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Analyzing Precipitation Characters of South and North China Based on the Exponent of Scaling Law

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Analyzing Precipitation Characters of South and North China ...

中国数学力学物理学高新技术交叉研究会第11届学术研讨会

作者： Gong Zhi-qiang~1 Feng Guo-lin~2 Zhi Rong~2 Zhang Da-quan~2 1.Department of Physics Yangzhou University,Yangzhou 225009,China 2.Laboratory for climate Studies,national climate {3.,China Meteorological Administration,beijing 100081,China

＜正＞In light of the recent research achievements of nonlinear science and in the context of the daily precipitation data from 1956 to 2000 at 20 stations in south and north China compiled by the national climate center,we calculated the exponents of power-law tail（EPT）on the cumulative distribution of probability of finding segment with lengths larger than l for each station’s precipitation time series based on BG algorithm, try to analyze the characters of precipitation both in south and north China from a new *** results show that power-law decay（scaling law）of the distribution of the stationary period may be a common occurrence for precipitation and other nonstationary time series;The distribution of EPT for precipitation might be different from area to area,and north China（NC）is comparing lager than south China（SC）;Meanwhile,The exponents of power-law tail（EPTs）might be another effective way to study the abrupt changes contained in nonlinear and nonstationary time series.

关键词： precipitation the exponent of power-law tail abrupt precipitation change grade

Frequency of extreme high temperature days in China,1961-2003

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Frequency of extreme high temperature days in China,1961-200...

“2010年北京气象学会中青年优秀论文评选”学术研讨会

作者： F.Zhang,~1 H.Gao~2 and X. Cui~3.1 national Meteorological center,CMA, beijing,China 2 Laboratory of {3. Study,CMA, beijing,China 3.Department of Geography,University of Liverpool,UK

Extreme weather and climate events have received much attention in the last few years, due to the large loss of human life and increasing financial costs often associated with them(Karl and Easterling,1999).Therefore, detection of changes in the frequency of these events has been one of the main themes of current climate research,especially under global warming ***, trends in the frequency of these events are quite diverse,both spatially and temporally (a brief review can be found in Easterling et al.,2000).Among extreme climate events,

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The relationship between spatial extent and duration of severe droughts in China over the last 50 years

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The relationship between spatial extent and duration of seve...

2010 Second IITA International Conference on Geoscience and Remote Sensing (IITA-GRS 2010)

作者： ZHANG Da-quan College of Atmospheric Sciences Lanzhou University Lanzhou China 73.000FENG Guo-lin Laboratory for climate Studies national climate {3. China Meteorological Administration beijing China 100081

Correlation between spatial extent and duration of severe droughts process and its statistical law is analyzed using Palmer Drought Severity Index （PDSI） through a newly developed system of drought process monitoring. Results indicate that during the period from late 1990s to early 2000s,the percentage of severe drought （PDSI＜-3.0） in China is unprecedented since 1960 under the background of global warming and the variation of the distributions of droughts coverage areas in different seasons is uneven. The distribution of spatial extent and durations of severe droughts follows a power-law,e.g. the spatial-temporal characteristics of severe droughts is independent to their scaling,namely,being scale free. In general the area of severe droughts is correlated closely with its duration,while the deviations of the linear fit from its correlation is also high.

关键词： drought duration distribution power-law

Correlations between North Atlantic Oscillation Index in winter and eastern China Flood/Drought Index in summer in the last 53. years

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Chinese Science Bulletin 2005年第21期50卷 2505-2516页

作者： FU Congbin & ZENG Zhaomei Key Laboratory of Regional climate-Environment for Temperate East Asia, Institute of Atmospheric Physics, Chinese Academy of Sciences START Regional center for Temperate East Asia, beijing 100029, China Key Laboratory of Regional climate-Environment for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences START Regional Center for Temperate East Asia Beijing 100029 China

The time series of winter North Atlantic Oscil-lation Index (NAOI) in the period of 1429-1983.developed by Glueck and summer Flood/Drought Index (FDI) of eastern China in the period of 1470-1999 from 100 stations are used in this paper to study the potential impact of North Atlantic Oscillation on the climate in China. The analysis has ex-plored some significant lag correlations between FDI and NAOI. The maximum positive correlation coefficients be-tween NAOI and area-mean FDI in eastern and northern China lagging 2-3.years reach at 0.001 significance level, and while there are also negative correlation between NAOI and FDI in central and southern China at significance level of 0.05-0.01. The correlation between FDI and NAOI is time-dependent, i.e. the correlation coefficients between two indices vary from period to period. The highest correlation appeared in the period of 163.-1742, around the Little Ice Age, with the significant level of far above 0.001. The second significant period was from 1951 to 1999, at the level of 0.005-0.002. Both the power spectrum analysis and Morlet wavelet transformation have presented an interesting phe-nomenon: the area-mean FDIs in eastern and northern China share almost the same oscillation periods with NAOI in the inter-annual, decadal and centurial scales’ oscillations, i.e. 4-5, about 10, 20-3., around 50 and 80-100 years, etc. The Mann-Kendall Rank Statistic test reveals the significant trend and decadal abrupt changes in the series of area-mean FDIs in eastern and northern China in the past 53. years, while the NAOI in the past 400 years, did not show such trend at the significance level, but presented more frequent changes than those of FDI in China. This difference is per-haps due to the fact that the amplitude of the extremes of reconstructed NAOI series is less than that from instrumen-tal records.

关键词：中国洪水干旱气候变化大西洋振动系数

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Interdecadal trend turning of global terrestrial temperature and precipitation during 1951-2002

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Progress in Natural Science:Materials International 2008年第11期18卷 1383-1393页

作者： Xiaohui Shi Xiangde Xu State Key Laboratory of Severe Weather,Chinese Academy of Meteorological Sciences,beijing 100081,China State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China

A grid-by-grid counting of interdecadal trend turning(ITT)of annual mean surface air temperature(SAT)and total precipitation at 67,3.9 terrestrial grids in the period 1951-2002 is *** analysis of the last ITTs of SAT and total precipitation in the period,in the context of both occurrence time and linear trends after the breakpoint,indicates that a warming trend has become highly significant across most reagent of the world in the late 20th *** terrestrial grids have recorded an ITT of total precipitation in either the 1970s or 1980s,and 45.7% of the terrestrial grids in the study have seen a decreasing trend in total annual precipitation after the break- point,with the remaining 54.3. having experienced an increasing ***,global terrestrial regions have experienced either an increasingly warm and dry climate or an increasingly warm and wet *** analysis of ITT of regional mean SAT and total pre- cipitation in 22 regions shows that the Northern American continent has become increasingly warm and dry after the last interdecadal ***,the African continent has become increasingly warm and wet,with both Europe and most of Asia having the same *** South America and the West of Australia have experienced an opposite trend in climate,becoming increasingly cold and wet.

关键词： Global terrene Surface air temperature Precipitation Interdecadal trend turning

Meteorological observations on Mount Everest in 2005

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Progress in Natural Science:Materials International 2007年第7期17卷 828-837页

作者： Xie Aihong~(1**) Qin Dahe~1 Ren Jiawen~1 Qin Xiang~1 Xiao Cunde~(1,2) Hou Shugui~1 Kang Shichang~(1,3. Yang Xingguo~(1,4) Jiang Youyan~1 (1.Key Laboratory of Cryosphere and Environment,Cold and Arid Regions Environment and Engineering Research Institute,Chinese Academy of Sciences,Lanzhou 73.000,China 2.Chinese Academy of Meteorological Science,beijing 100081,China 3.Institute of Tibetan Plateau Research,Chinese Academy of Sciences,beijing 100085,China 4.Gansu Provincial Meteorological Bureau,Lanzhou 73.000,China) Key Laboratory of Cryosphere and Environment Cold and Arid Regions Environment and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

Mount Everest,the highest point on the Earth is often referred to as the earth's third pole as such the place is relatively inaccessible and little is known about its *** April 2005,an automatic weather station was installed at the mountain's North Col(6523.m a.s.l.).According to the observational 10-minute mean and daily records,the meteorological characteristics were analyzed. All the meteorological elements displayed obvious diurnal variations during May 1 to July 22,*** monthly variation of daily meteo- rological elements on Mount Everest coincided with that on Dingri,the closest routine meteorological station,with the high correlation co- efficients of 0.928,0.877,0.682,0.755,0.826 and 0.676(n=83.p3.0.485 and 0.487(n=83.pclimate changes in the region.

关键词： Mount Everest meteorological observation Dingri County radiation air temperature relative humidity air pressure wind

Possible effect of solar activity on variation of the tree-rings of a 500 a platycladus orientalis at the Mausoleum of Emperor Huang

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Science China(Physics,Mechanics & Astronomy) 2009年第4期52卷 631-639页

作者： FENG Bo1,2 & HAN YanBen1 1 Xi’an Institute of Posts & Telecommunications,Xi’an 710061,China 2 national Astronomical Observatories,Chinese Academy of Sciences,beijing 100012,China Xi’an Institute of Posts & Telecommunications Xi’an China national Astronomical Observatories Chinese Academy of Sciences Beijing China

The variation of the tree-ring's index of a platycladus orientalis at the Mausoleum of Emperor Huang and of a long series of sunspots relative number during AD1470-1974 are analyzed by using the wavelet power spectrum method,and their variation characters are also discussed. It is determined that the tree-ring's variation has cycles of approximate 2-7,11,93.and 150 a. Two data series are used for analyzing sunspot relative number(SSN) variation. First,the analysis of the annual average SSN during AD1700-1974 proved that variation cycles are about 11,50,and 93.a; then,the data during AD1465-1975 obtained from the decadal average SSN train over 7000 a reconstructed on the geomagnetic data is analyzed and its variation cycles are about 50,90,and 160 a. Besides the tree-rings cycle of 2-7 a is commonly considered to be related to ENSO,while 11 a cycle is related to solar Schwabe cycle; in addition,it is possible that the cycles of 90 and150 a are likely to be related to solar Gleissberg cycle and Suess cycle. The correlations between them are possibly due to the effect of solar activity on the climate and additionally on the tree's growth.

关键词： tree-ring solar activity climate change wavelet spectrum

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Effect of non-spherical dust aerosol on its direct radiative forcing

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Effect of non-spherical dust aerosol on its direct radiative...

强化科技基础推进气象现代化——第29届中国气象学会年会

作者： Zhili Wang a,Hua Zhang b,Xianwen Jing a,b,Xiaodong Wei c a Chinese Academy of Meteorological Sciences,beijing 100081,China b Laboratory for climate Studies,{3. climate center,China Meteorological Administration,beijing 100081,China c Meteorological center,East China Bureau of Air Control,Shanghai 201702,China

The optical properties of spherical and non-spherical dust aerosols are calculated using the Lorenz-Mie theory and the combination of T-matrix method and an improved geometric optics *** resulting optical properties are then applied in an interactive system that coupled a general circulation model with an aerosol model to quantitatively analyze the effect of non-spherical dust aerosol on its direct radiative forcing(DRF).Our results show that the maximum difference in dust instantaneous radiative forcing(IRF) between spherical and non-spherical particles is 0.27 W m-2 at the top of the atmosphere(TOA) and appears over the Sahara Desert due to enhanced absorption of solar radiation by non-spherical *** global annual means of shortwave(longwave) IRFs due to spherical and non-spherical dust aerosols at the TOA for all sky are-0.62(0.074) W m-2 and-0.61(0.073. W m-2,respectively,and the corresponding values for clear sky are-1.16(0.092) W m-2 and-1.14(0.093. W m-2,which indicates that the non-spherical effect of dust has almost no effect on their global annual mean ***,non-spherical dust displays more evident influences than above on its atmospheric-and land-temperature adjusted radiative forcing(ARF) at the TOA over the Saharan Desert,West Asia,and northern China,with an approximate maximum increase of 3.0 and decrease of 0.5 W *** global annual means of shortwave(longwave) ARFs due to spherical and non-spherical dust aerosols are-0.55(0.052) W m-2 and-0.48(0.049) W m-2 at the TOA for all sky,respectively,and the corresponding values for clear sky are-1.07(0.066) W m-2 and-0.95(0.062) W *** ARFs of dust become much weaker than their corresponding *** absolute values of annual mean ARF for non-spherical dust are approximately 13.(11.2%) and 6%(6%) less than those of spherical dust for the shortwave and longwave for all sky(clear sky),*** results indicate that the non-spherical effect of dust can reduce their ARFs more obvio

关键词： Dust Spherical/Non-spherical Particles IRF ARF

Turbulent intensity and its similarity function over an Inner Mongolian grassland during spring

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Science China Earth Sciences 2010年第5期53卷 773-780页

作者： YUE Ping1,2,3. NIU ShengJie2, HU YinQiao4 & ZHANG Qiang1 1 Key Laboratory of Arid climate Change and Reducing Disaster of Gansu Province, Key Laboratory of Arid climate Change and Reducing Disaster of CMA, Institute of Arid Meteorology, CMA, Lanzhou 73.020, China 2 Nanjing University of Information Science and Technology, Nanjing 210044, China 3.Zhangye national Meteorological Observatory, Zhangye 73.000, China 4 Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Science, Lanzhou 73.000, China Key Laboratory of Arid climate Change and Reducing Disaster of Gansu Province Key Laboratory of Arid Climate Change and Reducing Disaster of CMA Institute of Arid Meteorology CMA Lanzhou China Nanjing University of Information Science and Technology Nanjing China Zhangye national Meteorological Observatory Zhangye China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Science Lanzhou China

Macroscopic reason for the development of turbulences in fluid is the conjunction action of velocity and temperature shears. We use the 2008 spring flux observations in the surface layer over Inner Mongolian grassland, obtain the similarity functions of turbulent intensity under different stratification stability conditions, and calculate the clear day turbulent intensity in the spring, which is then analyzed and compared with the observed values of turbulent intensity. The results show that in the Inner Mongolian grassland, under the condition of spring unstable stratification of the surface layer, dependence of the similarity function of turbulent intensity on stratification stability follows a "2/3.power law". The structural function is a constant under the neutral stratification condition, and complicated under the stable condition. The calculated turbulent intensity has a close correlation with the observed one, which verifies the accuracy of the similarity functions and the suitability of the theorem of turbulent intensity in the grassland region.

关键词： turbulent intensity variance of velocity similarity function grassland

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