Author(s)

G Ibara-Berastegi, A Elías, I Madariaga, E Agirre & J Uria

Abstract

Bilbao is a city with a population of half a million people located in North-Central Spain. In the month of December of 1995 in Bilbao an underground railway was inaugurated, In our paper, the effects that this metro has had in the traffic and also air pollution of Bilbao City are shown. In Bilbao, as many other cities in the world, pollution due to photochenical smog and carbon monoxide are mainly due to traffic while S02 levels are not originated by traffic. In this work, traffic congestion and air pollution levels in Bilbao have been analysed jointly for the 1993-1998. For that purpose, data from the air pollution and meteorological network existing in Bilbao have been used. Also, data from the traffic network in the area. The analysed pollutants have been ozone, carbon monoxide and sulphur dioxide. In the case of ozone, meteorological effects have been removed from the original time series using the KZ filter. The results show that the new metro was at first, (year 1996) responsible for a reduction of traffic and air pollution. However, 1-2 years later traffic and air pollution recovered the increasing trend they showed since year 1993. The reason is that to obtain permanent reductions of traffic congestion and air pollution, apart from the metro, complementary measures should be adopted to discourage the use of vehicles in Bilbao.

Keywords