WP12 : Differences betweenRural and Urban Aerosols J. Pelon, L. Sauvage, Coordination Link to General Objectives : Take advantage of measurements performed in the network of advanced Lidar at selected stations to perform comparative analysis of the boundary layer height evolution Analyse evolution of aerosol properties in the PBL at the same scales in rural and Urban areas - provide data for modelling Diurnal cycle measurements on alert linked to WP6

WP12 : GENERAL Objectives : observe difference in characteristics of boundary aerosols and boundary layer height between rural and urban sites 4 groups of close-by stations involved : Athens – Oxylithos (AT) orography (sea, mountains) Napoli-Potenza (NP)  orography (sea, mountains) Hamburg-Bergerdorf (HB) Palaiseau-Paris (PP)

WP12 : Previous Analyses In Europe : measurements over Paris area Comparison of ABL characteristics in Palaiseau and Paris (Dupont et al., 1998; Menut et al., 1999)  Differences in ABL h (especially in the morning) and larger heat flux over Paris (Heat Island effect) RH effects dominant over Palaiseau (Paris warmer and dryer)

Measurements within WP 12 AT : mobile system being developed, first measurements end of 2002 HH : development of new system and implementation in Bergerdorf. Comparative measurements undertaken in several high pressure systems in HB starting in 2001 PP : Strategy was to use CIMEL micro-lidar. Operational system not available  Alternative : use of mobile Raman system developed for H20/aerosols at SA Operation started end of 2002

WP12 : Athens -Oxylithos Larger backscattering Over Athens Above the ABL Wind from Athens V Low ABLh High RH

WP12 : Lecce / Napoli / Potenza   Lecce Potenza Napoli site 18°06’E 40°20’N 15°71’E 40°06’N 14°11’E 40°50’N Distance (Km) 280 Altitude a.s.l. (m) 30 820 118 Distance from the city (Km) 3 10 Note Lidar is at the same altitude level as the city 1)    Several artificial basins have been realised in the neighbourhood 2) A high polluting industrial plant has been located very near to the lidar station 1)    Lidar station located above the ground level of the city, on its West boundary 2)    Dominant wind is from West direction 3)    On Monday and Thursday the traffic is limited by local authorities 120  

WP12 : Napoli - Potenza

WP12 : Hambourg- Bergerdorf 4 April 2002 E wind dh/dt = 100m/h

WP12 : Hambourg- Bergerdorf dh/dt = 250m/h 3 June 2002 SSE Wind

WP12 : Hambourg- Bergerdorf

WP12 : Palaiseau- Saint Mandé 19 12 02 SE wind 19/12/2002

WP12 : Palaiseau- Saint Mandé 06/01/2003 WP12 : Palaiseau- Saint Mandé NE wind

WP12 : Palaiseau- Saint Mandé 17/01/2003 WP12 : Palaiseau- Saint Mandé SE wind

WP12 : Palaiseau - Saint Mandé 24/01/2003 WP12 : Palaiseau - Saint Mandé NNE wind

WP12 : Palaiseau- Saint Mandé 27/01/2003 WP12 : Palaiseau- Saint Mandé WNW wind

WP12 : Palaiseau- Saint Mandé 30/01/2003 WP12 : Palaiseau- Saint Mandé WNW wind

WP12 : Palaiseau- Saint Mandé

WP12 : Palaiseau - Aeronet RH~cte NWW Air masses From rural Area NNE wind Air masses From Paris Area

Conclusion Difficult to set : requires two systems, two sites of Operation in nearby rural and urban conditions No significant difference in ABL h between Hamburg and Bergerdorf. ABL slightly higher in Paris. No systematic difference in RH over Paris area. Difference in backscattering have been observed but requires additional measurements