ClimeApp: data processing tool for monthly, global climate data from the ModE-RA palaeo-reanalysis, 1422 to 2008 CE

Abstract. ClimeApp is a newly developed web-based processing tool for the state-of-the-art ModE-RA palaeo-climate reanalysis. It presents temperature, precipitation and pressure reconstructions with global coverage and monthly resolution for the period 1422 to 2008 CE. These can be visualized as maps or time series and are compared with historical or other climate-related information through composite, correlation and regression functions. ClimeApp allows access to three data sets: (1) ModE-RA, a reanalysis that is created by assimilating early instrumental documentary and proxy data into an ensemble of climate model simulations; (2) ModE-Sim, the native version of the underlying ensemble simulations, i.e. prior to data assimilation; and (3) ModE-RAclim, an alternative version of the reanalysis product. Together, these allow researchers to separate the effects of model simulations and observations on the reanalysis. The app is designed to allow quick data processing for climatologists and easy use for non-climatologists. Specifically, it aims to help bring climate into the humanities, where climatological data still have huge potential to advance research. This paper outlines the development, processing and applications of ClimeApp and presents an updated analysis of the calamitous Tambora volcanic eruption and the 1816 “year without a summer” in Europe, using the new ModE data sets. ClimeApp is available at https://mode-ra.unibe.ch/climeapp/ (last access: 25 October 2024).