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1ANNUAL DISTRIBUTION FEATURES OF PRECIPITATION IN CHINA AND THEIR INTERANNUAL VARIATIONS显示文摘The hierarchy and definition of the precipitation-concentration degree and precipitation-concentration period of annual precipitation have been proposed by using the so-called vectormethod of annual distribution of precipitation,so that the two relevant parameters can representthe annual distribution of total precipitation correctly and indeed accurately.The relationshipbetween the spatial and temporal distribution patterns and variations of the two parameters and theannual precipitation amount in China has been further investigated.Results demonstrate that theprecipitation-concentration degree and the precipitation-concentration period increase fromsoutheast to northwest gradually.Moreover there obviously exists a belt pattern:the largestvariability of the precipitation-concentration degree and the precipitation-concentration periodoccurs in the Yellow River Valley and the middle and lower reaches of the Yangtze River,corresponding to the significant zones in which flood and drought take place frequently.It is foundthat there exist high correlations between the precipitation-concentration degree and precipitation-concentration period and the annual precipitation amount in Northeast China,North China,themiddle and lower reaches of the Yangtze River.Furthermore,8-year and 22-year periodic oscillations in the precipitation-concentration degreeand 6-year and 12-year cycles in the precipitation-concentration period are identified by use of theirMorlet wavelet analysis.张录军 钱永甫 2003Acta meteorologica Sinica2003,17,2:112
2Cancer incidence,mortality,and burden in China:a time-trend analysis and comparison with the United States and United Kingdom based on the global epidemiological data released in 2020显示文摘Background:Cancer is one of the leading causes of death and a main economic burden in China.Investigating the differences in cancer patterns and control strategies between China and developed countries could provide reference for policy planning and contribute to improving cancer control measures.In this study,we reviewed the rates and trends of cancer incidence and mortality and disability-adjusted life year(DALY)burden in China,and compared them with those in the United States(US)and the United Kingdom(UK).Methods:Cancer incidence,mortality,and DALY data for China,US and UK were obtained fromtheGLOBOCAN2020 online database,Global Burden of Disease(GBD)2019 study,and Cancer Incidence in Five Continents plus database(CI5 plus).Trends of cancer incidence and mortality in China,US,and UK were analyzed using Joinpoint regression models to calculate annual percent changes(APCs)and identify the best-fitting joinpoints.Results:An estimated 4,568,754 newly diagnosed cancer cases and 3,002,899 cancer deaths occurred in China in 2020.Additionally,cancers resulted in 67,340,309 DALYs in China.Compared to the US and UK,China had lower cancer incidence but higher cancer mortality andDALY rates.Furthermore,the cancer spectrum of China was changing,with a rapid increase incidence and burden of lung,breast,colorectal,and prostate cancer in addition to a high incidence and heavy burden of liver,stomach,esophageal,and cervical cancer.Conclusions:The cancer spectrum of China is changing from a developing country to a developed country.Population aging and increase of unhealthy lifestyles would continue to increase the cancer burden of China.Therefore,the Chinese authorities should adjust the national cancer control program with reference to the practices of cancer control which have been well-established in the developed countries,and taking consideration of the diversity of cancer types by of different regions in China at the same time.Haibo Qiu Sumei Cao Ruihua Xu 2021Cancer Communications2021,41,10:194
3Epidemiology of pancreatic cancer显示文摘Cancer of the pancreas remains one of the deadliest cancer types. Based on the GLOBOCAN 2012 estimates, pancreatic cancer causes more than 331000 deaths per year, ranking as the seventh leading cause of cancer death in both sexes together. Globally, about 338000 people had pancreatic cancer in 2012, making it the 11^(th) most common cancer. The highest incidence and mortality rates of pancreatic cancer are found in developed countries. Trends for pancreatic cancer incidence and mortality varied considerably in the world. A known cause of pancreatic cancer is tobacco smoking. This risk factor is likely to explain some of the international variations and gender differences. The overall five-year survival rate is about 6%(ranges from 2% to 9%), but this vary very small between developed and developing countries. To date, the causes of pancreatic cancer are still insufficiently known, although certain risk factors have been identified, such as smoking, obesity, genetics, diabetes, diet, inactivity. There are no current screening recommendations for pancreatic cancer, so primary prevention is of utmost importance. A better understanding of the etiology and identifying the risk factors is essential for the primary prevention of this disease.Milena Ilic Irena Ilic 2016World Journal of Gastroenterology2016,22,44:95
4A review of selective laser melting of aluminum alloys: Processing,microstructure, property and developing trends显示文摘Selective laser melting(SLM) is an attractive rapid prototyping technology for the fabrication of metallic components with complex structure and high performance. Aluminum alloy, one of the most pervasive structural materials, is well known for high specific strength and good corrosion resistance. But the poor laser formability of aluminum alloy restricts its application. There are problems such as limited processable materials, immature process conditions and metallurgical defects on SLM processing aluminum alloys. Some efforts have been made to solve the above problems. This paper discusses the current research status both related to the scientific understanding and technology applications. The paper begins with a brief introduction of basic concepts of aluminum alloys and technology characterization of laser selective melting. In addition, solidification theory of SLM process and formation mechanism of metallurgical defects are discussed. Then, the current research status of microstructure, properties and heat treatment of SLM processing aluminum alloys is systematically reviewed respectively. Lastly, a future outlook is given at the end of this review paper.Jinliang Zhang Bo Song Qingsong Wei Dave Bourell Yusheng Shi 2019Journal of Materials Science & Technology2019,35,2:77
5Cancer burden and trends in China:A review and comparison with Japan and South Korea显示文摘Objective:To summarize the cancer burden and trends in China,compare the differences among China,Japan,and South Korea and discuss possible causes of the disparities.Methods:Incidence and mortality data were extracted from the online cancer database including the GLOBOCAN 2018 and the Global Burden of Disease Study 2017.Trend analysis was conducted using the joinpoint analysis,and annual percent changes were calculated.Results:Cancers resulted in approximately 62.9 million disability-adjusted life years(DALYs)in China in 2017.Lung cancer had the greatest contribution,followed by liver cancer,stomach cancer,and esophageal cancer.The trajectory of progress in the reduction of liver and stomach cancers was observed in China.However,China still faced a heavy burden of lung cancer and a growing burden of cancers related to westernized lifestyle such as colorectal cancer,while Japan and South Korea have achieved reductions in colorectal cancer and lung cancer,respectively.Besides,China had a lower age-standardized cancer incidence rate but higher cancer mortality and DALY rates than Japan and South Korea.Conclusions:China is in the cancer transition stage with a rising burden of colorectal,prostate,and breast cancers along with a heavy burden of lung and upper digestive tract cancers.Taking into consideration the effectiveness of screening and tobacco control in Japan and South Korea,improvement in the current tobacco control policy and cancer screening systems may contribute to cancer control in China.Dianqin Sun Maomao Cao He Li Siyi He Wanqing Chen 2020Chinese Journal of Cancer Research2020,32,2:71
6Trends of the precipitation acidity over China during 1992–2006显示文摘The trends of the precipitation acidity from 1992 to 2006 were studied, based on the long-term acid rain observations at 74 sites in China. The results show that there was no remarkable change or extension of acid rain area (i.e., with annual mean of precipitation pH<5.6) during the 15 years. The largest and continuous acid rain area exists in the south of the Yangtze River, while the acid rain areas north of the Yangtze River remain separate. The severe acid rain area (i.e., with annual mean of precipitation pH<4.5) exists mainly in the south of the Yangtze River. The overall precipitation acidity for the 74 stations showed different trends before 1999 and after 2000. In the period 1992–1999, the precipitation acidity at most of the sites remained steady or showed a decreasing trend. After 2000, however, an increasing trend of the precipitation acidity was observed at many sites in North China, Central China, East China, and South China. As a result, the pattern of acid rain area changed during 1992–2006. The precipitation over North China, Central China, and South China became more acidified in the 15 years, with more pronounced trends in North China and the north of Central China. A slight decrease in the precipitation acidity was found in Southwest China, an area characterized as severest acid rain area for about two decades after the early 1980s. Consequently, the center of severe acid rain area in the south of the Yangtze River moved eastwards. The non-hydrogen conductivity (NHC), which is defined as the difference between the measured precipitation conductivity and the H+ conductivity calculated from measured pH, was estimated and treated as a proxy of soluble ions in precipitation. The result shows that the overall trend of the NHC before 1999 was pronounced and positive, while the trend after 2000 was inconspicuous or slightly negative. During 2000–2006, the change rate of pH was positively correlated to that of the NHC at 21 sites, implying that the increasing acidities found at these sites may partly be attributed to the decrease in the concentration of airborne particulate matter in recent years.TANG Jie XU XiaoBin BA Jin WANG ShuFeng 2010Chinese Science Bulletin2010,55,17:22
7Trends in cancer mortality in China from 2004 to 2018:A nationwide longitudinal study显示文摘Background:The long-term trend in cancer death in a rapidly developing country provides information for cancer prophylaxis.Here,we aimed to identify the trends in cancer mortality in China during the 2004-2018 period.Methods:Using raw data from the national mortality surveillance system of China,we assessed the mortalities of all cancer and site-specific cancers during the 2004-2018 period.The participants were divided into three age groups:≥65 years,40-64 years,and≤39 years.Changing trends in cancer death by gender,residency,and tumor location were estimated using fitting joinpoint models to log-transformed crude mortality rates(CMRs)and age-standardizedmortality rates(ASMRs).Results:Cancer death accounted for 24% of all-cause of death in China during 2014-2018.The CMR of all cancer was 150.0 per 100,000 persons.Cancer was the leading cause of death in the population<65 years.The six major cancer types(lung/bronchus cancer,liver cancer,stomach cancer,esophagus cancer,colorectal cancer,and pancreas cancer)accounted for 75.85% of all cancer deaths.The CMR of all cancer increased while the ASMR decreased during 2014-2018(P<0.001).Lung/bronchus cancer and liver cancer were the leading causes of cancer death in the population<65 years,accounting for 45.31%(CMR)and 44.35%(ASMR)of all cancer death,respectively.The ASMR of liver cancer was higher in the 40-64 years population than in the≥65 years population,in contrast to the other five major cancers.The ASMRs of liver cancer,stomach cancer,and esophagus cancer decreased although they were higher in rural residents than in urban residents;the ASMRs of lung/bronchus cancer,colorectal cancer,and pancreas cancer increased in rural residents although they were higher in urban residents than in rural residents during 2014-2018.Conclusion:Although the ASMR of all cancer decreased in China during 2004-2018,lung/bronchus cancer and liver cancer remained the leading causes of cancer-related premature death.Lung/bronchus cancer,colorectal cancer,and pancreas cancer increased in rural residents.Dongming Jiang Lijuan Zhang Wenbin Liu Yibo Ding Jianhua Yin Rongbing Ren Qi Li Yifan Chen Jiaying Shen Xiaojie Tan Hongwei Zhang Guangwen Cao 2021Cancer Communications2021,41,10:23
8Pancreatic cancer:A review of epidemiology,trend,and risk factors显示文摘Despite rapid advances in modern medical technology and significant improvements in survival rates of many cancers,pancreatic cancer is still a highly lethal gastrointestinal cancer with a low 5-year survival rate and difficulty in early detection.At present,the incidence and mortality of pancreatic cancer are increasing year by year worldwide,no matter in the United States,Europe,Japan,or China.Globally,the incidence of pancreatic cancer is projected to increase to 18.6 per 100000 in 2050,with the average annual growth of 1.1%,meaning that pancreatic cancer will pose a significant public health burden.Due to the special anatomical location of the pancreas,the development of pancreatic cancer is usually diagnosed at a late stage with obvious clinical symptoms.Therefore,a comprehensive understanding of the risk factors for pancreatic cancer is of great clinical significance for effective prevention of pancreatic cancer.In this paper,the epidemiological characteristics,developmental trends,and risk factors of pancreatic cancer are reviewed and analyzed in detail.Jian-Xiong Hu Cheng-Fei Zhao Wen-Biao Chen Qi-Cai Liu Qu-Wen Li Yan-Ya Lin Feng Gao 2021World Journal of Gastroenterology2021,27,27:20
9Asymmetric variability between maximum and minimum temperatures in Northeastern Tibetan Plateau:Evidence from tree rings显示文摘Ecological systems in the headwaters of the Yellow River, characterized by hash natural environmental conditions, are very vulnerable to climatic change. In the most recent decades, this area greatly attracted the public's attention for its more and more deteriorating environmental conditions. Based on tree-ring samples from the Xiqing Mountain and A'nyêmagên Mountains at the headwaters of the Yellow River in the Northeastern Tibetan Plateau, we reconstructed the minimum temperatures in the winter half year over the last 425 years and the maximum temperatures in the summer half year over the past 700 years in this region. The variation of minimum temperature in the winter half year during the time span of 1578―1940 was a relatively stable trend, which was followed by an abrupt warming trend since 1941. However, there is no significant warming trend for the maximum temperature in the summer half year over the 20th century. The asymmetric variation patterns between the minimum and maximum temperatures were observed in this study over the past 425 years. During the past 425 years, there are similar variation patterns between the minimum and maximum temperatures; however, the minimum temperatures vary about 25 years earlier compared to the maximum temperatures. If such a trend of variation patterns between the minimum and maximum temperatures over the past 425 years continues in the future 30 years, the maximum temperature in this region will increase significantly.Jacoby GORDON 2008Science China Earth Sciences2008,51,1:19
10Trend analysis of sediment grain size and sedimentary process in the central South Yellow Sea显示文摘With the method of trend analysis of sediment grain size, the sediment transport trend of the fine-grained sediments area in the central South Yellow Sea was studied. The results demonstrated that there is a sedimentation center around the point of 123.4° E, 35.1°N, and the sediments outside the center are transported to it. The patterns of sediment transportation and deposition in the Yellow Sea should be controlled by cyclonic circulation (including the Yellow Sea Cold Water Mass) and cold water gyre. The study also showed that the method of trend analysis of sediment grain size has prospective utilization in the fine-grained sediment deposited area on large-scale continental shelf.SHI Xuefa CHEN Chunfeng LIU Yanguang REN Hong WANG Huiyan 2002Chinese Science Bulletin2002,47,14:17
11Global aridification in the second half of the 20th century and its relationship to large-scale climate background显示文摘The variation in surface wetness index (SWI), which was derived from global gridded monthly precipi- tation and monthly mean surface air temperature datasets of Climatic Research Unit (CRU), from 1951― 2002 over global land was analyzed in this paper. The characteristics of the SWI variation in global continents, such as North America, South America, Eurasia, Africa, and Australia, were compared. In addition, the correlation between the SWI variation of each continent (or across the globe) and the large-scale background closely related to SST variations, which affects climate change, was analyzed. The results indicate that the SWI variation shows distinct regional characteristics in the second half of the 20th century under global warming. A drying trend in the last 52 years occurred in Africa, Eurasia, Australia and South America, most obviously in Africa and Eurasia. North America shows a wetting trend after 1976. A 30-year period of dry-wet oscillation is found in South America and Australia; the latest is in a drying period in two regions. The results also revealed that global warming has changed the dry-wet pattern of the global land. South America and Australia have a drying trend despite in- creases in precipitation. This indicates that increases in surface air temperature cannot be ignored in aridification studies. Global dry-wet variation is closely related to large-scale SST variations: the drying trend in Africa and Eurasia and the wetting trend in North America are correlated with Pacific Decadal Oscillation (PDO); the interdecadal oscillation of SWI in South America and Australia is consistent with the interdecadal variation in Southern Oscillation Index (SOI).MA ZhuGuo FU CongBin 2007Science China Earth Sciences2007,50,5:17
12The mortality of lung cancer attributable to smoking among adults in China and the United States during 1990–2017显示文摘Background:Statistical data on the burden and relevant risk factors of lung cancer are valuable for policy-making.This study aimed to compare the mortality of lung cancer attributable to smoking stratified by sex and age among adults in China and the United States(US).Methods:We extracted age-standardized mortality rates of lung cancer during 1990-2017 using the comparative risk assessment framework of the 2017 Global Burden of Disease study.We performed an age-period-cohort analysis to estimate time trend of lung cancer mortality attributable to smoking.Results:During 1990-2017,the age-standardized mortality rate of lung cancer was increasing in China but decreasing in the US for both sexes.The mortality attributable to smoking in China showed a generally increasing trend,while a continuous decrease was observed in the US.The age-period-cohort analysis showed a similar trend of age effect among adults between China and the US:the mortality substantially increased from the 30-34 to 80-84 age group and subsequently decreased in the 90-94 age group.However,the period effect rapidly increased in Chinese adults during 1990-2017,while it tended to be stable in the US although it was still slightly increasing in women.The cohort effect generally peaked in the earlier cohort born in 1902-1906 in the two countries.Conclusions:During 1990-2017,the lung cancer mortality attributable to smoking and the period effect are generally increasing in Chinese adults;the mortality attributable to smoking is decreasing in the US adults,but the period effect tends to be stable.The rapid aging and prevalence of smoking may intensify the increasing mortality of lung cancer in China.Xiaoxue Liu Yong Yu Minsheng Wang Sumaira Mubarik Fang Wang Yafeng Wang Runtang Meng Chuanhua Yu 2020Cancer Communications2020,40,11:17
13Trends and risk factors of lung cancer in China显示文摘China is faced with heavy burdens caused by lung cancer,which has climbed to the top of both cancer incidence and mortality spectrums.The age-standardized rates of incidence and mortality have shown a trend of gradual uptrends in the last decades,while the crude rates rise much quickly due to the aging of population.Although the improvement in health care has contributed to better survival of lung cancer,its prognosis is still challenging.Apart from the common risk factors such as tobacco use,air pollution,and occupational hazards,some specific factors like Chinese-style cooking also have posed great threats to human health.In light of such national conditions,specific interventions should be conducted to curb the burden of lung cancer including smoking cessation,improvement of air quality,early detection and effective treatment of lung cancer.Siyi He He Li Maomao Cao Dianqin Sun Lin Lei Ni Li Ji Peng Wanqing Chen 2020Chinese Journal of Cancer Research2020,32,6:16
14Colorectal cancer burden and trends:Comparison between China and major burden countries in the world显示文摘Objective:To summarize the colorectal cancer(CRC)burden and trend in the world,and compare the difference of CRC burden between other countries and China.Methods:Incidence and mortality data were extracted from the GLOBOCAN2018 and Cancer Incidence in Five Continents.Age-specific incidence trend was conducted by Joinpoint analysis and average annual percent changes were calculated.Results:About 1.85 million new cases and 0.88 million deaths were expected in 2018 worldwide,including 0.52 million(28.20%)new cases and 0.25 million(28.11%)deaths in China.Hungary had the highest age-standardized incidence and mortality rates in the world,while for China,the incidence and mortality rates were only half of that.CRC incidence and mortality were highly correlated with human development index(HDI).Unlike the rapid increase in Republic of Korea and the downward trend in Canada and Australia,the age-standardized incidence rates by world standard population in China and Norway were rising gradually.The age-specific incidence rate in the age group of 50-59 years in China was increasing rapidly,while in Republic of Korea and Canada,the fastest growing age group was 30-39 years.Conclusions:The variations of CRC burden reflect the difference of risk factors,as well as levels of HDI and screening(early detection activities).The burden of CRC in China is high,and the incidence of CRC continues to increase,which may lead to a sustained increase in the burden of CRC in China in the future.Screening should be expanded to control CRC,and focused on young people in China.Jiachen Zhou Rongshou Zheng Siwei Zhang Hongmei Zeng Shaoming Wang Ru Chen Kexin Sun Minjuan Li Jianhua Gu Guihua Zhuang Wenqiang Wei 2021Chinese Journal of Cancer Research2021,33,1:16
15Colorectal cancer incidence and mortality:the current status,temporal trends and their attributable risk factors in 60 countries in 2000–2019显示文摘Background:Globally,colorectal cancer(CRC)imposes a substantial burden on healthcare systems and confers considerable medical expenditures.We aimed to evaluate the global and regional burden in epidemiological trends and factors associated with the incidence and mortality of CRC.Methods:We used data from the GLOBOCAN database to estimate CRC incidence and mortality worldwide in 2020 and their association with the human development index(HDI).Trends of age-standardized rates of incidence and mortality in 60 countries(2000–2019)were evaluated by Joinpoint regression analysis using data of Global Burden of Disease 2019.The association between exposure to country-level lifestyle,metabolic and socioeconomic factors obtained from the World Health Organization Global Health Observatory and World Bank DataBank data and CRC incidence and mortality was determined by multivariable linear regression.Results:CRC incidence and mortality varied greatly in the 60 selected countries,and much higher incidence and mortality were observed in countries with higher HDIs,and vice versa.From 2000 to 2019,significant increases of incidence and mortality were observed for 33 countries(average annual percent changes[AAPCs],0.24–3.82)and 18 countries(AAPCs,0.41–2.22),respectively.A stronger increase in incidence was observed among males(AAPCs,0.36–4.54)and individuals<50 years(AAPCs,0.56–3.86).Notably,15 countries showed significant decreases in both incidence(AAPCs,0.24 to2.19)and mortality(AAPCs,0.84 to2.74).A significant increase of incidence among individuals<50 years was observed in 30 countries(AAPCs,0.28–3.62).Countries with higher incidence were more likely to have a higher prevalence of alcohol drinking,higher level of cholesterol level,higher level of unemployment,and a poorer healthcare system.Conclusions:Some high-HDI countries showed decreasing trends in CRC incidence and mortality,whereas developing countries that previously had low disease burden showed significantly increased incidence and mortality trends,especially in males and populations≥50 years,which require targeted preventive health programs.Bin Lu Na Li Chen-Yu Luo Jie Cai Ming Lu Yu-Han Zhang Hong-Da Chen Min Dai 2021Chinese Medical Journal2021,,16:13
16Trends of sea level rise in the South China Sea during the 1990s: An altimetry result显示文摘Using 7 years of TOPEX/POSEIDON satellite altimetry data, we have identified a general trend of sea level rising in the South China Sea between January 1993 and December 1999. The estimated bulk rising rate of the entire basin is-1 cm/a. The rise of sea level appears to be spatially non-homogeneous, which shows a highest rate of 2.7 cm/a in the deep basin west of Luzon and generally low (even negative) rates over the shallow continental shelves. It is believed that the observed rapid rising of sea level is a regional phenomenon and is mainly caused by warming of the upper layer of the South China Sea, which showed a bulk warming rate of 0.15癈/a in the same period. It is also suggested that the observed rising trend is mainly a decadal signal, which is possibly associated with decadal variation of the Pacific warm pool region.Li Li Xu Jindian Cai Rongshuo 2002Chinese Science Bulletin2002,47,7:12
17Study on Ann-Based Multi-Step Prediction Model of Short-Term Climatic Variation显示文摘In the context of 1905-1995 series from Nanjing and Hangzhou, study is undertaken of establishing a predictive model of annual mean temperature in 1996-2005 to come over the Changjiang (Yangtze River) delta region through mean generating function and artificial neural network in combination. Results show that the established model yields mean error of 0.45℃ for their absolute values of annual mean temperature from 10 yearly independent samples (1986-1995) and the difference between the mean predictions and related measurements is 0. 156℃, The developed model is found superior to a mean generating function regression model both in historical data fitting and independent sample prediction.金龙 居为民 缪启龙 2000Advances in Atmospheric Sciences2000,17,1:11
18基于Hurst指数的1982–2013年蒙古高原植被动态变化趋势及其影响因素分析(英文)显示文摘This study analyzed the spatial and temporal variations in the Normalized Difference Vegetation Index(NDVI) on the Mongolian Plateau from 1982–2013 using Global Inventory Modeling and Mapping Studies(GIMMS) NDVI3 g data and explored the effects of climate factors and human activities on vegetation. The results indicate that NDVI has slight upward trend in the Mongolian Plateau over the last 32 years. The area in which NDVI increased was much larger than that in which it decreased. Increased NDVI was primarily distributed in the southern part of the plateau, especially in the agro-pastoral ecotone of Inner Mongolia. Improvement in the vegetative cover is predicted for a larger area compared to that in which degradation is predicted based on Hurst exponent analysis. The NDVI-indicated vegetation growth in the Mongolian Plateau is a combined result of climate variations and human activities. Specifically, the precipitation has been the dominant factor and the recent human effort in protecting the ecological environments has left readily detectable imprints in the NDVI data series.佟斯琴 张继权 包玉海 来全 连晓 丽娜 包勇斌 2018Journal of Geographical Sciences2018,28,5:11
19城市化与极端降水显示文摘With rapid urbanization occurring across developing countries since the late last century,many recent observational studies show statistically significant increases in the intensity and frequency of short-duration(i.e.,less than 6 h)urban extreme rainfall(UER)events over and downwind of major megacities during the warm season,but decreasing trends in light rainfall and rainy day over surrounding areas and also in total regional rainfall[1–4](An UER event is typically defined as a rainfall rate of greater than 95th percentile or higher over an urban region of concern).Moreover,the number of short-duration UER events tends to increase faster than that of long-duration ones,and the increasing UER trend appears to be more pronounced over some of China’s major megacities due to more rapid urbanization during the past three decades[1–3].As an example,a near-century climatology of hourly UER rates at a downwind maximum-accumulated rainfall station from the megacity of Shanghai is given in Fig.1[1],showing an increasing hourly rainfall trend since the rapid urbanization beginning from 1981 that is much greater than a longer-term hourly rainfall trend(Fig.1a).The large increases in the megacity-averaged hourly rainfall trend during Shanghai’s rapid urbanization period are also evident(Fig.1b).张大林 2020Science Bulletin2020,65,7:9
20Re-Assessing Climatic Warming in China since 1900显示文摘The regional mean surface air temperature(SAT)in China has risen with a rate of 1.3–1.7℃(100 yr)^-1 since 1900,based on the recently developed homogenized observations.This estimate is larger than those[0.5–0.8℃(100 yr)^-1]adopted in the early National Reports of Climate Change in China.The present paper reviews the studies of the longterm SAT series of China,highlighting the homogenization of station observations as the key progress.The SAT series of China in early studies showed a prominent warm peak in the 1940s,mainly due to inhomogeneous records associated with site-moves of a number of stations from urban to outskirts in the early 1950s,thus leading to underestimates of the centennial warming trend.Parts of China were relatively warm around the 1940s but with differentphase interdecadal variations,while some parts were even relatively cool.This fact is supported by proxy data and could partly be explained by interdecadal changes in large-scale circulation.The effect of urbanization should have a minor contribution to the observed warming in China,although the estimates of such contributions for individual urban stations remain controversial.Further studies relevant to the present topic are discussed.Zhongwei YAN Yihui DING Panmao ZHAI Lianchun SONG Lijuan CAO Zhen LI 2020Journal of Meteorological Research2020,34,2:9
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