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Responses of soil respiration in non-growing seasons to environmental factors in a maize agroecosystem,Northeast china

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Chinese Science Bulletin 2010年第24期55卷 2723-2730页

作者： LI RongPing1,2,3, ZHOU GuangSheng1,4 & WANG Yu1,3 1 State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, china 2 Institute of Atmospheric Environment, china meteorological administration, Shenyang 110016, china 3 Graduate University of Chinese Academy of Sciences, Beijing 100049, china 4 Chinese Academy of meteorological Sciences, Beijing 100081, china State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China Institute of Atmospheric Environment China Meteorological Administration Shenyang 110016 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Chinese Academy of meteorological Sciences Beijing 100081 China

Based on continuous three-year measurements (from 2004 to 2007) of eddy covariance and related environmental factors, environmental controls on variation in soil respiration (Rs) during non-growing season were explored in a maize agroecosystem in Northeast china. Our results indicated that during non-growing seasons, daily Rs was 1.08-4.08 g CO2 m-2 d-1, and the lowest occurred in late November. The average Rs of non-growing season was 45..06 ± 20.01 g CO2 m-2, accounting for 11% of the gross primary production (GPP) of the growing season. Additionally, at monthly scale, the lowest value of Rs appeared in January or February. From the beginning to the end of non-growing season, daily Rs tended to decrease first, and then increase to the highest. There was a significant quadratic curve relationship between Rs and soil temperature at 10 cm depth when soil temperature was more than 0°C (P5.%-79%. Meanwhile, the standard error of regression estimation between the values of prediction and observation for Rs could reach 2.7%-11.8%. Rs in non-growing season can account for 22.4% of Rs in growing season, indicating that it plays a critical role in assessing the carbon budget in maize agroecosystem, Northeast china.

关键词：中国东北地区农田生态系统生长季节土壤呼吸环境因素玉米土壤含水量反应

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Detection of the Kuroshio frontal instable processes (KFIP) in the East china Sea using the MODIS images

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Acta Oceanologica Sinica 2010年第6期29卷 35-43页

作者： JIA Yongjun ZHANG Jie national satellite Ocean Application Service Beijing 100081 China First Institute of Oceanography State Oceanic Administration Qingdao 266061 China

The Kuroshio frontal instable processes （KFIP） in the East china Sea （ECS） not only have a great impact on the hydrologic characteristics,the pollutants drift,the distribution of seafloor sediment and the ships navigation of the ECS,but also are closely related to the climate changes of the coastal areas of the *** the frequency and area of occurrence of the KFIP have not been studied fully and *** of its high spatial and temporal resolution,MODIS data is a kind of very good data source for surveying and researching the KFIP in the *** aim of this study is to detect the KFIP in the ECS by using MODIS data,and to study the frequency and region of occurrence of the KFIP in the *** selection has coverage of level 2 data of MODIS SST and Kd490 ranging from July 1,2002 to June 30,2009 of the ECS when there was no cloud impact or *** using of the data,the minimum standard of the Kuroshio temperature fronts and the diffuse attenuation coefficient （Kd490） fronts of the ECS are *** on these standards and the curvature distinguish methods,the standard of curvature distinguish for the KFIP in the ECS are put *** making use of this standard,we study a total of 2073 satellite-derived images,and discover that as long as there is no cloud impact from January to May and October to December,the KFIP in the ECS are surely found in MODIS satellite *** June to September,the frequency of occurrence can also reach to 82.9% at ***,it is obtained that there are three source regions of these instability processes,namely,（26°N,121.5.E） nearby,（27°N,125.E） nearby and （30°N,128°E） *** differences of the characteristics of these instability processes which are generated in different regions are analyzed in the present study.

关键词： Kuroshio frontal instable processes frequency and region of occurrence East china Sea MODIS

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A Two-Moment Bulk Microphysics Coupled with a Mesoscale Model WRF:Model Description and First Results

A Two-Moment Bulk Microphysics Coupled with a Mesoscale Mode...

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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： Gao Wenhua 1,Zhao Fengsheng 1,Hu Zhijin 2,and Feng Xuan 1 1 national satellite meteorological center,china meteorological administration,Beijing 100081 2 Chinese Academy of meteorological Sciences,china meteorological administration,Beijing 100081

The Chinese Academy of meteorological Sciences(CAMS) two-moment bulk microphysics scheme was adopted in this study to investigate the representation of cloud and precipitation processes under different environmental *** scheme predicts the mixing ratio of water vapor as well as the mixing ratios and number concentrations of cloud droplets,rain,ice,snow,and graupel.A new parameterization approach to simulate heterogeneous droplet activation was developed in this ***,the improved CAMS scheme was coupled with the Weather Research and Forecasting model(WRF v3.1),which made it possible to simulate the microphysics of clouds and precipitation as well as the cloud-aerosol interactions in selected atmospheric *** rain event occurring on 27-28 December 2008 in eastern china was simulated using the CAMS scheme and three sophisticated microphysics schemes in the WRF *** showed that the simulated 36-h accumulated precipitations were generally agreed with observations,and the CAMS scheme performed well in the southern area of the nested *** radar reflectivity,the averaged precipitation intensity,and the hydrometeor mixing ratios simulated by the CAMS scheme were generally consistent with those from other microphysics *** hydrometeor number concentrations simulated by the CAMS scheme were also close to the experiential values in stratus *** model results suggest that the CAMS scheme performs reasonably well in describing the microphysics of clouds and precipitation in the mesoscale WRF model.

关键词： droplet activation two-moment bulk microphysics WRF coupling

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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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Chinese Science Bulletin 2010年第9期55卷 867-873页

作者： HU YaMin1,2,3, DING YiHui4 & LIAO Fei2 1 Institute of Tropical and Marine Meteorology, china meteorological administration, Guangzhou 5.0080, china 2 Guangdong Climate center, Guangzhou 5.0080, china 3 Chinese Academy of meteorological Sciences, Beijing 100081, china 4 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., BCC_RegCM 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 season 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 magnitude 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

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A LAI Inversion Algorithm Based on Directional Reflectance

A LAI Inversion Algorithm Based on Directional Reflectance

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中国气象学会2004年年会

作者： Tang Shihao~(12) (1 national satellite meteorological center, china meteorological administration, Beijing 100081,{5. 2 Remote Sensing and GIS Research center, Department of Geography, Beijing Normal University, Beijing 100875.{5.)

＜正＞Leaf area index (LAD is an important ecological and environmental parameter. The current remote sensing inversion methods of leaf area index can mainly（?）e grouped into two classes: vegetation index based methods and remote sensing physical model based methods. In this paper, a new LAI retrieval method is developed. The algorithm borrows ideas from the principles and methods of ground LAI measurements, and adopts a new frame which differs from traditional remote sensing LAI inversion methods. First, the relationship between LAI and directional gap fraction is derived from the definition of LAI. Then, directional gap fraction is acquired from remote sensing bidirectional reflectance distribution function （BRDF） product. This acquisition is obtained by the use of a kernel driven model and a large scale directional gap fraction algorithm. At last, the large scale LAI is calculated through angle integrations. This algorithm has been applied to get LAI distribution of china in the middle of July, 2002. The ground data acquired from two field experiments conducted in Changbai Mountain and Qiiian Mountain, china, are used to validate the algorithm. In order to resolve the scale change problem between high resolution grouad observation and low resolution remote sensing data, two high resolution remote sensing images almost ha, ing the same resolutions with ground measurements are used as transitions. In order to proceed, we first bulid an empirical relationship between measured LAI and high resolution reflectance. Then, we get high resolu ion LAI distribution according to that relation. The LAI value of a low resolution pixel is calculated from the areal weighted sum of high resolution LAIs composing the low resolution pixel. Our results show that the algo（?）ithm has a high precision. Factors that may influence the precision of the algorithm are also discussed in this paper.

关键词： LAI MODIS BRDF ALBEDO Gap fraction

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HISTORICAL DATABASE OF TYPHOON,STORM RAINFALL AND CYCLONE

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Natural Disaster Reduction in china 1996年第3期 132-138页

作者： Li Zhao-clang and Yak Xuexiang(national meteorological center, china Meteralogical administration, Beijing 100081 )

The study of historical database of typhoon, storm rainfall and cyclone belongs to the sub-project 09- 01 - 04- 03 of national Science and Technology Key Project 85. 906. It consists of five secondary bases: the database of tropical cyclone track and its strength in the Northwest Pacific, the precipitation database of tropical cyclone in china, the database of temperate cyclone track and its strength in china, the wind and rainfall database of temperate cyclone and the historical database of important storm rainfall process. The historical database has been set up on the computer and has strong transplanting feature. By adopting FoxBASE with Chinese words in designing management system of the database, it has function of figure display for precipitation data in graphs and being inquired 5.0 hpa height field data, it is convenient for reference in understanding the circulation pattern of precipitation process at the beginning, sustaining and ending stages. This paper will introduce to the structure, data, rule for choosing cases, using form and function of the historical database of typhoon, storm rainfall and cyclone.

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Variations of near-surface atmospheric CO_(2)and H_(2)O concentrations during summer on Muztagata

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Science china Earth Sciences 2006年第1期49卷 18-26页

作者： XU Baiqing1,2, YAO Tandong1,2, LU Anxin2, GUO Xuejun, LIU Xianqin2 & LI Zhen2 1. Laboratory of Environment and Process on Tibetan Plateau, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100085. china 2. Key Laboratory of Cryosphere and Environment, Jointly Established by Cold and Arid Regions Environmental and Engi-neering Research Institute and Institute of Tibetan Plateau Research, Chinese Academy of Sciences and Chinese Academy of meteorological Sciences, china meteorological administration, Lanzhou 730000, china 1. Laboratory of Environment and Process on Tibetan Plateau Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China 2. Key Laboratory of Cryosphere and Environment Jointly Established by Cold and Arid Regions Environmental and Engineering Research Institute and Institute of Tibetan Plateau Research Chinese Academy of Sciences and Chinese Academy of Meteorological Sciences China Meteorological Administration Lanzhou 730000 China

Expeditions during the summers of 2002 and 2003 implemented continuous monitoring of near-surface (2 m height) atmospheric CO2 and H2O concentrations at the 45.0 m elevation on Muztagata. The resultant data sets reveal a slight decrease of CO2 concentrations (of about 5.μmol·mol?1) and changes in the diurnal variations from the end of June to the middle August. The daily maximum CO2 concentrations occur between 02:30―05.30 AM (local time) and the minimum levels occur between 12:00―15.30 PM. The atmospheric CO2 concentrations in the summer of 2002 were around 5.μmol·mol?1 lower than those during the same period of 2003, whereas the diurnal amplitude was higher. In contrast, we found that the daily mean atmospheric H2O content in 2003 was much lower than that in 2002 and there exists a striking negative correlation between CO2 and H2O con-centrations. We therefore suggest that the near-surface atmospheric CO2 concentration is affected not only by photosynthesis and respiration, but also by the air H2O content in the glaciated region around Muztagata.

关键词： atmospheric CO2 and H2O concentration, continuous monitoring, glaciation region, Muztagata.

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Diagnosis of a Severe Rainstorm Event Induced by Eastly Wave and Vortex in Off Southeast Coast of china

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高原气象 2009年第5期28卷 1058-1066页

作者： ZHENG Feng1-3(1.Chinese Academy of meteorological Sciences,Beijing 100081,china 2.Nanjing University of Information Science & Technology,Nanjing 210044,china 3.Wenzhou meteorological Bureau,Wenzhou 325.27,china) Chinese Academy of meteorological Sciences 北京 100081

Using the NCEP reanalysis at 1°×1° resolution in conjunction with satellite imagery,a study is undertaken of easterly wave related rainstorm events on August 3~4,2001 in seaboards between northern Fujian and southern Zhejiang,expounding the scheme for computing helicity,and exploring the rainstorm evolution and the genesis of the Yandang mountains-triggered a meso-vortex(Duan and Chen,2005. by means of helicity and Q vector ***,MM5.2 is employed to simulate the easterly wave caused meso-vorte...

关键词： Easterly wave Meso-vortex Helicity Q vector MM5.modeling

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A three-dimensional model study on ocean dynamic response to traveling cyclone over the Huanghai Sea

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Acta Oceanologica Sinica 2005年第1期24卷 60-75页

作者： QINZenghao LIYongping YUANYaochu YURunling ShanghaiTyphoonInstitute ChinaMeteorologicalAdministrationShanghai200030China／／SecondInstituteofOceanographyStateOceanicAdministratianHangzhou310012China ShanghaiTyphoonInstitute ChinaMeteorologicalAdministrationShanghai200030China SecondInstituteofOceanography StateOceanicAdministratianHangzhou310012China／／KeyLaboratoryofOceanDynamicProcessesandSatelliteOceanographyofStateOceanicAdministrationHangzhou310012China

On the basis of numerical simulation of the mean circulation and relevant thermal-salinity fields in June with a three-dimensional o-cean model (ECOM-si), the model outputs are used as first guess of initial fields for numerical integration of the model equations and the numerical results are applied to investigating the dynamical responses of the Huanghai Sea and the East china Sea (HECS) in the course of a weak land-to-sea cyclone's passage over the Huanghai Sea on 15.16 June 1999. Predominance of the dynamic impact of cyclone over the thermal one in June in the HECS is justified using observations and model *** cyclone and its surrounding weather system, i.e., subtropical high ridge to its south could influence current and thermal fields in the Bohai Sea, the Huanghai Sea and the northern East china Sea even though the intensity of cyclone was rather weak. The response of oceanic currents to the wind stresses driven by the cyclone and its soumern subtropical high were strongly characterized by the wind drift with its extent of equivalent scale of cyclone in the horizontal and of Ekman layer in the vertical. The sea response at a given site was closely related to the transient local wind speed and *** was sensitive to the local wind direction,which is demonstrated at three points locating at the southern and western Huanghai Sea and the northern East china Sea. So the sea responses at locations differed considerably from one another. Current responded to the wind stress in a simple way:directly to the wind-driven current and subsequent gradient current and slope current, etc., whereas sea temperature responded to the wind stress in two ways: directly to the cyclone-induced cooling and indirectly to water movements both in the horizontal and the vertical by the cyclone' s wind stress. So the sea temperature variation under the influence of cyclone was more complicate than the current. The HECS in response to the cyclone and its ambient

关键词： sea response Huanghai Sea East china Sea Bohai Sea weak cyclone numerical study

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Debating about the climate warming

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Progress in Natural Science:Materials International 2006年第1期16卷 1-6页

作者： WANG Shaowu1, LUO Yong2, ZHAO Zongci2, DONG Wenje2 and YANG Bao3 (1.Department of Atmospheric Sciences, School of Physics, Peking University, Beijing 100871, china 2. Laboratory for Climate Studies, china meteorological administration, Beijing 100081, china 3. Institute of Cold and Arid Regions Environmental and Engineering, Chinese Academy of Sciences, Lanzhou 730000, china) [a] Department of Atmospheric Sciences School of Physics Peking University Beijing China [b] Laboratory for Climate Studies China Meterological Administration Beijing China [c] Institute of Cold and Arid Regions Environmental and Engineering Chinese Academy of Sciences Lanzhou China

Debating about the climate warming is reviewed. Discussions have focused on the validity of the temperature reconstruction for the last millennium made by Mann et al. Arguments against and for the reconstruction are introduced. Temperature reconstructions by other authors are examined, including the one carried out by Wang et al. in 1996. It is concluded that: (1) Ability of reproducing temperature variability of time scale less than 10 a is limited, so no sufficient evidence proves that the 1990s was the warmest decade, and 1998 was the warmest year over the last millennium. (2) All of the temperature reconstructions by different authors demonstrate the occurrence of the MWP (Medieval Warm Period) and LIA (Little Ice Age) in low frequency band of temperature variations, though the peak in the MWP and trough in LIA varies from one reconstruction to the others. Therefore, terms of MWP and LIA can be used in studies of climate change. (3) The warming from 1975.to 2000 was significant, but we do not know if it was the strongest for the last millennium, which needs to be proved by more evidence.

关键词： climate warming MWP LIA the 20th century.

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