The report from Climate Ready Clyde (CRC) says the 1.8 million people who live and work in the area will face severe disruption, but around 140,000 of the area’s poorest residents will be the worst affected.
The study also estimates there is a funding shortfall of at least £184 million a year needed to begin retro-fitting homes and offices to prepare them for heatwaves, to protect roads and rail infrastructure against flooding and storms, and to plant 18 million trees which would be needed to absorb the higher temperatures and rainfall over coming decades.
CRC, a coalition of 15 councils, universities, the NHS and infrastructure bodies, says “urgent mobilisation of additional finance is crucial” to tackling the climate problems ahead and to avoid billions in lost income and emergency spending.
The report comes as the city prepares to host the UN climate summit this November, and as the impact of global warming is being felt in the US north-west and Canada where an unprecedented heatwave has killed more than 130 people.
The temperatures have also melted power cables and seen concrete roads crack.
Meanwhile land temperature in the Arctic Circle has reached peaks of 48C during a “persistent heatwave” in Siberia.
Experts say climate change is expected to increase the frequency of extreme weather events such as heatwaves.
Forecasts for Glasgow’s estimate summer temperatures could rise by at least 1.1C by 2030 and by 2.6C by 2080, with a 50 per cent chance that by 2050 Glasgow will experience summers as hot as the 32C record reached in June 2018.
Meanwhile average summer rainfall will fall, but the risk of flash floods will increase – as will winter rainfall by at least 5 per cent, as well as more intense storms.
The CRC report says the changes in temperatures and an increase in extreme weather events will put up to 100,000 homes and 18,700 businesses at risk of flooding by 2080.
As a result, it warns that work to start the adaptation of Glasgow’s existing infrastructure, with policies and regulation to require all new investment to be climate resilient, needs to begin immediately.
James Curran, the coalition’s chair and a former chief executive of the Scottish Environment Protection Agency, said a “transformational approach” was needed.
“Climate change exacerbates existing inequalities and if we don’t respond in a coherent and urgent way then the inequalities that already exist in society will be worsened,” he said.
“Some of the people who can least afford it and are least culpable in creating climate change are the ones that are going to suffer more with poor housing. They will be suffering damp in the winter; they’ll be suffering excessive heat in the summer; public transport will be disrupted.”
The report wants to see the introduction of an early warning system of public climate alerts, including surface flooding, heatwaves, droughts, wildfires and landslips.
Councils are being urged to set aside vacant land to use as flood plains, and block new developments on flood-prone areas.
A regional retro-fit framework will also be developed for building owners to assess climate resilience, and to “underpin development of a retrofit programme which ensures stock is fit for the future”, but which “should also consider wider issues such as tenure, the ability to pay, and the importance of differing lifestyles and cultures in communities”.
Further, it says there should be a framework for adapting cultural heritage assets, such as the Antonine Wall and New Lanark, in collaboration with Historic Environment Scotland, National Trust for Scotland and Heritage Trusts.
Investment in habitat restoration, tree-planting and wetlands to strengthen natural protection against flooding and heatwaves, will also be required, as well as a significant increase in spending on roads, rail lines and bridges to protect them from flooding, erosion and landslips.
Mr Curran said: “The Covid-19 pandemic took hold halfway through the production of Climate Ready Clyde’s Adaptation Strategy.
"Before that, Glasgow City Region was already under pressure, with a rising and moving population and increasing pressure on nature. We are expecting an additional 51,000 people to live here by 2043, whilst 49 per cent fewer animal and plant species live here than in 1970.
"As Glasgow City Region prepares to host world leaders for the UN Climate Change Conference (COP26) in 2021, all eyes are on the steps we take next. UN secretary general Antonio Guterres has said that the current
crisis is an unprecedented wake-up call and that we need to turn the recovery into a real opportunity to do things right for the future. We wholeheartedly agree.
"With adaptation and resilience, finance and nature based solutions all key themes of the conference, there is no better time to demonstrate their potential for transforming the world."
Chris Stark, the chief executive of the Climate Change Committee, which advises the UK’s governments on climate strategy, said the Clyde plan should be replicated by other city regions.
“You can imagine what a well-adapted city ready for climate change would look like,” he said. “And it would be a profoundly positive thing for the region and all the people living in it.”
However, there are criticisms the report avoids challenging the reliance on motorways and private car use, and does not propose far greater investment in public transport.
Dr Richard Dixon, chief executive of Friends of the Earth Scotland, said failing to tackle car use was a “missing piece” in the strategy.
But he said: “Agreeing such an ambitious plan with a wide range of bodies can have been no mean feat. It is particularly important for concentrating minds of decision-makers that there is a clear and specific price tag put on the necessary work.”