EXTENSION of the Edinburgh tram network, and the proposed tram-train to Glasgow Airport (“Tram-train airport link ‘in 10 years’’’, The Herald, November 26, and Letters, November 26 & 27), have attracted the usual knee-jerk negative reaction to Scottish public transport improvements.

Extending the Edinburgh tram to Leith and Newhaven would indisputably improve the quality of transport and the environment in Edinburgh city centre. Edinburgh city streets have some of the highest levels of road traffic and atmospheric pollution in Scotland. Toxic levels of air pollution caused by diesel vehicles claim the lives of more than 200 people a year across Edinburgh.

The Scottish Government is considering a Low Emission Zone strategy. The effectiveness of this will however depend on vehicle emissions measurements which are now in some doubt.

Electric trams produce zero street emissions and are the backbone of city street transport in most advanced European cities. Businesses in Leith recognise the benefits that tram extension will bring. Given the financial problems facing the council, perhaps these businesses should consider making some contribution towards the extension.

As regards the Glasgow tram-train plan, integrating airports into the national rail network improves international accessibility to towns and cities countrywide. Most major European and English airports have rail, metro or tram links. The increasingly congested M8 gives unreliable journey times to reach Glasgow Airport at peak times, particularly from east of the city where Edinburgh Airport is likely to become easier to reach.

The question of whether the rail vehicle is "light rail" or "heavy rail" is not an issue for most travellers, as long as good interchange is available at Paisley Gilmour Street and Glasgow Central. The financing of the rail link would of course be helped if Glasgow Airport, as the main beneficiary, could contribute some capital funding to the project.

Dr John McCormick,

Chairman, Scottish Association for Public Transport, 11 Queens Crescent, Glasgow.