The Airborne Arctic Stratospheric Expedition (AASE) which was based in Stavanger, Norway during January and February, 1989, was designed to study the production and loss mechanisms of ozone in the north polar stratospheric environment, and the effect on ozone distribution of the Arctic polar vortex and of the cold temperatures associated with the formation of Polar Stratospheric Clouds (PSC). This dataset contains analyses of potential vorticity and pressure on constant potential temperature surfaces.

The Airborne Arctic Stratospheric Expedition (AASE) which was based in Stavanger, Norway during January and February, 1989, was designed to study the production and loss mechanisms of ozone in the north polar stratospheric environment, and the effect on ozone distribution of the Arctic polar vortex and of the cold temperatures associated with the formation of Polar Stratospheric Clouds (PSC). This dataset contains analyses of temperature, geopotential height, and horizontal wind components on constant pressure surfaces.

This dataset contains ERA5.1 surface level analysis parameter data for the period 2000-2006 from 10 member ensemble runs. ERA5.1 is the European Centre for Medium-Range Weather Forecasts (ECWMF) ERA5 reanalysis project re-run for 2000-2006 to improve upon the cold bias in the lower stratosphere seen in ERA5 (see technical memorandum 859 in the linked documentation section for further details). Ensemble means and spreads are calculated from these 10 member ensemble, run at a reduced resolution compared with the single high resolution (hourly output at 31 km grid spacing) 'HRES' realisation, for which these data have been produced to provide an uncertainty estimate. This dataset contains a limited selection of all available variables and have been converted to netCDF from the original GRIB files held on the ECMWF system. They have also been translated onto a regular latitude-longitude grid during the extraction process from the ECMWF holdings. For a fuller set of variables please see the linked Copernicus Data Store (CDS) data tool, linked to from this record. Note, ensemble standard deviation is often referred to as ensemble spread and is calculated as the standard deviation of the 10-members in the ensemble (i.e., including the control). It is not the sample standard deviation, and thus were calculated by dividing by 10 rather than 9 (N-1). See linked datasets for ensemble mean and ensemble spread data. The main ERA5 global atmospheric reanalysis of the covers 1979 to 2 months behind the present month. This follows on from the ERA-15, ERA-40 rand ERA-interim re-analysis projects. An initial release of ERA5 data, ERA5t, are also available upto 5 days behind the present. A limited selection of data from these runs are also available via CEDA, whilst full access is available via the Copernicus Data Store.

This dataset contains daily monthly average T159 spherical harmonics gridded, model level, analysis timestep data from the European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis (ERA) 40 program from January 1958 to December 2001. ERA-40 followed on from the ERA-15 re-analysis project. Access limited to UK based academic researchers only. These data are GRIB formatted.

Regularly gridded operational data at 1.125 degree resolution from 2000 to present containing the ongoing analyses and forecasts produced by the most recent ECMWF Integrated Forecasting System (IFS) model. The IFS is regularly updated as improvements are made to the model, computing facilities and observations used in data assimilation.

This dataset contains ERA5.1 surface level analysis parameter data ensemble means over the period 2000-2006. ERA5.1 is the European Centre for Medium-Range Weather Forecasts (ECWMF) ERA5 reanalysis project re-run for 2000-2006 to improve upon the cold bias in the lower stratosphere seen in ERA5 (see technical memorandum 859 in the linked documentation section for further details). The ensemble means are calculated from the ERA5.1 10 member ensemble, run at a reduced resolution compared with the single high resolution (hourly output at 31 km grid spacing) 'HRES' realisation, for which these data have been produced to provide an uncertainty estimate. This dataset contains a limited selection of all available variables and have been converted to netCDF from the original GRIB files held on the ECMWF system. They have also been translated onto a regular latitude-longitude grid during the extraction process from the ECMWF holdings. For a fuller set of variables please see the linked Copernicus Data Store (CDS) data tool, linked to from this record. See linked datasets for ensemble member and spread data. Note, ensemble standard deviation is often referred to as ensemble spread and is calculated as the standard deviation of the 10-members in the ensemble (i.e., including the control). It is not the sample standard deviation, and thus were calculated by dividing by 10 rather than 9 (N-1). The main ERA5 global atmospheric reanalysis of the covers 1979 to 2 months behind the present month. This follows on from the ERA-15, ERA-40 rand ERA-interim re-analysis projects. An initial release of ERA5 data, ERA5t, are also available upto 5 days behind the present. A limited selection of data from these runs are also available via CEDA, whilst full access is available via the Copernicus Data Store.

Daily and monthly regularly gridded operational data at 2.5 degree resolution from 1 March 1994 to present containing the ongoing analyses and forecasts produced by the most recent ECMWF Integrated Forecasting System (IFS) model. The IFS is regularly updated as improvements are made to the model, computing facilities and observations used in data assimilation.

This dataset contains daily monthly average T159 spherical harmonics gridded, potential temperature level, analysis timestep data from the European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis (ERA) 40 program from January 1958 to December 2001. ERA-40 followed on from the ERA-15 re-analysis project. Access limited to UK based academic researchers only. These data are GRIB formatted.

T106 Spectral data from ECMWF's operational forecasting system from 1st March 1994 to 1st November 2000 containing analyses and forecasts produced by the ECMWF Integrated Forecasting System (IFS) model on model levels. Coverage is not complete for these data. Users needing data at this resolution as opposed to the T159 data should contact user support to discuss requirements.

This dataset contains ERA5 surface level analysis parameter data. ERA5 is the 5th generation reanalysis project from the European Centre for Medium-Range Weather Forecasts (ECWMF) - see linked documentation for further details. This dataset contains a limited selection of all available variables and have been converted to netCDF from the original GRIB files held on the ECMWF system. They have also been translated onto a regular latitude-longitude grid during the extraction process from the ECMWF holdings. For a fuller set of variables please see the linked Copernicus Data Store (CDS) data tool, linked to from this record. Model level analysis and surface forecast data to complement this dataset are also available. Data from a 10 member ensemble, run at lower spatial and temporal resolution, were also produced to provide an uncertainty estimate for the output from the single high resolution (hourly output at 31 km grid spacing) 'HRES' realisation producing data in this dataset. The ERA5 global atmospheric reanalysis of the covers 1979 to 2 months behind the present month. This follows on from the ERA-15, ERA-40 rand ERA-interim re-analysis projects. An initial release of ERA5 data (ERA5t) is made roughly 5 days behind the present date. These will be subsequently reviewed ahead of being released by ECMWF as quality assured data within 3 months. CEDA holds a 6 month rolling copy of the latest ERA5t data. See related datasets linked to from this record. However, for the period 2000-2006 the initial ERA5 release was found to suffer from stratospheric temperature biases and so new runs to address this issue were performed resulting in the ERA5.1 release (see linked datasets). Note, though, that Simmons et al. 2020 (technical memo 859) report that "ERA5.1 is very close to ERA5 in the lower and middle troposphere." but users of data from this period should read the technical memo 859 for further details.