From ERA5 to ERA6

Speaker: Dr. Hans Hersbach, Principal Scientist & Reanalysis Team Leader, European Centre for Medium-Range Weather Forecasts (ECMWF)

At ECMWF, reanalysis makes a key contribution to the Copernicus Services (C3S and CAMS), which ECMWF implements on behalf of the European Commission. ERA5 is ECMWF’s most recent global atmospheric reanalysis, providing hourly snapshots of the Earth’s atmosphere, land surface and ocean waves from 1940 onwards, with daily updates available five days behind real time. It is used by hundreds of thousands of users across a wide range of sectors, from scientific research to commercial applications, and has become a major training dataset for data-driven weather prediction models. Production of its successor, ERA6, is now underway. ERA6 benefits from eight additional years of R&D at ECMWF, more and improved observations and forcings, and an increase in horizontal resolution from 31 km in ERA5 to 14 km for the atmosphere, land and ocean waves. The model component also includes a coupled ocean at 0.25-degree horizontal resolution, initialized from ORAS6. ERA6 furthermore addresses several known issues in ERA5, including improved treatment of systematic model errors in the stratosphere, with the aim of further improving the quality of climate trends in this region. In response to user demand, ERA6 will include a number of new products, including 3D ocean fields and selected key 2D ocean variables, as well as 3D clear-air turbulence, several new atmospheric surface parameters, and key parameters on height levels up to 500 metres above the surface. All fields will be available hourly, complemented by precomputed daily and monthly statistics. As with ERA5, ERA6 is produced in parallel 10-year streams. Streams from 1987 onwards are produced and made available first, while streams extending back to around 1950 will be produced later. This presentation will summarise ERA5, describe the main scientific and product developments in ERA6, show initial results, and outline the projected production timelines.

 

Dr. Hans Hersbach is a principal scientist who leads the Climate Reanalysis Team at the European Centre for Medium-Range Weather Forecasts (ECMWF), working in support of the Copernicus Climate Change Service (C3S).

With a career spanning over three decades in data assimilation and climate science, together with his team, Dr. Hersbach is recognized as the principal architect of ERA5, the world’s leading atmospheric reanalysis dataset. ERA5 provides researchers and policymakers worldwide with highly accurate, hourly reconstructions of the global climate from 1940 to the present. He currently leads the development of its next-generation successor, ERA6.

Key Expertise:

Climate Reanalysis & Data Assimilation

Predictability

Satellite and In-situ Data & Ocean Wave Modelling