We can also explore trends in extreme months.

The wettest month of the year has become 20% wetter in the period since 1836.

#RainfallRescue

Five years ago today, most historical UK monthly rainfall observations were not available to scientists.

But the 66,000 pieces of paper containing the data had been scanned.

With covid lockdown approaching we saw an opportunity to transcribe the data.

#RainfallRescue began... 🧵

We also need to thank @chrislintott.bsky.social and the @zooniverse.bsky.social team for building the Zooniverse platform that we used. It makes developing these projects possible for anyone. It's fair to say that #RainfallRescue broke records for citizen science participation in an online project.

Yes, this is the next big challenge. 350,000+ sheets now scanned (only because #RainfallRescue was such a success), containing 100+ million daily observations. Around half will be zero. But we will need AI to do the majority - this is just too big for volunteers alone.

Five years ago today I set the Rainfall Rescue citizen science project live. Would anyone actually want to help transcribe millions of hand-written rainfall records from images of 66,000 sheets of paper? #RainfallRescue

The next day was a bit surprising...
www.bbc.co.uk/news/science...

Of course, the only reason we know about Spring 1852 is the citizen science #RainfallRescue project which enabled the UK rainfall reconstructions to be extended back to 1836.

Otherwise the record would be 106mm from Summer 1995. Summer 1976 and Spring 1893 had 107mm.

www.bbc.co.uk/news/science...

The #RainfallRescue project did include recovery of the RoI monthly rainfall observations but they have yet to be integrated into the datasets by Met Éireann. Lots of potential to look at daily rainfall in both RoI & UK too, and colleagues in Maynooth are doing lots in this area.

It was the wettest July on record for the Republic of Ireland & Northern Ireland.

The difference?

For Northern Ireland, the records start in 1836. For the Republic of Ireland, they only start in 1940.

Why?

Thanks to 16,000 volunteers rescuing 5 million observations in #RainfallRescue project!

But, why are these hand-written observations important?

Before #RainfallRescue the data before 1961 was largely missing.

Now there are thousands of locations with rainfall data back to the 1870s, and hundreds back to the 1840s.

There are more observations available for the 1880s than today.