ECMWF Re-Analysis Project ERA-Interim

ECMWF Re-Analysis Project ERA-Interim

Over the past decade, reanalyses of multi-decadal series of past observations
have become an important and widely utilized resource for the study of
atmospheric and oceanic processes and predictability. ECMWF has in the past
produced three major reanalyses: FGGE, ERA-15 and ERA-40.
ECMWF is currently producing ERA-Interim, a new global reanalysis of the
data-rich period since 1989. The ERA-Interim system is based on a recent release
of the Integrated Forecasting System (IFS Cy31r2) containing many improvements
both in the forecasting model and analysis methodology. ERA-Interim reanalysis
is expected to catch up with operations in late 2008. The reanalysis will then
be continued in near-real time with the same system in order to support climate
monitoring.
ERA-Interim has progressed beyond the end of ERA-40. After completion of the
first four years it was decided to revise the configuration of the system and to
rerun the initial segment. Other shorter reruns for later periods have been
completed as needed for technical reasons. The ERA-Interim archive is more
extensive than that for ERA-40, e.g the number of pressure levels is increased
from ERA-40's 23 to 37 levels and additional cloud parameters are included.

在过去十年间，对多年代观测数据的再分析已成为研究大气和海洋过程及其可预测性的重要且广泛应用的资源。欧洲中期天气预报中心（ECMWF）先前已生产了三个主要再分析项目：FGGE、ERA-15 和 ERA-40。目前，ECMWF 正在生成ERA-Interim，这是自1989年以来针对数据丰富时期的新全球再分析。ERA-Interim系统基于最近发布的综合预报系统（IFS Cy31r2）的最新版本，该版本在预报模型和分析方法上均有诸多改进。预计ERA-Interim再分析将在2008年底达到现有操作水平。此后，该再分析将使用同一系统在近实时状态下继续进行，以支持气候监测。ERA-Interim已超越ERA-40的终点。在完成前四年之后，决定修订系统的配置并重新运行初始段。根据技术需求，已完成对后期时段的其他较短的重新运行。与ERA-40相比，ERA-Interim的存档更为丰富，例如，压力层数从ERA-40的23层增加到37层，并增加了额外的云参数。