The Sentinel-5P TROPOMI Near Real Time (NRT) Tropospheric Ozone Column V2 (S5P_L2__O3_TCL_NRT) at GES DISC is the near real time version of the offline S5P_L2__O3_TCL product. These data are typically available within three hours of measurement as required by the Land Atmosphere NRT Capability Earth Observing System (LANCE). These data are intended for a rapid turnaround assessment and are only archived for up to ten days. Users who require a longer data record, or wish to conduct rigorous analysis should use the offline version of this product S5P_L2__O3_TCL.

The Copernicus Sentinel-5 Precursor (Sentinel-5P or S5P) satellite mission is one of the European Space Agency's (ESA) new mission family - Sentinels, and it is a joint initiative between the Kingdom of the Netherlands and the ESA. The sole payload on Sentinel-5P is the TROPOspheric Monitoring Instrument (TROPOMI), which is a nadir-viewing 108 degree Field-of-View push-broom grating hyperspectral spectrometer, covering the wavelength of ultraviolet-visible (UV-VIS, 270nm to 495nm), near infrared (NIR, 675nm to 775nm), and shortwave infrared (SWIR, 2305nm-2385nm). Sentinel-5P is the first of the Atmospheric Composition Sentinels and is expected to provide measurements of ozone, NO2, SO2, CH4, CO, formaldehyde, aerosols and cloud at high spatial, temporal and spectral resolutions.

Copernicus Sentinel-5P tropospheric ozone data products are retrieved by the convective-cloud-differential (CCD) algorithm to derive the tropospheric ozone columns and by the cloud slicing algorithm (CSA) to derive mean upper tropospheric ozone volume mixing ratios above the clouds. The S5P_TROPOZ_CCD algorithm uses TROPOMI Level-2 ozone column measurements and the cloud parameters provided by the S5P_CLOUD_OCRA and S5P_CLOUD_ROCINN, the average values of the tropospheric ozone columns below 270 hpa can be determined. The S5P_TROPOZ_CSA algorithm uses the correlation between could top pressure and the ozone column above the cloud. The retrieval depends on the amount of measurements with a high cloud cover. The products are restricted in the tropical region (-20 degrees to 20 degrees of latitude).

The main outputs of the Copernicus S5P/TROPOMI tropospheric ozone product include the tropospheric ozone column and corresponding errors, upper tropospheric ozone and corresponding errors, stratospheric ozone column and corresponding errors, and the retrieval quality flags. The data are stored in an enhanced netCDF-4 format. Data are stored in individual files, or granules, that contain one orbit of information. The data are stored in netCDF4 data format and files and complete files are ~20 MB.