There’s been a lot of talk about how climate change is resulting in wetter seasonal rainfall across the UKUK The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the continental mainland. It comprises England, Scotland, Wales and Northern Ireland.. You’ve all heard the mantra “A warmer atmosphere is capable of holding more water vapour”, almost as cliched, but not quite as elegant as the definition of a jet stream being “A fast moving ribbon of air high up in the atmosphere”. Here are a few graphs of UK and regional 30 year moving averages that I’ve drawn from the UKMOUKMO The Meteorological Office is the United Kingdom's national weather service. It is an executive agency and trading fund of the Department for Business, Energy and Industrial Strategy UKPUKP UKP is a gridded datasets of UK regional precipitation. gridded climate data to illustrate what’s been going on since 1836.
I’ve added two linear trends to the annual UK precipitation graph, one for the 1865-1993 period and the second for the last 30 years from 1994 to 2023. You’ll immediately notice a dramatic increase in UK annual precipitation since 1980. You could argue that we’ve seen upticks like this before (1860-1885 and 1915-1930), and this is one is just the result of the natural variability of the climate as they were. I don’t think so though because this increase has been going on for over 40 years and shows no sign of running out of energy and linked with increases in global temperatures during the same period can’t be coincidental. The size of the linear trend suggests that annually the UK is getting wetter at the rate of almost exactly 1″ per decade, not a lot, but it’s the change in the rate that’s more important.
Winter [DJFDJF Meteorological Winter comprising the months of December, January & February] precipitation shows a similar increase from around 1995.
Summer [JJAJJA Meteorological Summer comprising the months June, July & August] rainfall is more dramatic still, with a steady decline in rainfall suddenly being reversed in the last 20 years.
Finally here’s a grid of monthly averages and trends for the UK. As you can see not all months are getting dramatically wetter. Some regions are showing little sign of getting wetter than they have been in the years up until 1993, January, April, November and December for example, whilst March and September have become a little drier in the last 30 years. I’ll leave you to make your minds up about the underlying reason for it. 😉