Non-satellite instrument techniques involved
Lidar
Gap remedies
Detailed description

Tropospheric ozone has an impact on air quality and acts as a greenhouse gas and therefore plays a role in public and environmental health, as well as climate change, linking the two subjects. In order to establish trends, more observations are needed (see G.2.10) and a rigorous error budget is needed for these observations to assure their quality. Tropospheric ozone profiles can be attained from lidar measurements (amongst others). Measurements of tropospheric ozone by means of the Differential Absorption Lidar (DIAL) technique are described in detail, metrologically characterised, and processed in a consistent comparable manner. Such data would greatly aid efforts at the characterisation of new and planned space missions which are envisaged to be capable of measuring tropospheric ozone changes and variability. Although these descriptions are now available, these should be more widely implemented across available data sources. In case of networked operation of tropospheric ozone DIAL instruments, this could be achieved by centralised data processing. However, not all available data sources are readily accessible and several rely on diverse, in-house developed processing and analysis techniques.

Operational space missions or space instruments impacted
Copernicus Sentinel 4/5
Meteosat Third Generation (MTG)
MetOp
MetOp-SG
Polar orbiters
Geostationary satellites
Passive sensors

OMPS

Validation aspects addressed
Geophysical product (Level 2 product)
Gridded product (Level 3)
Assimilated product (Level 4)
Time series and trends
Representativity (spatial, temporal)
Calibration (relative, absolute)
Gap status after GAIA-CLIM
GAIA-CLIM has partly closed this gap

GAIA-CLIM work on metrological characterisation has led to a partial resolution of this gap.

Dependencies

Gap 2.10 relates to the provision of more observations. Gap 2.11 should thus be addressed at the same time or after closing G2.10.

Tropospheric ozone has an impact on air quality and acts as a greenhouse gas and therefore plays a role in public and environmental health, as well as climate change, linking the two subjects. In order to establish tropospheric ozone trends, more high-quality and high-frequency observations are needed (see G.2.10) and a rigorous error budget is required. Measurements of tropospheric ozone by means of the Differential Absorption Lidar (DIAL) technique are close to reference quality and may meet this need if development of traceable products can be realised. The methodology of rigorous error-budget calculations is available, but needs to be implemented across available data sources.