The Met Office says that the world is in the middle of what’s likely to be the warmest decade in over 150 years. The data forecast that 2014-2023 will hit record temperatures not seen since 1850.
It is predicted that in the next five years the average global temperature will be above 1°C and potentially exceed 1.5°C, which is the critical threshold for climate change. A rise exceeding 2°C is regarded as the gateway to dangerous warming, and keeping temperature rise below 1.5°C is safer for the world.
A report from the Intergovernmental Panel on Climate Change (IPCC), published last year, looks at the long-term consequences of a warmer world. If the global average exceeds 1.5°C there will be more cases of extreme weather conditions, floods, droughts, and rising sea levels as the ice melts.
In response to the IPCC report Mr Khan outlined key methods to mitigate climate change. His London Environment Strategy involves retrofitting millions of homes and implementing zero-carbon standards in buildings and transport networks.
The mayor has high ambitions to make London a zero-carbon city by 2050, but he is restricted in what he can actually do.
Joseph Dutton is a policy advisor at E3G, a climate change organisation aiming to accelerate the global transition to a low-carbon future. He says that a zero-carbon transport network is the most realistic as London has devolved power over its transport system.
Implementing energy efficiency across millions of people’s homes is where things get difficult. These projects require funding and support from the current Conservative government, but they struggle to balance the short and medium-term economic interests against the long-term effect of climate change. In the past year they’ve move forward with the Heathrow expansion, fracking, and have made funding cuts to the Committee of Climate Change (CCC).
If we are to accept that a significant degree of warming will occur, then preparations are crucial.
Dutton recommends that London focuses on greening the city. Rooftop gardens and increasing the number of trees are good for air pollution as well as increasing biodiversity and the absorption of CO2.
“London is very well placed because it has the Thames barrier, which the rest of the country they don’t have equivalent. But what’s more likely with London is that rather than it being sea level flooding, it’s from rainwater,” he says.
Increasing green spaces helps with water drainage and is a more natural method of tackling urban flooding. Dutton also adds that the under-construction Thames Tideway will reroute floodwater by capturing, storing and relocating any overflow into the river.
Dr Robert Cowley specialises in sustainable cities at Kings College London. He also supports a greener city and says the biggest advantage London has is the large amount of roof space that currently isn’t used.
“Roof space could be used for solar panels but also for a lot more greenery and canopies. Reflective roofs can also lower the heat island effect. There’s a lot of stuff that we could do to alter the urban landscape of the city,” he says.