Summers [JJA] since 1862 in the UK have become slightly drier (-0.1 mm per decade) in the linear trends of UK gridded series since 1862, but springs and autumns have got progressively wetter (1.5 & 1.7 mm per decade respectively), with winter [DJF] rainfall increasing fastest of all the seasons (3 mm per decade). As far as I see it all adds up to an annual increase in precipitation of around 6.1 mm per decade across the UK in the last 159 years. That doesnt sound a lot but when you multiply it by the almost 16 decades that have occurred since 1862 that’s at least an extra month’s rainfall. This is not as much as in the linear trend in the graph of annual precipitation for England and Wales (UKP) since 1931 which I included in my last post. That showed an annual rate of change of 9.8% in that time or around 10 mm per decade, which just goes to show how by picking the right dates and length of period you can make a linear trend just about stand on its head if you want to. All I can think is that in the UKP series the 1930’s were a rather dry decade.