PTBox, a toolbox to facilitate palaeoclimate model-data analyses
Authors: Baudouin Jean-Philippe , Bothe Oliver , Chevalier Manuel , Ellerhoff Beatrice , Adam Moritz , Schoch Patrizia , Weitzel Nils , Rehfeld Kira 
Published: March 2022

&lt;p&gt;&lt;span&gt;Recent progress in modelling the Earth system has made it possible to produce transient climate simulations &lt;/span&gt;&lt;span&gt;longer than 10.000 years with comprehensive ESMs. These simulations&lt;/span&gt;&lt;span&gt; improv&lt;/span&gt;&lt;span&gt;e&lt;/span&gt;&lt;span&gt; our understanding of slow climatic feedbacks, climate state transitions, and abrupt climate changes. &lt;/span&gt;&lt;span&gt;However, a&lt;/span&gt;&lt;span&gt;ssessing the&lt;/span&gt;&lt;span&gt; quality and reliability of &lt;/span&gt;&lt;span&gt;such paleoclimate&lt;/span&gt;&lt;span&gt; simulations &lt;/span&gt;&lt;span&gt;is particularly challenging&lt;/span&gt;&lt;span&gt; due to the &lt;/span&gt;&lt;span&gt;inherent characteristic differences between model data and the climate reconstructions used to validate them.&lt;/span&gt;&lt;/p&gt;&lt;p&gt;&lt;span&gt;Here,&lt;/span&gt;&lt;span&gt; we present a&lt;/span&gt;&lt;span&gt; collection &lt;/span&gt;&lt;span&gt;of software packages&lt;/span&gt;&lt;span&gt; for &lt;/span&gt;&lt;span&gt;inter-model and model-data comparison&lt;/span&gt;&lt;span&gt;s&lt;/span&gt;&lt;span&gt; called &lt;/span&gt;&lt;span&gt;P&lt;/span&gt;&lt;span&gt;alaeo &lt;/span&gt;&lt;span&gt;ToolBox (PTBox)&lt;/span&gt;&lt;span&gt;. &lt;/span&gt;&lt;span&gt;Its first intent is to evaluate transient simulations of &lt;/span&gt;&lt;span&gt;the&lt;/span&gt;&lt;span&gt; Pal&lt;/span&gt;&lt;span&gt;M&lt;/span&gt;&lt;span&gt;od project (deglaciation, glacial inception, MIS3&lt;/span&gt;&lt;span&gt;)&lt;/span&gt; &lt;span&gt;using several proxy data syntheses. &lt;/span&gt;&lt;span&gt;V&lt;/span&gt;&lt;span&gt;arious variables are evaluated&lt;/span&gt; &lt;span&gt;(including&lt;/span&gt; &lt;span&gt;temperature, precipitation, o&lt;/span&gt;&lt;span&gt;xygen isotope&lt;/span&gt;&lt;span&gt;s&lt;/span&gt;&lt;span&gt;, &lt;/span&gt;&lt;span&gt;vegetation, &lt;/span&gt;&lt;span&gt;carbon storage&lt;/span&gt;&lt;span&gt;s&lt;/span&gt;&lt;span&gt; and fluxes&lt;/span&gt;&lt;span&gt;)&lt;/span&gt;&lt;span&gt;,&lt;/span&gt;&lt;span&gt; across a range of timescales &lt;/span&gt;&lt;span&gt;(from d&lt;/span&gt;&lt;span&gt;ecadal to multi-millenial&lt;/span&gt;&lt;span&gt;)&lt;/span&gt;&lt;span&gt;. &lt;/span&gt;&lt;span&gt;PTBox &lt;/span&gt;&lt;span&gt;provid&lt;/span&gt;&lt;span&gt;es &lt;/span&gt;&lt;span&gt;integrated model-data workflows, from data pre-processing to visualisations, &lt;/span&gt;&lt;span&gt;organised into a series of (mostly R) packages. &lt;/span&gt;&lt;span&gt;So far, PTBox&lt;/span&gt;&lt;span&gt; includes &lt;/span&gt;&lt;span&gt;1) &lt;/span&gt;&lt;span&gt;tools for pre-processing simulations and proxy data, &lt;/span&gt;&lt;span&gt;2) &lt;/span&gt;&lt;span&gt;ensemble and pseudo-proxy methods to bridge the gap between simulations and proxies and &lt;/span&gt;&lt;span&gt;to &lt;/span&gt;&lt;span&gt;quantify uncertainties, &lt;/span&gt;&lt;span&gt;3) &lt;/span&gt;&lt;span&gt;spectral methods to analyse timescale-dependent climate variability, and &lt;/span&gt;&lt;span&gt;4) &lt;/span&gt;&lt;span&gt;newly developed metrics for spatio-temporal model-data comparisons.&lt;/span&gt;&lt;/p&gt;&lt;p&gt;Finally, &lt;span&gt;PTBox is accompanied by a website (http://palmodapp.cloud.dkrz.de/) &lt;/span&gt;&lt;span&gt;with examples on how to use PTBox and interactive visualisations of&lt;/span&gt;&lt;span&gt; the datasets produced in the PalMod project.&lt;/span&gt;&lt;/p&gt;