The ERA5 global reanalysis

Autor(en)
Hans Hersbach, Bill Bell, Paul Berrisford, Shoji Hirahara, Andras Horanyi, Joaquın Munoz-Sabater, Julien Nicolas, Carola Peubey, Raluca Radu, Dinand Schepers, Adrian Simmons, Cornel Soci, Saleh Abdalla, Xavier Abellan, Gianpaolo Balsamo, Peter Bechtold, Gionata Biavati, Jean Bidlot, Massimo Bonavita, Giovanna De Chiara, Per Dahlgren, Dick Dee, Michail Diamantakis, Rossana Dragani, Johannes Flemming, Richard Forbes, Manuel Fuentes, Alan Geer, Leopold Haimberger, Sean Healy, Robin J. Hogan, Elias Holm, Marta Janiskova, Sarah Keeley, Patrick Laloyaux, Philippe Lopez, Gabor Radnoti, Patricia de Rosnay, Iryna Rozum, Freja Vamborg, Sebastian Villaume, Jean-Noel Thepaut
Abstrakt

Within the Copernicus Climate Change Service (C3S), ECMWF is producing the ERA5 reanalysis which, once completed, will embody a detailed record of the global atmosphere, land surface and ocean waves from 1950 onwards. This new reanalysis replaces the ERA‐Interim reanalysis (spanning 1979 onwards) which was started in 2006. ERA5 is based on the Integrated Forecasting System (IFS) Cy41r2 which was operational in 2016. ERA5 thus benefits from a decade of developments in model physics, core dynamics and data assimilation. In addition to a significantly enhanced horizontal resolution of 31 km, compared to 80 km for ERA‐Interim, ERA5 has hourly output throughout, and an uncertainty estimate from an ensemble (3‐hourly at half the horizontal resolution). This paper describes the general set‐up of ERA5, as well as a basic evaluation of characteristics and performance, with a focus on the dataset from 1979 onwards which is currently publicly available. Re‐forecasts from ERA5 analyses show a gain of up to one day in skill with respect to ERA‐Interim. Comparison with radiosonde and PILOT data prior to assimilation shows an improved fit for temperature, wind and humidity in the troposphere, but not the stratosphere. A comparison with independent buoy data shows a much improved fit for ocean wave height. The uncertainty estimate reflects the evolution of the observing systems used in ERA5. The enhanced temporal and spatial resolution allows for a detailed evolution of weather systems. For precipitation, global‐mean correlation with monthly‐mean GPCP data is increased from 67% to 77%. In general, low‐frequency variability is found to be well represented and from 10 hPa downwards general patterns of anomalies in temperature match those from the ERA‐Interim, MERRA‐2 and JRA‐55 reanalyses.

Organisation(en)
Institut für Meteorologie und Geophysik
Externe Organisation(en)
European Centre for Medium-Range Weather Forecasts (ECMWF), Meteorological Research Institute - Japan Meteorological Agency, University of Reading, Norwegian Meteorological Institute
Journal
Quarterly Journal of the Royal Meteorological Society
Band
146
Seiten
1999-2049
Anzahl der Seiten
51
ISSN
0035-9009
DOI
https://doi.org/10.1002/qj.3803
Publikationsdatum
07-2020
Peer-reviewed
Ja
ÖFOS 2012
105204 Klimatologie, 105206 Meteorologie
Schlagwörter
ASJC Scopus Sachgebiete
Atmospheric Science
Sustainable Development Goals
SDG 13 – Maßnahmen zum Klimaschutz
Link zum Portal
https://ucris.univie.ac.at/portal/de/publications/the-era5-global-reanalysis(8cbb0d63-f4e4-4806-925c-90961f42d529).html