a b s t r a c tThis paper describes the development of a model for assessing TRAffic Noise EXposure (TRANEX) in an open-source geographic information system. Instead of using proprietary software we developed our own model for two main reasons: 1) so that the treatment of source geometry, traffic information (flows/ speeds/spatially varying diurnal traffic profiles) and receptors matched as closely as possible to that of the air pollution modelling being undertaken in the TRAFFIC project, and 2) to optimize model performance for practical reasons of needing to implement a noise model with detailed source geometry, over a large geographical area, to produce noise estimates at up to several million address locations, with limited computing resources. To evaluate TRANEX, noise estimates were compared with noise measurements made in the British cities of Leicester and Norwich. High correlation was seen between modelled and measured L Aeq,1hr (Norwich: r ¼ 0.85, p ¼ .000; Leicester: r ¼ 0.95, p ¼ .000) with average model errors of 3.1 dB. TRANEX was used to estimate noise exposures (L Aeq,1hr , L Aeq,16hr , L night ) for the resident population of London (2003e2010). Results suggest that 1.03 million (12%) people are exposed to daytime road traffic noise levels ! 65 dB(A) and 1.63 million (19%) people are exposed to night-time road traffic noise levels ! 55 dB(A). Differences in noise levels between 2010 and 2003 were on average relatively small: 0.25 dB (standard deviation: 0.89) and 0.26 dB (standard deviation: 0.87) for L Aeq,16hr and L night .

A sightings survey was carried out in the western Ligurian Sea and in the offshore waters off western Corsica during August 1992, to estimate the density and absolute abundance of cetacean species in the area. Standard line transect analysis could be applied to the two most abundant species encountered, striped dolphins (Stenella coeruleoalba) and fin whales (Balaenoptcra physains). Whale abundance was estimated as 901 individuals (coefficient of variation (CV) = 0,217 ; 95% confidence interval : 591-1,374 whales), and striped dolphin abundance was estimated as 25,614 individuals (CV = 0.253; 95% confidence interval: 15377-42658 dolphins). Densities of cetaceans presented here, compared to densities estimated in previous surveys across the entire western Mediterranean, highlight the importance of the Corso-Ligurian Basin as a main habitat for pelagic cetacean populations.Resume. -Une croisiere d'echantillonnage par observation visuelle sur transect lineaire a ete conduite dans la mer ligure occidentale et au large de l'ouest de la Corse pendant le mois d'aout 1992 pour une estimation de la densite et de la taille des populations de cetaces dans la zone. Une analyse par transect lineaire standard a pu etre appliquee aux deux especes les plus abondantes, le dauphin bleu et blanc (Stenella coeruleoalba) et le rorqual commun (Balaenoptera physalus). L'abundance du rorqual commun a ete estimee ä 901 individus (CV = 0.217 ; intervalle de confiance a 95% : 591-1 374 rorquals), et l'abondance de dauphin bleu et blanc a ete estimee a 25614 individus (CV = 0.253; Intervalle de confiance ä 95%: 15377-42658 dauphins). Les densites presentees ici, comparees aux densites estimees lors de campagnes sur 1'ensemble de la Mediterranee occidentale, mettent en relief l'importance du bassin Corso-Ligurien comme habitat preferentiel pour les populations pelagiques de cetaces.

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