The two Copernicus Earth observation services run by ECMWF will set out how they can support evidence-based decision-making as world leaders meet in Paris to agree a new climate deal.
The 21st session of the Conference of the Parties (COP21) of the United Nations Framework Convention on Climate Change (UNFCCC) takes place in Paris from 30 November to 11 December 2015.
The EU-funded Copernicus Climate Change and Atmosphere Monitoring Services (C3S and CAMS) will hold a joint COP21 side event on 10 December to present the powerful climate and atmosphere information tools they can provide.
Key speakers are the Heads of C3S and CAMS, Jean-Noël Thépaut and Vincent-Henri Peuch, and EUMETSAT Chief Scientist Ken Holmlund.
ECMWF's delegation, led by Director of Copernicus Services Juan Garces de Marcilla, will also run a Copernicus stand in the conference site's blue zone. On 1 December Vincent-Henri Peuch will take part in a side event on the impact of CO2 reduction on pollution and public health.
"It is only fitting that the Copernicus Services are going to COP21. They are part of the solution, helping others to take action through accurate, exhaustive and totally open data,” said Jean-Noël Thépaut.
CAMS has been operational since the summer. Its products, which are freely available on the CAMS website, include near real-time analyses and forecasts of global atmospheric composition. They can be used to track the presence of climate change drivers in the atmosphere.
C3S is still being developed but is already publishing monthly climate updates on its website. The most recent figures for average global near-surface air temperatures show that the twelve months up to and including October 2015 were the warmest on record compared to the 1981 to 2010 average.
Twelve-month running-mean anomalies in global-mean near-surface air temperature relative to 1981–2010, based on the ERA-Interim reanalysis. The darker-coloured bars are the averages for each of the calendar years from 1979 to 2014.
The science behind the data
The data used by C3S are based on observations from weather stations, aircraft, satellites and other sources. But that on its own would not be enough as observations are patchy and not always reliable.
The observations must be combined with a modern forecast model, using data assimilation techniques originally developed for numerical weather prediction (NWP).
C3S uses ECMWF’s global forecast model to do this. The resulting reanalysis dataset, called ERA-Interim, provides a comprehensive, consistent and up-to-date record of the global climate in the satellite era since 1979. Inevitably, the data also carry a degree of uncertainty.
When fully operational, C3S will use a new dataset, called ERA5, based on ECMWF’s latest forecast model and using reprocessed satellite datasets.
ERA5 also covers the satellite era and will incorporate the results of climate reanalysis research carried out at ECMWF. It will produce an ensemble of reanalyses, taking into account inevitable uncertainties in the observational record and the forecast model. This will provide an indication of the confidence we can have in ERA5 data.
This ECMWF animation is based on ERA-20CM, a set of extended model runs covering the 20th century. It shows how global temperatures changed between 1900 and 2010 compared to the 20th-century average.
Separately, ECMWF has produced ERA-20CM, a climate model integration spanning the entire 20th century, and ERA-20C, an atmospheric reanalysis covering the same period.
It is now producing a new 20th century coupled reanalysis, called CERA-20C, in which ocean and atmospheric observations are assimilated simultaneously into a coupled atmosphere–ocean model. This work, which aims to produce a comprehensive estimate of the evolution of the Earth system, is part of the ERA-CLIM2 project funded by the European Commission under the 7th Framework Programme.
20th-century reanalyses provide a record of low-frequency climate variability and change using a consistent set of non-satellite observations. They can serve to provide a longer-term perspective on more recent temperature anomalies.