The two primary methods of investigating past climate are through proxy records (e.g. tree rings, ice cores, and corals) and climate models. These two methods have different strengths and weaknesses, and paleoclimate data assimilation is a method which aims to utilize the advantages of each to reconstruct past climate. Our new paper, published today in Climate of the Past (available here: https://www.clim-past.net/15/1251/2019/), explores this method and reconstructs multiple climate fields over the past 2000 years. Take a look.