It never rains but it pours
Posted by Paul Nunn | Archive on Wednesday 28 July 2010, 9:15AM
Analysis of daily rainfall data highlights changing patterns of extreme weather events which can be missed when looking for annual or seasonal signals.
Working with CCRM, and analysing detailed daily rainfall data from the UK Met Office archives, Lloyd’s has looked at the changing patterns of extreme rainfall events in London. Comparing two 46 year periods, pre and post 1960, for one of the most complete meteorological station data set has shown a significant increase in number of extreme (>25mm in a day) rainfall events, as well as highlighting some interesting shifts on a monthly and seasonal basis.
Figure: Number of days exceeding 25mm daily rainfall threshold
Met stations going down the drain.
One worrying issue the report highlights is the closure of meteorological stations across the country will increasingly make regional analysis of weather trends harder in a future that will need big decisions and clear thinking to address climate change challenges.