Research by the Lloyd’s Emerging Risks team and the Climate Change Risk Management consultancy found rainy days of 25mm have become more frequent, increasing 33% since 1960. However, the change is most significant for days of extreme rainfall over 40mm, which recorded a 900% increase.
The study examined daily rainfall levels at Crossness Sewerage Station from 1915 to 2006 and found only one day prior to 1960 recorded rainfall exceeding 40mm, compared with ten days between 1960 and 2006. Over the entire period analysed, over half of the days with rainfall over 40mm were in September.
East London Extreme Rainfall Data
