Supplemental Materials for "Variability in the oxidative capacity of the troposphere since the Last Glacial Maximum" Evaluation of present-day ICECAP simulation

The main text introduces the model framework for ICE age Chemistry And Proxies (ICECAP), a project focused on paleo-chemistry at and since the Last Glacial Maximum. The framework includes the GEOS-Chem 3-D global chemical transport model (CTM; http://www.geos-chem.org), driven by archived meteorology from the NASA Goddard Institute for Space Sciences (GISS) ModelE general circulation model (GCM). Here we evaluate the performance of the present-day ModelE-driven simulation versus a standard suite of observations used to test chemical and physical processes (e.g., transport, convection, and wet deposition). We also compare our results with state-of-the-science GEOS-Chem simulations driven by two different assimilated meteorological products from the Goddard Earth Observing System (GEOS) of the NASA Global Modeling and Assimilation Office. The GEOS4 product consists of 6 h means for most fields and 3 h means for surface fields, with a horizontal resolution of 1◦ latitude by 1.25◦ longitude and with 55 layers in the vertical. The GEOS5 product (version 5.1.0) has the same temporal resolution as GEOS4 and a horizontal resolution of 0.5◦ latitude by 0.667◦ longitude with 72 layers in the vertical. For this evaluation, the GEOS4 and GEOS5 products are upscaled to 4◦ latitude by 5◦ longitude, and to 30 and 47 vertical layers, respectively.