检索结果-南通市图书馆

Evaluation on monthly sea surface wind speed of four reanalysis data sets over the China seas after 1988

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2020年第1期39卷 83-90页

作者： Guosong Wang Xidong Wang Hui Wang Min Hou Yan Li Wenjing Fan Yulong Liu College of Oceanography Hohai University Nanjing 210098China National Marine data and Information Service Tianjin 300171China Tianjin Binhai New Area Meteorology Administration Tianjin 300457China

This study investigates the long-term changes of monthly sea surface wind speeds over the China seas from 1988 to 2015. The 10-meter wind speeds products from four major global reanalysis datasets with high resolution are used: Cross-Calibrated Multi-Platform data set(CCMP), NCEP climate forecast system reanalysis data set(CFSR),ERA-interim reanalysis data set(ERA-int) and Japanese 55-year reanalysis data set(JRA55). The monthly sea surface wind speeds of four major reanalysis data sets have been investigated through comparisons with the longterm and homogeneous observation wind speeds data recorded at ten stations. The results reveal that(1) the wind speeds bias of CCMP, CFSR, ERA-int and JRA55 are 0.91 m/s, 1.22 m/s, 0.62 m/s and 0.22 m/s, *** wind speeds RMSE of CCMP, CFSR, ERA-int and JRA55 are 1.38 m/s, 1.59 m/s, 1.01 m/s and 0.96 m/s,respectively;(2) JRA55 and ERA-int provides a realistic representation of monthly wind speeds, while CCMP and CFSR tend to overestimate observed wind speeds. And all the four data sets tend to underestimate observed wind speeds in Bohai Sea and Yellow Sea;(3) Comparing the annual wind speeds trends between observation and the four data sets at ten stations for 1988-1997, 1988–2007 and 1988–2015, the result show that ERA-int is superior to represent homogeneity monthly wind speeds over the China seaes.

关键词： monthly sea surface wind speeds China Sea reanalysis data inhomogeneity evaluation trend analysis

Applicability evaluation of ERA5 wind and wave reanalysis data in the South China Sea

在线全文

学校读者我要写书评

暂无评论

Journal of Oceanology and Limnology 2023年第2期41卷 495-517页

作者： Rongwei ZHAI Caijing HUANG Wei YANG Ling TANG Wenjing ZHANG South China Sea Information Center of State Oceanic Administration Guangzhou 510310China Key Laboratory of Marine Environmental Survey Technology and Application Ministry of Natural ResourcesGuangzhou 510300China South China Sea Marine Surveying and Technology Center State Ocean AdministrationGuangzhou 510300China

Wind and wave data are essential in climatological and engineering design *** this study,data from 15 buoys located throughout the South China Sea(SCS)were used to evaluate the ERA5 wind and wave *** assessment are beneficial for gaining insight into the reliability of the ERA5 data in the *** bias range between the ERA5 and observed wind-speed data was-0.78-0.99 m/*** result indicates that,while the ERA5 wind-speed data underestimation was dominate,the overestimation of such data existed as ***,the ERA5 data underestimated annual maximum wind-speed by up to 38%,with a correlation coefficient>*** bias between the ERA5 and observed significant wave height(SWH)data varied from-0.24 to 0.28 *** the ERA5 data showed positive SWH bias,which implied a general underestimation at all locations,except those in the Beibu Gulf and centralwestern SCS,where overestimation was *** extreme conditions,annual maximum SWH in the ERA5 data was underestimated by up to 30%.The correlation coefficients between the ERA5 and observed SWH data at all locations were greater than 0.92,except in the central-western SCS(0.84).The bias between the ERA5 and observed mean wave period(MWP)data varied from-0.74 to 0.57 *** ERA5 data showed negative MWP biases implying a general overestimation at all locations,except for B1(the Beibu Gulf)and B7(the northeastern SCS),where underestimation was *** correlation coefficient between the ERA5 and observed MWP data in the Beibu Gulf was the smallest(0.56),and those of other locations fluctuated within a narrow range from 0.82 to *** intercomparison indicates that during the analyzed time-span,the ERA5 data generally underestimated wind-speed and SWH,but overestimated *** non-extreme conditions,the ERA5 wind-speed and SWH data can be used with confidence in most regions of the SCS,except in the central-western SCS.

关键词： ERA 5 reanalysis data wind speed significant wave height mean wave period South China Sea(SCS)

Validation of ECMWF and NCEP–NCAR reanalysis data in Antarctica

在线全文

学校读者我要写书评

暂无评论

Advances in Atmospheric Sciences 2010年第5期27卷 1151-1168页

作者：于乐江张占海周明煜 Shiyuan ZHONG Donald LENSCHOW Hsiaoming HSU 吴辉碇孙波 Polar Research Institute of China Shanghai 200136 Department of Geography Michigan State University East Lansing MI 48824-111 USA National Center for Atmospheric Research Boulder CO 80307 USA National Marine Environmental Forecast Center Beijing 100081

The European Center for Medium-Range Weather Forecast （ECMWF） Re-Analysis （ERA-40） and the National Centers for Environmental Prediction-National Center for Atmospheric Research （NCEP-NCAR） ECMWF （ERA-40） and NCEP–NCAR reanalysis data were compared with Antarctic station observations, including surface-layer and upper-layer atmospheric observations, on intraseasonal and interannual timescales. At the interannual timescale, atmospheric pressure at different height levels in the ERA-40 data are in better agreement with observed pressure than that in the NCEP–NCAR reanalysis data. ERA-40 reanalysis also outperforms NCEP–NCAR reanalysis in atmospheric temperature, except in the surface layer where the biases are somewhat larger. The wind velocity fields in both datasets do not agree well with surface-and upper-layer atmospheric observations. At intraseasonal timescales, both datasets capture the observed intraseasonal variability in pressure and temperature during austral winter.

关键词： reanalysis data interannual variability intraseasonal variability surface layer upper layer Antarctica

Assessing the Quality of Regional Ocean reanalysis data from ENSO Signals

在线全文

学校读者我要写书评

暂无评论

Atmospheric and Oceanic Science Letters 2012年第1期5卷 55-61页

作者： WANG Lu ZHOU Tian-Jun State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics （LASG） Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate University of the Chinese Academy of Sciences Beijing 100029 China

The quality of regional ocean reanalysis data for ＂the joining area of Asia and the Indian-Pacific Ocean （AIPO）＂ has been assessed from the perspective of ENSO-related ocean signals. The results derived from the AIPO reanalysis, including SST, sea surface height （SSH）, and subsurface ocean temperature and currents, are compared with those of Hadley Center Sea Ice and Sea Surface Temperature （HadlSST） data set and Simple Ocean data Assimilation （SODA） reanalysis data. Both the spatial pattern and the characteristics of evolution of the ENSO-related ocean temperature anomalies are well reproduced by the AIPO reanalysis data. The physical processes proposed to explain the life cycle of ENSO, including the delayed oscillator mechanism, recharge-discharge mechanism, and the zonal advection feedback, are reasonably represented in this dataset. However, the westward Rossby wave signal in 1992 is not obvious in the AIPO data, and the magnitude of the heat content anomalies is different from that of the SODA data. The reason for the discrepancies may lie in the different mod- els and methods for data assimilation and differences in wind stress forcing. The results demonstrate the high reliability of the AIPO reanalysis data in describing ENSO signals, implying its potential application value in ENSO- related studies.

关键词： reanalysis data ENSO ocean assimilation AIPO data

Validation of the Relationship between Precipitable Water and Surface Vapor Pressure by Means of reanalysis data

在线全文

学校读者我要写书评

暂无评论

Meteorological and Environmental Research 2010年第5期1卷 1-6,27页

作者：张凯静戴新刚兰州大学大气科学学院甘肃兰州730000 中国科学院大气物理研究所东亚气候-环境重点实验室北京100029

By means of ERA-40, JRA-25, NCEP/NCAR and NCEP/DOE reanalysis data, empirical relations between precipitable water and surface vapor pressure in spatial and temporal scale were calculated. The reliabilities of precipitable water from reanalysis data were validated based on comparing different W-e empirical relations of various reanalysis data, in order to provide basis and reference for reasonable application. The results showed that W-e empirical relation of ERA-40 was closest to that of sounding data in China, and precipitable water from ERA-40 was the most credible. The worldwide comparison among W-e empirical relations of four reanalysis data showed that there was little difference in annual mean W-e empirical relations in the middle latitudes and great differences in low and high latitudes. Seasonal mean W-e empirical relations in the middle latitudes of the northern Hemisphere had little difference in spring, autumn and winter, but great difference in summer. Therefore, the reliabilities of precipitable water from reanalysis data in spring, autumn and winter in the middle latitudes of the northern hemisphere were higher than other areas and seasons. W-e empirical relations of NCEP/NCAR and NCEP/DOE had good stability in different years, while there was poor stability in ERA-40 and JRA-25.

关键词： reanalysis data Surface vapor pressure Precipitable water Statistical relationship China

DIFFERENCES OF SOUTH CHINA SEA SUMMER MONSOON DERIVED BY NCEP AND ECMWF reanalysis data

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Tropical Meteorology 2006年第2期12卷 197-200页

作者：郑彬谷德军李春晖 Key Open Laboratory for Tropical Monsoon Guangzhou Institute of Tropical and Marine MeteorologyCMA

Due to long-term time series and many elements, reanalysis data of National Centers for Environmental Prediction （NCEP） and European Center for MediumRange Weather Forecasts （ECMWF） are widely used in present climate studies. Even so, there are discrepancies between NCEP and ECMWF reanalysis. Some climate fields may be better reproduced by NCEP than by ECMWF. On the other hand, ECMWF may describe some climate characteristics more realistically than NCEP. Xu et *** out that NCEP data are of uncertainty when used for studying long-term trends of climate change. By comparing temperatures and pressures from NCEP and observation, it can be seen that NCEP data show higher reliability in the east and lower-latitudes of China than in its west and higher latitudes, NCEP temperature is of more reality than pressure and NCEP data after 1979 are closer to the observations than before. Yang et *** revealed some serious problems of NCEP data in the north of subtropical Asia. Regional differences of NCEP data in representation are also explored by other studiest. As for seasonal variability, NCEP simulates relatively real conditions of Chinese summer and annual mean but winter data are relatively bad, as in comparisons of NCEP data wity China surface station observations by Zhao et ***, Trenberth and Stepaniak showed that ECMWF data had better energy budgets than NCEP data for pure pressure coordinates are adopted by ECMWF. Renfrew et al. compared NCF, P data to ECMWF data in terms of surface fluxes and the results indicate that the time series of surface sensible and latent heating fluxes from ECMWF are 13% and 10% larger than the observations and those from NCEP would be 51% and 27% larger than the observations, respectively. So, Renfrew et al. suggested that it be more appropriate to drive ocean models by ECMWF data. Based on comparisons of multiple elements by some scientists, it seems that ECMWF data are better than NCEP data on global, hemispheric and regi

关键词： NCEP ECMWF reanalysis data South China Sea summer monsoon

Uncertainties of ENSO-related Regional Hadley Circulation Anomalies within Eight reanalysis datasets

在线全文

学校读者我要写书评

暂无评论

Advances in Atmospheric Sciences 2024年第1期41卷 115-140页

作者： Yadi LI Xichen LI Juan FENG Yi ZHOU Wenzhu WANG Yurong HOU International Center for Climate and Environment Sciences(ICCES) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 101408China College of Global Change and Earth System Science(GCESS) Beijing Normal UniversityBeijing 100875China

El Nino-Southern Oscillation(ENSO),the leading mode of global interannual variability,usually intensifies the Hadley Circulation(HC),and meanwhile constrains its meridional extension,leading to an equatorward movement of the jet *** studies have investigated the response of HC to ENSO events using different reanalysis datasets and evaluated their capability in capturing the main features of ENSO-associated HC ***,these studies mainly focused on the global HC,represented by a zonal-mean mass stream function(MSF).Comparatively fewer studies have evaluated HC responses from a regional perspective,partly due to the prerequisite of the Stokes MSF,which prevents us from integrating a regional *** this study,we adopt a recently developed technique to construct the three-dimensional structure of HC and evaluate the capability of eight state-of-the-art reanalyses in reproducing the regional HC response to ENSO *** show that all eight reanalyses reproduce the spatial structure of HC responses well,with an intensified HC around the central-eastern Pacific but weakened circulations around the Indo-Pacific warm pool and tropical *** spatial correlation coefficient of the three-dimensional HC anomalies among the different datasets is always larger than ***,these datasets may not capture the amplitudes of the HC responses *** uncertainty is especially large for ENSO-associated equatorially asymmetric HC anomalies,with the maximum amplitude in Climate Forecast System reanalysis(CFSR)being about 2.7 times the minimum value in the Twentieth Century reanalysis(20CR).One should be careful when using reanalysis data to evaluate the intensity of ENSO-associated HC anomalies.

关键词： regional Hadley circulation ENSO atmosphere-ocean interaction reanalysis data

A Comparison of Atmospheric Temperature over China between Radiosonde Observations and Multiple reanalysis datasets

在线全文

学校读者我要写书评

暂无评论

Journal of Meteorological Research 2016年第2期30卷 242-257页

作者：郭艳君张思齐颜京辉陈哲阮新 National Climate Center China Meteorological Administration National Meteorological Information Center China Meteorological Administration

The quality controlled（RAW） and homogenized（ADJ） radiosonde temperatures within 850-30 hPa collected at 118 stations in China are compared,on a monthly mean basis,with the temperatures extracted from 8 reanalysis datasets（REA） including NCEP-1,NCEP-2,ERA-40（ECMWF 45-yr reanalysis）,ERAInterim,JRA-55（Japanese 55-yr reanalysis）,20CR（20th Century reanalysis）,MERRA（Modern Era Retrospective-Analysis）,and CFSR（Climate Forecast System reanalysis）.Average differences,correlations,standard deviations,and linear trends among RAW,ADJ,and REA for the period 1981-2010 are *** results reveal significant inhomogeneity in the time series of RAW radiosonde temperature in China;an overall negative adjustment was thus employed to obtain the ADJ temperatures,and the effect of the negative adjustment is the most significant within 200-100 *** a homogenization process has removed the system errors in RAW,possibly caused by radiosonde instrument changes and observation system ***,the correlation is higher between ADJ and REA than that between RAW and *** mean difference between ADJ and REA is about 1℃ during 1981-2010,while REA are mostly cooler in the troposphere and warmer in the stratosphere than ADJ;nonetheless,they have a significant high and positive correlation and their annual variability is notably ***,the linear trends in REA and ADJ both demonstrate warming in the lower-mid troposphere and cooling in the mid stratosphere,with large uncertainties found in the upper troposphere and lower *** general,ERA-Interim,JRA-55,and MERRA are more consistent with ADJ than other reanalysis datasets.

关键词： radiosonde air temperature reanalysis data China raw versus homogenized data

Comparison of sensible and latent heat fluxes during the transition season over the western Tibetan Plateau from reanalysis datasets

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2009年第6期19卷 719-726页

作者： Yang Cui, Chenghai Wang Disaster Reduction Key Laboratory of Gansu Province, College of Atmospheric Sciences, Lanzhou University, Lanzhou 730000, China Disaster Reduction Key Laboratory of Gansu Province College of Atmospheric Sciences Lanzhou University Lanzhou 730000 China

The sensible and latent heat fluxes during the transition season over the western Tibetan Plateau from the NCEP-1 (NCEP/NCAR reanalysis 1), AR-Ⅱ (NCEP-DOE reanalysis 2) and ERA40 reanalysis datasets were compared and analyzed. The results show that the phase change in soil moisture has a significant effect on the sensible and latent heat fluxes over the western Tibetan Plateau (TP) due to the freezing-thawing processes during the transition from the dry to the wet period. The uncertainties in the sensible and latent heat fluxes over the western TP are quite high in the reanalysis data, and depend largely on the success of the soil moisture simulations in the models. Improving the hydrological process simulations in the land-surface models in seasonally frozen ground and in the active frozen soil layer may be an effective way of enhancing the reliability of the surface heat fluxes from the reanalysis data over the Tibetan Plateau.

关键词： Western Tibetan Plateau Surface heat fluxes reanalysis data Transition season Freezing-thawing process