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Regional soil moisture simulation for Shaanxi Province using SWAT model validation and trend analysis

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Science china Earth Sciences 2010年第4期53卷 575-590页

作者： LI MingXing1,2,MA ZhuGuo1 & DU JiWen3 1 Key Laboratory of Regional climate-Environment Research for Temperate East Asia,Institute of Atmospheric Physics,Chinese Academy of Sciences,beijing 100029,china 2 Graduate University of Chinese Academy of Sciences,beijing 100049,china 3 Shaanxi Administration of Meteorology,Xi’an 710014,china 1. Key Laboratory of Regional climate-Environment Research for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Shaanxi Administration of Meteorology Xi’an 710014 China

The soil moisture in Shaanxi Province,a region with complex topography,is simulated using the distributed hydrological model Soil Water Assessment Tool(SWAT).Comparison and contrast of modeled and observed soil moisture show that the SWAT model can reasonably simulate the long-term trend in soil moisture and the spatiotemporal variability of soil moisture in the *** to NCEP/NCAR and ERA40 reanalysis of soil moisture show that the trend of variability in soil moisture simulated by SWAT is more consistent with the *** model results suggested that high soil moisture in surface soil layers appears in the southern Shaanxi with high vegetation cover,and the Qinling mountainous region with frequent orographic *** deeper soil layers,high soil moisture appears in the river basins and *** regional soil moisture showed a generally decreasing trend on all soil layers from 1951 to 2004,with a stronger and significant decreasing trend in deeper soil layers,especially in the northern parts of the province.

关键词： SWAT soil moisture content simulation validation trend analysis

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Simulation of 1991-2005 Meiyu seasons in the Yangtze-Huaihe region using BCCRegCM 1.0

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Simulation of 1991-2005 Meiyu seasons in the Yangtze-Huaihe ...

第七届全国优秀青年气象科技工作者学术研讨会

作者： HU YaMin1,2 DING YiHui3 1 Guangdong climate center, Guangzhou 510080, china 2 Institute of Tropical and Marine Meteorology, china Meteorological Administration, Guangzhou 510080, china 3 national climate center, china Meteorological Administration, beijing 100081, china

By using BCCegCM 1.0 (RegCM for short) from beijing climate center (BCC), china Meteorological Administration (CMA), the Meiyu season characters over the Yangtze-Huaihe region during 1991～2005 are simulated. The major conclusions of this study may be summarized as the following: (1) RegCM can reproduce the interannual variation and the spatial distribution of the summertime precipitation and temperature in the Yangtze-Huaihe region. (2) By use of a generalized Meiyu criterion and in accordance with model-calculated precipitation and temperature, the Meiyu onset and ending date have been determined. Compared with the observation, RegCM can simulate the interannual variation of the Yangtze-Huaihe Meiyu with preferable capability for most of the normal Meiyu years (such as 1995, 1997, 2000, 2001, 2002 and 2004), especially for the rich Meiyu years of 1996, 1998 and 1999. (3) In terms of the average simulation for the recent 15a, the timings of onset and ending of Meiyu occur on June 1 and July 13, respectively, which are earlier than the climatological observation. For duration, Meiyu persists for 32 day, 3 days shorter than the observation. The index of Meiyu intensity is 2.45, while the climatological one is 3.00. Therefore, RegCM is capable of simulating the climatological Meiyu duration and intensity, while the capability of simulating the onset and ending date of Meiyu still needs to be improved.

关键词： regional climate model Meiyu in Yangtze-Huaihe region Meiyu onset Meiyu ending Meiyu rainfall

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 67,359 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

Evolution of terraces Ⅰ–Ⅲ along the Anning River, western Sichuan, based on pollen records and terrace structure

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Science china Earth Sciences 2011年第1期54卷 127-135页

作者： CHENG JianWu1,2 1 Institute of Geology, china Earthquake Administration, beijing 100039, china 2 Earthquake Administration of Gansu Province, Lanzhou 730000, china Institute of Geology China Earthquake Administration Beijing China Earthquake Administration of Gansu Province Lanzhou China

This study reconstructs the long-term evolution of river terraces over large spatial scales along the Anning River, western Sichuan, and identifies external factors controlling terrace formation. Pollen record analysis and terrace structure indicate that formation of the middle section of terraces I-III resulted from the interaction of changing climates and uplift of the margins of the Qinghai-Tibet Plateau. The relative influence of climate and uplift in terrace formation changes in different periods. The terraces reveal multiple, gradual uplift events on the eastern Qinghai-Tibet Plateau, which is of great significance for determining uplift mechanisms across the entire plateau.

关键词： Anning River in western Sichuan terrace formation pollen paleoclimate

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An improvement on summer regional climate simulation over East china: importance of data assimilation of soil moisture

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An improvement on summer regional climate simulation over Ea...

第七届全国优秀青年气象科技工作者学术研讨会

作者： HU YaMin1, 2, DING YiHui3 & LIAO Fei2 1 Guangdong climate center, Guangzhou 510080, china 2 Institute of Tropical and Marine Meteorology, china Meteorological Administration, Guangzhou 510080, china 3 national climate center, china Meteorological Administration, beijing 100081, china

The Newtonian relaxation is used to assimilate data from the Second Global Soil Wetness Project (GSWP2) into the initial field for soil moisture in a regional climate model (i. e., BCCegCM 1.0, hereinafter called RegCM). The results show that different nudging parameters can improve the simulation of the air temperature and the precipitation to some extent in summertime sea-son over East china. When the nudging intensity is 0.5 and nudging duration is 5 days, the result is desirable. Introducing the data assimilation of soil moisture into RegCM, the amelioration is not only in the spatial distribution pattern but also in the mag-nitude of the temperature and the precipitation. More specifically, the assimilation experiments have corrected the systematical cold bias of the air temperature and the precipitation on the low side, which is much closer to the observation compared with the control experiment. On the whole, the assimilation experiments shed light on the fact that the simulated bias in the original RegCM may be affected by the description of soil moisture in the land surface process. Therefore, the effect of soil moisture in RegCM should be paid more attention in the future.

关键词： soil moisture Newtonian relaxation data assimilation regional climate simulation

Change in Extreme Temperature Event Frequency over china's mainland during 1961-2008

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Change in Extreme Temperature Event Frequency over China's m...

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： Yaqing Zhou 1,2 Guoyu Ren 2,1 Jinzhong Meteorological Bureau of Shanxi Province,Jinzhong 030600,china 2 Laboratory for climate Studies,national climate center,china Meteorological Administration(CMA),beijing 100081,china

利用 526 个国家级气象站 1961～2008 年的日最高、最低气温资料,分析了中国大陆地区气温极端事件的变化规律。结果表明,中国大陆地区霜冻日数和结冰日数明显减少,结冰日数减少显著的区域集中在北方,霜冻日数则在整个中国区域都显著减少... 详细信息

利用 526 个国家级气象站 1961～2008 年的日最高、最低气温资料,分析了中国大陆地区气温极端事件的变化规律。结果表明,中国大陆地区霜冻日数和结冰日数明显减少,结冰日数减少显著的区域集中在北方,霜冻日数则在整个中国区域都显著减少,夏季日数和炎热夜数明显增多,增多显著的区域主要在长江中下游和西南地区南部。日最高(低)气温的极大(小)值整体都有上升趋势,最高(低)气温的极大值在北方上升较明显,而在长江中下游和西南地区有下降的趋势;最高(低)气温的极小值则在全国范围都呈明显上升,极端最低气温上升尤为显著。冷夜 (昼)日数普遍明显减少,48 年中减少趋势为 8.23 d.(10 yr)-1[3.26 d.(10 yr)-1];暖夜(昼)日数明显增加,增加趋势为 8.16 d.(10 yr)-1[5.22 d.(10 yr)-1]。冷夜(昼)日数减少主要发生在冬季,其次是春、秋季,而暖昼和暖夜日数增加最显著的季节分别出现在秋季和夏季。从转折时间上看,极端气温指数的冷指是从 20 世纪 80 年代中后期开始显著减少的,暖指显著增加的时间则推迟到 20 世纪 90 年代中期。华北区域的研究结果表明,对于和最低气温有关的极端指数而言,城市化有显著影响,它加剧了冷指数的减少和暖指数的增加,国家站极端指数趋势变化中有 4 成以上是城市化造成的。另外城市化对气温日较差的影响也十分显著,近 48 年中国家站气温日较差的趋势变化基本上都是由城市化造成的。城市化对极端气温指数的影响不容忽视。

关键词：极端气温指数最高气温最低气温气候变化中国大陆

A severe drought event in northern china in winter 2008-2009 and the possible influences of La Nina and Tibetan Plateau

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A severe drought event in northern China in winter 2008-2009...

“2010年北京气象学会中青年优秀论文评选”学术研讨会

作者： Hui Gao and Song Yang 1 national climate center,china Meteorological Administration, beijing,china. 2 climate Prediction center,NOAA,Camp Springs,Maryland,USA.

Severe drought occurred in northern china in winter 2008-09 and the La Nina event might have exerted a major influence on the *** correlation analysis and case investigation indicate that severe wintertime droughts in northern china mostly occur under La Nina *** La Nina event in 2008-2009 increased the differences in temperature and atmospheric pressure between the Indo-Pacific Oceans and the Asian continent and intensified the northeasterly East Asian winter monsoon *** winter 2008-2009,the western Pacific subtropical high was located farther south than normal,associating with a southward shift of the Intertropical Convergence Zone so that wet and warm flow could hardly reach northern china from the tropical ***,the La Nina event in 2008-2009 strengthened the upstream portion of the upper tropospheric jet stream and the descending branch of the meridional cell over the subtropics,causing a negative divergence anomaly to the northern side of the jet *** a result,the airflow over northern china is more convergent (divergent) at the upper(lower) levels,unfavorable for *** winter 2008- 2009,the surface and tropospheric temperatures over the Tibetan Plateau were above *** a result,the India-Burma trough was shallower and less active,weakening the moisture transportation from the Bay of Bengal to eastern *** feature was possibly related to the less snow over the *** also show that both the Nino3.4 SST and the Tibet Plateau temperature in the previous autumn can be considered indicators of the winter drought in northern china.

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Maximum Wind Speeds Changes over china

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Maximum Wind Speeds Changes over China

第28届中国气象学会年会

作者： JIANG Ying1,LUO Yong2,3,ZHAO Zongci2,3 1 Public Weather Service center of CMA,beijing 100081,china 2 center for Earth System Science of Tsinghua University,beijing,100084,china 3 national climate center of china,beijing,100081

An intensive analysis is undertaken for the characteristics of maximum wind speed（WSMax） change for 1956-2004 across china based on the observed station data,with further study of the changes of WSMax for 2046-2065 and 2080-2099 as projected by three global climate models（GFDLM2,CCCMAGCM3 and MRIGCM2） and their ensembles which proposed in the IPCC Fourth Assessment Report（AR4） . It is found that the observed annual and seasonal WSMax and the number of gale days show obviously the declining trends. The annual WSMax and the gale days reduced by about-1.46 m/s per decade and-3.0 days per decade during the study period 1956-2004,respectively. The amplitudes of annual and seasonal WSMax decreases were bigger than that of annual and seasonal average wind speeds（WSAvg） . Under the weakening of both East Asian winter and summer monsoons,the distinct decreases of WSMax associated with the weakening of cold wave in china and the decreasing number（weakening intensity） of landing typhoons in the northwestern Pacific Ocean. The global climate models GFDLM2,MRIGCM2 and EBGCM（the ensemble of GFDLM2,MRIGCM2 and CCCMAGCM3） areto project consistently that the annual and seasonal WSMax reduce during 2046-2065 and 2080-2099 to compare with 1981-2000,i.e. the WSMax for 2046-2065 decreases by-3.0m/s relative to 1981-2000. It is also noticed that the WSMax decreases during 2046-2065 and 2080-2099 have a good relationship with both the cold wave weakening as corresponding to the winter monsoon weakening and the decreasing numbers of tropical cyclones over the northwestern Pacific Ocean in the summer of the 21st century.

关键词： maximum wind speed,change,projection,china

Spatial patterns of ecosystem carbon residence time in Chinese forests

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中国科学：地球科学英文版 2010年第8期53卷 1229-1240页

作者： ZHOU Tao1,2, SHI PeiJun1,2, JIA GenSuo3, LI XiuJuan1,2 & LUO YiQi4 1 State Key Laboratory of Earth Surface Processes and Resource Ecology, beijing Normal University, beijing 100875, china 2 Academy of Disaster Reduction and Emergency Management, Ministry of Civil Affairs & Ministry of Education, beijing 100875, china 3 Key Laboratory of Regional climate-Environment Research for Temperate East Asia, Chinese Academy of Sciences, beijing 100029, china 4 Department of Botany and Microbiology, University of Oklahoma, Norman, OK 73019, USA 1. State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Beijing 100875 China2. Academy of Disaster Reduction and Emergency Management Ministry of Civil Affairs & Ministry of Education Beijing 100875 China3. Key Laboratory of Regional Climate-Environment Research for Temperate East Asia Chinese Academy of Sciences Beijing 100029 China4. Department of Botany and Microbiology University of Oklahoma Norman OK 73019 USA

Capacity of carbon sequestration in forest ecosystem largely depends on the trend of net primary production (NPP) and the length of ecosystem carbon residence time. Retrieving spatial patterns of ecosystem carbon residence time is important and necessary for accurately predicting regional carbon cycles in the future. In this study, a data-model fusion method that combined a process-based regional carbon model (TECO-R) with various ground-based ecosystem observations (NPP, biomass, and soil organic carbon) and auxiliary data sets (NDVI, meteorological data, and maps of vegetation and soil texture) was applied to estimate spatial patterns of ecosystem carbon residence time in Chinese forests at steady state. In the data-model fusion, the genetic algorithm was used to estimate the optimal model parameters related with the ecosystem carbon residence time by minimizing total deviation between modeled and observed values. The results indicated that data-model fusion technology could effectively retrieve model parameters and simulate carbon cycling processes for Chinese forest ecosystems. The estimated carbon residence times were highly heterogenous over china, with most of regions having values between 24 and 70 years. The deciduous needleleaf forest and the evergreen needleleaf forest had the highest averaged carbon residence times (73.8 and 71.3 years, respectively), the mixed forest and the deciduous broadleaf forest had moderate values (38.1 and 37.3 years, respectively), and the evergreen broadleaf forest had the lowest value (31.7 years). The averaged carbon residence time of forest ecosystems in china was 57.8 years.

关键词： carbon residence time carbon cycle forest ecosystem data-model fusion inverse modeling genetic algorithm

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