(CNN)A scorching heat wave is forcing Europe to realize how dangerously unprepared its cities are for climate emergencies.
Climate change is making heat waves increasingly common and more severe, putting the lives of thousands of vulnerable people at risk.
Hot weather gets deadly in places that are not ready for it. In August 2003, during one of the most severe heat waves seen in England in recent years, mortality across the country increased 16% because of the heat. But in London, 42% more people died compared to the average of the same time periods in the previous five years.
