The study looked at how cities like Manchester are getting hotter over time. They found that the city's heat island effect is getting stronger, making it even warmer than the surrounding areas. This is because the city is losing green spaces and becoming more urban. By the end of the century, the city could be 2.4 degrees hotter than it is now, on top of the expected climate change increase. This is due to factors like weather, clouds, wind, and the city's layout.