Ahead of the start of today's enforcement of Glasgow's Low Emission Zone (LEZ), questions have been raised about whether the city's public transport is fit to serve travel needs.

Over Twitter, Labour MSP Pam Duncan-Glancy, triggered a deluge of responses when she said, " The SNP Green council and government are damaging working class people with the LEZ policy. People lucky enough to have newer cars will be fine. But in the absence of a decent public transport system, how on earth are working-class people to get around?"

Among those who observed that their travel was likely to become more challenging were drivers of non-compliant cars whose homes were some distance from stations and bus routes, late-night shift workers who need to travel when services have stopped, and those living in the outskirts where service is infrequent.

One Tweeter said: "If you're a shift or late night worker, the bus is poor. Predominately low-paid workers will see the impact of not being able to access a lift and no improvement in buses. The cleaner at work calls her sons for a lift, waiting 40 mins for buses."

However, others noted that Glasgow City Centre is well served, with two stations, high and low-level services, a subway service, and multiple bus routes passing through it. It is also possible to leave a non-compliant car at a park and ride and take the subway into the centre.

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Many pointed out that half of Glasgow's households do not own a car and already use public transport for their travel needs.

But even those supporting the LEZ said that Glasgow still had some way to go in providing an adequate service - and the start of the zone has prompted calls for a more integrated system.

Public transport campaigner and chair of Get Glasgow Moving, Ellie Harrison said: "While I totally support Glasgow's LEZ and the urgent need to cut air pollution, congestion and carbon emissions, I can understand why people are angry. The sustainable alternatives to driving - i.e. comprehensive, reliable, affordable public transport - are simply not in place."

She added: "Glasgow's LEZ is all stick with no carrot. Work should have begun years ago to reform transport governance in our region, so that we have a properly-empowered and properly-funded regional transport authority (like Transport for London) that has the power to regulate buses, plan and coordinate services to integrate with the trains and Subway to meet passengers' needs."

Ms Harrison pointed out that Glasgow transport is not joined up in the way UK capital's system is. "In London," she said, "TfL controls the carrot and the stick, so you know that any money being paid by drivers towards ULEZ or congestion charge fees is ring-fenced and reinvested back into improving and expanding public transport - that's what we need here. Instead, we have Glasgow City Council doing its thing with the LEZ, we have SPT doing who knows what - meanwhile all the private bus companies remain completely unregulated and continue cutting routes and hiking up fares as they please."

"If we are serious about meeting our net zero targets, it should be our utmost priority to make the system work so we can deliver a world-class, fully-integrated, accessible, and affordable public transport network, which means everyone can get around easily without needing to own a car."

Following a fare review, First Glasgow recently announced new fares, including three-day and five-day bundles. An adult day fare in Glasgow costs £5.40, a little more than an Edinburgh day fare on Lothian buses.