基于TerraClimate数据集的1960—2019年中国干湿气候变化特征

考虑地理地形和下垫面等因素的影响,选用高空间分辨率TerraClimate数据集分析中国干湿气候变化特征具有重要意义。以该数据集1960—2019年的降水和蒸散月度数据为基础,基于降水量和湿润指数对中国各干湿区范围、干湿气候界线以气候变化趋势进行了分析。结果表明:前后30 a相比,基于两种指标划分的干旱区和湿润区面积负增长,半干旱区和半湿润区面积正增长;各区分界线主要在黑龙江、内蒙古中部和东北部、淮河以及黑龙江等地按年代波动;近60 a来,我国的降水量和湿润指数变化趋势不显著,均在西部和东南部趋于增大,气候变湿,在中部和东北部趋于减小,气候变干。与利用气象站点观测资料的研究结果进行对比评价,TerraClimate数据集能够很好反映中国区域的干湿状况及其变化特征,且降水数据的适用性更为突出。

An Overview of Dry-wet Climate Variability among Monsoon-Westerly Regions and the Monsoon Northernmost Marginal Active Zone in China

Climate in China's Mainland can be divided into the monsoon region in the southeast and the westerly region in the northwest as well as the intercross zone, i.e., the monsoon northernmost marginal active zone that is oriented from Southwest China to the upper Yellow River, North China, and Northeast China. In the three regions, dry-wet climate changes are directly linked to the interaction of the southerly monsoon flow on the east side of the Tibetan Plateau and the westerly flow on the north side of the Plateau from the inter-annual to inter-decadal timescales. Some basic features of climate variability in the three regions for the last half century and the historical hundreds of years are reviewed in this paper. In the last half century, an increasing trend of summer precipitation associated with the enhancing westerly flow is found in the westerly region from Xinjiang to northern parts of North China and Northeast China. On the other hand, an increasing trend of summer precipitation along the Yangtze River and a decreasing trend of summer precipitation along the monsoon northernmost marginal active zone are associated with the weakening monsoon flow in East Asia. Historical documents are widely distributed in the monsoon region for hundreds of years and natural climate proxies are constructed in the non-monsoon region, while two types of climate proxies can be commonly found over the monsoon northernmost marginal active zone. In the monsoon region, dry-wet variation centers are altered among North China, the lower Yangtze River, and South China from one century to another. Dry or wet anomalies are firstly observed along the monsoon northernmost marginal active zone and shifted southward or southeastward to the Yangtze River valley and South China in about a 70-year timescale. Severe drought events are experienced along the monsoon northernmost marginal active zone during the last 5 centuries. Inter-decadal dry-wet variations are depicted by natural proxies for the last 4-5 centuries in several areas over the non-monsoon region. Some questions, such as the impact of global warming on dry-wet regime changes in China, complex interactions between the monsoon and westerly flows in Northeast China, and the integrated multi-proxy analysis throughout all of China, are proposed.

The Effects of Climate Change on the Planting Boundary and Potential Yield for Different Rice Cropping Systems in Southern China

Based on climate data from 254 meteorological stations, this study estimated the effects of climate change on rice planting boundaries and potential yields in the southern China during 1951-2010. The results indicated a signiifcant northward shift and westward expansion of northern boundaries for rice planting in the southern China. Compared with the period of 1951-1980, the average temperature during rice growing season in the period of 1981-2010 increased by 0.4＆#176;C, and the northern planting boundaries for single rice cropping system （SRCS）, early triple cropping rice system （ETCRS）, medium triple cropping rice system （MTCRS）, and late triple cropping rice system （LTCRS） moved northward by 10, 30, 52 and 66 km, respectively. In addition, compared with the period of 1951-1980, the suitable planting area for SRCS was reduced by 11%during the period of 1981-2010. However, the suitable planting areas for other rice cropping systems increased, with the increasing amplitude of 3, 8, and 10%for ETCRS, MTCRS and LTCRS, respectively. In general, the light and temperature potential productivity of rice decreased by 2.5%. Without considering the change of rice cultivars, the northern planting boundaries for different rice cropping systems showed a northward shift tendency. Climate change resulted in decrease of per unit area yield for SRCS and the annual average yields of ETCRS and LTCRS. Nevertheless, the overall rice production in the entire research area showed a decreasing trend even with the increasing trend of annual average yield for MTCRS.

Interdecadal fluctuation of dry and wet climate boundaries in China in the past 50 years

Based on the mean yearly precipitation and the total yearly evaporation data of 295 meteorological stations in China in 1951-1999, the aridity index is calculated in this paper. According to the aridity index, the climatic regions in China are classified into three types, namely, arid region, semi-arid region and humid region. Dry and wet climate boundaries in China fluctuate markedly and differentiate greatly in each region in the past 50 years. The fluctuation amplitudes are 20-400 km in Northeast China, 40-400 km in North China, 30-350 km in the eastern part of Northwest China and 40-370 km in Southwest China. Before the 1980s (including 1980), the climate tended to be dry in Northeast China and North China, to be wet in the eastern part of Northwest China and very wet in Southwest China. Since the 1990s there have been dry signs in Southwest China, the eastern part of Northwest China and North China. The climate becomes wetter in Northeast China. Semi-arid region is the transitional zone between humid and arid regions, the monsoon edge belt in China, and the susceptible region of environmental evolution. At the end of the 1960s dry and wet climate in China witnessed abrupt changes, changing wetness into dryness. Dry and wet climate boundaries show the fluctuation characteristics of the whole shifts and the opposite fluctuations of eastward, westward, southward and northward directions. The fluctuations of climatic boundaries and the dry and wet variations of climate have distinctive interdecadal features.

Changes of Dry-wet Climate in the Dry Season in Yunnan(1961-2007)

Factor analysis was used to investigate the changes of dry-wet climate in the dry season in Yunnan during 1961-2007 based on observed data from 15 stations.Three common factors were extracted from the 9 climatic factors.The results showed that the dry-wet climate has evidently changed since the early 1960s.The general trends in the changes of drywet climate were described as slight decrease in humidity and gradual enhancement in drought intensity.The climate during 1960s-1980s was under weak-medium drought.But since early 1990s,dry conditions have markedly strengthened and continued due to uneven temporal distribution of rainfall and climate warming.

Influence of the Boundary Forcing on the Internal Variability of a Regional Climate Model

The internal variability of a ten-member ensemble of the regional climate model REMO over Europe is investigated. It is shown that the annual cycle of internal variability behaves differently compared to earlier studies that focused on other regions. To gain better insight into the dependence of the internal variability on the boundary forcing variability, a circulation type classification is performed on the forcing data. It can be shown that especially in the winter season internal variability is dependent on the circulation type included in the boundary forcing, whereas in the summer season the level and pattern of internal variability is rather independent from the circulation type of the driving field. It is concluded that for Europe the internal variability of REMO in winter is governed by circulation patterns related to the North-Atlantic Oscillation, whereas in summer local processes play a bigger role.

Climate and meteorological processes of the East Antarctic ice sheet between Zhongshan and Dome-A

The 1228 km over-snow traverse route between the Chinese Zhongshan Station, on the coast of Prydz Bay, and Dome-A, at 4091 m elevation the highest point of the East Antarctic ice sheet, has been the focus of CHINARE surface meteorological and climate studies since 2002. A network of seven Automatic Weather Stations has been deployed along this section, including at Dome-A itself, and some of these have now provided nearly-hourly data for over a decade. Atmospheric boundary layer turbulence and radiation observations have been made over the near-coastal ice sheet inland of Zhongshan and surface turbulence measurements using an ultrasonic anemometer system have also been made in the deep interior of the ice sheet. Summer GPS radiosonde soundings of the atmospheric boundary layer have been made at Kunlun Station, near Dome-A. In this paper these observations are combined to provide a comprehensive overview of the meteorological regime of this region of the ice sheet, its climate variability, and as a reference for future study of climate change. This includes investigation of the variation of surface climate features with elevation and distance from the coast, the height and structure of the boundary layer over the ice sheet, and seasonal and regional changes in ice/snow-air interactions, including turbulent and radiative energy fluxes. The air temperature and snow temperature between the coastal Zhongshan and Dome-A on the inland plateau have not changed significantly in the past decade compared with the inter-annual variability.

国家气候观象台多维度观测能力建设及科学研究——以深圳为例

国家气候观象台是中国国家级气象观测的重要节点,发展国家气候观象台的观测能力,并依托其开展有特色的科学研究,有助于推动我国大气科学发展。深圳国家气候观象台是我国珠三角经济圈环境综合观测区唯一的国家级气候观象台,经过20余年的持续不断建设,已具备了城市—郊区的对比监测、气象—环境的联合监测、地面—高空的立体监测和陆地—海洋的协同监测等多方面的监测能力。基于深圳国家气候观象台的观测数据,大气科学领域的学者们已在粤港澳大湾区城市气候、边界层风特性及致灾机理、大气环境与环境气象、气候资源、地闪雷电特征等多个领域开展研究并取得了丰硕的成果,进一步丰富了对这些领域的科学认识。此外,深圳国家气候观象台还支撑了深圳本地的防灾减灾、城市管理、城市规划以及生态文明建设等工作,已逐渐成为发挥气象观测社会效益的典范。

Glacier area change and its impact on runoff in the Manas River Basin,Northwest China from 2000 to 2020

Understanding the distribution and dynamics of glaciers is of great significance to the management and allocation of regional water resources and socio-economic development in arid regions of Northwest China.In this study,based on 36 Landsat images,we extracted the glacier boundaries in the Manas River Basin,Northwest China from 2000 to 2020 using eCognition combined with band operation,GIS(geographic information system)spatial overlay techniques,and manual visual interpretation.We further analyzed the distribution and variation characteristics of glacier area,and simulated glacial runoff using a distributed degree-day model to explore the regulation of runoff recharge.The results showed that glacier area in the Manas River Basin as a whole showed a downward trend over the past 21 a,with a decrease of 10.86%and an average change rate of–0.54%/a.With the increase in glacier scale,the number of smaller glaciers decreased exponentially,and the number and area of larger glaciers were relatively stable.Glacier area showed a normal distribution trend of increasing first and then decreasing with elevation.About 97.92%of glaciers were distributed at 3700–4800 m,and 48.11%of glaciers were observed on the northern and northeastern slopes.The retreat rate of glaciers was the fastest(68.82%)at elevations below 3800 m.There was a clear rise in elevation at the end of glaciers.Glaciers at different slope directions showed a rapid melting trend from the western slope to the southern slope then to the northern slope.Glacial runoff in the basin showed a fluctuating upward trend in the past 21 a,with an increase rate of 0.03×10^(8) m^(3)/a.The average annual glacial runoff was 4.80×10^(8) m^(3),of which 33.31%was distributed in the ablation season(June–September).The average annual contribution rate of glacial meltwater to river runoff was 35.40%,and glacial runoff accounted for 45.37%of the total runoff during the ablation season.In addition,precipitation and glacial runoff had complementary regulation patterns for river runoff.The findings can provide a scientific basis for water resource management in the Manas River Basin and other similar arid inland river basins.

悖论式领导对员工创新的影响——团队协作与员工跨界行为的跨层中介研究

团队领导该如何激发员工创新?从中国传统阴阳哲学的角度出发,基于悖论式领导的角色,提出悖论式领导的整体性认知将影响员工对工作角色的感知。通过对395位团队成员和39位团队领导的多时点配对数据进行分析,发现了悖论式领导对员工创新的双重影响路径。研究表明,在个体层面,悖论式领导将促进下属不仅关注内部还关注外界工作资源,提升员工跨界行为,从而促进员工创新;在团队层面,悖论式领导将促进员工不仅关注自身,还关注团队整体,提升团队协作行为,从而促进员工创新,且在团队竞争氛围高时尤为明显。本文所提出的悖论式领导影响员工创新的2条路径,丰富了悖论式领导理论以及员工创新管理理论,并可供团队领导借鉴。

A Model of the Sea-Land Transition of the Mean Wind Profile in the Tropical Cyclone Boundary Layer Considering Climate Changes

The tropical cyclone boundary layer(TCBL)connecting the underlying terrain and the upper atmosphere plays a crucial role in the overall dynamics of a tropical cyclone system.When tropical cyclones approach the coastline,the wind field inside the TCBL makes a sea-land transition to impact both onshore and offshore structures.So better understanding of the wind field inside the TCBL in the sea-land transition zone is of great importance.To this end,a semiempirical model that integrates the sea-land transition model from the Engineering Sciences Data Unit(ESDU),Huang's refined TCBL wind field model,and the climate change scenarios from the Coupled Model Intercomparison Project Phase 6(CMIP6)is used to investigate the influence of climate changes on the sea-land transition of the TCBL wind flow in Hong Kong.More specifically,such a semiempirical method is employed in a series of Monte-Carlo simulations to predict the wind profiles inside the TCBL across the coastline of Hong Kong under the impact of future climate changes.The wind profiles calculated based on the Monte-Carlo simulation results reveal that,under the influences of the most severe climate change scenario,slightly higher and significantly lower wind speeds are found at altitudes above and below 400 m,respectively,compared to the wind speeds recommended in the Hong Kong Wind Code of Practice.Such findings imply that the wind profile model currently adopted by the Hong Kong authorities in assessing the safety of low-to high-rise buildings may be unnecessarily over-conservative under the influence of climate change.On the other hand,the coded wind loads on super-tall buildings slightly underestimate the typhoon impacts under the severe climate change conditions anticipated for coastal southern China.

平台型领导对新经济企业商业模式创新的影响机理研究--基于社会信息加工理论视角

旨在研究平台型领导对新经济企业商业模式创新的影响机理,进而为新经济企业进行商业模式创新提供建议与指导。基于社会信息加工理论,将心理安全感、边界跨越行为与创新氛围引入到平台型领导作用于商业模式创新的框架中,构建了一个有调节的链式中介模型,通过问卷调查收集了247份有效数据,运用结构方程模型与Bootstrap相结合的方法进行实证检验。研究结果表明:平台型领导对商业模式创新具有显著的正向影响;心理安全感与边界跨越行为分别在平台型领导对商业模式创新的影响中起到部分中介作用,且二者在平台型领导对商业模式创新的影响中起到链式中介作用;创新氛围在边界跨越行为与商业模式创新的关系中起到调节作用,创新氛围在平台型领导、边界跨越行为与商业模式创新的中介关系中起到调节作用;创新氛围在平台型领导、心理安全感、边界跨越行为与商业模式创新的链式中介关系中起到调节作用。在此基础上,研究为新经济企业如何利用平台型领导推进商业模式创新提出了相关建议。

基于站点数据分析中国大陆区域喜凉/温作物界限温度的时空演变

喜凉/温作物界限温度的时空分布能够影响作物物候和种植区域。利用全国585个气象站点1961-2020年地面气象观测资料,以喜凉/温作物界限温度(0℃和10℃)的积温、初日、终日作为农业热量资源研究指标,基于ANUSPLIN气象插值软件,从年际和年代际时间尺度分析1961-2020年喜凉/温作物界限温度的时空演变特征,并探讨热量资源变化对全国农业生产格局的影响。结果表明:受纬度和地形影响,全国热量资源变化幅度较大,东部地区≥0℃、≥10℃积温随纬度变化呈阶梯状分布,而在西部地区主要受海拔影响,总体表现为由南向北逐渐递减。各地≥0℃和≥10℃积温范围分别为700.0~8960.0℃·d和46.3~8960.0℃·d,≥0℃和≥10℃积温气候倾向率平均为72.8℃·d·10a^(-1)和73.7℃·d·10a^(-1)。60a内,界限温度0℃、10℃初日分别提前9.6d和8.4d,终日分别推迟4.8d和7.8d。界限温度初日的提前和终日推迟使60a内日平均气温≥0℃和≥10℃的持续日数分别增加14.4d和16.2d。2011-2020年是研究时段内最温暖10a,与P1时段(1961-1970年)相比,P6时段(2011-2020年)≥0℃和≥10℃积温平均值分别增加了6.3%和8.2%。P6时段≥0℃积温为6000~7000℃·d的区域面积增加了2.11×10^(5)km^(2);≥10℃积温为5000~6000℃·d的区域面积增加了3.37×10^(5)km^(2)。气候变暖背景下,活动积温增加对农业系统产生了重要影响,农业生产布局以及种植制度应及时做出调整,充分适应气候变化。

基于重力卫星数据探测核幔边界动态过程信号

使用GRACE(GravityRecoveryandClimate Experiment)重力场数据,联合多源数据模型剔除地表过程的重力信号,以分离得到核幔边界处包含液态外核流体运动特征的重力信号,同时根据CHAOS-7地磁场模型重建核幔边界与地球表面的地核地磁场变化,以此为基础使用主成分分析(PCA)与独立主成分分析(ICA)方法对重力信号与磁场信号进行统计分解,得到2种信号的时变模态与空间模态,对比分析2种信号分解结果的相关性,研究表明,重力信号第3模式的时变模态与磁场信号第2模式的时变模态相关性较好,同时,其空间模态反映了太平洋低纬度地区较为明显的东西向“偶极子”形式的变化特征,与地磁场二阶导数在太平洋地区的空间变化特征相对应,在2014年以后重力信号的时变模态与磁场信号二阶导数的时变模态均表现出相同的线性快速变化特征,与现有的研究成果相符合。

Impacts of Climate Change on Growth Period and Planting Boundaries of Spring Wheat in China under RCP4.5 Scenario

This article contributes to research on how climate change will impact crops in China by moving from ex-post empirical analysis to forecasting. We construct a multiple regression model, using agricultural observations and meteorological simulations by GCMs, to simulate the possible planting boundaries and suitable planting re- gions of spring wheat under RCP4.5 scenario for the base period 2040s and 2070s. We find that the south bound- ary of possible planting region for spring wheat spreads along the belt： south Shandong-north Jiangsu-north Anhui-central Henan-north Hubei-southeast Sichuan-north Yunnan provinces, and will likely move northward under RCP4.5 scenario in 2040s and 2070s, resulting in the decrease of possible planting area in China. Moreover, the sowing and harvest date of spring wheat in the base period shows a gradually delayed phenomenon from the belt： south Xinjiang - Gansu, to the Tibet Plateau. As a result, the growth period of spring wheat in China will shorten because of the impacts of climate change. These results imply that a variety of adaptations measures should be set up in response to changing climatic conditions, including developing the planting base for spring wheat, restricting the planting area of spring wheat in sub-suitable areas at risk while expanding the planting area of optimal crops.

TraCE-21ka的模拟评估及误差分析

TraCE-21ka是全球首个利用全耦合模式针对末次盛冰期(LGM)至今气候演变的瞬变模拟。利用现代再分析资料和历史特征时期重建的连续冻土边界对TraCE-21ka模拟做了评估。结果表明TraCE-21ka能够较好地模拟现代半球尺度环流和降水的空间形态,对东亚地区的模拟冬季较好而夏季欠佳。TraCE-21ka模拟的现代时期与再分析资料相比偏冷,北半球年平均表面温度比再分析资料低3~4℃,基于现代温度误差的分析表明TraCE-21ka对东亚地区气候演变的模拟欠佳。对于历史特征时期,重建的连续冻土边界线指示TraCE-21ka模拟的亚欧大陆在LGM偏暖,全新世中期偏冷,即低估了LGM以来的变温幅度。利用连续冻土边界线的年均表面温度约为-7℃这一特性,进一步定量评估出TraCE-21ka模拟的亚欧大陆中纬地区从LGM至今的升温幅度约为真实气候的40%。通过分析近百年全球升温速率证实TraCE-21ka的气候敏感性显著偏低,由此产生的误差在瞬变模拟中会不断累积。

Climate warming and its impact on natural regional boundaries in China in the 1980s

The global climate warming accelerated in the 1980s has become a focus in the world. Based on the month by month and year by year temperature data from 160 representative stations throughout the country during 1951-1999, this paper analyses annual and four seasons’ temperature variations of China since the 1980s. It was found out that the non-equalibrium response with relative great regional and seasonal differences is represented in the country’s climate warming. In regional changes a trend of “warm in the north and cold in the south” occurs whereas in seasonal changes, the characters of “warm in winter and cool in summer” present. Significant verification of the temperature variations conducted in terms of mathematical statistics reveals that a confidence level of over 95% has been basically reached in areas north of the Yangtze River. Meanwhile, according to data of diurnal mean temperature steadily passing through accumulated temperature ≥10°C from 335 stations since 1951 or since the founding of the stations in the early 1950s to 1999, comparative analysis of the data of the last 19 years with that of the first 30 years was conducted and the accumulated temperature ≥10°C and the variation range of the persistent number of days ≥10°C were obtained. It was concluded that a general northward shift of central subtropics, north subtropics, warm temperate zone, mesothermal zone and frigid temperate zone of eastern China was observed. The northward shift of north subtropics and warm temperate zone was obvious but changes of south subtropics and marginal tropics were insignificant. In western China, in addition to southwestern Yunnan, the Qinghai-Tibet Plateau and western Inner Mongolia where the temperature zones of each either shifted northward or trended to move upward, not much changes were found in other areas or they shifted southward slightly and declined.

温度层结对建筑风环境定量影响的大涡模拟

基于局地气候区分类,选取了北京门头沟地区4种局地气候区(高层开阔、高层密集、中层密集、稀疏建筑)作为研究对象,利用高分辨率大涡模拟方法,数值研究温度层结效应对不同局地气候区风和湍流特性的影响。2019年11月7日晴天小风个例模拟结果表明:1)温度层结对湍涡的形状和范围有显著影响。在近地面水平剖面上,稳定层结下涡旋数量较中性层结情况减少,但涡旋的纵向延伸范围可增大67%;不稳定层结下涡旋数量较中性层结增加,涡旋的纵向范围可缩小60%。在垂直剖面上,相较于中性层结,稳定层结下环流结构减弱且涡旋的纵向范围可缩小40%,不稳定层结下环流结构增强且涡旋的纵向范围可增大20%,该现象在高层密集型地块最为明显。2)4种局地气候区的风速的高值区主要位于平行于盛行风方向的建筑物两侧及屋顶附近,热力作用对总风速有增益作用,近地面风速较入流风速可增加1.27~2.18倍。3)4种局地气候区湍动能的高值区主要位于建筑物底部拐角处和屋顶,不稳定层结下近地面的湍动能是中性层结的1.2~1.5倍,而稳定层结下是中性层结的0.5~0.8倍,即不稳定层结条件下浮力引起的热力湍流增强混合效率,而稳定层结条件下湍流运动受到抑制。4)相较于其他局地气候区,高层密集区域的建筑物底部风速较大,在不稳定层结下易形成较强的狭管效应,其街区峡谷最大风速是中层密集的1.5倍。

NUMERICAL SIMULATION OF THE INFLUENCE OF VEGETATION COVER FACTOR ON BOUNDARY LAYER CLIMATE IN SEMI-ARID REGION

A numerical model has been developed for simulating land-surface processes and atmospheric boundary layer climate of vegetation and desert in semi-arid region.Dynamically,thermal and hydrological processes take place in the atmospheric boundary layer.Vegetation and surface layer of soil are included in the soil-vegetation-atmosphere coupled system,in which,vegetation is considered as a horizontally uniform layer,soil is divided into 13 layers and the horizontal differences of variables in the system are neglected.The influence of local boundary layer climate by vegetation cover factor is simulated with the coupled model in the semi-arid region of Northwest China (around 38°N,105°E).Results indicate that due to significant differences of water and energy budgets in vegetation and desert region,the air is colder and wetter over the vegetation and correspondingly an obvious local circulation in the lower atmosphere is formed. Simulating results also show that maximum updraft and downdraft occur around the vegetation-desert marginal area,where the dynamical and thermodynamical properties of PBL (Planetary Boundary Layer) are uncontinuous.It is stronger at daytime,weaker and reverse at nighttime.In the simulation,the moisture inversion phenomena are analyzed.Finally.the influences of vegetation cover factor exchange on local boundary layer climate are simulated.The simulating results bring to light that water may be conserved and improved by developing tree planting and afforestation,and improving cover factor of vegetation in local ecoenvironment,and this is an important way of transforming local climate in arid and semi-arid area.Results indicate that the coupled model can be used to study the soil-vegetation-atmosphere interaction and local boundary layer climate.

THE FLUCTUATIONS OF DRY AND WET CLIMATE BOUNDARY AND ITS CAUSAL ANALYSES IN CHINA

Based on yearly precipitation and Φ20 evaporation pan data during 1951 to 1999 of 295 stations,the aridity index is calculated in this paper.According to the aridity index,the climatic regions in China are divided into three types:the arid zone,the semi-arid zone and the humid zone. Isoline 0.20 is the boundary between arid and semi-arid zones.Isoline 0.50 is the boundary between semi-arid and humid zones.The fluctuations of dry and wet climate boundaries are very substantial,have greatly regional difference,and have the features of the whole shifting along the same direction and of the opposite moving along the contrary direction over the past 50 years.The semi-arid zone is a transitional zone between humid and arid zones,a border belt of monsoon,and a susceptible zone of environmental evolution in China. In the period of the late 1960s to the early 1970s,remarkable change had occurred for dry and wet climate in China.It manifests significantly that climate is from wetter into drought in most regions of northern China.Moreover,drought has an increasing trend.The fluctuations of climatic boundaries and the dry and wet variations in climate have substantial inter-decadal features. The main factors affecting the dry and wet climate boundary fluctuations and the dry and wet variations of climate in China are East Asian summer monsoon,Indian Monsoon,plateau monsoon in the Tibetan Plateau,westerly circulation,and West Pacific subtropical high.The different types of circulations and the strong and weak combinations of these circulations result in the regional differences of dry and wet climate changes in China.Inter-decadal variations of the dry and wet climate boundary fluctuations and of the arid and humid climate result from the inter-decadal changes of East Asian summer monsoon,Indian Monsoon,plateau monsoon,westerly circulation, and West Pacific subtropical high.The anomalous general atmospheric circulation in the Northern Hemisphere during the late 1960s to the early 1970s is the causes of arid and humid climate remarkable change in China.