|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | A Deep Learning Method for Bias Correction of ECMWF 24–240 h Forecasts显示文摘Correcting the forecast bias of numerical weather prediction models is important for severe weather warnings.The refined grid forecast requires direct correction on gridded forecast products,as opposed to correcting forecast data only at individual weather stations.In this study,a deep learning method called CU-net is proposed to correct the gridded forecasts of four weather variables from the European Centre for Medium-Range Weather Forecast Integrated Forecasting System global model(ECMWF-IFS): 2-m temperature,2-m relative humidity,10-m wind speed,and 10-m wind direction,with a forecast lead time of 24 h to 240 h in North China.First,the forecast correction problem is transformed into an image-toimage translation problem in deep learning under the CU-net architecture,which is based on convolutional neural networks.Second,the ECMWF-IFS forecasts and ECMWF reanalysis data(ERA5) from 2005 to 2018 are used as training,validation,and testing datasets.The predictors and labels(ground truth) of the model are created using the ECMWF-IFS and ERA5,respectively.Finally,the correction performance of CU-net is compared with a conventional method,anomaly numerical correction with observations(ANO).Results show that forecasts from CU-net have lower root mean square error,bias,mean absolute error,and higher correlation coefficient than those from ANO for all forecast lead times from 24 h to 240 h.CU-net improves upon the ECMWF-IFS forecast for all four weather variables in terms of the above evaluation metrics,whereas ANO improves upon ECMWF-IFS performance only for 2-m temperature and relative humidity.For the correction of the 10-m wind direction forecast,which is often difficult to achieve,CU-net also improves the correction performance. | Lei HAN Mingxuan CHEN Kangkai CHEN Haonan CHEN Yanbiao ZHANG Bing LU Linye SONG Rui QIN | 2021 | Advances in Atmospheric Sciences2021，38，9： | 15 |
| 2 | Organic compositions of lacustrine source rocks in Jiyang super-depression and its implication to petroleum geology显示文摘The compositions of organic matter in four immature source rocks from Tertiary strata of Jiyang super-depression, the most typical continental rift subsidence basin in East China, have been stud- ied by different extracting methods with CHCl3, MAC and CS2/NMP, respectively. The results suggest that there are great differences among the chemical compositions of organic matter in the source rocks derived from different depositional environments. About 79% of all the organic matter exists by non- covalent bond in the Es4 source rocks which were deposited under the saline lacustrine, indicating that its organic matter is not the real kerogen, but mainly composed of soluble organic matter which is easy to generate hydrocarbon at lower temperature. This is why the immature oils were derived from Es4 source rocks in Dongying depression. In contrast, around 60% of organic matter exists by covalent bond in Es3 source rocks which were deposited under the deep brackish-fresh lacustrine, showing that Es3 source rocks are mainly composed of kerogen producing mature hydrocarbon at higher temperature. The thermal simulation experiments, upon the remaining solid source rocks which were sequentially extracted by the three solvents, have been carried out. The chloroform extracts from the simulation product have been compared with the other three solvent extracts gained at room temperature. It is obvious that re-markable odd/even predominance (OEP) is mainly the characteristic of soluble organic matter; phytane mostly exists in the soluble organic matter by means of non-covalent bonds and characteristics of soluble organic matter are similar to these in immature oils produced in Jiyang super-depression. | ZHANG Linye SONG Yitao WANG Guangli HUANG Difan | 2006 | Chinese Science Bulletin2006，51，5： | 4 |
| 3 | A Timescale Decomposed Threshold Regression Downscaling Approach to Forecasting South China Early Summer Rainfall显示文摘A timescale decomposed threshold regression(TSDTR) downscaling approach to forecasting South China early summer rainfall(SCESR) is described by using long-term observed station rainfall data and NOAA ERSST data. It makes use of two distinct regression downscaling models corresponding to the interannual and interdecadal rainfall variability of SCESR.The two models are developed based on the partial least squares(PLS) regression technique, linking SCESR to SST modes in preceding months on both interannual and interdecadal timescales. Specifically, using the datasets in the calibration period 1915–84, the variability of SCESR and SST are decomposed into interannual and interdecadal components. On the interannual timescale, a threshold PLS regression model is fitted to interannual components of SCESR and March SST patterns by taking account of the modulation of negative and positive phases of the Pacific Decadal Oscillation(PDO). On the interdecadal timescale, a standard PLS regression model is fitted to the relationship between SCESR and preceding November SST patterns. The total rainfall prediction is obtained by the sum of the outputs from both the interannual and interdecadal models. Results show that the TSDTR downscaling approach achieves reasonable skill in predicting the observed rainfall in the validation period 1985–2006, compared to other simpler approaches. This study suggests that the TSDTR approach,considering different interannual SCESR-SST relationships under the modulation of PDO phases, as well as the interdecadal variability of SCESR associated with SST patterns, may provide a new perspective to improve climate predictions. | Linye SONG Wansuo DUAN Yun LI Jiangyu MAO | 2016 | Advances in Atmospheric Sciences2016，33，9： | 2 |
| 4 | Distribution of aromatic bio-markers in pyrolysates of co-ccolithophore显示文摘Analyses of the original and pyrolytic products of coccolithophore at various temperatures suggest that the contribution of coccolithophore to the formation of large immature oil reservoirs should attract keen interest. Through biochemical processes algae can change inorganic sulphur into organic sulphur, which could be one of the most important precursors of organic sulphur compounds in oil and source rocks. When Methylphenanthrene Index (MPI) and Methylphenanthrene Ratio (MPR) indices were used to evaluate the evolution degree of source rocks and oil maturity, other maturity indices must be used together for correction. In low maturity, the relative abundances of diben-zothiophene (DBT), fluorine (F) and dibenzofuran (DBF) can be used to identify the oxidation-reduction environments. | ZHOU Wen WU Qingyu WANG Ruiyong SONG Yitao ZHANG Linye LIU Zhili | 2001 | Chinese Science Bulletin2001，46，3： | 2 |
| 5 | Impact of the Winter North Pacific Oscillation on the Surface Air Temperature over Eurasia and North America: Sensitivity to the Index Definition显示文摘This study analyzes the impact of the winter North Pacific Oscillation(NPO) on the surface air temperature(SAT)variations over Eurasia and North America based on six different NPO indices. Results show that the influences of the winter NPO on the SAT over Eurasia and North America are sensitive to the definition of the NPO index. The impact of the winter NPO on the SAT variations over Eurasia(North America) is significant(insignificant) when the anticyclonic anomaly associated with the NPO index over the North Pacific midlatitudes shifts westward and pronounced northerly wind anomalies appear around Lake Baikal. By contrast, the impact of the winter NPO on the SAT variations over Eurasia(North America)is insignificant(significant) when the anticyclonic anomaly over the North Pacific related to the NPO index shifts eastward and the associated northerly wind anomalies to its eastern flank extend to North America. The present study suggests that the NPO definition should be taken into account when analyzing the impact of the winter NPO on Eurasian and North American SAT variations. | Shangfeng CHEN Linye SONG | 2018 | Advances in Atmospheric Sciences2018，35，6： | 1 |
| 6 | Interdecadal Modulation of AMO on the Winter North Pacific Oscillation-Following Winter ENSO Relationship显示文摘It is known that the wintertime North Pacific Oscillation (NPO) is an important extratropical forcing for the occurrence of an El Ni-o-Southern Oscillation (ENSO) event in the subsequent winter via the “seasonal footprinting mechanism ”(SFM). This study reveals that the Atlantic Multidecadal Oscillation (AMO) can notably modulate the relationship between the winter NPO and the following winter ENSO. During the negative AMO phase, the winter NPO has significant impacts on the following winter ENSO via the SFM. In contrast, the influence of the winter NPO on ENSO is not robust at all during the positive AMO phase. Winter NPO-generated westerly wind anomalies over the equatorial western Pacific during the following spring are much stronger during negative than positive AMO phases. It is suggested that the AMO impacts the winter NPO-induced equatorial westerly winds over the western Pacific via modulating the precipitation climatology over the tropical central Pacific and via modulating the connection of the winter NPO with spring sea surface temperature in the tropical North Atlantic. | Shangfeng CHEN Linye SONG Wen CHEN | 2019 | Advances in Atmospheric Sciences2019，36，12： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员