Digitizing observations of precipitation and temperature extremes from the meteorological reports of the Royal Meteorological Institute (1881-1900) by volunteer citizen scientists.

Data repositories and archives play a critical role as source for observational data used in the study of past weather events and climate. Therefore, data storage is the first and essential step in the process of making the data usable. The Royal Meteorological Institute (RMI) has been digitizing its archives in image scan format for several years now, thanks to BELSPO's national DIGIT programme, in order to save them. This represents a significant amount of data that can be made available as soon as it has been encoded in a way that can be easily used by everyone. In terms of human resources, it would take a lot of time and people to carry out such a task. This is why RMI is going to launch a first campaign of keying by volunteers of its archives of climate bulletins from 1881 to 1900 via the Zooniverse platform. For this campaign, volunteers will be asked to encode daily precipitation and extreme temperature data. Zooniverse provides a popular way of developing citizen science projects. Using their Project Builder interface, a custom website was created to enable volunteers to transcribe the data from the images.

This first campaign will assess the usefulness and reliability of the results collected through volunteer participation. The focus will be on the design of the encoding page, the feedback from volunteers on the tool provided, the quality of the results but also the popularity of such a process. An analysis of the results will be carried out to assess whether RMI will carry out other campaigns in the future on a wider range of climate parameters.