Advanced Ultraviolet Radiation and Ozone Retrieval for Applications

With the launch of the Sentinel-5 Precursor (S-5P, lifted-off on 13 October 2017), Sentinel-4 (S-4) and Sentinel-5 (S-5)(from 2021 and 2023 onwards, respectively) operational missions of the ESA/EU Copernicus program, a massive amount of atmospheric composition data with unprecedented quality will become available from geostationary (GEO) and low Earth orbit (LEO) observations. Enhanced observational capabilities are expected to foster deeper insight than ever before on key issues relevant for air quality, stratospheric ozone, solar radiation, and climate. A major potential strength of the Sentinel observations lies in the exploitation of complementary information that originates from simultaneous and independent satellite measurements of the same air mass. The core purpose of the AURORA (Advanced Ultraviolet Radiation and Ozone Retrieval for Applications) project is to investigate this exploitation from a novel approach for merging data acquired in different spectral regions from on board the GEO and LEO platforms. A data processing chain is implemented and tested on synthetic observations. A new data algorithm combines the ultraviolet, visible and thermal infrared ozone products into S-4 and S-5(P) fused profiles. These fused products are then ingested into state-of-the-art data assimilation systems to obtain a unique ozone profile in analyses and forecasts mode. A comparative evaluation and validation of fused products assimilation versus the assimilation of the operational products will seek to demonstrate the improvements achieved by the proposed approach. This contribution provides a first general overview of the project, and discusses both the challenges of developing a technological infrastructure for implementing the AURORA concept, and the potential for applications of AURORA derived products, such as tropospheric ozone and UV surface radiation, in sectors such as air quality monitoring and health.


Copernicus Sentinel missions
Up to now 6 families of dedicated «Sentinel» space missions SENTINEL-1

SENTINEL-2
Multi-spectral imaging mission for land monitoring

SENTINEL-3
Multi-instrument mission for sea-surface topography, sea & land surface temperature and ocean & land color

SENTINEL-4
Geostationary mission for atmospheric monitoring

SENTINEL-5
Low Earth Orbit mission for atmospheric monitoring

Copernicus Sentinel missions
Up to now 6 families of dedicated «Sentinel» space mission SENTINEL-1

SENTINEL-2
Multi-spectral imaging mission for land monitoring

SENTINEL-3
Multi-instrument mission for sea-surface topography, sea & land surface temperature and ocean & land color

SENTINEL-4
Geostationary mission for atmospheric monitoring

SENTINEL-5
Low Earth Orbit mission for atmospheric monitoring

SENTINEL-6
Radar altimeter for global sea-surface height

S5P S5
The atmospheric Sentinel missions Sentinel-4 and Sentinel-5 address major topics related to atmospheric composition and data requirements studies were conducted per theme and per user category.

Sentinel-5
The atmospheric Sentinels aim at filling the main gaps of current/planned operational mission, such as GOME-2 and IASI (EUMETSAT MetOp) and OMPS and CRISS (US JPSS): • High temporal and spatial resolution (more cloud-free views) space-based measurements of tropospheric composition for application to AIR QUALITY • High spatial resolution and high precision monitoring of CLIMATE GASES (CO 2 , CH 4 and CO) and aerosol monitoring with sensitivity to the PBL.

• High vertical resolution measurements in the UTLS region for OZONE and CLIMATE applications
Comparison of spatial resolution of Sentinel-5 with heritage mission (image credit ESA) AURORA: Scope and objectives of the project • to investigate the potential of data fusion and data assimilation to convey complementary informatiion content of measurements acquired by the atmospheric Sentinel LEO and GEO missions into unique geophysical products.
• to focus the exploitation of the synergy between simultaneous and independent measurements of the same atmospheric traget on tropospheric ozone and UV surface radiation.

SCIENCE
• to reduce the complexity of managing the high volume of data provided by Coperncius Sentinel-4 and Sentinel-5 and increase its quality w.r.t. the operational outcome of individual instruments • to develop a prototype data processing system and demonstrate its capability to work with simulated data in conditions as close as possible to operational environment.

TECHNOLOGY
• to develop two operational downstream services (innovative mobile App for UV dosimetry and tropospheric ozone monitoring application for major cities and regional prediction of air quality) reaching a pre-market version at the end of the project.

APPLICATION Atmospheric Ozone
Instruments monitoring atmospheric ozone from space exploit a large range of observation geometries and spectral ranges.
Due to the inherent limitation of each measurement technique , none of the existing system can cover the needs for accurate observation of ozone from the surface up to the mesosphere.
By combining innovative data fusion techniques and data assimilation, the AURORA project envisages a breakthrough in atmospheric ozone sounding, in terms of improved accuracy and vertical resolution in the troposphere.

Technological objective
The technological objective is to make all the available information accessible in the most user-friendly way possible -both by project partners and by other interested scientific and commercial communities -through software interfaces deducted to each source of data, database with geographical extension (geo-database), web-services with innovative visualisation tools, automatic data access.

AURORA Technological Infrastructure
Key components of the AURORA Technological Infrastructure

GEO-DATABASE
Managing an huge amount of input data, intermediate and final results. Ready access to the pre-existing source data and the new datasets generated by the AURORA tools.

INTERFACES
Two different types of interfaces for user-friendly access to different sources of information in a harmonized and homogeneous way: • Web-service for automatic machine-to-machine data access; • Smart dashboards for users' direct data access

THE AURORA PORTAL
A web interface to access several resources and services. The GUI acts as a central point of access to all the highly accurate data elaborated throughout the project, as well as resources and services used by the end-users, including -but not limited to-scientists, academics, public authorities, environmental agencies, public etc