This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 640276.
G2.11 Lack of rigorous tropospheric ozone lidar error budget availability
Submitted by Anna Mikalsen on 12 June, 2017 - 10:40
Gap abstract:
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.
Part I Gap description
Primary gap type:
- Implementation of uncertainty budget and calibration
ECVs impacted:
- Ozone
User category/Application area impacted:
- Operational services and service development (meteorological services, environmental services, Copernicus Climate Change Service (C3S) and Atmospheric Monitoring Service (CAMS), operational data assimilation development, etc.)
- Climate research (research groups working on development, validation and improvement of ECV Climate Data Records)
Non-satellite instrument techniques involved:
- Lidar
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.
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.
Part II Benefits to resolution and risks to non-resolution
| Identified benefit | User category/Application area benefitted | Probability of benefit being realised | Impacts |
|---|---|---|---|
Upcoming satellite missions will have improved capabilities for tropospheric ozone. Data available from existing tropospheric ozone DIAL instruments will be traceable. |
|
| Improved knowledge of tropospheric ozone will reduce uncertainty in radiative transfer (climate) and improve results for chemistry. |
| Identified risk | User category/Application area at risk | Probability of risk being realised | Impacts |
|---|---|---|---|
Lack of rigorous tropospheric O3 lidar error budget availability |
|
| Reduced level of traceability of tropospheric ozone lidar measurements leading to ambiguity in downstream applications such as satellite cal/val. |
Part III Gap remedies
Gap remedies:
Remedy 1: Create and disseminate a fully traceable reference quality DIAL lidar product
Primary gap remedy type:
Deployment
Secondary gap remedy type:
Technical
Deployment
Education/Training
Proposed remedy description:
Work has been undertaken to attain a fully traceable product for the DIAL lidar technique to measure tropospheric ozone profile data. A traceability chain has been fully documented. The uncertainty in each step in the processing chain has been quantified in a robust manner. Documentation as to how to undertake such traceable measurements has been published in the peer reviewed literature. Now these methods and calculations need to be implemented across potential networks and individual stations. This requires funding support to networks and individual sites to enable measurements to be undertaken in a comparable manner. It also requires support for centralised processing, archival and dissemination.
Relevance:
The issue is highly relevant for any application that uses ground based tropospheric ozone lidar data as a reference. In particular to understand the tropospheric ozone budget and the reduction of the uncertainties in estimation of the resulting radiative forcing.
Measurable outcome of success:
Established (published in peer reviewed journal) error budget calculation scheme.
Expected viability for the outcome of success:
- High
Scale of work:
- Single institution
- Consortium
Time bound to remedy:
- Less than 1 year
Indicative cost estimate (investment):
- Low cost (< 1 million)
Indicative cost estimate (exploitation):
- Yes
Ongoing annual costs to maintain (low)
Potential actors:
- EU H2020 funding
- Copernicus funding
- National funding agencies
- National Meteorological Services
- WMO
- ESA, EUMETSAT or other space agency