Keyword(s):  
East Asian Winter Monsoon ◽  
Southern China ◽  
Ice Sheets ◽  
Northern China ◽  
Winter Monsoon ◽  
Asian Winter Monsoon ◽  
Spatial Differences ◽  
The Last Glacial Maximum ◽  
The Last Glacial

Abstract The East Asian winter monsoon (EAWM) is one of the most dynamic components of the global climate system. Although poorly understood, knowledge of long-term spatial differences in EAWM variability during the glacial–interglacial cycles is important for understanding the dynamic processes of the EAWM. We reconstructed the spatiotemporal characteristics of the EAWM since the last glacial maximum (LGM) using a comparison of proxy records and long-term transient simulations. A loess grain-size record from northern China (a sensitive EAWM proxy) and the sea surface temperature gradient of an EAWM index in sediments of the southern South China Sea were compared. The data–model comparison indicates pronounced spatial differences in EAWM evolution, with a weakened EAWM since the LGM in northern China but a strengthened EAWM from the LGM to the early Holocene, followed by a weakening trend, in southern China. The model results suggest that variations in the EAWM in northern China were driven mainly by changes in atmospheric carbon dioxide (CO2) concentration and Northern Hemisphere ice sheets, whereas orbital insolation and ice sheets were important drivers in southern China. We propose that the relative importance of insolation, ice sheets, and atmospheric CO2 for EAWM evolution varied spatially within East Asia.

scholarly journals Development of revised diagnostic criteria for Fuchs’ uveitis syndrome in a Chinese population

2021 ◽  
pp. bjophthalmol-2021-319343
Author(s):  
Peizeng Yang ◽  
Wanyun Zhang ◽  
Zhijun Chen ◽  
Han Zhang ◽  
Guannan Su ◽  
...  
Keyword(s):  
Diagnostic Criteria ◽  
Clinical Symptoms ◽  
Southern China ◽  
High Sensitivity ◽  
Northern China ◽  
Chinese Patients ◽  
Tertiary Referral Centre ◽  
Tree Algorithms ◽  
Vitreous Opacities ◽  
Fuchs Uveitis Syndrome

Background/aimsFuchs’ uveitis syndrome (FUS) is one of the frequently misdiagnosed uveitis entities, which is partly due to the absence of internationally recognised diagnostic criteria. This study was performed to develop and evaluate a set of revised diagnostic criteria for FUS.MethodsThe clinical data of Chinese patients with FUS and patients with non-FUS were collected and analysed from a tertiary referral centre between April 2008 and December 2020. A total of 593 patients with FUS and 625 patients with non-FUS from northern China were enrolled for the development of diagnostic criteria for FUS. Three hundred and seventy-seven patients with FUS and 503 patients with non-FUS from southern China were used to validate the criteria. Clinical symptoms and ocular signs were collected from all patients with FUS and patients with non-FUS. Multivariate two-step cluster analysis, logistic regression and decision tree algorithms in combination with the clinical judgement of uveitis experts were used to revise diagnostic criteria for FUS.ResultsThree essential findings including diffuse iris depigmentation, absence of posterior synechiae, mild inflammation in the anterior chamber at presentation and five associated findings including mostly unilateral involvement, cataract, vitreous opacities, absence of acute symptoms and characteristic iris nodules were used in the development of FUS diagnostic criteria. All essential findings were required for the diagnosis of FUS, and the diagnosis was further strengthened by the presence of associated findings.ConclusionRevised diagnostic criteria for FUS were developed and validated by analysing data from Chinese patients and showed a high sensitivity (96.55%) and specificity (97.42%).

Coronary Care in a General Hospital

1971 ◽  
Vol 16 (3) ◽  
pp. 173-182 ◽  
Author(s):  
Gavin Shaw ◽  
Bernard Groden ◽  
Evelyn Hastings
Keyword(s):  
Myocardial Infarction ◽  
Intensive Care Unit ◽  
Intensive Care ◽  
General Hospital ◽  
First Year ◽  
Duration Of Stay ◽  
Before And After ◽  
The Mean ◽  
Coronary Care ◽  
Made In

The establishment, staffing and structure and observations made in the first year of the existence of coronary care in an intensive care unit in a general hospital are recorded. Two hundred and twenty eight patients were admitted during the year in whom the diagnosis of myocardial infarction was confirmed. There were 29 deaths in the unit and 14 deaths occurred in the wards of the hospital after discharge from the unit. 49.1 per cent of the patients were admitted within 4 hours of the onset of symptoms and the mean duration of stay in the unit was 86.5 hours. The type of arrhythmia detected in the unit, and the treatment given to the patients both before and after admission to the intensive care unit are described.

scholarly journals Five-year changes in anterior segment parameters in an older population in urban southern China: the Liwan Eye Study

2019 ◽  
Vol 104 (4) ◽  
pp. 582-587 ◽  
Author(s):  
Yu Jiang ◽  
Decai Wang ◽  
Wei Wang ◽  
Feng Chen ◽  
Lanhua Wang ◽  
...  
Keyword(s):  
Anterior Chamber ◽  
Pupil Diameter ◽  
Southern China ◽  
Anterior Segment ◽  
Population Based ◽  
Light Conditions ◽  
Anterior Chamber Angle ◽  
The Mean ◽  
Angle Width

PurposeTo investigate the 5-year changes in static and dynamic anterior segment optical coherence tomography (AS-OCT) parameters and their predictors.MethodsThis was a prospective, population-based cohort study of people aged 50 years and older residing in the Liwan District, Guangzhou, China. Standardised AS-OCT scans were performed in November 2008 and November 2013 under dark and light conditions. Customised software was used to analyse horizontal AS-OCT images. Parameters in dark and measurements of light-to-dark changes were used for analyses.ResultsA total of 186 (71.8%) subjects underwent AS-OCT twice, 5 years apart and were included for analyses. The mean age in 2008 was 64.7±7.0 years, and 60.2% were women. The anterior chamber width (ACW) decreased from 11.74±0.44 mm in 2008 to 11.60±0.37 mm in 2013 (p=0.001). There was a trend towards a decrease in dynamic capacity (light-to-dark changes) in the anterior segment, with decreased iris thickness at 750 µm (ΔIT750), ΔACW, Δ anterior chamber area (ACA) and Δ pupil diameter at 5 years (all p<0.05). After adjusting for age and sex, the following baseline parameters were associated with a greater decrease rate in trabecular iris space area at 500 µm (TISA500) at 5 years: TISA500, IT750 and ACA in dark (p<0.001 for all).ConclusionsAnterior chamber angle width decreased and the amount of light-to-dark changes declined during 5-year follow-up. Subjects with greater height, wider angle width and thicker iris at baseline have greater angle narrowing at follow-up.

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