NOAA NCEP Optimum Interpolation Sea Surface Temperature Analysis

The NOAA National Center for Environmental Prediction (NCEP) optimum interpolation (OI) sea surface temperature (SST) analysis is produced weekly and monthly on a one-degree grid. The analysis uses in situ and satellite SSTs plus SSTs simulated by sea ice cover. Before the analysis is computed, the satellite data is adjusted for biases using the method of Reynolds (1988) and Reynolds and Marsico (1993). A description of the OI analysis can be found in Reynolds and Smith (1994). The bias correction improves the large scale accuracy of the OI. In November 2001, the OI fields were recomputed for late 1981 onward. The new version will be referred to as OI Version 2, and the most significant change is the improved simulation of SST from sea ice data following a technique developed at the UK Met Office. This change has reduced biases in the OI SST at higher latitudes. Also, the update and extension of COADS has provided us with improved ship data coverage through 1997, reducing the residual satellite biases in otherwise data sparse regions. For more details, see Reynolds, et al. (2002).

美国国家海洋和大气管理局（National Oceanic and Atmospheric Administration, NOAA）下属的国家环境预报中心（National Center for Environmental Prediction, NCEP）研发的最优插值（Optimum Interpolation, OI）海表温度（Sea Surface Temperature, SST）分析产品，以周度和月度为时间分辨率，生成于1度网格之上。该分析融合了原位观测海表温度、卫星反演海表温度，以及海冰覆盖模拟得到的海表温度。在完成分析场计算前，卫星数据会采用Reynolds（1988）与Reynolds、Marsico（1993）提出的方法进行偏差校正。有关OI分析方法的详细说明可参阅Reynolds与Smith（1994）的研究成果，偏差校正步骤可有效提升OI分析产品的大尺度精度。2001年11月，研究团队对1981年末至今的OI分析场进行了重新计算，新版本被命名为OI版本2，其最显著的改进在于采用英国气象局（UK Met Office）开发的技术，优化了基于海冰数据模拟海表温度的流程，该改进有效降低了高纬度区域OI海表温度产品的系统性偏差。此外，对公共海洋大气数据集（COADS）的更新与扩展，使研究团队获得了截至1997年的更完备的船舶观测数据覆盖范围，进而减少了原本数据稀缺区域内的卫星反演残差偏差。更多细节可参阅Reynolds等人（2002）的相关研究。