Blue Skyfor Beijing

French Ministry of Foreign and EuropeanAffairsDélégation à l'Action extérieure des collectivitéslocales 57 Bd des Invalides75351 Paris 07 SP – FranceTel: +33 (0)1 53 69 35 36Fax: +33 (0)1 53 69 34 46

French Ministery of Economy, Finance andemploymentDirection générale du Trésor et de la Politiqueéconomique (DGTPE)139, rue de Bercy - Télédoc 23075572 Paris cedex 12 – France Tel: +33 (0)1 40 04 04 04Fax: +33 (0)1 53 18 96 04

French Economic Mission in BeijingPacific Century Place – Unit 1015, tower A2A Gong Ti Bei Lu – Chaoyang districtBeijing, 100027 – People’s Republic of ChinaTel: +86 (0) 10 6539 1300 Fax: +86 (0) 10 6539 1301

ARIA Technologies SA

Armand ALBERGEL8/10, rue de la Ferme

92100 Boulogne-BillancourtFrance

Tel: 33 (0)1 46 08 68 62Fax: 33 (0)1 41 41 93 17

E-mail: aalbergel@aria.fr Website: www.aria.fr

LEOSPHERE

Alexandre SAUVAGEBâtiment 503

Centre scientifique d’OrsayPlateau du Moulon

91400 Orsay – FranceTel: 33 (0)1 69 35 88 57 Fax: 33 (0)1 69 35 87 26

E-mail: asauvage@leosphere.frWebsite: www.leosphere.com

www.bjepb.gov.cn

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

concentrations of fine particlesand sulphur dioxide are wellabove critical thresholds. Theselast years the Beijing authoritieshave taken drastic measures toconfront this situation: theoldest iron works in thesuburban area have been movedfurther away, tens of thousandsof aging buses and taxis havebeen sent to the scrap yard andmillions of trees have beenplanted in the surrounding area.

Real-time tracing of pollutionIn order to monitor the airquality of the whole province,the Beijing EnvironmentalProtection Office has, over anumber of years, set up anetwork of 55 pollution sensors

In a joint initiative with France,the city of Beijing is nowequipped with an integratedair pollution control system,enabling local authorities tobetter understand the airquality of the city and its

surroundings, to forecast pollutionin routine modeand to makeinformed decisionsfor long-termpollutionabatement.

Several majorcities (Paris,Toulouse, Bari,Katowice, Rio deJaneiro, Doha,Kaliningrad…) arealready equippedwith the systemsoffered by AriaTechnologies.This Frenchengineering officeapplies to theatmospheric

environment a digital simulationtechnology which it has developedover the past 20 years. In the caseof Beijing however - as in manyother Asian cities – a substantiallayer of particles interferes with thesolar radiations and affects thetemperature profile, consequentlymodifying the height of theboundary layer. Understanding thedissemination of aerosolsthroughout the atmospheric columnabove Beijing is essential – probablymore than for any other location –for a precise understanding of the

way pollutants appear, transformand travel. It is precisely for thiskind of situation that Leosphere,another French companyestablished in 2004 through aFrench research laboratories spin-off, has developed the Lidar,a laser radar which detectssubmicron particles up to severalkilometers in altitude. The Lidarallows the monitoring andtracing of aerosol layers in theatmospheric column and givescritical meteorologicalinformation such as the height ofthe boundary layer where thesurface-emitted pollutantsgather. It can also be used forhorizontal mapping purposes onlarge surface emission areas witha 1.5 m resolution.The combination of these twoadvanced technologies:modelling and Lidar, offers asolution which is adapted to thecircumstances of large Chinesecities and to Beijing in particular.

Lidar and Aria Regional model

Combining two cutting edge techniques

The task of gathering the dataon pollutants emissions wasorganized along three nesteddomains: continental, regional(the provinces surroundingBeijing) and local. Two public-domain sources of informationwere used to feed the models atthe continental and regional scale:• The REAS international

inventory which accountsglobally eleven major pollutantson a 0.5 x 0.5° grid (approx.55 x 35 km at Beijing latitude)

• Satellite imaging which is usedto refine this data on somepollutants, including NO2.

At the local scale, the activecollaboration of Beijing’sEnvironmental Monitoring Centerwas essential and providedextremely precise emission data onpoint sources (industries, etc.), linesources (roads and vehicle fleet),and surface sources (human andnatural activity).

The modelling tools used in theBeijing project belong to differentcategories:• An emission model (EMMA,

TREFIC) designed to manage as awhole all the inventoried dataand to compute the trafficemissions data

• A meteorological model (MM5)which computes winds,temperatures and turbulence forseveral nested grids

• A dispersion model (CHIMERE)which forecasts theconcentrations of pollutantsover 48-hour episodes, with a specific dust module.

Real time follow-up of the aerosollayers in thetroposphere,allowing thedetection ofcomplexphenomena (suchas desert sandspassing over inaltitude) andproviding datafor the regionalair qualityvalidation –Range: 20 km.(below left)

Example of aLidar horizontalsweep fordetection ofpollution emissionsources and real-time follow-up ofpollution plumes– Range: 8 km,resolution 1.5 m(below right)

T he city of Beijing isparticularly affected by airpollution. Multiple factors

contribute to this criticalsituation: the presence of heavyindustries near the city centre,power plants running on coal,an exponential growth of roadtraffic… To make things worse,the mountains bordering Beijingto the north and west funnelthe industrial pollutants fromthe neighbouring provinces tothe city, and dust from theMongolian desert periodicallyarrives on the wind. Theconcentration of nitrogendioxide in the region hastherefore risen by 50% duringthe past ten years and, as inmany major Asian cities, the

The 2008 OlympicGames were a majorchallenge for theChinese authoritiesand the city ofBeijing

The winds coming fromMongolia blow sand over

China to such an extent thatthe phenomena appears

clearly on satellite images.17 april 2006, © ESA

providing the solid bases onwhich to build an integratedmodel, capable of tracing airpollution in Beijing and itssurroundings in real time. Takingthis cooperation into account, theFrench Ministry of Economy,Finance and Industry decided the2008 Olympic Games were anopportunity to showcase Frenchtechnology and agreed to supportthe project through the specialfund for private sector initiatives(FASEP).

An operational decision-making toolThe project, addressing a problemalready clearly identified by theBeijing authorities, was readilyagreed to and initiated at thebeginning of 2007 and the systemwas operational a few monthsbefore the Olympic Games. Withit, the Beijing authorities can nowcombine weather forecasts andpredictions of polluting emissions(traffic, energy production,industry) to simulate air quality.Measures can therefore beimplemented in full knowledge oftheir efficiency and of thebenefits they will bring tothe city.

– many having been provided byEnvironnement SA, Frenchleader in its field – whichmeasure the concentrationvalues of sulphur dioxide (SO2),nitrogen dioxide (NO2), andozone, several times per hour.This data collection has beenessential to the establishment ofscientific cooperation on particlecharacterization betweenChinese and French laboratories- including the French nationalClimate and EnvironmentalSciences Laboratory (CNRS, Gif-sur-Yvette) – with the support ofADEME and the Paris regionauthorities (Région Île-de-France). The findings have beenpublished in internationalscientific reference reviews, thus

Blue Skyfor Beijing

From emission inventory to modelling

Building up an air quality model

The continental scalecovers a large part ofChina and neighboringcountries, the regionalscale encompasses theregions which includeBeijing and the localscale is centered onBeijing and itsimmediate surroundings.

Below, from top left: 1/ Road traffic inBeijing. Colorsrepresent the intensityof the vehicles flow. 2/ A dust eventsimulated by CHIMEREwith the MB95 dustmodule MB95 (LISA). 3/ Regional forecasts ofnitrogen oxides (NOx)concentration. CHIMEREmodel, REAS data.

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