AT2 Project Proposal

(extracted from the ACCENT proposal)


ACCENT  Atmospheric Composition Change: an European network

A shortened description of ACCENT and the integration task

"Remote sensing of atmospheric constituents from space"

1. Project Summary

2. Project objectives

2.1 Joint research programme

2.2 Tasks for integration

2.3 Outreach tasks

6.1.6 Access to remote sensing of atmospheric constituents from space

9.1.6 Remote sensing of atmospheric constituents from space (WP10)

Work Package 10


1. Project summary

Changes in atmospheric composition directly affect many aspects of life, determining climate, air quality and atmospheric inputs to ecosystems. In turn, these changes affect the fundamental necessities for human existence: human health, food production, ecosystem health and water. Atmospheric composition change research is therefore fundamental for the future orientation of Europe’s Sustainable Development strategy. The overall goals of ACCENT are to promote a common European strategy for research on atmospheric composition change, to develop and maintain durable means of communication and collaboration within the European scientific community, to facilitate this research and to optimise two-way interactions with policy-makers and the general public. ACCENT will establish Europe as an international leader in atmospheric composition change research, able to steer research agendas through its involvement in major international programmes. ACCENT furthermore aims to become the authoritative voice in Europe on issues dealing with atmospheric composition change and sustainability. The ACCENT joint research programme focuses on aerosols, biosphere-atmosphere interaction and transport and transformation of pollutants and it also looks for new partnership in economic and Earth System analysis. Integration will be achieved by creating common facilities and activities including: a dedicated interactive web portal, models, data-bases, measurement platforms, training and education opportunities, quality assurance procedures and facilities, integrated assessment and synthesis of scientific results and an interface with the general public. The excellence and the commitment of the ACCENT Partnership guarantee an effective and durable integration of the European atmospheric composition change research and that it becomes a pillar of the European Research Area.

2. Project objectives

The overall goals of ACCENT are to promote a common European strategy for research on atmospheric composition sustainability, to develop and maintain durable means of communication and collaboration within the European scientific community, to facilitate this research and to optimise the interactions with policy-makers and the general public.

In so doing, ACCENT will establish Europe as an international leader in atmospheric composition research, able to steer research agendas through its involvement in major international programmes. ACCENT will also reinforce European environmental policy-making and will support Member States and the European Union in international negotiations and agreements.

ACCENT aims to become the authoritative voice in Europe on issues dealing with atmospheric composition sustainability and its societal implications. Such authority will be based on the integration of competencies and activities of the Partners and of the wider European scientific community in the field, and on the interaction with the international scientific community.

ACCENT deals with important societal problems, and will therefore endeavour to set up a dialogue with society, involving different players such as policy-makers, non-governmental organisations and the general public as participants and contributors in its activities.

The overall goal of ACCENT will be pursued through specific objectives which can be classified as: a) a joint research programme, b) tasks for integration and c) outreach tasks.

2.1 Joint research programme

A broad common research agenda agreed by the Partners in the ACCENT Network, also in collaboration with the wider European research community, is the basis for a real integration of the European research efforts in this field, and for linking national programmes to joint European and international research projects. A biennial European Symposium would be a prime tool for defining, promoting and updating a common research agenda.

The understanding of atmospheric composition sustainability requires further advancement in a number of specific areas in atmospheric research which have been identified as currently having major gaps in knowledge or showing the need for integration with other research areas. These are:

·        the importance of aerosols for air quality and climate;

·        the biosphere-atmosphere exchange as a source and receptor of atmospheric chemical species;

·        the transport and transformation of atmospheric constituents at different spatial and temporal scales;

·        the linkages between economics, policy-making, Earth System analysis and atmospheric composition change research.

Subprojects will be set up, each with its own organisation, to focus and streamline European research within these areas. The subprojects, each led by a Co-ordinator and a Steering Committee, will organise their activities to:

·        evaluate the state of the art of research in the respective areas;

·        compile and disseminate information on national research programmes in the respective areas;

·        organise workshops on key issues;

·        propose and execute joint research activities at European and international level;

·        synthesise and integrate research results for policy-makers and the general public.

2.2 Tasks for integration

ACCENT will provide a framework for co-ordination and communication among the Partners in the Network and the wider European research community. It will thereby have the effect of restructuring European research on the sustainability of atmospheric composition, leading to a durable integration. This will be accomplished through a number of tasks organised by ACCENT.

·       Fostering interactions with the international community. European research has the potential to lead in setting the research agenda world-wide. ACCENT will promote and co-ordinate European contributions to international programmes such as the International Global Atmospheric Chemistry project (IGAC) of the International Geosphere-Biosphere Programme (IGBP), the Global Atmospheric Watch (GAW) of the World Meteorological Organisation (WMO), the European Monitoring and Evaluation Programme (EMEP) under the Convention on Long-range Transboundary Air Pollution (CLRTAP) and the Intergovernmental Panel on Climate Change (IPCC).

·       ACCENT web portal. An extensive use of Internet-based techniques will be made within ACCENT to facilitate communication within the atmospheric chemistry community, provide access to information for all and to implement a number of ACCENT activities. The web portal will also be an invaluable instrument for training activities and to reach out to policy-makers and the general public.

·       Modelling. The main goal of this task is to establish a basis for co-ordinated research activities in atmospheric modelling at different scales, from local to global, within the European research community, making the results from these activities available for the science community at large and for training purposes.

·       Access to information (organisation of databases). Emission inventories, data from monitoring networks, experimental campaigns, laboratory experiments, models and model output, and remote sensing data are essential tools for scientists, but they are presently dispersed across a multitude of institutions. ACCENT aims at rationalising the compilation and ease of access to such data, thereby increasing their usefulness for research and training.

·       Access to research infrastructures. Rectifying the lack of truly European, large-scale facilities for atmospheric research (aircraft, field stations, laboratory facilities, etc.) requires co-ordination between national facilities for joint European research. ACCENT will collect and provide information on available relevant infrastructures and will facilitate the access to them for research and training. At the same time a mechanism will be created to improve the co-ordinated activities of such infrastructures.

·       Satellite remote sensing of atmospheric constituents. The exploitation of satellite data for tropospheric research is currently poorly focused within Europe. One of the tasks of ACCENT will be to co-ordinate and promote the use of the satellite data for tropospheric research and environmental policy applications. This represents an exciting and challenging opportunity to make a significant impact on the generation, interpretation and exploitation of these novel data.

·       Data quality assurance (QA). Data of known and high quality are essential for the veracity of results on atmospheric composition change and for enhancing their impact. ACCENT will evaluate and define data quality objectives and will organise instrument comparisons in relevant areas, also in connection with other national and international programmes.

2.3 Outreach tasks

ACCENT involves European institutions and scientists at the highest level of excellence in the field of atmospheric composition research. However, in order to reach its overall objectives, ACCENT must reach out to the whole of the scientific community in Europe and raise the standards of European research. An important aspect of this is the fostering of new expertise, in particular in the area of sustainability research, and the creation of interactive links with policy and the public.

·       Providing training and education. Preparing the new generation of atmospheric scientists and increasing the expertise to a common level across Europe (including Accession Countries) is essential for the future of scientific endeavour in the field. Furthermore, the subject of atmospheric composition change has become sufficiently important to be part of the curricula of educational institutions at different levels. Outreach to the developing world is also important. An effective web-based management system will serve to administer training and education activities.

·       Synthesising research results for the policy and the public. Scientific knowledge needs to be integrated and synthesised by an authoritative body before it can be used as reference in the policy-making process and in the creation of public awareness. For this purpose, ACCENT will set up points of contact between the scientific community and policy-makers (EMEP, CAFÉ, IPCC) to facilitate a two-way communication process. ACCENT also aims at providing information on research results on atmospheric composition change and the environmental implication to the general public, directly or through the media. Internet-based information tools will again play an important role for this task.

6.1.6 Access to remote sensing of atmospheric constituents from space

In the last two decades, it has been recognised that pollution is not simply of local and regional significance but is also of global importance. The physical, chemical and biological processes, which determine the composition of the atmosphere, the conditions at the Earth’s surface and its climate, comprise a complex system having many non-linear interactions and feedback. To assess accurately our current knowledge of the Earth-atmosphere system, global information about the amounts and distributions of key atmospheric constituents and parameters is required.

In the last decade it has been demonstrated by European scientists that the inversion of measurements made by remote sensing instrumentation on board orbiting satellites yield global information about tropospheric constituents. In particular passive remote sensing in the ultraviolet, visible and infrared spectral regions has provided, for the first time, information about the tropospheric column amounts of trace gases and aerosols. The European activity in this area began with the proposals of SCIAMACHY and MERIS for ENVISAT in 1988 but were first realised with the launch of GOME, a small scale version of SCIAMACHY, on ERS-2 and POLDER-I on ADEOS-I. The principal research groups have already developed algorithms for retrieving tropospheric information from the complex spectroscopic data streams, and have produced the first global maps of the tropospheric distributions of NO2, O3, SO2, HCHO, SO2, BrO and aerosols. This activity has demonstrated how such data might be used, either alone or in combination, to study the distribution of NO2, O3 and SO2 both globally and regionally over Europe, the regional source strengths of NO2, the effects of forest fires and biomass burning, the intercontinental transport and transformation of NO2 and aerosol, the spatial distribution of PM2.5 over Europe, the presence of BrO around the Arctic and Antarctic sea ice in Spring (which corresponds with events having nearly zero surface ozone concentrations), the plumes of noxious gases resulting from volcanic eruptions, and the plumes of formaldehyde as an indicator of photochemical oxidation in areas of fossil fuel burning and biomass burning.

This task will address the need for global information about trace atmospheric constituents. It will build and improve on the efforts initiated within the EUROTRAC-2 TROPOSAT subproject to facilitate the generation of tropospheric data products, their use for research and in the medium term, and their interpretation for use in the development of environmental policy. Specifically this task deals with the growing need to co-ordinate and integrate global, regional and local data sets. It aims to ensure that the data obtainable from the new generation of satellite instruments, (e.g., ESA-ESR2/GOME, NASA-TERRA/MOPITT, ESA-ENVISAT/SCIAMACHY, MIPAS and MERIS, NASA-AURA/TES and OMI and EUMETSAT-ESA-Metop/GOME-2 and IASI) are fully used to determine two- and three- dimensional distributions and time series of trace constituents, aerosols and pollutants in the troposphere. These new tropospheric data and data products primarily result from European initiatives and have given Europe a global lead in this field. However the field is just at its beginning and there are still many scientific problems associated with the retrieval of tropospheric distributions of chemically active species, the generations of profiles of their concentrations in the atmosphere, which will be much facilitated by the use of limb sounding with SCIAMACHY, and the utilisation of the daily observations to generate a continuous picture of concentrations of trace species in space and time. A substantial effort is required in the near future to ensure that the potential of the data is fully realised.

The task will be organised into five working groups, which will be tasked to investigate and study:

·       the development and improvement of algorithms for the retrieval of profiles and concentrations of tropospheric constituents, aerosols and other parameters;

·       the development of validation strategies and the validation of  tropospheric satellite data products using existing data;

·       the use of data assimilation methods in combining observations and modelling to obtain a complete and continuous picture of the atmosphere;

·       the use of satellite data for understanding atmospheric processes;

·       the synergistic use of different instrumentation and platforms to improve our understanding of tropospheric chemistry and dynamics.

Joint working groups will be formed with other ACCENT tasks dealing with data quality assurance and the calibration, co-ordination and synthesis of models from local to global scales. This will facilitate specifically the following:

·       the development of spectroscopic data bases needed for atmospheric remote sensing

·       validation of models by comparison with observational data of a spatial density comparable to model grids;

·       strategies for the validation of the data on a continuing basis;

·       validated tropospheric data sets for use both by the group and by the tropospheric community at large;

·       quantitative determination of source strength of air pollutants;

·       capacity building for the application of satellite measurements in tropospheric research;

·       a contribution to the formation of a global chemical weather observing system as envisaged by IGOS-IGACO (International Global Observation Strategy – International Global Atmospheric Chemistry Observations); and the specifications for instrumentation for new satellite missions, in particular an instrument mounted on a geostationary satellite for making time resolved measurements of the tropospheric concentrations over Europe and Africa.

9.1.6 Remote sensing of atmospheric constituents from space (WP10)

The overarching objective of this activity is to bring together and thereby promote European competence in the use, utilisation and exploitation of remote sensing data from instrumentation on satellites for tropospheric research and as a tool to support policy. Thus both education and training and capacity building within Europe are part of this task, in connection with the ACCENT task “Training and education”. One important output is planned to be the provision of the methodology to generate the global information required to test and improve our understanding of the Earth-atmosphere system, the impact of anthropogenic activity and the accuracy of the prediction of changing atmospheric composition and its consequences. The scientific working groups within this activity have been selected to promote these objectives and are:

·       the development and improvement of algorithms for the retrieval of tropospheric data;

·       the development of validation strategies for tropospheric satellite data products using existing data:(a common activity with the ACCENT Quality assurance task);

·       the provision of tropospheric scientific data products for atmospheric research within ACCENT including the associated protocols addressing issues such as intellectual property rights;

·       the synergistic use of different instrumentation and platforms to improve our understanding of tropospheric chemistry and dynamics;

·       the use of data assimilation methods in combining observations and modelling to obtain a complete and continuous picture of the atmosphere, (a common activity with the ACCENT Modelling task).

It will be necessary, at the beginning of ACCENT, to review, in the light of the most recent research results, and thereby optimise the targets for the first 18 months with respect to the excellence and European integration. Consequently the definition of the optimal data products to be retrieved from remote sensing instrumentation aboard space-based platforms for tropospheric research, their dissemination and exploitation will be an important topic at the beginning of ACCENT. This activity needs to create a durable structure having the necessary flexibility to adapt to the changing needs of the community and availability of data.


Work Package 10

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·        The co-ordination and optimisation of the efforts of European scientists in the retrieval of the data products for tropospheric research from the measurements by instrumentation aboard orbiting satellite platform.

·        The establishment of the remote sensing scientific team and the development of a strategy to sustain this activity within ACCENT.

·        The provision of added value to the national programmes exploiting remote sensing data within the European Research Area.

·        The definition of the spectroscopic data base needs and initiation of the data base

·        The provision of global tropospheric data products of trace tropospheric constituents (gases, aerosol and clouds) using remote sensing from space.

·        The exploitation of remote sensing data from space-based instrumentation for tropospheric research within the European Research Area.

·        The provision of an interpretative interface to address the existing and developing European and international environmental policy and the role of remote sensing data from space.


Description of work

This activity addresses the needs of ACCENT for the use and application of the remote sensing of tropospheric constituents and parameters from space. At present it is envisaged that workshops will be held at a frequency of one every 6 months in addition to the ACCENT Symposium during the first 18 months. The kick off workshop of the task will address issues such as the scope of and the strategy for the activities to be implemented and the transfer of information within and external to ACCENT and the provision of information for IGACO and GMES. Two progress workshops will be take place after, the first after ~6 months and a second after ~ one year. The definition and initiation of a database of spectroscopic parameters needed for remote sensing is also planned within this activity. A book containing peer-reviewed articles, documenting the remote sensing of tropospheric constituents and parameters is proposed as an important output of the first 18 months. It is expected that this task will provide significant contribution to the ACCENT web portal, and the definition of lasting structures for information exchange between the research communities will be part of this activity.



·        ACCENT web portal contribution including the provision of data sets for research and policy support. And the Research Tools: Description of retrieval algorithms

·        Documentation: Workshop reports and Final report.

·        Scientific manuscripts

·       The preparation for meeting and related peer reviewed book to document the progress in the activities, planned for the beginning of Phase II.



Month 1: Kickoff meeting to review the status of current work, finalise priorities and strategy.

Month 3: Delivery of workshop report and the definition of the scope, priorities and strategy.

Month 6: Progress and planning meeting, describing progress on the work foci.

Month 9: Delivery of 2nd progress report.

Month 12: Progress and planning for phase II of ACCENT.

Month 15: Final task meeting within phase I of ACCENT, review of progress and the final plan of activities in Phase II ACCENT.

Month18: Phase I report including book of articles, literature, etc.


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