That's according to the London Climate Report...
which was commissioned after soaring temperatures, wildfires and floods in the British capital.
(Emma Howard Boyd, Chair of London Climate Report) "I think that we need a step change in the way that we are addressing all preparedness for climate shocks."
London is forecast to experience heatwaves, flooding and rising sea levels in the coming years.
The report says climate change presents a threat to life among the most vulnerable communities in London.
This includes the elderly, children, low income families, marginalized communities and vulnerable health groups.
Emma Howard Boyd is the chair of the report.
"We've had the flash flooding in the summer of 2021. We've had the heatwave the summer of 2022 when the London Fire Brigade had one of the busiest days of activity since the Second World War. And things that have appeared to be things that we need to deal with in the future have suddenly become very, very real today."
In the summer of 2022, Britain's hottest recorded day fuelled fires across Greater London, shut down key transport services, and led to the country declaring a national emergency.
Major Sadiq Khan, who commissioned the report, said he would undertake a multi-agency exercise to test the capital's preparedness for severe heat.
The report also recommends strengthening flood defences along the River Thames and improving housing standards.
"We know that this is about weaving in a, how systems function together, and a city is only as good as its weakest link."
