AWI-ESM and FESOM for paleoclimate studies

Recent work also illustrates the need to improve the model spatial resolution around sites where paleoclimate data have been gathered. The most efficient approach is through a multi-scale concept which has been shown to be applicable to paleoclimate modelling (Shi and Lohmann, 2016). Building upon an unstructured mesh approach (Sidorenko et al., 2015, in review) it becomes possible to zoom into regions of interest while keeping the resolution sufficiently low in other areas (e.g., Scholz et al., 2013, 2014; Ionita et al., 2016; Danek et al., 2019), see Fig. 1. The availability of efficient numerical algorithms in FESOM2 (Danilov et al., 2017) presents a unique opportunity to quantify key processes determining the fundamental relationships between climate variations and long-term climate records (instrumental and those derived from environmental archives). Building upon recent analyses shedding light on the processes that have determined the large-scale ocean circulation and climate feedbacks for the Holocene and deglacial climate (e.g., Lohmann et al., 2013; Zhang et al., 2014, 2017; Wassenburg et al., 2016; Butzin et al., 2017), we develop a unique framework with locally high-resolution (Fig. 1) aiming to analyze past, present and future climates. For paleoclimate applications there is a dedicated development of AWI-CM, the AWI-ESM.



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