100 Years of Extreme Weather

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About the map

In the UK, the top 10 hottest years in history have all been since 2002 and in the summer of 2022, July and August were the warmest months on record.

To investigate the increasingly warming climate, we have mapped the most extreme weather over the past 100 years, highlighting the areas which have experienced the greatest change.

Why it works

For each 25-year period, the maps show the number of ‘Extremely Dry’ or ‘Extremely Wet’ months for each hydrological area, when compared to the typical conditions for the locality / time of year. 

Displaying the four maps side by side clearly reveals a pattern - there has been an increase in extremely dry weather, and a decrease in extremely wet weather over the past 100 years. The use of colour really helps to visualise this change.

For the percentage change maps, proportional arrows help to show which areas have seen the greatest change in extreme dry/wet weather, and the direction of this change.

Important Steps




Tips and tricks

Phoebe Baxter, Graduate

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