ERA5 hourly data on single levels from 1940 to present

ERA5 is the fifth generation ECMWF reanalysis for the global climate and weather for the past 8 decades.
Data is available from 1940 onwards.
ERA5 replaces the ERA-Interim reanalysis.
Reanalysis combines model data with observations from across the world into a globally complete and consistent dataset using the laws of physics. This principle, called data assimilation, is based on the method used by numerical weather prediction centres, where every so many hours (12 hours at ECMWF) a previous forecast is combined with newly available observations in an optimal way to produce a new best estimate of the state of the atmosphere, called analysis, from which an updated, improved forecast is issued. Reanalysis works in the same way, but at reduced resolution to allow for the provision of a dataset spanning back several decades. Reanalysis does not have the constraint of issuing timely forecasts, so there is more time to collect observations, and when going further back in time, to allow for the ingestion of improved versions of the original observations, which all benefit the quality of the reanalysis product.
ERA5 provides hourly estimates for a large number of atmospheric, ocean-wave and land-surface quantities.
An uncertainty estimate is sampled by an underlying 10-member ensemble
at three-hourly intervals. Ensemble mean and spread have been pre-computed for convenience.
Such uncertainty estimates are closely related to the information content of the available observing system which
has evolved considerably over time. They also indicate flow-dependent sensitive areas.
To facilitate many climate applications, monthly-mean averages have been pre-calculated too,
though monthly means are not available for the ensemble mean and spread.
ERA5 is updated daily with a latency of about 5 days. In case that serious flaws are detected in this early release (called ERA5T), this data could be different from the final release 2 to 3 months later. In case that this occurs users are notified.
The data set presented here is a regridded subset of the full ERA5 data set on native resolution.
It is online on spinning disk, which should ensure fast and easy access.
It should satisfy the requirements for most common applications.
An overview of all ERA5 datasets can be found in this article.
Information on access to ERA5 data on native resolution is provided in these guidelines.
Data has been regridded to a regular lat-lon grid of 0.25 degrees for the reanalysis and 0.5 degrees for
the uncertainty estimate (0.5 and 1 degree respectively for ocean waves).
There are four main sub sets: hourly and monthly products, both on pressure levels (upper air fields) and single levels (atmospheric, ocean-wave and land surface quantities).
The present entry is "ERA5 hourly data on single levels from 1940 to present".

ERA5系欧洲中期天气预报中心（ECMWF）针对过去八十年全球气候与天气的第五代再分析数据集。该数据集自1940年起提供数据。ERA5取代了前一代的ERA-Interim再分析。再分析技术通过结合模型数据与全球范围内的观测数据，依据物理定律构建了一个全球范围内完整且一致的数据集。此方法，即数据同化，借鉴了数值天气预报中心的方法，即每隔数小时（在ECMWF为12小时）将前一次预测与最新观测数据以最优方式相结合，生成新的最佳大气状态估计，称为分析，进而据此发布更新后的改进预测。再分析的工作原理与此相似，但分辨率降低，以便提供涵盖数十年时间跨度的数据集。由于再分析无需及时发布预测，因此有更多时间收集观测数据，并在追溯历史时，允许纳入改进后的原始观测版本，从而全面提升再分析产品的质量。ERA5提供了大量大气、海洋波浪和地表数量小时的估计值。通过底层10成员集合，以每三小时一次的频率采样不确定性估计，并预先计算集合平均和分散以方便使用。此类不确定性估计与可用观测系统的信息含量密切相关，该系统随着时间的推移发生了显著演变。它们还指示了与流动相关的敏感区域。为了便利众多气候应用，还预先计算了月平均值，尽管集合平均和分散的月平均值不可用。ERA5每日更新，滞后约5天。如果在此早期发布（称为ERA5T）中检测到严重缺陷，则这些数据可能与两个月后发布的最终版本2至3有所不同。在此情况下，用户将收到通知。本处展示的数据集是完整ERA5数据集在原生分辨率上的重网格子集，存储于在线旋转磁盘上，以确保快速便捷的访问。它应满足大多数常见应用的需求。所有ERA5数据集的概述可在此篇文章中找到。有关访问原生分辨率ERA5数据的指南提供在这些指导方针中。数据已被重网格化到0.25度（用于再分析）和0.5度（用于不确定性估计，海洋波浪分别为0.5度和1度）的规则经纬网格。主要分为四个子集：小时和月度产品，包括压力层（高空场）和单层（大气、海洋波浪和地表数量）。当前条目为“1940年至现在的ERA5单层小时数据”。

搜集汇总

背景与挑战

背景概述

ERA5是ECMWF提供的全球气候和天气再分析数据集，覆盖1940年至今，提供每小时的大气、海浪和地表变量估计值，并包含不确定性估计。数据通过数据同化技术结合模型和观测数据，确保全球一致性和完整性，适用于大多数常见应用。