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PlaquettePEKINGBV2:Mise en page 1 25/05/09 14:55 Page1

www.bjepb.gov.cn

French Ministry of Foreign and European Affairs Délégation à l'Action extérieure des collectivités locales 57 Bd des Invalides 75351 Paris 07 SP – France Tel: +33 (0)1 53 69 35 36 Fax: +33 (0)1 53 69 34 46 French Ministery of Economy, Finance and employment Direction générale du Trésor et de la Politique économique (DGTPE) 139, rue de Bercy - Télédoc 230 75572 Paris cedex 12 – France Tel: +33 (0)1 40 04 04 04 Fax: +33 (0)1 53 18 96 04 French Economic Mission in Beijing Pacific Century Place – Unit 1015, tower A 2A Gong Ti Bei Lu – Chaoyang district Beijing, 100027 – People’s Republic of China Tel: +86 (0) 10 6539 1300 Fax: +86 (0) 10 6539 1301

ARIA Technologies SA Armand ALBERGEL 8/10, rue de la Ferme 92100 Boulogne-Billancourt France Tel: 33 (0)1 46 08 68 62 Fax: 33 (0)1 41 41 93 17 E-mail: aalbergel@aria.fr Website: www.aria.fr

LEOSPHERE Alexandre SAUVAGE Bâtiment 503 Centre scientifique d’Orsay Plateau du Moulon 91400 Orsay – France Tel: 33 (0)1 69 35 88 57 Fax: 33 (0)1 69 35 87 26 E-mail: asauvage@leosphere.fr Website: www.leosphere.com

Blue Sky for

Beijing


PlaquettePEKINGBV2:Mise en page 1 25/05/09 14:56 Page2

Blue Sky for

Beijing

T

he city of Beijing is particularly affected by air pollution. Multiple factors contribute to this critical situation: the presence of heavy industries near the city centre, power plants running on coal, an exponential growth of road traffic… To make things worse, the mountains bordering Beijing to the north and west funnel the industrial pollutants from the neighbouring provinces to the city, and dust from the Mongolian desert periodically arrives on the wind. The concentration of nitrogen dioxide in the region has therefore risen by 50% during the past ten years and, as in many major Asian cities, the

In a joint initiative with France, the city of Beijing is now equipped with an integrated air pollution control system, enabling local authorities to better understand the air quality of the city and its surroundings, to forecast pollution in routine mode From emission inventory to modelling and to make informed decisions Building up an for long-term air quality model pollution • A dispersion model (CHIMERE) The task of gathering the data which forecasts the on pollutants emissions was abatement.

The winds coming from Mongolia blow sand over China to such an extent that the phenomena appears clearly on satellite images. 17 april 2006, © ESA

organized along three nested domains: continental, regional (the provinces surrounding Beijing) and local. Two publicdomain sources of information were used to feed the models at the continental and regional scale: • The REAS international inventory which accounts globally eleven major pollutants on a 0.5 x 0.5° grid (approx. 55 x 35 km at Beijing latitude) • Satellite imaging which is used to refine this data on some pollutants, including NO2.

At the local scale, the active collaboration of Beijing’s Environmental Monitoring Center was essential and provided extremely precise emission data on point sources (industries, etc.), line sources (roads and vehicle fleet), and surface sources (human and natural activity). The modelling tools used in the Beijing project belong to different categories: • An emission model (EMMA, TREFIC) designed to manage as a whole all the inventoried data and to compute the traffic emissions data • A meteorological model (MM5) which computes winds, temperatures and turbulence for several nested grids

concentrations of pollutants over 48-hour episodes, with a specific dust module.

The 2008 Olympic Games were a major challenge for the Chinese authorities and the city of Beijing

concentrations of fine particles and sulphur dioxide are well above critical thresholds. These last years the Beijing authorities have taken drastic measures to confront this situation: the oldest iron works in the suburban area have been moved further away, tens of thousands of aging buses and taxis have been sent to the scrap yard and millions of trees have been planted in the surrounding area. Real-time tracing of pollution In order to monitor the air quality of the whole province, the Beijing Environmental Protection Office has, over a number of years, set up a network of 55 pollution sensors

– many having been provided by Environnement SA, French leader in its field – which measure the concentration values of sulphur dioxide (SO2), nitrogen dioxide (NO2), and ozone, several times per hour. This data collection has been essential to the establishment of scientific cooperation on particle characterization between Chinese and French laboratories - including the French national Climate and Environmental Sciences Laboratory (CNRS, Gifsur-Yvette) – with the support of ADEME and the Paris region authorities (Région Île-deFrance). The findings have been published in international scientific reference reviews, thus

Lidar and Aria Regional model

Combining two cutting edge techniques

The continental scale covers a large part of China and neighboring countries, the regional scale encompasses the regions which include Beijing and the local scale is centered on Beijing and its immediate surroundings.

Below, from top left: 1/ Road traffic in Beijing. Colors represent the intensity of the vehicles flow. 2/ A dust event simulated by CHIMERE with the MB95 dust module MB95 (LISA). 3/ Regional forecasts of nitrogen oxides (NOx) concentration. CHIMERE model, REAS data.

Real time followup of the aerosol layers in the troposphere, allowing the detection of complex phenomena (such as desert sands passing over in altitude) and providing data for the regional air quality validation – Range: 20 km. (below left) Example of a Lidar horizontal sweep for detection of pollution emission sources and realtime follow-up of pollution plumes – Range: 8 km, resolution 1.5 m (below right)

Several major cities (Paris, Toulouse, Bari, Katowice, Rio de Janeiro, Doha, Kaliningrad…) are already equipped with the systems offered by Aria Technologies. This French engineering office applies to the atmospheric environment a digital simulation technology which it has developed over the past 20 years. In the case of Beijing however - as in many other Asian cities – a substantial layer of particles interferes with the solar radiations and affects the temperature profile, consequently modifying the height of the boundary layer. Understanding the dissemination of aerosols throughout the atmospheric column above Beijing is essential – probably more than for any other location – for a precise understanding of the

way pollutants appear, transform and travel. It is precisely for this kind of situation that Leosphere, another French company established in 2004 through a French research laboratories spin-off, has developed the Lidar, a laser radar which detects submicron particles up to several kilometers in altitude. The Lidar allows the monitoring and tracing of aerosol layers in the atmospheric column and gives critical meteorological information such as the height of the boundary layer where the surface-emitted pollutants gather. It can also be used for horizontal mapping purposes on large surface emission areas with a 1.5 m resolution. The combination of these two advanced technologies: modelling and Lidar, offers a solution which is adapted to the circumstances of large Chinese cities and to Beijing in particular.

providing the solid bases on which to build an integrated model, capable of tracing air pollution in Beijing and its surroundings in real time. Taking this cooperation into account, the French Ministry of Economy, Finance and Industry decided the 2008 Olympic Games were an opportunity to showcase French technology and agreed to support the project through the special fund for private sector initiatives (FASEP). An operational decision-making tool The project, addressing a problem already clearly identified by the Beijing authorities, was readily agreed to and initiated at the beginning of 2007 and the system was operational a few months before the Olympic Games. With it, the Beijing authorities can now combine weather forecasts and predictions of polluting emissions (traffic, energy production, industry) to simulate air quality. Measures can therefore be implemented in full knowledge of their efficiency and of the benefits they will bring to the city.


Blue Sky over Beijing