OSTIA数据在中国近海业务化环流模型中的同化应用

The prediction of sea surface temperature(SST) is an essential task for an operational ocean circulation model. A sea surface heat flux, an initial temperature field, and boundary conditions directly affect the accuracy of a SST simulation. Here two quick and convenient data assimilation methods are employed to improve the SST simulation in the domain of the Bohai Sea, the Yellow Sea and the East China Sea(BYECS). One is based on a surface net heat flux correction, named as Qcorrection(QC), which nudges the flux correction to the model equation; the other is ensemble optimal interpolation(En OI), which optimizes the model initial field. Based on such two methods, the SST data obtained from the operational SST and sea ice analysis(OSTIA) system are assimilated into an operational circulation model for the coastal seas of China. The results of the simulated SST based on four experiments, in 2011, have been analyzed. By comparing with the OSTIA SST, the domain averaged root mean square error(RMSE) of the four experiments is 1.74, 1.16, 1.30 and 0.91°C, respectively; the improvements of assimilation experiments Exps 2, 3 and 4 are about 33.3%, 25.3%, and 47.7%, respectively.Although both two methods are effective in assimilating the SST, the En OI shows more advantages than the QC,and the best result is achieved when the two methods are combined. Comparing with the observational data from coastal buoy stations, show that assimilating the high-resolution satellite SST products can effectively improve the SST prediction skill in coastal regions.     

Dynamics of settling particulate matter during typhoon Muifa in Heini Bay,China

Settling particulate matter(SPM) is widely used to describe the sedimentary environment.We have investigated here the SPM collected with a time-series sediment trap in the Heini Bay,Weihai,Shandong Peninsula,China,during the super typhoon Muifa(August 2011,maximum wind speed 55 m/s).Meteorological and hydrological parameters were measured for 18 days.By analyzing the particle flux,grain size,and loss-on-ignition(organic matter content) of SPM we found dramatic changes in these parameters,induced by typhoon Muifa for about 6 days.With the arrival of typhoon,the daily SPM fluxes increased sharply to the maximum at 76.4 g/(m~2·d) on the first day and this increase is about 9 times of the normal value,and after 6 days the SPM decreased to the normal value gradually.Other parameters,such as grain size of SPM and organic matter also experienced similar changes.Using these SPM parameters,we divided the settling progress by cluster analysis into three phases:strong(for 3 days),weak(for 3 days),and zero typhoon impact.     

РГН-1型定向辐射仪

PΓH-1型定向辐射仪用于在有高底数照射下测量某一方向的γ辐射强度,或用于测定辐射源的位置。该仪器适用于坑道或矿场中作γ辐射取样。仪器可测量局部矿块的γ辐射,是一种直讀式取样辐射仪。当用已知品位的矿体模型校正求出换算系数后,可由仪器讀数直接换算出被作辐射取样的矿块铀的视品位。(即假定矿块具有大于饱和层的厚度和铀、镭、氢平衡的情况下的品位)     

局部非均匀性介质中PSV波传播：混合公式及其应用

把所谓的“数值”和“解析”法综合在一起的混合法，是计算局部非均匀区域合成地震图的一种成功的工具。数值法和解析法分别应用于介质中有效使用的那一部分。本文讨论了应用于非均匀区域邻域的有限差分算法和应用于非均匀区之外的ＰＳＶ波动方程的频率－波数滤波法的联合问题，该方法可以替代格林函数作为波场延拓方法。本文所述混合法中，可考虑吸收，对于不同的一，二阶间断模型试算，与反射率法比较表明，该混合法非常成功。作者     

也谈大风廓线的分布

风压是建筑物承受的主要自然荷载。由于各高度上的风压值是根据地面风速资料推算的,而风随高度变化的实测资料较少,所以究竟用什么方法来推算才比较符合实际,还有一些不同的看法。下面谈谈我们对这方面一些问题的看法。