NCEP FNL Operational Model Global Tropospheric Analyses, continuing from July 1999

These NCEP FNL (Final) Operational Global Analysis data are on 1-degree by 1-degree grids prepared operationally every six hours. This product is from the Global Data Assimilation System (GDAS), which continuously collects observational data from the Global Telecommunications System (GTS), and other sources, for many analyses. The FNLs are made with the same model which NCEP uses in the Global Forecast System (GFS), but the FNLs are prepared about an hour or so after the GFS is initialized. The FNLs are delayed so that more observational data can be used. The GFS is run earlier in support of time critical forecast needs, and uses the FNL from the previous 6 hour cycle as part of its initialization.The analyses are available on the surface, at 26 mandatory (and other pressure) levels from 1000 millibars to 10 millibars, in the surface boundary layer and at some sigma layers, the tropopause and a few others. Parameters include surface pressure, sea level pressure, geopotential height, temperature, sea surface temperature, soil values, ice cover, relative humidity, u- and v- winds, vertical motion, vorticity and ozone.The archive time series is continuously extended to a near-current date. It is not maintained in real-time.

本数据集为美国国家环境预报中心（NCEP）FNL（最终）业务化全球分析数据，采用1°×1°网格格式，每6小时生成一次。该产品源自全球数据同化系统（GDAS）——该系统持续从全球电信系统（GTS）及其他来源收集观测数据，用于多类分析运算。FNL数据采用与NCEP全球预报系统（GFS）一致的数值模式制作，但FNL数据的生成时间比GFS初始化完成时间滞后约1小时。设置该延迟是为了纳入更多观测数据。GFS会提前运行以满足时效紧迫的预报需求，其初始化过程会用上一个6小时循环周期生成的FNL数据。该分析数据覆盖地表、从1000毫巴至10毫巴的26个标准（及其他）等压面层、地表边界层、部分西格玛层、对流层顶及其他少数层级。包含的参数包括：地表气压、海平面气压、位势高度、气温、海表温度、土壤参数、冰盖覆盖率、相对湿度、u风分量、v风分量、垂直运动、涡度与臭氧。该数据集的存档时间序列会持续更新至接近当前日期，但并非以实时方式维护。

搜集汇总

背景与挑战

背景概述

该数据集是NCEP FNL（最终）全球对流层分析数据，从1999年7月持续至今，提供每6小时一次的1度x1度网格全球气象分析。它包含温度、湿度、风速、气压、土壤湿度等多种气象变量，总数据量约884.11 GB，适用于气候研究、天气预报等应用。