Beat the heat: professor’s stark warning for Glasgow projects

Professor Rohinton Emmanuel

AN expert in urban overheating has warned that plans for future construction projects in Glasgow must take into account rising temperatures.

Scotland’s largest city has been tipped to reach the same temperatures as London’s current temperature by 2050. Summer heatwaves in 2019 are thought to have killed up to 900 people in southern England – emphasising the importance of taking steps to mitigate the potential impacts.

Speaking to Project Scotland, Professor Rohinton Emmanuel said that Glasgow must begin utilising land around its waterways for future builds, increase its amount of greenspace, and improve outdoor infrastructure in preparation for the climate shift.

The academic is an expert on the topic of how climate impacts cities, having pioneered the inquiry of urban overheating in tropical cities and possessing over two decades of experience in the teaching of architecture and construction in universities across the globe.

Now director of Glasgow Caledonian University’s (GCU) BEAM Research Centre, coordinator of the Erasmus Mundus’ urban climate and sustainability joint masters degree, and lead of the Sustainable Urban Environment Research Group, Professor Emmanuel is working alongside Glasgow City Council to help it understand how the city can mitigate the impacts of climate change.

“I’ve always been intrigued by the fact that buildings are supposed to be comfortable in a tropical country – you open the window and there’s natural ventilation and so forth; it’s supposed to be good for you,” he said. “I had been hearing this throughout my studies, but it was not my experience. My experience was it is getting warmer, and it is getting difficult for buildings to be comfortable without air conditioning and the need for technology.

“That brought me to thinking of the importance of the outdoors, the climate outside the building – it seems that’s what’s driving the discomfort indoors.”

This led to the then student studying the concept of urban heat islands, which is the term given to metropolitan areas that are significantly warmer than surrounding rural areas – usually due to the modification of land surfaces and, secondly, through energy usage. Studies show that London’s urban heat bubbles can cause the city to be up to ten degrees warmer than neighbouring rural areas.

“There are a few things we can do,” Professor Emmanuel said when asked how Glasgow can prepare for similar temperatures. “The way we currently organise our buildings is to ensure each building does not cast shadow on the neighbouring building – there are regulations about not depriving our neighbour of sunlight. But I think we need to think about this going forward as more and more shading will be required as the climate continues to warm – if it goes up by another three or four degrees, it will become necessary to live in more shaded conditions.”

With 80% of the buildings that will be around in 2050 already in existence, new build is not a sole viable way of preparing Glasgow for the future. Changes to building materials, façade and amount of glass used in existing infrastructure will be needed. Professor Emmanuel explained that, when sunlight hits glass, it reflects it multiple times onto other buildings and the street. Many American cities have mitigated the problem by utilising white building materials and paint to cause the heat to reflect away from streets.

“We also need to promote green infrastructure,” Professor Emmanuel added. “Glasgow is the dear green place, or it’s supposed to be – upon coming here, I was quite surprised to learn that the amount of greenery in the city centre is less than 3%, if you exclude Glasgow Green. We have very little greenery, especially in the city centre.”

A 2014 study by Dr Kieron J. Doick on London’s Kensington Park found that the greenspace has the ability to cool the summer nighttime temperatures by an average of 1.1 degrees and a maximum of four degrees in nearby areas. As well as the obvious provision of shade, greenery consumes significant proportions of heat energy in the atmosphere to convert water in its leaves into vapour, thus cooling temperatures.

The academic explained it is not just a case of planting greenery in cities and reaping the rewards – the process is costly and difficult, often requiring gas and electricity networks to be ripped out and rearranged. Stuttgart in Germany is seen as the model city for greenspace provision, but much of this was implemented in its post-WW2 rebuild. Cities such as Tokyo and Amsterdam have requirements for greenspace provision in their planning, but again it is recognised as a long-term project rather than a quick fix.

Currently, Professor Emmanuel’s students at GCU are studying Glasgow’s avenues project – which will see a series of green infrastructure and rain gardens implemented in the city to accompany new pedestrianised areas – to note its impact on climate in order to feed back the findings to policy makers. Although there has been widespread conversation on whether cities will become predominantly residential areas post-pandemic, Professor Emmanuel is doubtful such a change will take place. And even if it did, the same rise in temperatures would be ‘probable’ due to the centres being filled with residents late at night.

“One thing I think that will improve post-pandemic, however, is how much we are able to climate-proof the outdoors,” he said. “It’s very clear from an infection control point of view that we are really unable to do much indoors – you still have to have social distancing and masks, so this is why outdoor venues are always the first to open, but in Glasgow this is not always possible. We have to improve the usability of the outdoors – more walkways, trees, parks, things that’ll allow for use in the autumn and maybe in parts of the winter – that would be good for the climate and post-Covid recovery.

“It strikes me that we don’t really use the waterfront in Glasgow. Historically, I’ve seen maps and pictures that made better use of the waterway than currently. It seems like we’re almost turning our back on the river. Facing the river would help, as water is always cooler…so opening it up, having more walkways and buildings facing it would probably help to cool the city in the years to come. That would be really beneficial if they could do it – and I know they have plans to improve the usability of the waterfront.”

Professor Emmanuel reiterated that we should all start considering the rising climate in Glasgow, but also reassure ourselves that people will adapt to the conditions, as shown in the ability for people to live in climates such as that of Dubai. He added that it is easy to see rising temperatures as a positive, but warned that many Londoners had similar responses in the 1960s to experts laying out how their city would be many decades later.